2 This file is part of GNUnet
3 Copyright (C) 2009-2017 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
15 You should have received a copy of the GNU Affero General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 SPDX-License-Identifier: AGPL3.0-or-later
21 * @file util/scheduler.c
22 * @brief schedule computations using continuation passing style
23 * @author Christian Grothoff
26 #include "gnunet_util_lib.h"
31 #define LOG(kind, ...) GNUNET_log_from(kind, "util-scheduler", __VA_ARGS__)
33 #define LOG_STRERROR(kind, syscall) GNUNET_log_from_strerror(kind, "util-scheduler", syscall)
40 * Use lsof to generate file descriptor reports on select error?
41 * (turn off for stable releases).
43 #define USE_LSOF GNUNET_NO
46 * Obtain trace information for all scheduler calls that schedule tasks.
48 #define EXECINFO GNUNET_NO
51 * Check each file descriptor before adding
53 #define DEBUG_FDS GNUNET_NO
56 * Depth of the traces collected via EXECINFO.
58 #define MAX_TRACE_DEPTH 50
62 * Should we figure out which tasks are delayed for a while
63 * before they are run? (Consider using in combination with EXECINFO).
65 #define PROFILE_DELAYS GNUNET_NO
68 * Task that were in the queue for longer than this are reported if
69 * PROFILE_DELAYS is active.
71 #define DELAY_THRESHOLD GNUNET_TIME_UNIT_SECONDS
75 * Argument to be passed from the driver to
76 * #GNUNET_SCHEDULER_do_work(). Contains the
77 * scheduler's internal state.
79 struct GNUNET_SCHEDULER_Handle {
81 * Passed here to avoid constantly allocating/deallocating
82 * this element, but generally we want to get rid of this.
85 struct GNUNET_NETWORK_FDSet *rs;
88 * Passed here to avoid constantly allocating/deallocating
89 * this element, but generally we want to get rid of this.
92 struct GNUNET_NETWORK_FDSet *ws;
95 * context of the SIGINT handler
97 struct GNUNET_SIGNAL_Context *shc_int;
100 * context of the SIGTERM handler
102 struct GNUNET_SIGNAL_Context *shc_term;
104 #if (SIGTERM != GNUNET_TERM_SIG)
106 * context of the TERM_SIG handler
108 struct GNUNET_SIGNAL_Context *shc_gterm;
113 * context of the SIGQUIT handler
115 struct GNUNET_SIGNAL_Context *shc_quit;
118 * context of the SIGHUP handler
120 struct GNUNET_SIGNAL_Context *shc_hup;
123 * context of hte SIGPIPE handler
125 struct GNUNET_SIGNAL_Context *shc_pipe;
131 * Entry in list of pending tasks.
133 struct GNUNET_SCHEDULER_Task {
135 * This is a linked list.
137 struct GNUNET_SCHEDULER_Task *next;
140 * This is a linked list.
142 struct GNUNET_SCHEDULER_Task *prev;
145 * Function to run when ready.
147 GNUNET_SCHEDULER_TaskCallback callback;
150 * Closure for the @e callback.
155 * Information about which FDs are ready for this task (and why).
157 struct GNUNET_SCHEDULER_FdInfo *fds;
160 * Storage location used for @e fds if we want to avoid
161 * a separate malloc() call in the common case that this
162 * task is only about a single FD.
164 struct GNUNET_SCHEDULER_FdInfo fdx;
167 * Size of the @e fds array.
169 unsigned int fds_len;
172 * Do we own the network and file handles referenced by the FdInfo
173 * structs in the fds array. This will only be GNUNET_YES if the
174 * task was created by the #GNUNET_SCHEDULER_add_select function.
179 * Absolute timeout value for the task, or
180 * #GNUNET_TIME_UNIT_FOREVER_ABS for "no timeout".
182 struct GNUNET_TIME_Absolute timeout;
186 * When was the task scheduled?
188 struct GNUNET_TIME_Absolute start_time;
192 * Why is the task ready? Set after task is added to ready queue.
193 * Initially set to zero. All reasons that have already been
194 * satisfied (i.e. read or write ready) will be set over time.
196 enum GNUNET_SCHEDULER_Reason reason;
201 enum GNUNET_SCHEDULER_Priority priority;
204 * Set if we only wait for reading from a single FD, otherwise -1.
209 * Set if we only wait for writing to a single FD, otherwise -1.
214 * Should the existence of this task in the queue be counted as
215 * reason to not shutdown the scheduler?
220 * Is this task run on shutdown?
225 * Is this task in the ready list?
231 * Array of strings which make up a backtrace from the point when this
232 * task was scheduled (essentially, who scheduled the task?)
234 char **backtrace_strings;
237 * Size of the backtrace_strings array
239 int num_backtrace_strings;
243 * Asynchronous scope of the task that scheduled this scope,
245 struct GNUNET_AsyncScopeSave scope;
250 * A struct representing an event the select driver is waiting for
253 struct Scheduled *prev;
255 struct Scheduled *next;
258 * the task, the event is related to
260 struct GNUNET_SCHEDULER_Task *task;
263 * information about the network socket / file descriptor where
264 * the event is expected to occur
266 struct GNUNET_SCHEDULER_FdInfo *fdi;
269 * the event types (multiple event types can be ORed) the select
270 * driver is expected to wait for
272 enum GNUNET_SCHEDULER_EventType et;
277 * Driver context used by GNUNET_SCHEDULER_run
279 struct DriverContext {
281 * the head of a DLL containing information about the events the
282 * select driver is waiting for
284 struct Scheduled *scheduled_head;
287 * the tail of a DLL containing information about the events the
288 * select driver is waiting for
290 struct Scheduled *scheduled_tail;
293 * the time when the select driver will wake up again (after
296 struct GNUNET_TIME_Absolute timeout;
301 * The driver used for the event loop. Will be handed over to
302 * the scheduler in #GNUNET_SCHEDULER_do_work(), persisted
303 * there in this variable for later use in functions like
304 * #GNUNET_SCHEDULER_add_select(), #add_without_sets() and
305 * #GNUNET_SCHEDULER_cancel().
307 static const struct GNUNET_SCHEDULER_Driver *scheduler_driver;
310 * Head of list of tasks waiting for an event.
312 static struct GNUNET_SCHEDULER_Task *pending_head;
315 * Tail of list of tasks waiting for an event.
317 static struct GNUNET_SCHEDULER_Task *pending_tail;
320 * Head of list of tasks waiting for shutdown.
322 static struct GNUNET_SCHEDULER_Task *shutdown_head;
325 * Tail of list of tasks waiting for shutdown.
327 static struct GNUNET_SCHEDULER_Task *shutdown_tail;
330 * List of tasks waiting ONLY for a timeout event.
331 * Sorted by timeout (earliest first). Used so that
332 * we do not traverse the list of these tasks when
333 * building select sets (we just look at the head
334 * to determine the respective timeout ONCE).
