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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
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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)
540 GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
541 pending_timeout_tail,
543 if (pending_timeout_last == pos)
544 pending_timeout_last = NULL;
546 scheduler_driver->set_wakeup (scheduler_driver->cls,
547 pending_timeout_head->timeout);
548 queue_ready_task (pos);
554 if (GNUNET_YES == is_ready (pos, now, rs, ws))
556 GNUNET_CONTAINER_DLL_remove (pending_head,
559 queue_ready_task (pos);
567 * Request the shutdown of a scheduler. Marks all tasks
568 * awaiting shutdown as ready. Note that tasks
569 * scheduled with #GNUNET_SCHEDULER_add_shutdown() AFTER this call
570 * will be delayed until the next shutdown signal.
573 GNUNET_SCHEDULER_shutdown ()
575 struct GNUNET_SCHEDULER_Task *pos;
577 while (NULL != (pos = shutdown_head))
579 GNUNET_CONTAINER_DLL_remove (shutdown_head,
582 pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
583 queue_ready_task (pos);
589 * Destroy a task (release associated resources)
591 * @param t task to destroy
594 destroy_task (struct GNUNET_SCHEDULER_Task *t)
596 if (NULL != t->read_set)
597 GNUNET_NETWORK_fdset_destroy (t->read_set);
598 if (NULL != t->write_set)
599 GNUNET_NETWORK_fdset_destroy (t->write_set);
601 GNUNET_free (t->backtrace_strings);
608 * Output stack trace of task @a t.
610 * @param t task to dump stack trace of
613 dump_backtrace (struct GNUNET_SCHEDULER_Task *t)
618 for (i = 0; i < t->num_backtrace_strings; i++)
619 LOG (GNUNET_ERROR_TYPE_DEBUG,
620 "Task %p trace %u: %s\n",
623 t->backtrace_strings[i]);
629 * Run at least one task in the highest-priority queue that is not
630 * empty. Keep running tasks until we are either no longer running
631 * "URGENT" tasks or until we have at least one "pending" task (which
632 * may become ready, hence we should select on it). Naturally, if
633 * there are no more ready tasks, we also return.
635 * @param rs FDs ready for reading
636 * @param ws FDs ready for writing
639 run_ready (struct GNUNET_NETWORK_FDSet *rs,
640 struct GNUNET_NETWORK_FDSet *ws)
642 enum GNUNET_SCHEDULER_Priority p;
643 struct GNUNET_SCHEDULER_Task *pos;
645 max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
648 if (0 == ready_count)
650 GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
651 /* yes, p>0 is correct, 0 is "KEEP" which should
652 * always be an empty queue (see assertion)! */
653 for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
659 GNUNET_assert (NULL != pos); /* ready_count wrong? */
660 GNUNET_CONTAINER_DLL_remove (ready_head[p],
664 current_priority = pos->priority;
665 current_lifeness = pos->lifeness;
668 if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us >
669 DELAY_THRESHOLD.rel_value_us)
671 LOG (GNUNET_ERROR_TYPE_DEBUG,
672 "Task %p took %s to be scheduled\n",
674 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time),
678 tc.reason = pos->reason;
679 tc.read_ready = (NULL == pos->read_set) ? rs : pos->read_set;
680 if ((-1 != pos->read_fd) &&
681 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)))
682 GNUNET_NETWORK_fdset_set_native (rs, pos->read_fd);
683 tc.write_ready = (NULL == pos->write_set) ? ws : pos->write_set;
684 if ((-1 != pos->write_fd) &&
685 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
686 GNUNET_NETWORK_fdset_set_native (ws, pos->write_fd);
687 if ((0 != (tc.reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
688 (-1 != pos->write_fd) &&
689 (!GNUNET_NETWORK_fdset_test_native (ws, pos->write_fd)))
690 GNUNET_assert (0); // added to ready in previous select loop!
691 LOG (GNUNET_ERROR_TYPE_DEBUG,
692 "Running task: %p\n",
694 pos->callback (pos->callback_cls);
695 dump_backtrace (pos);
700 while ((NULL == pending_head) || (p >= max_priority_added));
705 * Pipe used to communicate shutdown via signal.
707 static struct GNUNET_DISK_PipeHandle *shutdown_pipe_handle;
710 * Process ID of this process at the time we installed the various
716 * Signal handler called for SIGPIPE.
728 * Wait for a short time.
729 * Sleeps for @a ms ms (as that should be long enough for virtually all
730 * modern systems to context switch and allow another process to do
733 * @param ms how many ms to wait
736 short_wait (unsigned int ms)
738 struct GNUNET_TIME_Relative timeout;
740 timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, ms);
741 (void) GNUNET_NETWORK_socket_select (NULL, NULL, NULL, timeout);
746 * Signal handler called for signals that should cause us to shutdown.
749 sighandler_shutdown ()
752 int old_errno = errno; /* backup errno */
754 if (getpid () != my_pid)
755 exit (1); /* we have fork'ed since the signal handler was created,
756 * ignore the signal, see https://gnunet.org/vfork discussion */
757 GNUNET_DISK_file_write (GNUNET_DISK_pipe_handle
758 (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE),
765 * Check if the system is still alive. Trigger shutdown if we
766 * have tasks, but none of them give us lifeness.