336 static struct GNUNET_SCHEDULER_Task *pending_timeout_head;
339 * List of tasks waiting ONLY for a timeout event.
340 * Sorted by timeout (earliest first). Used so that
341 * we do not traverse the list of these tasks when
342 * building select sets (we just look at the head
343 * to determine the respective timeout ONCE).
345 static struct GNUNET_SCHEDULER_Task *pending_timeout_tail;
348 * Last inserted task waiting ONLY for a timeout event.
349 * Used to (heuristically) speed up insertion.
351 static struct GNUNET_SCHEDULER_Task *pending_timeout_last;
354 * ID of the task that is running right now.
356 static struct GNUNET_SCHEDULER_Task *active_task;
359 * Head of list of tasks ready to run right now, grouped by importance.
361 static struct GNUNET_SCHEDULER_Task *ready_head[GNUNET_SCHEDULER_PRIORITY_COUNT];
364 * Tail of list of tasks ready to run right now, grouped by importance.
366 static struct GNUNET_SCHEDULER_Task *ready_tail[GNUNET_SCHEDULER_PRIORITY_COUNT];
369 * Task for installing parent control handlers (it might happen that the
370 * scheduler is shutdown before this task is executed, so
371 * GNUNET_SCHEDULER_shutdown must cancel it in that case)
373 static struct GNUNET_SCHEDULER_Task *install_parent_control_task;
376 * Task for reading from a pipe that signal handlers will use to initiate
379 static struct GNUNET_SCHEDULER_Task *shutdown_pipe_task;
382 * Number of tasks on the ready list.
384 static unsigned int ready_count;
387 * Priority of the task running right now. Only
388 * valid while a task is running.
390 static enum GNUNET_SCHEDULER_Priority current_priority;
393 * Priority of the highest task added in the current select
396 static enum GNUNET_SCHEDULER_Priority max_priority_added;
399 * Value of the 'lifeness' flag for the current task.
401 static int current_lifeness;
404 * Function to use as a select() in the scheduler.
405 * If NULL, we use GNUNET_NETWORK_socket_select().
407 static GNUNET_SCHEDULER_select scheduler_select;
410 * Task context of the current task.
412 static struct GNUNET_SCHEDULER_TaskContext tc;
415 * Closure for #scheduler_select.
417 static void *scheduler_select_cls;
421 * Sets the select function to use in the scheduler (scheduler_select).
423 * @param new_select new select function to use
424 * @param new_select_cls closure for @a new_select
425 * @return previously used select function, NULL for default
428 GNUNET_SCHEDULER_set_select(GNUNET_SCHEDULER_select new_select,
429 void *new_select_cls)
431 scheduler_select = new_select;
432 scheduler_select_cls = new_select_cls;
437 * Check that the given priority is legal (and return it).
439 * @param p priority value to check
440 * @return p on success, 0 on error
442 static enum GNUNET_SCHEDULER_Priority
443 check_priority(enum GNUNET_SCHEDULER_Priority p)
445 if ((p >= 0) && (p < GNUNET_SCHEDULER_PRIORITY_COUNT))
448 return 0; /* make compiler happy */
453 * chooses the nearest timeout from all pending tasks, to be used
454 * to tell the driver the next wakeup time (using its set_wakeup
457 struct GNUNET_TIME_Absolute
460 struct GNUNET_SCHEDULER_Task *pos;
461 struct GNUNET_TIME_Absolute now;
462 struct GNUNET_TIME_Absolute timeout;
464 pos = pending_timeout_head;
465 now = GNUNET_TIME_absolute_get();
466 timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
469 if (0 != pos->reason)
475 timeout = pos->timeout;
478 for (pos = pending_head; NULL != pos; pos = pos->next)
480 if (0 != pos->reason)
484 else if ((pos->timeout.abs_value_us != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us) &&
485 (timeout.abs_value_us > pos->timeout.abs_value_us))
487 timeout = pos->timeout;
495 * Put a task that is ready for execution into the ready queue.
497 * @param task task ready for execution
500 queue_ready_task(struct GNUNET_SCHEDULER_Task *task)
502 enum GNUNET_SCHEDULER_Priority p = check_priority(task->priority);
504 GNUNET_CONTAINER_DLL_insert(ready_head[p],
507 task->in_ready_list = GNUNET_YES;
513 * Request the shutdown of a scheduler. Marks all tasks
514 * awaiting shutdown as ready. Note that tasks
515 * scheduled with #GNUNET_SCHEDULER_add_shutdown() AFTER this call
516 * will be delayed until the next shutdown signal.
519 GNUNET_SCHEDULER_shutdown()
521 struct GNUNET_SCHEDULER_Task *pos;
523 LOG(GNUNET_ERROR_TYPE_DEBUG,
524 "GNUNET_SCHEDULER_shutdown\n");
525 if (NULL != install_parent_control_task)
527 GNUNET_SCHEDULER_cancel(install_parent_control_task);
528 install_parent_control_task = NULL;
530 if (NULL != shutdown_pipe_task)
532 GNUNET_SCHEDULER_cancel(shutdown_pipe_task);
533 shutdown_pipe_task = NULL;
535 while (NULL != (pos = shutdown_head))
537 GNUNET_CONTAINER_DLL_remove(shutdown_head,
540 pos->reason |= GNUNET_SCHEDULER_REASON_SHUTDOWN;
541 queue_ready_task(pos);
547 * Output stack trace of task @a t.
549 * @param t task to dump stack trace of
552 dump_backtrace(struct GNUNET_SCHEDULER_Task *t)
555 for (unsigned int i = 0; i < t->num_backtrace_strings; i++)
556 LOG(GNUNET_ERROR_TYPE_WARNING,
557 "Task %p trace %u: %s\n",
560 t->backtrace_strings[i]);
568 * Destroy a task (release associated resources)
570 * @param t task to destroy
573 destroy_task(struct GNUNET_SCHEDULER_Task *t)
577 LOG(GNUNET_ERROR_TYPE_DEBUG,
578 "destroying task %p\n",
581 if (GNUNET_YES == t->own_handles)
583 for (i = 0; i != t->fds_len; ++i)
585 const struct GNUNET_NETWORK_Handle *fd = t->fds[i].fd;
586 const struct GNUNET_DISK_FileHandle *fh = t->fds[i].fh;
589 GNUNET_NETWORK_socket_free_memory_only_((struct GNUNET_NETWORK_Handle *)fd);
593 // FIXME: on WIN32 this is not enough! A function
594 // GNUNET_DISK_file_free_memory_only would be nice
595 GNUNET_free((void *)fh);
601 GNUNET_array_grow(t->fds, t->fds_len, 0);
604 GNUNET_free(t->backtrace_strings);
611 * Pipe used to communicate shutdown via signal.
613 static struct GNUNET_DISK_PipeHandle *shutdown_pipe_handle;
616 * Process ID of this process at the time we installed the various
622 * Signal handler called for SIGPIPE.
634 // * Wait for a short time.
635 // * Sleeps for @a ms ms (as that should be long enough for virtually all
636 // * modern systems to context switch and allow another process to do
637 // * some 'real' work).
639 // * @param ms how many ms to wait
642 //short_wait (unsigned int ms)
644 // struct GNUNET_TIME_Relative timeout;
646 // timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, ms);
647 // (void) GNUNET_NETWORK_socket_select (NULL, NULL, NULL, timeout);
652 * Signal handler called for signals that should cause us to shutdown.
655 sighandler_shutdown()
658 int old_errno = errno; /* backup errno */
660 if (getpid() != my_pid)
661 _exit(1); /* we have fork'ed since the signal handler was created,
662 * ignore the signal, see https://gnunet.org/vfork discussion */
663 GNUNET_DISK_file_write(GNUNET_DISK_pipe_handle
664 (shutdown_pipe_handle, GNUNET_DISK_PIPE_END_WRITE),
671 shutdown_if_no_lifeness()
673 struct GNUNET_SCHEDULER_Task *t;
677 for (t = pending_head; NULL != t; t = t->next)
678 if (GNUNET_YES == t->lifeness)
680 for (t = shutdown_head; NULL != t; t = t->next)
681 if (GNUNET_YES == t->lifeness)
683 for (t = pending_timeout_head; NULL != t; t = t->next)
684 if (GNUNET_YES == t->lifeness)
687 GNUNET_SCHEDULER_shutdown();
692 select_loop(struct GNUNET_SCHEDULER_Handle *sh,
693 struct DriverContext *context);
697 * Initialize and run scheduler. This function will return when all
698 * tasks have completed. On systems with signals, receiving a SIGTERM
699 * (and other similar signals) will cause #GNUNET_SCHEDULER_shutdown()
700 * to be run after the active task is complete. As a result, SIGTERM
701 * causes all active tasks to be scheduled with reason
702 * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added
703 * afterwards will execute normally!). Note that any particular signal
704 * will only shut down one scheduler; applications should always only
705 * create a single scheduler.
707 * @param task task to run immediately
708 * @param task_cls closure of @a task
711 GNUNET_SCHEDULER_run(GNUNET_SCHEDULER_TaskCallback task,
714 struct GNUNET_SCHEDULER_Handle *sh;
715 struct GNUNET_SCHEDULER_Driver *driver;
716 struct DriverContext context = { .scheduled_head = NULL,
717 .scheduled_tail = NULL,
718 .timeout = GNUNET_TIME_absolute_get() };
720 driver = GNUNET_SCHEDULER_driver_select();
721 driver->cls = &context;
722 sh = GNUNET_SCHEDULER_driver_init(driver);
723 GNUNET_SCHEDULER_add_with_reason_and_priority(task,
725 GNUNET_SCHEDULER_REASON_STARTUP,
726 GNUNET_SCHEDULER_PRIORITY_DEFAULT);
729 GNUNET_SCHEDULER_driver_done(sh);
735 * Obtain the task context, giving the reason why the current task was
738 * @return current tasks' scheduler context
740 const struct GNUNET_SCHEDULER_TaskContext *
741 GNUNET_SCHEDULER_get_task_context()
743 GNUNET_assert(NULL != active_task);
749 * Get information about the current load of this scheduler. Use this
750 * function to determine if an elective task should be added or simply
751 * dropped (if the decision should be made based on the number of
752 * tasks ready to run).
754 * @param p priority level to look at
755 * @return number of tasks pending right now
758 GNUNET_SCHEDULER_get_load(enum GNUNET_SCHEDULER_Priority p)
760 struct GNUNET_SCHEDULER_Task *pos;
763 GNUNET_assert(NULL != active_task);
764 if (p == GNUNET_SCHEDULER_PRIORITY_COUNT)
766 if (p == GNUNET_SCHEDULER_PRIORITY_KEEP)
767 p = current_priority;
769 for (pos = ready_head[check_priority(p)]; NULL != pos; pos = pos->next)
776 init_fd_info(struct GNUNET_SCHEDULER_Task *t,
777 const struct GNUNET_NETWORK_Handle *const *read_nh,
778 unsigned int read_nh_len,
779 const struct GNUNET_NETWORK_Handle *const *write_nh,
780 unsigned int write_nh_len,
781 const struct GNUNET_DISK_FileHandle *const *read_fh,
782 unsigned int read_fh_len,
783 const struct GNUNET_DISK_FileHandle *const *write_fh,
784 unsigned int write_fh_len)
786 // FIXME: if we have exactly two network handles / exactly two file handles
787 // and they are equal, we can make one FdInfo with both
788 // GNUNET_SCHEDULER_ET_IN and GNUNET_SCHEDULER_ET_OUT set.
789 struct GNUNET_SCHEDULER_FdInfo *fdi;
791 t->fds_len = read_nh_len + write_nh_len + read_fh_len + write_fh_len;
796 if (1 == read_nh_len)
798 GNUNET_assert(NULL != read_nh);
799 GNUNET_assert(NULL != *read_nh);
801 fdi->et = GNUNET_SCHEDULER_ET_IN;
802 fdi->sock = GNUNET_NETWORK_get_fd(*read_nh);
803 t->read_fd = fdi->sock;
806 else if (1 == write_nh_len)
808 GNUNET_assert(NULL != write_nh);
809 GNUNET_assert(NULL != *write_nh);
811 fdi->et = GNUNET_SCHEDULER_ET_OUT;
812 fdi->sock = GNUNET_NETWORK_get_fd(*write_nh);
814 t->write_fd = fdi->sock;
816 else if (1 == read_fh_len)
818 GNUNET_assert(NULL != read_fh);
819 GNUNET_assert(NULL != *read_fh);
821 fdi->et = GNUNET_SCHEDULER_ET_IN;
822 fdi->sock = (*read_fh)->fd; // FIXME: does not work under WIN32
823 t->read_fd = fdi->sock;
828 GNUNET_assert(NULL != write_fh);
829 GNUNET_assert(NULL != *write_fh);
831 fdi->et = GNUNET_SCHEDULER_ET_OUT;
832 fdi->sock = (*write_fh)->fd; // FIXME: does not work under WIN32
834 t->write_fd = fdi->sock;
839 fdi = GNUNET_new_array(t->fds_len, struct GNUNET_SCHEDULER_FdInfo);
844 for (i = 0; i != read_nh_len; ++i)
846 fdi->fd = read_nh[i];
847 GNUNET_assert(NULL != fdi->fd);
848 fdi->et = GNUNET_SCHEDULER_ET_IN;
849 fdi->sock = GNUNET_NETWORK_get_fd(read_nh[i]);
852 for (i = 0; i != write_nh_len; ++i)
854 fdi->fd = write_nh[i];
855 GNUNET_assert(NULL != fdi->fd);
856 fdi->et = GNUNET_SCHEDULER_ET_OUT;
857 fdi->sock = GNUNET_NETWORK_get_fd(write_nh[i]);
860 for (i = 0; i != read_fh_len; ++i)
862 fdi->fh = read_fh[i];
863 GNUNET_assert(NULL != fdi->fh);
864 fdi->et = GNUNET_SCHEDULER_ET_IN;
865 fdi->sock = (read_fh[i])->fd; // FIXME: does not work under WIN32
868 for (i = 0; i != write_fh_len; ++i)
870 fdi->fh = write_fh[i];
871 GNUNET_assert(NULL != fdi->fh);
872 fdi->et = GNUNET_SCHEDULER_ET_OUT;
873 fdi->sock = (write_fh[i])->fd; // FIXME: does not work under WIN32
881 * calls the given function @a func on each FdInfo related to @a t.