768 * @return #GNUNET_OK to continue the main loop,
774 struct GNUNET_SCHEDULER_Task *t;
778 for (t = pending_head; NULL != t; t = t->next)
779 if (t->lifeness == GNUNET_YES)
781 for (t = shutdown_head; NULL != t; t = t->next)
782 if (t->lifeness == GNUNET_YES)
784 for (t = pending_timeout_head; NULL != t; t = t->next)
785 if (t->lifeness == GNUNET_YES)
787 if (NULL != shutdown_head)
789 GNUNET_SCHEDULER_shutdown ();
797 int while_live(struct GNUNET_NETWORK_FDSet *rs, struct GNUNET_NETWORK_FDSet *ws)
800 unsigned int busy_wait_warning;
801 unsigned long long last_tr;
802 const struct GNUNET_DISK_FileHandle *pr;
804 struct GNUNET_TIME_Relative timeout;
806 busy_wait_warning = 0;
807 pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
808 GNUNET_DISK_PIPE_END_READ);
809 GNUNET_assert (NULL != pr);
812 while (GNUNET_OK == check_lifeness ())
814 GNUNET_NETWORK_fdset_zero (rs);
815 GNUNET_NETWORK_fdset_zero (ws);
816 timeout = GNUNET_TIME_UNIT_FOREVER_REL;
817 update_sets (rs, ws, &timeout);
818 GNUNET_NETWORK_fdset_handle_set (rs, pr);
821 /* no blocking, more work already ready! */
822 timeout = GNUNET_TIME_UNIT_ZERO;
824 if (NULL == scheduler_select)
825 ret = GNUNET_NETWORK_socket_select (rs,
830 ret = scheduler_select (scheduler_select_cls,
835 if (ret == GNUNET_SYSERR)
840 LOG_STRERROR (GNUNET_ERROR_TYPE_ERROR, "select");
845 snprintf (lsof, sizeof (lsof), "lsof -p %d", getpid ());
848 if (0 != system (lsof))
849 LOG_STRERROR (GNUNET_ERROR_TYPE_WARNING,
854 struct GNUNET_SCHEDULER_Task *t;
856 for (t = pending_head; NULL != t; t = t->next)
858 if (-1 != t->read_fd)
860 int flags = fcntl (t->read_fd, F_GETFD);
861 if ((flags == -1) && (errno == EBADF))
863 LOG (GNUNET_ERROR_TYPE_ERROR,
864 "Got invalid file descriptor %d!\n",
869 if (-1 != t->write_fd)
871 int flags = fcntl (t->write_fd, F_GETFD);
872 if ((flags == -1) && (errno == EBADF))
874 LOG (GNUNET_ERROR_TYPE_ERROR,
875 "Got invalid file descriptor %d!\n",
887 (0 == timeout.rel_value_us) &&
888 (busy_wait_warning > 16) )
890 LOG (GNUNET_ERROR_TYPE_WARNING,
891 "Looks like we're busy waiting...\n");
892 short_wait (100); /* mitigate */
894 check_ready (rs, ws);
896 if (GNUNET_NETWORK_fdset_handle_isset (rs, pr))
898 /* consume the signal */
899 GNUNET_DISK_file_read (pr, &c, sizeof (c));
900 /* mark all active tasks as ready due to shutdown */
901 GNUNET_SCHEDULER_shutdown ();
903 if (last_tr == tasks_run)
911 busy_wait_warning = 0;
918 * Initialize and run scheduler. This function will return when all
919 * tasks have completed. On systems with signals, receiving a SIGTERM
920 * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown()
921 * to be run after the active task is complete. As a result, SIGTERM
922 * causes all active tasks to be scheduled with reason
923 * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
924 * afterwards will execute normally!). Note that any particular signal
925 * will only shut down one scheduler; applications should always only
926 * create a single scheduler.
928 * @param task task to run immediately
929 * @param task_cls closure of @a task
932 GNUNET_SCHEDULER_run (GNUNET_SCHEDULER_TaskCallback task,
936 GNUNET_SCHEDULER_run_with_driver(GNUNET_SCHEDULER_driver_select (), task, task_cls);
942 * Obtain the task context, giving the reason why the current task was
945 * @return current tasks' scheduler context
947 const struct GNUNET_SCHEDULER_TaskContext *
948 GNUNET_SCHEDULER_get_task_context ()
950 GNUNET_assert (NULL != active_task);
956 * Get information about the current load of this scheduler. Use this
957 * function to determine if an elective task should be added or simply
958 * dropped (if the decision should be made based on the number of
959 * tasks ready to run).
961 * @param p priority level to look at
962 * @return number of tasks pending right now
965 GNUNET_SCHEDULER_get_load (enum GNUNET_SCHEDULER_Priority p)
967 struct GNUNET_SCHEDULER_Task *pos;
970 GNUNET_assert (NULL != active_task);
971 if (p == GNUNET_SCHEDULER_PRIORITY_COUNT)
973 if (p == GNUNET_SCHEDULER_PRIORITY_KEEP)
974 p = current_priority;
976 for (pos = ready_head[check_priority (p)]; NULL != pos; pos = pos->next)
983 initFdInfo(struct GNUNET_SCHEDULER_Task *t,
984 const struct GNUNET_NETWORK_Handle *read_nh,
985 const struct GNUNET_NETWORK_Handle *write_nh,
986 const struct GNUNET_DISK_FileHandle *read_fh,
987 const struct GNUNET_DISK_FileHandle *write_fh)
989 // either only network handles or only file handles are allowed
990 GNUNET_assert (!((NULL != read_nh || NULL != write_nh) && (NULL != read_fh || NULL != write_fh)));
992 if (NULL != read_nh && NULL != write_nh)
995 t->fds = GNUNET_new_array (2, struct GNUNET_SCHEDULER_FdInfo);
996 const struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fd = read_nh, .et = GNUNET_SCHEDULER_ET_IN, .sock = GNUNET_NETWORK_get_fd (read_nh)};
997 const struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fd = write_nh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = GNUNET_NETWORK_get_fd (write_nh)};
999 const struct GNUNET_SCHEDULER_FdInfo array[2] = {read_fdi, write_fdi};
1002 else if (NULL != read_fh && NULL != write_fh)
1005 t->fds = GNUNET_new_array (2, struct GNUNET_SCHEDULER_FdInfo);
1006 const struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fh = read_fh, .et = GNUNET_SCHEDULER_ET_IN};
1007 const struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fh = write_fh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = GNUNET_NETWORK_get_fd (write_nh)};
1008 const struct GNUNET_SCHEDULER_FdInfo array[2] = {read_fdi, write_fdi};
1011 else if (NULL != read_nh)
1013 struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fd = read_nh, .et = GNUNET_SCHEDULER_ET_IN, .sock = GNUNET_NETWORK_get_fd (read_nh)};
1016 else if (NULL != write_nh)
1018 struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fd = write_nh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = GNUNET_NETWORK_get_fd (write_nh)};
1021 else if (NULL != read_fh)
1023 struct GNUNET_SCHEDULER_FdInfo read_fdi = { .fh = read_fh, .et = GNUNET_SCHEDULER_ET_IN, .sock = read_fh->fd};
1026 else if (NULL != write_fh)
1028 struct GNUNET_SCHEDULER_FdInfo write_fdi = { .fh = write_fh, .et = GNUNET_SCHEDULER_ET_OUT, .sock = write_fh->fd};
1034 int scheduler_multi_function_call(struct GNUNET_SCHEDULER_Task *t, int (*driver_func)())
1036 if (t->fds_len > 1){
1037 int success = GNUNET_YES;
1038 for (int i = 0; i < t->fds_len;i++){
1039 success = driver_func(scheduler_driver->cls, t , t->fds+i) && success;
1043 return driver_func(scheduler_driver->cls, t , t->fds);
1049 * Cancel the task with the specified identifier.