882 * Optionally updates the event type field in each FdInfo after calling
886 * @param driver_func the function to call with each FdInfo contained in
888 * @param if_not_ready only call @a driver_func on FdInfos that are not
890 * @param et the event type to be set in each FdInfo after calling
891 * @a driver_func on it, or -1 if no updating not desired.
894 driver_add_multiple(struct GNUNET_SCHEDULER_Task *t)
896 struct GNUNET_SCHEDULER_FdInfo *fdi;
897 int success = GNUNET_YES;
899 for (unsigned int i = 0; i != t->fds_len; ++i)
902 success = scheduler_driver->add(scheduler_driver->cls,
905 fdi->et = GNUNET_SCHEDULER_ET_NONE;
907 if (GNUNET_YES != success)
909 LOG(GNUNET_ERROR_TYPE_ERROR,
910 "driver could not add task\n");
916 install_parent_control_handler(void *cls)
919 install_parent_control_task = NULL;
920 GNUNET_OS_install_parent_control_handler(NULL);
925 shutdown_pipe_cb(void *cls)
928 const struct GNUNET_DISK_FileHandle *pr;
931 shutdown_pipe_task = NULL;
932 pr = GNUNET_DISK_pipe_handle(shutdown_pipe_handle,
933 GNUNET_DISK_PIPE_END_READ);
934 GNUNET_assert(!GNUNET_DISK_handle_invalid(pr));
935 /* consume the signal */
936 GNUNET_DISK_file_read(pr, &c, sizeof(c));
937 /* mark all active tasks as ready due to shutdown */
938 GNUNET_SCHEDULER_shutdown();
940 GNUNET_SCHEDULER_add_read_file(GNUNET_TIME_UNIT_FOREVER_REL,
948 * Cancel the task with the specified identifier.
949 * The task must not yet have run. Only allowed to be called as long as the
950 * scheduler is running, that is one of the following conditions is met:
952 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
953 * - #GNUNET_SCHEDULER_driver_init has been run and
954 * #GNUNET_SCHEDULER_driver_done has not been called yet
956 * @param task id of the task to cancel
957 * @return original closure of the task
960 GNUNET_SCHEDULER_cancel(struct GNUNET_SCHEDULER_Task *task)
962 enum GNUNET_SCHEDULER_Priority p;
966 LOG(GNUNET_ERROR_TYPE_DEBUG,
967 "canceling task %p\n",
970 /* scheduler must be running */
971 GNUNET_assert(NULL != scheduler_driver);
972 is_fd_task = (NULL != task->fds);
975 int del_result = scheduler_driver->del(scheduler_driver->cls, task);
976 if (GNUNET_OK != del_result)
978 LOG(GNUNET_ERROR_TYPE_ERROR,
979 "driver could not delete task\n");
983 if (!task->in_ready_list)
987 GNUNET_CONTAINER_DLL_remove(pending_head,
991 else if (GNUNET_YES == task->on_shutdown)
993 GNUNET_CONTAINER_DLL_remove(shutdown_head,
999 GNUNET_CONTAINER_DLL_remove(pending_timeout_head,
1000 pending_timeout_tail,
1002 if (pending_timeout_last == task)
1003 pending_timeout_last = NULL;
1008 p = check_priority(task->priority);
1009 GNUNET_CONTAINER_DLL_remove(ready_head[p],
1014 ret = task->callback_cls;
1021 * Initialize backtrace data for task @a t
1023 * @param t task to initialize
1026 init_backtrace(struct GNUNET_SCHEDULER_Task *t)
1029 void *backtrace_array[MAX_TRACE_DEPTH];
1031 t->num_backtrace_strings
1032 = backtrace(backtrace_array, MAX_TRACE_DEPTH);
1033 t->backtrace_strings =
1034 backtrace_symbols(backtrace_array,
1035 t->num_backtrace_strings);
1044 * Continue the current execution with the given function. This is
1045 * similar to the other "add" functions except that there is no delay
1046 * and the reason code can be specified.
1048 * @param task main function of the task
1049 * @param task_cls closure for @a task
1050 * @param reason reason for task invocation
1051 * @param priority priority to use for the task
1054 GNUNET_SCHEDULER_add_with_reason_and_priority(GNUNET_SCHEDULER_TaskCallback task,
1056 enum GNUNET_SCHEDULER_Reason reason,
1057 enum GNUNET_SCHEDULER_Priority priority)
1059 struct GNUNET_SCHEDULER_Task *t;
1061 /* scheduler must be running */
1062 GNUNET_assert(NULL != scheduler_driver);
1063 GNUNET_assert(NULL != task);
1064 t = GNUNET_new(struct GNUNET_SCHEDULER_Task);
1068 t->callback_cls = task_cls;
1070 t->start_time = GNUNET_TIME_absolute_get();
1073 t->priority = check_priority(priority);
1074 t->lifeness = current_lifeness;
1075 LOG(GNUNET_ERROR_TYPE_DEBUG,
1076 "Adding continuation task %p\n",
1079 queue_ready_task(t);
1084 * Schedule a new task to be run at the specified time. The task
1085 * will be scheduled for execution at time @a at.
1087 * @param at time when the operation should run
1088 * @param priority priority to use for the task
1089 * @param task main function of the task
1090 * @param task_cls closure of @a task
1091 * @return unique task identifier for the job
1092 * only valid until @a task is started!
1094 struct GNUNET_SCHEDULER_Task *
1095 GNUNET_SCHEDULER_add_at_with_priority(struct GNUNET_TIME_Absolute at,
1096 enum GNUNET_SCHEDULER_Priority priority,
1097 GNUNET_SCHEDULER_TaskCallback task,
1100 struct GNUNET_SCHEDULER_Task *t;
1101 struct GNUNET_SCHEDULER_Task *pos;
1102 struct GNUNET_SCHEDULER_Task *prev;
1104 /* scheduler must be running */
1105 GNUNET_assert(NULL != scheduler_driver);
1106 GNUNET_assert(NULL != task);
1107 t = GNUNET_new(struct GNUNET_SCHEDULER_Task);
1108 GNUNET_async_scope_get(&t->scope);
1110 t->callback_cls = task_cls;
1114 t->start_time = GNUNET_TIME_absolute_get();
1117 t->priority = check_priority(priority);
1118 t->lifeness = current_lifeness;
1119 /* try tail first (optimization in case we are
1120 * appending to a long list of tasks with timeouts) */
1121 if ((NULL == pending_timeout_head) ||
1122 (at.abs_value_us < pending_timeout_head->timeout.abs_value_us))
1124 GNUNET_CONTAINER_DLL_insert(pending_timeout_head,
1125 pending_timeout_tail,
1130 /* first move from heuristic start backwards to before start time */
1131 prev = pending_timeout_last;
1132 while ((NULL != prev) &&
1133 (prev->timeout.abs_value_us > t->timeout.abs_value_us))
1135 /* now, move from heuristic start (or head of list) forward to insertion point */
1137 pos = pending_timeout_head;
1140 while ((NULL != pos) && (pos->timeout.abs_value_us <= t->timeout.abs_value_us))
1145 GNUNET_CONTAINER_DLL_insert_after(pending_timeout_head,
1146 pending_timeout_tail,
1150 /* finally, update heuristic insertion point to last insertion... */
1151 pending_timeout_last = t;
1153 LOG(GNUNET_ERROR_TYPE_DEBUG,
1162 * Schedule a new task to be run with a specified delay. The task
1163 * will be scheduled for execution once the delay has expired.
1165 * @param delay when should this operation time out?
1166 * @param priority priority to use for the task
1167 * @param task main function of the task
1168 * @param task_cls closure of @a task
1169 * @return unique task identifier for the job
1170 * only valid until @a task is started!
1172 struct GNUNET_SCHEDULER_Task *
1173 GNUNET_SCHEDULER_add_delayed_with_priority(struct GNUNET_TIME_Relative delay,
1174 enum GNUNET_SCHEDULER_Priority priority,
1175 GNUNET_SCHEDULER_TaskCallback task,
1178 return GNUNET_SCHEDULER_add_at_with_priority(GNUNET_TIME_relative_to_absolute(delay),
1186 * Schedule a new task to be run with a specified priority.
1188 * @param prio how important is the new task?
1189 * @param task main function of the task
1190 * @param task_cls closure of @a task
1191 * @return unique task identifier for the job
1192 * only valid until @a task is started!
1194 struct GNUNET_SCHEDULER_Task *
1195 GNUNET_SCHEDULER_add_with_priority(enum GNUNET_SCHEDULER_Priority prio,
1196 GNUNET_SCHEDULER_TaskCallback task,
1199 return GNUNET_SCHEDULER_add_delayed_with_priority(GNUNET_TIME_UNIT_ZERO,
1207 * Schedule a new task to be run at the specified time. The task
1208 * will be scheduled for execution once specified time has been
1209 * reached. It will be run with the DEFAULT priority.
1211 * @param at time at which this operation should run
1212 * @param task main function of the task
1213 * @param task_cls closure of @a task
1214 * @return unique task identifier for the job
1215 * only valid until @a task is started!
1217 struct GNUNET_SCHEDULER_Task *
1218 GNUNET_SCHEDULER_add_at(struct GNUNET_TIME_Absolute at,
1219 GNUNET_SCHEDULER_TaskCallback task,
1222 return GNUNET_SCHEDULER_add_at_with_priority(at,
1223 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1230 * Schedule a new task to be run with a specified delay. The task
1231 * will be scheduled for execution once the delay has expired. It
1232 * will be run with the DEFAULT priority.
1234 * @param delay when should this operation time out?
1235 * @param task main function of the task
1236 * @param task_cls closure of @a task
1237 * @return unique task identifier for the job
1238 * only valid until @a task is started!
1240 struct GNUNET_SCHEDULER_Task *
1241 GNUNET_SCHEDULER_add_delayed(struct GNUNET_TIME_Relative delay,
1242 GNUNET_SCHEDULER_TaskCallback task,
1245 return GNUNET_SCHEDULER_add_delayed_with_priority(delay,
1246 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1253 * Schedule a new task to be run as soon as possible. Note that this
1254 * does not guarantee that this will be the next task that is being
1255 * run, as other tasks with higher priority (or that are already ready
1256 * to run) might get to run first. Just as with delays, clients must
1257 * not rely on any particular order of execution between tasks
1258 * scheduled concurrently.
1260 * The task will be run with the DEFAULT priority.
1262 * @param task main function of the task
1263 * @param task_cls closure of @a task
1264 * @return unique task identifier for the job
1265 * only valid until @a task is started!
1267 struct GNUNET_SCHEDULER_Task *
1268 GNUNET_SCHEDULER_add_now(GNUNET_SCHEDULER_TaskCallback task,
1271 return GNUNET_SCHEDULER_add_delayed(GNUNET_TIME_UNIT_ZERO,
1278 * Schedule a new task to be run on shutdown, that is when a CTRL-C
1279 * signal is received, or when #GNUNET_SCHEDULER_shutdown() is being
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_shutdown(GNUNET_SCHEDULER_TaskCallback task,
1291 struct GNUNET_SCHEDULER_Task *t;
1293 /* scheduler must be running */
1294 GNUNET_assert(NULL != scheduler_driver);
1295 GNUNET_assert(NULL != task);
1296 t = GNUNET_new(struct GNUNET_SCHEDULER_Task);
1297 GNUNET_async_scope_get(&t->scope);
1299 t->callback_cls = task_cls;
1303 t->start_time = GNUNET_TIME_absolute_get();
1305 t->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
1306 t->priority = GNUNET_SCHEDULER_PRIORITY_SHUTDOWN;
1307 t->on_shutdown = GNUNET_YES;
1308 t->lifeness = GNUNET_NO;
1309 GNUNET_CONTAINER_DLL_insert(shutdown_head,
1312 LOG(GNUNET_ERROR_TYPE_DEBUG,
1313 "Adding shutdown task %p\n",
1321 * Schedule a new task to be run as soon as possible with the
1322 * (transitive) ignore-shutdown flag either explicitly set or
1323 * explicitly enabled. This task (and all tasks created from it,
1324 * other than by another call to this function) will either count or
1325 * not count for the "lifeness" of the process. This API is only
1326 * useful in a few special cases.
1328 * @param lifeness #GNUNET_YES if the task counts for lifeness, #GNUNET_NO if not.
1329 * @param task main function of the task
1330 * @param task_cls closure of @a task
1331 * @return unique task identifier for the job
1332 * only valid until @a task is started!