1050 * The task must not yet have run.
1052 * @param task id of the task to cancel
1053 * @return original closure of the task
1056 GNUNET_SCHEDULER_cancel (struct GNUNET_SCHEDULER_Task *task)
1058 enum GNUNET_SCHEDULER_Priority p;
1061 GNUNET_assert ( (NULL != active_task) ||
1062 (GNUNET_NO == task->lifeness) );
1063 if (! task->in_ready_list)
1065 if ( (-1 == task->read_fd) &&
1066 (-1 == task->write_fd) &&
1067 (NULL == task->read_set) &&
1068 (NULL == task->write_set) )
1070 if (GNUNET_YES == task->on_shutdown)
1071 GNUNET_CONTAINER_DLL_remove (shutdown_head,
1076 GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
1077 pending_timeout_tail,
1079 if (pending_timeout_last == task)
1080 pending_timeout_last = NULL;
1082 scheduler_driver->set_wakeup (scheduler_driver->cls,
1083 pending_timeout_head->timeout);
1085 //TODO check if this is redundant
1086 if (task == pending_timeout_last)
1087 pending_timeout_last = NULL;
1091 GNUNET_CONTAINER_DLL_remove (pending_head,
1094 scheduler_multi_function_call(task, scheduler_driver->del);
1099 p = check_priority (task->priority);
1100 GNUNET_CONTAINER_DLL_remove (ready_head[p],
1105 ret = task->callback_cls;
1106 LOG (GNUNET_ERROR_TYPE_DEBUG,
1107 "Canceling task %p\n",
1109 destroy_task (task);
1115 * Initialize backtrace data for task @a t
1117 * @param t task to initialize
1120 init_backtrace (struct GNUNET_SCHEDULER_Task *t)
1123 void *backtrace_array[MAX_TRACE_DEPTH];
1125 t->num_backtrace_strings
1126 = backtrace (backtrace_array, MAX_TRACE_DEPTH);
1127 t->backtrace_strings =
1128 backtrace_symbols (backtrace_array,
1129 t->num_backtrace_strings);
1136 * Continue the current execution with the given function. This is
1137 * similar to the other "add" functions except that there is no delay
1138 * and the reason code can be specified.
1140 * @param task main function of the task
1141 * @param task_cls closure for @a task
1142 * @param reason reason for task invocation
1143 * @param priority priority to use for the task
1146 GNUNET_SCHEDULER_add_with_reason_and_priority (GNUNET_SCHEDULER_TaskCallback task,
1148 enum GNUNET_SCHEDULER_Reason reason,
1149 enum GNUNET_SCHEDULER_Priority priority)
1151 struct GNUNET_SCHEDULER_Task *t;
1153 GNUNET_assert (NULL != task);
1154 GNUNET_assert ((NULL != active_task) ||
1155 (GNUNET_SCHEDULER_REASON_STARTUP == reason));
1156 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1160 t->callback_cls = task_cls;
1162 t->start_time = GNUNET_TIME_absolute_get ();
1165 t->priority = priority;
1166 t->lifeness = current_lifeness;
1167 LOG (GNUNET_ERROR_TYPE_DEBUG,
1168 "Adding continuation task %p\n",
1171 queue_ready_task (t);
1176 * Schedule a new task to be run at the specified time. The task
1177 * will be scheduled for execution at time @a at.
1179 * @param at time when the operation should run
1180 * @param priority priority to use for the task
1181 * @param task main function of the task
1182 * @param task_cls closure of @a task
1183 * @return unique task identifier for the job
1184 * only valid until @a task is started!
1186 struct GNUNET_SCHEDULER_Task *
1187 GNUNET_SCHEDULER_add_at_with_priority (struct GNUNET_TIME_Absolute at,
1188 enum GNUNET_SCHEDULER_Priority priority,
1189 GNUNET_SCHEDULER_TaskCallback task,
1192 struct GNUNET_SCHEDULER_Task *t;
1193 struct GNUNET_SCHEDULER_Task *pos;
1194 struct GNUNET_SCHEDULER_Task *prev;
1196 GNUNET_assert (NULL != active_task);
1197 GNUNET_assert (NULL != task);
1198 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1200 t->callback_cls = task_cls;
1204 t->start_time = GNUNET_TIME_absolute_get ();
1207 t->priority = priority;
1208 t->lifeness = current_lifeness;
1209 /* try tail first (optimization in case we are
1210 * appending to a long list of tasks with timeouts) */
1211 if ( (NULL == pending_timeout_head) ||
1212 (at.abs_value_us < pending_timeout_head->timeout.abs_value_us) )
1214 GNUNET_CONTAINER_DLL_insert (pending_timeout_head,
1215 pending_timeout_tail,
1217 scheduler_driver->set_wakeup(scheduler_driver->cls,pending_timeout_head->timeout);
1221 /* first move from heuristic start backwards to before start time */
1222 prev = pending_timeout_last;
1223 while ( (NULL != prev) &&
1224 (prev->timeout.abs_value_us > t->timeout.abs_value_us) )
1226 /* now, move from heuristic start (or head of list) forward to insertion point */
1228 pos = pending_timeout_head;
1231 while ( (NULL != pos) &&
1232 ( (pos->timeout.abs_value_us <= t->timeout.abs_value_us) ||
1233 (0 != pos->reason) ) )
1238 GNUNET_CONTAINER_DLL_insert_after (pending_timeout_head,
1239 pending_timeout_tail,
1243 /* finally, update heuristic insertion point to last insertion... */
1244 pending_timeout_last = t;
1246 LOG (GNUNET_ERROR_TYPE_DEBUG,
1247 "Adding task: %p\n",
1255 * Schedule a new task to be run with a specified delay. The task
1256 * will be scheduled for execution once the delay has expired.