1334 struct GNUNET_SCHEDULER_Task *
1335 GNUNET_SCHEDULER_add_now_with_lifeness(int lifeness,
1336 GNUNET_SCHEDULER_TaskCallback task,
1339 struct GNUNET_SCHEDULER_Task *ret;
1341 ret = GNUNET_SCHEDULER_add_now(task, task_cls);
1342 ret->lifeness = lifeness;
1349 * check a raw file descriptor and abort if it is bad (for debugging purposes)
1351 * @param t the task related to the file descriptor
1352 * @param raw_fd the raw file descriptor to check
1355 check_fd(struct GNUNET_SCHEDULER_Task *t, int raw_fd)
1359 int flags = fcntl(raw_fd, F_GETFD);
1361 if ((flags == -1) && (errno == EBADF))
1363 LOG(GNUNET_ERROR_TYPE_ERROR,
1364 "Got invalid file descriptor %d!\n",
1375 * Schedule a new task to be run with a specified delay or when any of
1376 * the specified file descriptor sets is ready. The delay can be used
1377 * as a timeout on the socket(s) being ready. The task will be
1378 * scheduled for execution once either the delay has expired or any of
1379 * the socket operations is ready. This is the most general
1380 * function of the "add" family. Note that the "prerequisite_task"
1381 * must be satisfied in addition to any of the other conditions. In
1382 * other words, the task will be started when
1384 * (prerequisite-run)
1390 * @param delay how long should we wait?
1391 * @param priority priority to use
1392 * @param rfd file descriptor we want to read (can be -1)
1393 * @param wfd file descriptors we want to write (can be -1)
1394 * @param task main function of the task
1395 * @param task_cls closure of @a task
1396 * @return unique task identifier for the job
1397 * only valid until @a task is started!
1400 static struct GNUNET_SCHEDULER_Task *
1401 add_without_sets(struct GNUNET_TIME_Relative delay,
1402 enum GNUNET_SCHEDULER_Priority priority,
1403 const struct GNUNET_NETWORK_Handle *read_nh,
1404 const struct GNUNET_NETWORK_Handle *write_nh,
1405 const struct GNUNET_DISK_FileHandle *read_fh,
1406 const struct GNUNET_DISK_FileHandle *write_fh,
1407 GNUNET_SCHEDULER_TaskCallback task,
1410 struct GNUNET_SCHEDULER_Task *t;
1412 /* scheduler must be running */
1413 GNUNET_assert(NULL != scheduler_driver);
1414 GNUNET_assert(NULL != task);
1415 t = GNUNET_new(struct GNUNET_SCHEDULER_Task);
1416 GNUNET_async_scope_get(&t->scope);
1427 t->callback_cls = task_cls;
1429 check_fd(t, NULL != read_nh ? GNUNET_NETWORK_get_fd(read_nh) : -1);
1430 check_fd(t, NULL != write_nh ? GNUNET_NETWORK_get_fd(write_nh) : -1);
1431 check_fd(t, NULL != read_fh ? read_fh->fd : -1);
1432 check_fd(t, NULL != write_fh ? write_fh->fd : -1);
1435 t->start_time = GNUNET_TIME_absolute_get();
1437 t->timeout = GNUNET_TIME_relative_to_absolute(delay);
1438 t->priority = check_priority((priority == GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority : priority);
1439 t->lifeness = current_lifeness;
1440 GNUNET_CONTAINER_DLL_insert(pending_head,
1443 driver_add_multiple(t);
1444 max_priority_added = GNUNET_MAX(max_priority_added,
1453 * Schedule a new task to be run with a specified delay or when the
1454 * specified file descriptor is ready for reading. The delay can be
1455 * used as a timeout on the socket being ready. The task will be
1456 * scheduled for execution once either the delay has expired or the
1457 * socket operation is ready. It will be run with the DEFAULT priority.
1458 * Only allowed to be called as long as the scheduler is running, that
1459 * is one of the following conditions is met:
1461 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1462 * - #GNUNET_SCHEDULER_driver_init has been run and
1463 * #GNUNET_SCHEDULER_driver_done has not been called yet
1465 * @param delay when should this operation time out?
1466 * @param rfd read file-descriptor
1467 * @param task main function of the task
1468 * @param task_cls closure of @a task
1469 * @return unique task identifier for the job
1470 * only valid until @a task is started!
1472 struct GNUNET_SCHEDULER_Task *
1473 GNUNET_SCHEDULER_add_read_net(struct GNUNET_TIME_Relative delay,
1474 struct GNUNET_NETWORK_Handle *rfd,
1475 GNUNET_SCHEDULER_TaskCallback task,
1478 return GNUNET_SCHEDULER_add_read_net_with_priority(delay,
1479 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1480 rfd, task, task_cls);
1485 * Schedule a new task to be run with a specified priority and to be
1486 * run after the specified delay or when the specified file descriptor
1487 * is ready for reading. The delay can be used as a timeout on the
1488 * socket being ready. The task will be scheduled for execution once
1489 * either the delay has expired or the socket operation is ready. It
1490 * will be run with the DEFAULT priority.
1491 * Only allowed to be called as long as the scheduler is running, that
1492 * is one of the following conditions is met:
1494 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1495 * - #GNUNET_SCHEDULER_driver_init has been run and
1496 * #GNUNET_SCHEDULER_driver_done has not been called yet
1498 * @param delay when should this operation time out?
1499 * @param priority priority to use for the task
1500 * @param rfd read file-descriptor
1501 * @param task main function of the task
1502 * @param task_cls closure of @a task
1503 * @return unique task identifier for the job
1504 * only valid until @a task is started!
1506 struct GNUNET_SCHEDULER_Task *
1507 GNUNET_SCHEDULER_add_read_net_with_priority(struct GNUNET_TIME_Relative delay,
1508 enum GNUNET_SCHEDULER_Priority priority,
1509 struct GNUNET_NETWORK_Handle *rfd,
1510 GNUNET_SCHEDULER_TaskCallback task,
1513 return GNUNET_SCHEDULER_add_net_with_priority(delay, priority,
1522 * Schedule a new task to be run with a specified delay or when the
1523 * specified file descriptor is ready for writing. The delay can be
1524 * used as a timeout on the socket being ready. The task will be
1525 * scheduled for execution once either the delay has expired or the
1526 * socket operation is ready. It will be run with the priority of
1528 * Only allowed to be called as long as the scheduler is running, that
1529 * is one of the following conditions is met:
1531 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1532 * - #GNUNET_SCHEDULER_driver_init has been run and
1533 * #GNUNET_SCHEDULER_driver_done has not been called yet
1535 * @param delay when should this operation time out?
1536 * @param wfd write file-descriptor
1537 * @param task main function of the task
1538 * @param task_cls closure of @a task
1539 * @return unique task identifier for the job
1540 * only valid until @a task is started!
1542 struct GNUNET_SCHEDULER_Task *
1543 GNUNET_SCHEDULER_add_write_net(struct GNUNET_TIME_Relative delay,
1544 struct GNUNET_NETWORK_Handle *wfd,
1545 GNUNET_SCHEDULER_TaskCallback task,
1548 return GNUNET_SCHEDULER_add_net_with_priority(delay,
1549 GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1551 GNUNET_NO, GNUNET_YES,
1556 * Schedule a new task to be run with a specified delay or when the
1557 * specified file descriptor is ready. The delay can be
1558 * used as a timeout on the socket being ready. The task will be
1559 * scheduled for execution once either the delay has expired or the
1560 * socket operation is ready.
1561 * Only allowed to be called as long as the scheduler is running, that
1562 * is one of the following conditions is met:
1564 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1565 * - #GNUNET_SCHEDULER_driver_init has been run and
1566 * #GNUNET_SCHEDULER_driver_done has not been called yet
1568 * @param delay when should this operation time out?
1569 * @param priority priority of the task
1570 * @param fd file-descriptor
1571 * @param on_read whether to poll the file-descriptor for readability
1572 * @param on_write whether to poll the file-descriptor for writability
1573 * @param task main function of the task
1574 * @param task_cls closure of task
1575 * @return unique task identifier for the job
1576 * only valid until "task" is started!
1578 struct GNUNET_SCHEDULER_Task *
1579 GNUNET_SCHEDULER_add_net_with_priority(struct GNUNET_TIME_Relative delay,
1580 enum GNUNET_SCHEDULER_Priority priority,
1581 struct GNUNET_NETWORK_Handle *fd,
1584 GNUNET_SCHEDULER_TaskCallback task,
1587 /* scheduler must be running */
1588 GNUNET_assert(NULL != scheduler_driver);
1591 struct GNUNET_NETWORK_FDSet *s;
1592 struct GNUNET_SCHEDULER_Task * ret;
1594 GNUNET_assert(NULL != fd);
1595 s = GNUNET_NETWORK_fdset_create();
1596 GNUNET_NETWORK_fdset_set(s, fd);
1597 ret = GNUNET_SCHEDULER_add_select(
1600 on_write ? s : NULL,
1602 GNUNET_NETWORK_fdset_destroy(s);
1605 GNUNET_assert(on_read || on_write);
1606 GNUNET_assert(GNUNET_NETWORK_get_fd(fd) >= 0);
1607 return add_without_sets(delay, priority,
1608 on_read ? fd : NULL,
1609 on_write ? fd : NULL,
1618 * Schedule a new task to be run with a specified delay or when the
1619 * specified file descriptor is ready for reading. The delay can be
1620 * used as a timeout on the socket being ready. The task will be
1621 * scheduled for execution once either the delay has expired or the
1622 * socket operation is ready. It will be run with the DEFAULT priority.
1623 * Only allowed to be called as long as the scheduler is running, that
1624 * is one of the following conditions is met:
1626 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1627 * - #GNUNET_SCHEDULER_driver_init has been run and
1628 * #GNUNET_SCHEDULER_driver_done has not been called yet
1630 * @param delay when should this operation time out?
1631 * @param rfd read file-descriptor
1632 * @param task main function of the task
1633 * @param task_cls closure of @a task
1634 * @return unique task identifier for the job
1635 * only valid until @a task is started!
1637 struct GNUNET_SCHEDULER_Task *
1638 GNUNET_SCHEDULER_add_read_file(struct GNUNET_TIME_Relative delay,
1639 const struct GNUNET_DISK_FileHandle *rfd,
1640 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1642 return GNUNET_SCHEDULER_add_file_with_priority(
1643 delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1644 rfd, GNUNET_YES, GNUNET_NO,
1650 * Schedule a new task to be run with a specified delay or when the
1651 * specified file descriptor is ready for writing. The delay can be
1652 * used as a timeout on the socket being ready. The task will be
1653 * scheduled for execution once either the delay has expired or the
1654 * socket operation is ready. It will be run with the DEFAULT priority.
1655 * Only allowed to be called as long as the scheduler is running, that
1656 * is one of the following conditions is met:
1658 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1659 * - #GNUNET_SCHEDULER_driver_init has been run and
1660 * #GNUNET_SCHEDULER_driver_done has not been called yet
1662 * @param delay when should this operation time out?
1663 * @param wfd write file-descriptor
1664 * @param task main function of the task
1665 * @param task_cls closure of @a task
1666 * @return unique task identifier for the job
1667 * only valid until @a task is started!
1669 struct GNUNET_SCHEDULER_Task *
1670 GNUNET_SCHEDULER_add_write_file(struct GNUNET_TIME_Relative delay,
1671 const struct GNUNET_DISK_FileHandle *wfd,
1672 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1674 return GNUNET_SCHEDULER_add_file_with_priority(
1675 delay, GNUNET_SCHEDULER_PRIORITY_DEFAULT,
1676 wfd, GNUNET_NO, GNUNET_YES,
1682 * Schedule a new task to be run with a specified delay or when the
1683 * specified file descriptor is ready. The delay can be
1684 * used as a timeout on the socket being ready. The task will be
1685 * scheduled for execution once either the delay has expired or the
1686 * socket operation is ready.
1687 * Only allowed to be called as long as the scheduler is running, that
1688 * is one of the following conditions is met:
1690 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1691 * - #GNUNET_SCHEDULER_driver_init has been run and
1692 * #GNUNET_SCHEDULER_driver_done has not been called yet
1694 * @param delay when should this operation time out?
1695 * @param priority priority of the task
1696 * @param fd file-descriptor
1697 * @param on_read whether to poll the file-descriptor for readability
1698 * @param on_write whether to poll the file-descriptor for writability
1699 * @param task main function of the task
1700 * @param task_cls closure of @a task
1701 * @return unique task identifier for the job
1702 * only valid until @a task is started!