1258 * @param delay when should this operation time out?
1259 * @param priority priority to use for the task
1260 * @param task main function of the task
1261 * @param task_cls closure of @a task
1262 * @return unique task identifier for the job
1263 * only valid until @a task is started!
1265 struct GNUNET_SCHEDULER_Task *
1266 GNUNET_SCHEDULER_add_delayed_with_priority (struct GNUNET_TIME_Relative delay,
1267 enum GNUNET_SCHEDULER_Priority priority,
1268 GNUNET_SCHEDULER_TaskCallback task,
1271 return GNUNET_SCHEDULER_add_at_with_priority (GNUNET_TIME_relative_to_absolute (delay),
1279 * Schedule a new task to be run with a specified priority.
1281 * @param prio how important is the new task?
1282 * @param task main function of the task
1283 * @param task_cls closure of @a task
1284 * @return unique task identifier for the job
1285 * only valid until @a task is started!
1287 struct GNUNET_SCHEDULER_Task *
1288 GNUNET_SCHEDULER_add_with_priority (enum GNUNET_SCHEDULER_Priority prio,
1289 GNUNET_SCHEDULER_TaskCallback task,
1292 return GNUNET_SCHEDULER_add_delayed_with_priority (GNUNET_TIME_UNIT_ZERO,
1300 * Schedule a new task to be run at the specified time. The task
1301 * will be scheduled for execution once specified time has been
1302 * reached. It will be run with the DEFAULT priority.
1304 * @param at time at which this operation should run
1305 * @param task main function of the task
1306 * @param task_cls closure of @a task
1307 * @return unique task identifier for the job
1308 * only valid until @a task is started!
1310 struct GNUNET_SCHEDULER_Task *
1311 GNUNET_SCHEDULER_add_at (struct GNUNET_TIME_Absolute at,
1312 GNUNET_SCHEDULER_TaskCallback task,
1315 return GNUNET_SCHEDULER_add_at_with_priority (at,
1316 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1323 * Schedule a new task to be run with a specified delay. The task
1324 * will be scheduled for execution once the delay has expired. It
1325 * will be run with the DEFAULT priority.
1327 * @param delay when should this operation time out?
1328 * @param task main function of the task
1329 * @param task_cls closure of @a task
1330 * @return unique task identifier for the job
1331 * only valid until @a task is started!
1333 struct GNUNET_SCHEDULER_Task *
1334 GNUNET_SCHEDULER_add_delayed (struct GNUNET_TIME_Relative delay,
1335 GNUNET_SCHEDULER_TaskCallback task,
1338 return GNUNET_SCHEDULER_add_delayed_with_priority (delay,
1339 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1346 * Schedule a new task to be run as soon as possible. Note that this
1347 * does not guarantee that this will be the next task that is being
1348 * run, as other tasks with higher priority (or that are already ready
1349 * to run) might get to run first. Just as with delays, clients must
1350 * not rely on any particular order of execution between tasks
1351 * scheduled concurrently.
1353 * The task will be run with the DEFAULT priority.
1355 * @param task main function of the task
1356 * @param task_cls closure of @a task
1357 * @return unique task identifier for the job
1358 * only valid until @a task is started!
1360 struct GNUNET_SCHEDULER_Task *
1361 GNUNET_SCHEDULER_add_now (GNUNET_SCHEDULER_TaskCallback task,
1364 return GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_ZERO,
1371 * Schedule a new task to be run on shutdown, that is when a CTRL-C
1372 * signal is received, or when #GNUNET_SCHEDULER_shutdown() is being
1375 * @param task main function of the task
1376 * @param task_cls closure of @a task
1377 * @return unique task identifier for the job
1378 * only valid until @a task is started!
1380 struct GNUNET_SCHEDULER_Task *
1381 GNUNET_SCHEDULER_add_shutdown (GNUNET_SCHEDULER_TaskCallback task,
1384 struct GNUNET_SCHEDULER_Task *t;
1386 GNUNET_assert (NULL != active_task);
1387 GNUNET_assert (NULL != task);
1388 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1390 t->callback_cls = task_cls;
1394 t->start_time = GNUNET_TIME_absolute_get ();
1396 t->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
1397 t->priority = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN;
1398 t->on_shutdown = GNUNET_YES;
1399 t->lifeness = GNUNET_YES;
1400 GNUNET_CONTAINER_DLL_insert (shutdown_head,
1403 LOG (GNUNET_ERROR_TYPE_DEBUG,
1404 "Adding task: %p\n",
1412 * Schedule a new task to be run as soon as possible with the
1413 * (transitive) ignore-shutdown flag either explicitly set or
1414 * explicitly enabled. This task (and all tasks created from it,
1415 * other than by another call to this function) will either count or
1416 * not count for the "lifeness" of the process. This API is only
1417 * useful in a few special cases.
1419 * @param lifeness #GNUNET_YES if the task counts for lifeness, #GNUNET_NO if not.
1420 * @param task main function of the task
1421 * @param task_cls closure of @a task
1422 * @return unique task identifier for the job
1423 * only valid until @a task is started!
1425 struct GNUNET_SCHEDULER_Task *
1426 GNUNET_SCHEDULER_add_now_with_lifeness (int lifeness,
1427 GNUNET_SCHEDULER_TaskCallback task,
1430 struct GNUNET_SCHEDULER_Task *ret;
1432 ret = GNUNET_SCHEDULER_add_now (task, task_cls);
1433 ret->lifeness = lifeness;
1439 * Schedule a new task to be run with a specified delay or when any of
1440 * the specified file descriptor sets is ready. The delay can be used
1441 * as a timeout on the socket(s) being ready. The task will be
1442 * scheduled for execution once either the delay has expired or any of
1443 * the socket operations is ready. This is the most general
1444 * function of the "add" family. Note that the "prerequisite_task"
1445 * must be satisfied in addition to any of the other conditions. In
1446 * other words, the task will be started when
1448 * (prerequisite-run)
1454 * @param delay how long should we wait?
1455 * @param priority priority to use
1456 * @param rfd file descriptor we want to read (can be -1)
1457 * @param wfd file descriptors we want to write (can be -1)
1458 * @param task main function of the task
1459 * @param task_cls closure of @a task
1460 * @return unique task identifier for the job
1461 * only valid until @a task is started!
1464 static struct GNUNET_SCHEDULER_Task *
1465 add_without_sets (struct GNUNET_TIME_Relative delay,
1466 enum GNUNET_SCHEDULER_Priority priority,
1467 const struct GNUNET_NETWORK_Handle *read_nh,
1468 const struct GNUNET_NETWORK_Handle *write_nh,
1469 const struct GNUNET_DISK_FileHandle *read_fh,
1470 const struct GNUNET_DISK_FileHandle *write_fh,
1473 GNUNET_SCHEDULER_TaskCallback task,
1476 struct GNUNET_SCHEDULER_Task *t;
1478 GNUNET_assert (NULL != active_task);
1479 GNUNET_assert (NULL != task);
1480 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1481 initFdInfo (t, read_nh, write_nh, read_fh, write_fh);
1483 t->callback_cls = task_cls;
1487 int flags = fcntl (rfd, F_GETFD);
1489 if ((flags == -1) && (errno == EBADF))
1491 LOG (GNUNET_ERROR_TYPE_ERROR,
1492 "Got invalid file descriptor %d!\n",
1500 int flags = fcntl (wfd, F_GETFD);
1502 if (flags == -1 && errno == EBADF)
1504 LOG (GNUNET_ERROR_TYPE_ERROR,
1505 "Got invalid file descriptor %d!\n",
1514 t->start_time = GNUNET_TIME_absolute_get ();
1516 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1517 t->priority = check_priority ((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : priority);
1518 t->lifeness = current_lifeness;
1519 GNUNET_CONTAINER_DLL_insert (pending_head,
1522 scheduler_multi_function_call(t, scheduler_driver->add);
1523 max_priority_added = GNUNET_MAX (max_priority_added,
1525 LOG (GNUNET_ERROR_TYPE_DEBUG,
1535 * Schedule a new task to be run with a specified delay or when the
1536 * specified file descriptor is ready for reading. The delay can be
1537 * used as a timeout on the socket being ready. The task will be
1538 * scheduled for execution once either the delay has expired or the
1539 * socket operation is ready. It will be run with the DEFAULT priority.
1541 * @param delay when should this operation time out?
1542 * @param rfd read file-descriptor
1543 * @param task main function of the task
1544 * @param task_cls closure of @a task
1545 * @return unique task identifier for the job
1546 * only valid until @a task is started!
1548 struct GNUNET_SCHEDULER_Task *
1549 GNUNET_SCHEDULER_add_read_net (struct GNUNET_TIME_Relative delay,
1550 struct GNUNET_NETWORK_Handle *rfd,
1551 GNUNET_SCHEDULER_TaskCallback task,
1554 return GNUNET_SCHEDULER_add_read_net_with_priority (delay,
1555 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1556 rfd, task, task_cls);
1561 * Schedule a new task to be run with a specified priority and to be
1562 * run after the specified delay or when the specified file descriptor
1563 * is ready for reading. The delay can be used as a timeout on the
1564 * socket being ready. The task will be scheduled for execution once
1565 * either the delay has expired or the socket operation is ready. It
1566 * will be run with the DEFAULT priority.
1568 * @param delay when should this operation time out?
1569 * @param priority priority to use for the task
1570 * @param rfd read file-descriptor
1571 * @param task main function of the task
1572 * @param task_cls closure of @a task
1573 * @return unique task identifier for the job
1574 * only valid until @a task is started!
1576 struct GNUNET_SCHEDULER_Task *
1577 GNUNET_SCHEDULER_add_read_net_with_priority (struct GNUNET_TIME_Relative delay,
1578 enum GNUNET_SCHEDULER_Priority priority,
1579 struct GNUNET_NETWORK_Handle *rfd,
1580 GNUNET_SCHEDULER_TaskCallback task,
1583 return GNUNET_SCHEDULER_add_net_with_priority (delay, priority,
1592 * Schedule a new task to be run with a specified delay or when the
1593 * specified file descriptor is ready for writing. The delay can be
1594 * used as a timeout on the socket being ready. The task will be
1595 * scheduled for execution once either the delay has expired or the
1596 * socket operation is ready. It will be run with the priority of
1599 * @param delay when should this operation time out?
1600 * @param wfd write file-descriptor
1601 * @param task main function of the task
1602 * @param task_cls closure of @a task
1603 * @return unique task identifier for the job
1604 * only valid until @a task is started!
1606 struct GNUNET_SCHEDULER_Task *
1607 GNUNET_SCHEDULER_add_write_net (struct GNUNET_TIME_Relative delay,
1608 struct GNUNET_NETWORK_Handle *wfd,
1609 GNUNET_SCHEDULER_TaskCallback task,
1612 return GNUNET_SCHEDULER_add_net_with_priority (delay,
1613 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1615 GNUNET_NO, GNUNET_YES,
1620 * Schedule a new task to be run with a specified delay or when the
1621 * specified file descriptor is ready. The delay can be
1622 * used as a timeout on the socket being ready. The task will be
1623 * scheduled for execution once either the delay has expired or the
1624 * socket operation is ready.
1626 * @param delay when should this operation time out?
1627 * @param priority priority of the task
1628 * @param fd file-descriptor
1629 * @param on_read whether to poll the file-descriptor for readability
1630 * @param on_write whether to poll the file-descriptor for writability
1631 * @param task main function of the task
1632 * @param task_cls closure of task
1633 * @return unique task identifier for the job
1634 * only valid until "task" is started!
1636 struct GNUNET_SCHEDULER_Task *
1637 GNUNET_SCHEDULER_add_net_with_priority (struct GNUNET_TIME_Relative delay,
1638 enum GNUNET_SCHEDULER_Priority priority,
1639 struct GNUNET_NETWORK_Handle *fd,
1642 GNUNET_SCHEDULER_TaskCallback task,
1646 struct GNUNET_NETWORK_FDSet *s;
1647 struct GNUNET_SCHEDULER_Task * ret;
1649 GNUNET_assert (NULL != fd);
1650 s = GNUNET_NETWORK_fdset_create ();
1651 GNUNET_NETWORK_fdset_set (s, fd);
1652 ret = GNUNET_SCHEDULER_add_select (
1655 on_write ? s : NULL,
1657 GNUNET_NETWORK_fdset_destroy (s);
1660 GNUNET_assert (on_read || on_write);
1661 GNUNET_assert (GNUNET_NETWORK_get_fd (fd) >= 0);
1662 return add_without_sets (delay, priority,
1663 on_read ? fd : NULL,
1664 on_write ? fd : NULL,
1673 * Schedule a new task to be run with a specified delay or when the
1674 * specified file descriptor is ready for reading. The delay can be
1675 * used as a timeout on the socket being ready. The task will be
1676 * scheduled for execution once either the delay has expired or the
1677 * socket operation is ready. It will be run with the DEFAULT priority.
1679 * @param delay when should this operation time out?
1680 * @param rfd read file-descriptor
1681 * @param task main function of the task
1682 * @param task_cls closure of @a task
1683 * @return unique task identifier for the job
1684 * only valid until @a task is started!
1686 struct GNUNET_SCHEDULER_Task *
1687 GNUNET_SCHEDULER_add_read_file (struct GNUNET_TIME_Relative delay,
1688 const struct GNUNET_DISK_FileHandle *rfd,
1689 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1691 return GNUNET_SCHEDULER_add_file_with_priority (
1692 delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1693 rfd, GNUNET_YES, GNUNET_NO,
1699 * Schedule a new task to be run with a specified delay or when the
1700 * specified file descriptor is ready for writing. The delay can be
1701 * used as a timeout on the socket being ready. The task will be
1702 * scheduled for execution once either the delay has expired or the
1703 * socket operation is ready. It will be run with the DEFAULT priority.
1705 * @param delay when should this operation time out?
1706 * @param wfd write file-descriptor
1707 * @param task main function of the task
1708 * @param task_cls closure of @a task
1709 * @return unique task identifier for the job
1710 * only valid until @a task is started!
1712 struct GNUNET_SCHEDULER_Task *
1713 GNUNET_SCHEDULER_add_write_file (struct GNUNET_TIME_Relative delay,
1714 const struct GNUNET_DISK_FileHandle *wfd,
1715 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1717 return GNUNET_SCHEDULER_add_file_with_priority (
1718 delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1719 wfd, GNUNET_NO, GNUNET_YES,
1725 * Schedule a new task to be run with a specified delay or when the
1726 * specified file descriptor is ready. The delay can be
1727 * used as a timeout on the socket being ready. The task will be
1728 * scheduled for execution once either the delay has expired or the
1729 * socket operation is ready.
1731 * @param delay when should this operation time out?
1732 * @param priority priority of the task
1733 * @param fd file-descriptor
1734 * @param on_read whether to poll the file-descriptor for readability
1735 * @param on_write whether to poll the file-descriptor for writability
1736 * @param task main function of the task
1737 * @param task_cls closure of @a task
1738 * @return unique task identifier for the job
1739 * only valid until @a task is started!
1741 struct GNUNET_SCHEDULER_Task *
1742 GNUNET_SCHEDULER_add_file_with_priority (struct GNUNET_TIME_Relative delay,
1743 enum GNUNET_SCHEDULER_Priority priority,
1744 const struct GNUNET_DISK_FileHandle *fd,
1745 int on_read, int on_write,
1746 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1749 struct GNUNET_NETWORK_FDSet *s;
1750 struct GNUNET_SCHEDULER_Task * ret;
1752 GNUNET_assert (NULL != fd);
1753 s = GNUNET_NETWORK_fdset_create ();
1754 GNUNET_NETWORK_fdset_handle_set (s, fd);
1755 ret = GNUNET_SCHEDULER_add_select (
1758 on_write ? s : NULL,
1760 GNUNET_NETWORK_fdset_destroy (s);
1763 GNUNET_assert (on_read || on_write);
1764 GNUNET_assert(fd->fd >= 0);
1765 return add_without_sets (delay, priority,
1768 on_read ? fd : NULL,
1769 on_write ? fd : NULL,
1776 * Schedule a new task to be run with a specified delay or when any of
1777 * the specified file descriptor sets is ready. The delay can be used
1778 * as a timeout on the socket(s) being ready. The task will be
1779 * scheduled for execution once either the delay has expired or any of
1780 * the socket operations is ready. This is the most general
1781 * function of the "add" family. Note that the "prerequisite_task"
1782 * must be satisfied in addition to any of the other conditions. In
1783 * other words, the task will be started when
1785 * (prerequisite-run)
1788 * || any-ws-ready) )
1791 * @param prio how important is this task?
1792 * @param delay how long should we wait?
1793 * @param rs set of file descriptors we want to read (can be NULL)
1794 * @param ws set of file descriptors we want to write (can be NULL)
1795 * @param task main function of the task
1796 * @param task_cls closure of @a task
1797 * @return unique task identifier for the job
1798 * only valid until @a task is started!
1800 struct GNUNET_SCHEDULER_Task *
1801 GNUNET_SCHEDULER_add_select (enum GNUNET_SCHEDULER_Priority prio,
1802 struct GNUNET_TIME_Relative delay,
1803 const struct GNUNET_NETWORK_FDSet *rs,
1804 const struct GNUNET_NETWORK_FDSet *ws,
1805 GNUNET_SCHEDULER_TaskCallback task,
1808 struct GNUNET_SCHEDULER_Task *t;
1810 if ( (NULL == rs) &&
1812 return GNUNET_SCHEDULER_add_delayed_with_priority (delay,
1816 GNUNET_assert (NULL != active_task);
1817 GNUNET_assert (NULL != task);
1818 t = GNUNET_new (struct GNUNET_SCHEDULER_Task);
1820 t->callback_cls = task_cls;
1825 t->read_set = GNUNET_NETWORK_fdset_create ();
1826 GNUNET_NETWORK_fdset_copy (t->read_set, rs);
1830 t->write_set = GNUNET_NETWORK_fdset_create ();
1831 GNUNET_NETWORK_fdset_copy (t->write_set, ws);
1834 t->start_time = GNUNET_TIME_absolute_get ();
1836 t->timeout = GNUNET_TIME_relative_to_absolute (delay);
1838 check_priority ((prio ==
1839 GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority :
1841 t->lifeness = current_lifeness;
1842 GNUNET_CONTAINER_DLL_insert (pending_head,
1845 scheduler_multi_function_call(t, scheduler_driver->add);
1846 max_priority_added = GNUNET_MAX (max_priority_added,
1848 LOG (GNUNET_ERROR_TYPE_DEBUG,
1857 * Function used by event-loop implementations to signal the scheduler
1858 * that a particular @a task is ready due to an event of type @a et.
1860 * This function will then queue the task to notify the application
1861 * that the task is ready (with the respective priority).
1863 * @param task the task that is ready, NULL for wake up calls
1864 * @param et information about why the task is ready
1867 GNUNET_SCHEDULER_task_ready (struct GNUNET_SCHEDULER_Task *task,
1868 enum GNUNET_SCHEDULER_EventType et)
1870 enum GNUNET_SCHEDULER_Reason reason;
1871 struct GNUNET_TIME_Absolute now;
1873 now = GNUNET_TIME_absolute_get ();
1874 reason = task->reason;
1875 if (now.abs_value_us >= task->timeout.abs_value_us)
1876 reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
1877 if ( (0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
1878 (0 != (GNUNET_SCHEDULER_ET_IN & et)) )
1879 reason |= GNUNET_SCHEDULER_REASON_READ_READY;
1880 if ( (0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
1881 (0 != (GNUNET_SCHEDULER_ET_OUT & et)) )
1882 reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
1883 reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
1884 task->reason = reason;
1885 task->fds = &task->fdx;
1888 queue_ready_task (task);
1893 * Function called by the driver to tell the scheduler to run some of
1894 * the tasks that are ready. This function may return even though
1895 * there are tasks left to run just to give other tasks a chance as
1896 * well. If we return #GNUNET_YES, the driver should call this
1897 * function again as soon as possible, while if we return #GNUNET_NO
1898 * it must block until the operating system has more work as the
1899 * scheduler has no more work to do right now.
1901 * @param sh scheduler handle that was given to the `loop`
1902 * @return #GNUNET_OK if there are more tasks that are ready,
1903 * and thus we would like to run more (yield to avoid
1904 * blocking other activities for too long)
1905 * #GNUNET_NO if we are done running tasks (yield to block)
1906 * #GNUNET_SYSERR on error
1909 GNUNET_SCHEDULER_run_from_driver (struct GNUNET_SCHEDULER_Handle *sh)
1911 enum GNUNET_SCHEDULER_Priority p;
1912 struct GNUNET_SCHEDULER_Task *pos;
1913 struct GNUNET_TIME_Absolute now;
1915 /* check for tasks that reached the timeout! */
1916 now = GNUNET_TIME_absolute_get ();
1917 while (NULL != (pos = pending_timeout_head))
1919 if (now.abs_value_us >= pos->timeout.abs_value_us)
1920 pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
1921 if (0 == pos->reason)
1923 GNUNET_CONTAINER_DLL_remove (pending_timeout_head,
1924 pending_timeout_tail,
1927 if (pending_timeout_last == pos)
1928 pending_timeout_last = NULL;
1930 scheduler_driver->set_wakeup(scheduler_driver->cls,pending_timeout_head->timeout);
1932 queue_ready_task (pos);
1935 if (0 == ready_count)
1938 /* find out which task priority level we are going to
1939 process this time */
1940 max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
1941 GNUNET_assert (NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
1942 /* yes, p>0 is correct, 0 is "KEEP" which should
1943 * always be an empty queue (see assertion)! */
1944 for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
1946 pos = ready_head[p];
1950 GNUNET_assert (NULL != pos); /* ready_count wrong? */
1952 /* process all tasks at this priority level, then yield */
1953 while (NULL != (pos = ready_head[p]))
1955 GNUNET_CONTAINER_DLL_remove (ready_head[p],
1959 current_priority = pos->priority;
1960 current_lifeness = pos->lifeness;
1963 if (GNUNET_TIME_absolute_get_duration (pos->start_time).rel_value_us >
1964 DELAY_THRESHOLD.rel_value_us)
1966 LOG (GNUNET_ERROR_TYPE_DEBUG,
1967 "Task %p took %s to be scheduled\n",
1969 GNUNET_STRINGS_relative_time_to_string (GNUNET_TIME_absolute_get_duration (pos->start_time),
1973 tc.reason = pos->reason;
1974 GNUNET_NETWORK_fdset_zero (sh->rs);
1975 GNUNET_NETWORK_fdset_zero (sh->ws);
1976 tc.fds_len = pos->fds_len;
1978 tc.read_ready = (NULL == pos->read_set) ? sh->rs : pos->read_set;
1979 if ( (-1 != pos->read_fd) &&
1980 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_READ_READY)) )
1981 GNUNET_NETWORK_fdset_set_native (sh->rs,
1983 tc.write_ready = (NULL == pos->write_set) ? sh->ws : pos->write_set;
1984 if ((-1 != pos->write_fd) &&
1985 (0 != (pos->reason & GNUNET_SCHEDULER_REASON_WRITE_READY)))
1986 GNUNET_NETWORK_fdset_set_native (sh->ws,
1988 LOG (GNUNET_ERROR_TYPE_DEBUG,
1989 "Running task: %p\n",
1991 pos->callback (pos->callback_cls);
1993 dump_backtrace (pos);
1997 if (0 == ready_count)
2004 * Initialize and run scheduler. This function will return when all
2005 * tasks have completed. On systems with signals, receiving a SIGTERM
2006 * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown
2007 * to be run after the active task is complete. As a result, SIGTERM
2008 * causes all shutdown tasks to be scheduled with reason
2009 * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
2010 * afterwards will execute normally!). Note that any particular
2011 * signal will only shut down one scheduler; applications should
2012 * always only create a single scheduler.
2014 * @param driver drive to use for the event loop
2015 * @param task task to run first (and immediately)
2016 * @param task_cls closure of @a task
2017 * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
2020 GNUNET_SCHEDULER_run_with_driver (const struct GNUNET_SCHEDULER_Driver *driver,
2021 GNUNET_SCHEDULER_TaskCallback task,
2025 struct GNUNET_SCHEDULER_Handle sh;
2026 struct GNUNET_SIGNAL_Context *shc_int;
2027 struct GNUNET_SIGNAL_Context *shc_term;
2028 #if (SIGTERM != GNUNET_TERM_SIG)
2029 struct GNUNET_SIGNAL_Context *shc_gterm;
2032 struct GNUNET_SIGNAL_Context *shc_quit;
2033 struct GNUNET_SIGNAL_Context *shc_hup;
2034 struct GNUNET_SIGNAL_Context *shc_pipe;
2036 struct GNUNET_SCHEDULER_Task tsk;
2037 const struct GNUNET_DISK_FileHandle *pr;
2038 scheduler_driver = driver;
2040 /* general set-up */
2041 GNUNET_assert (NULL == active_task);
2042 GNUNET_assert (NULL == shutdown_pipe_handle);
2043 shutdown_pipe_handle = GNUNET_DISK_pipe (GNUNET_NO,
2047 GNUNET_assert (NULL != shutdown_pipe_handle);
2048 pr = GNUNET_DISK_pipe_handle (shutdown_pipe_handle,
2049 GNUNET_DISK_PIPE_END_READ);
2050 GNUNET_assert (NULL != pr);
2053 /* install signal handlers */
2054 LOG (GNUNET_ERROR_TYPE_DEBUG,
2055 "Registering signal handlers\n");
2056 shc_int = GNUNET_SIGNAL_handler_install (SIGINT,
2057 &sighandler_shutdown);
2058 shc_term = GNUNET_SIGNAL_handler_install (SIGTERM,
2059 &sighandler_shutdown);
2060 #if (SIGTERM != GNUNET_TERM_SIG)
2061 shc_gterm = GNUNET_SIGNAL_handler_install (GNUNET_TERM_SIG,
2062 &sighandler_shutdown);
2065 shc_pipe = GNUNET_SIGNAL_handler_install (SIGPIPE,
2067 shc_quit = GNUNET_SIGNAL_handler_install (SIGQUIT,
2068 &sighandler_shutdown);
2069 shc_hup = GNUNET_SIGNAL_handler_install (SIGHUP,
2070 &sighandler_shutdown);
2073 /* Setup initial tasks */
2074 current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;
2075 current_lifeness = GNUNET_YES;
2081 GNUNET_SCHEDULER_add_with_reason_and_priority (task,
2083 GNUNET_SCHEDULER_REASON_STARTUP,
2084 GNUNET_SCHEDULER_PRIORITY_DEFAULT);
2085 GNUNET_SCHEDULER_add_now_with_lifeness (GNUNET_NO,
2086 &GNUNET_OS_install_parent_control_handler,
2089 driver->set_wakeup (driver->cls,
2090 GNUNET_TIME_absolute_get ());
2092 /* begin main event loop */
2093 sh.rs = GNUNET_NETWORK_fdset_create ();
2094 sh.ws = GNUNET_NETWORK_fdset_create ();
2095 GNUNET_NETWORK_fdset_handle_set (sh.rs, pr);
2097 ret = driver->loop (driver->cls,
2099 GNUNET_NETWORK_fdset_destroy (sh.rs);
2100 GNUNET_NETWORK_fdset_destroy (sh.ws);
2102 /* uninstall signal handlers */
2103 GNUNET_SIGNAL_handler_uninstall (shc_int);
2104 GNUNET_SIGNAL_handler_uninstall (shc_term);
2105 #if (SIGTERM != GNUNET_TERM_SIG)
2106 GNUNET_SIGNAL_handler_uninstall (shc_gterm);
2109 GNUNET_SIGNAL_handler_uninstall (shc_pipe);
2110 GNUNET_SIGNAL_handler_uninstall (shc_quit);
2111 GNUNET_SIGNAL_handler_uninstall (shc_hup);
2113 GNUNET_DISK_pipe_close (shutdown_pipe_handle);
2114 shutdown_pipe_handle = NULL;
2119 select_add(void *cls,
2120 struct GNUNET_SCHEDULER_Task *task,
2121 struct GNUNET_SCHEDULER_FdInfo *fdi)
2128 select_del(void *cls,
2129 struct GNUNET_SCHEDULER_Task *task,
2130 struct GNUNET_SCHEDULER_FdInfo *fdi)
2137 select_loop(void *cls,
2138 struct GNUNET_SCHEDULER_Handle *sh)
2140 return while_live(sh->rs, sh->ws);
2145 select_set_wakeup(void *cls,
2146 struct GNUNET_TIME_Absolute dt)
2153 * Obtain the driver for using select() as the event loop.
2155 * @return NULL on error
2157 const struct GNUNET_SCHEDULER_Driver *
2158 GNUNET_SCHEDULER_driver_select ()
2161 struct GNUNET_SCHEDULER_Driver *select_driver;
2163 select_driver = GNUNET_new (struct GNUNET_SCHEDULER_Driver);
2165 select_driver->loop = &select_loop;
2166 select_driver->add = &select_add;
2167 select_driver->del = &select_del;
2168 select_driver->set_wakeup = &select_set_wakeup;
2171 return select_driver;
2175 /* end of scheduler.c */