1704 struct GNUNET_SCHEDULER_Task *
1705 GNUNET_SCHEDULER_add_file_with_priority(struct GNUNET_TIME_Relative delay,
1706 enum GNUNET_SCHEDULER_Priority priority,
1707 const struct GNUNET_DISK_FileHandle *fd,
1708 int on_read, int on_write,
1709 GNUNET_SCHEDULER_TaskCallback task, void *task_cls)
1711 /* scheduler must be running */
1712 GNUNET_assert(NULL != scheduler_driver);
1715 struct GNUNET_NETWORK_FDSet *s;
1716 struct GNUNET_SCHEDULER_Task * ret;
1718 GNUNET_assert(NULL != fd);
1719 s = GNUNET_NETWORK_fdset_create();
1720 GNUNET_NETWORK_fdset_handle_set(s, fd);
1721 ret = GNUNET_SCHEDULER_add_select(
1724 on_write ? s : NULL,
1726 GNUNET_NETWORK_fdset_destroy(s);
1729 GNUNET_assert(on_read || on_write);
1730 GNUNET_assert(fd->fd >= 0);
1731 return add_without_sets(delay, priority,
1734 on_read ? fd : NULL,
1735 on_write ? fd : NULL,
1742 extract_handles(const struct GNUNET_NETWORK_FDSet *fdset,
1743 const struct GNUNET_NETWORK_Handle ***ntarget,
1744 unsigned int *extracted_nhandles,
1745 const struct GNUNET_DISK_FileHandle ***ftarget,
1746 unsigned int *extracted_fhandles)
1748 // FIXME: this implementation only works for unix, for WIN32 the file handles
1749 // in fdset must be handled separately
1750 const struct GNUNET_NETWORK_Handle **nhandles;
1751 const struct GNUNET_DISK_FileHandle **fhandles;
1752 unsigned int nhandles_len;
1753 unsigned int fhandles_len;
1759 for (int sock = 0; sock != fdset->nsds; ++sock)
1761 if (GNUNET_YES == GNUNET_NETWORK_fdset_test_native(fdset, sock))
1763 struct GNUNET_NETWORK_Handle *nhandle;
1764 struct GNUNET_DISK_FileHandle *fhandle;
1766 nhandle = GNUNET_NETWORK_socket_box_native(sock);
1767 if (NULL != nhandle)
1769 GNUNET_array_append(nhandles, nhandles_len, nhandle);
1773 fhandle = GNUNET_DISK_get_handle_from_int_fd(sock);
1774 if (NULL != fhandle)
1776 GNUNET_array_append(fhandles, fhandles_len, fhandle);
1785 *ntarget = nhandles_len > 0 ? nhandles : NULL;
1786 *ftarget = fhandles_len > 0 ? fhandles : NULL;
1787 *extracted_nhandles = nhandles_len;
1788 *extracted_fhandles = fhandles_len;
1793 * Schedule a new task to be run with a specified delay or when any of
1794 * the specified file descriptor sets is ready. The delay can be used
1795 * as a timeout on the socket(s) being ready. The task will be
1796 * scheduled for execution once either the delay has expired or any of
1797 * the socket operations is ready. This is the most general
1798 * function of the "add" family. Note that the "prerequisite_task"
1799 * must be satisfied in addition to any of the other conditions. In
1800 * other words, the task will be started when
1802 * (prerequisite-run)
1805 * || any-ws-ready) )
1807 * Only allowed to be called as long as the scheduler is running, that
1808 * is one of the following conditions is met:
1810 * - #GNUNET_SCHEDULER_run has been called and has not returned yet
1811 * - #GNUNET_SCHEDULER_driver_init has been run and
1812 * #GNUNET_SCHEDULER_driver_done has not been called yet
1814 * @param prio how important is this task?
1815 * @param delay how long should we wait?
1816 * @param rs set of file descriptors we want to read (can be NULL)
1817 * @param ws set of file descriptors we want to write (can be NULL)
1818 * @param task main function of the task
1819 * @param task_cls closure of @a task
1820 * @return unique task identifier for the job
1821 * only valid until @a task is started!
1823 struct GNUNET_SCHEDULER_Task *
1824 GNUNET_SCHEDULER_add_select(enum GNUNET_SCHEDULER_Priority prio,
1825 struct GNUNET_TIME_Relative delay,
1826 const struct GNUNET_NETWORK_FDSet *rs,
1827 const struct GNUNET_NETWORK_FDSet *ws,
1828 GNUNET_SCHEDULER_TaskCallback task,
1831 struct GNUNET_SCHEDULER_Task *t;
1832 const struct GNUNET_NETWORK_Handle **read_nhandles = NULL;
1833 const struct GNUNET_NETWORK_Handle **write_nhandles = NULL;
1834 const struct GNUNET_DISK_FileHandle **read_fhandles = NULL;
1835 const struct GNUNET_DISK_FileHandle **write_fhandles = NULL;
1836 unsigned int read_nhandles_len = 0;
1837 unsigned int write_nhandles_len = 0;
1838 unsigned int read_fhandles_len = 0;
1839 unsigned int write_fhandles_len = 0;
1841 /* scheduler must be running */
1842 GNUNET_assert(NULL != scheduler_driver);
1843 GNUNET_assert(NULL != task);
1844 int no_rs = (NULL == rs);
1845 int no_ws = (NULL == ws);
1846 int empty_rs = (NULL != rs) && (0 == rs->nsds);
1847 int empty_ws = (NULL != ws) && (0 == ws->nsds);
1848 int no_fds = (no_rs && no_ws) ||
1849 (empty_rs && empty_ws) ||
1850 (no_rs && empty_ws) ||
1851 (no_ws && empty_rs);
1860 &read_fhandles_len);
1866 &write_nhandles_len,
1868 &write_fhandles_len);
1872 * here we consider the case that a GNUNET_NETWORK_FDSet might be empty
1873 * although its maximum FD number (nsds) is greater than 0. We handle
1874 * this case gracefully because some libraries such as libmicrohttpd
1875 * only provide a hint what the maximum FD number in an FD set might be
1876 * and not the exact FD number (see e.g. gnunet-rest-service.c)
1878 int no_fds_extracted = (0 == read_nhandles_len) &&
1879 (0 == read_fhandles_len) &&
1880 (0 == write_nhandles_len) &&
1881 (0 == write_fhandles_len);
1882 if (no_fds || no_fds_extracted)
1883 return GNUNET_SCHEDULER_add_delayed_with_priority(delay,
1887 t = GNUNET_new(struct GNUNET_SCHEDULER_Task);
1888 GNUNET_async_scope_get(&t->scope);
1897 write_fhandles_len);
1899 t->callback_cls = task_cls;
1900 t->own_handles = GNUNET_YES;
1901 /* free the arrays of pointers to network / file handles, the actual
1902 * handles will be freed in destroy_task */
1903 GNUNET_array_grow(read_nhandles, read_nhandles_len, 0);
1904 GNUNET_array_grow(write_nhandles, write_nhandles_len, 0);
1905 GNUNET_array_grow(read_fhandles, read_fhandles_len, 0);
1906 GNUNET_array_grow(write_fhandles, write_fhandles_len, 0);
1908 t->start_time = GNUNET_TIME_absolute_get();
1910 t->timeout = GNUNET_TIME_relative_to_absolute(delay);
1912 check_priority((prio ==
1913 GNUNET_SCHEDULER_PRIORITY_KEEP) ? current_priority :
1915 t->lifeness = current_lifeness;
1916 GNUNET_CONTAINER_DLL_insert(pending_head,
1919 driver_add_multiple(t);
1920 max_priority_added = GNUNET_MAX(max_priority_added,
1922 LOG(GNUNET_ERROR_TYPE_DEBUG,
1931 * Function used by event-loop implementations to signal the scheduler
1932 * that a particular @a task is ready due to an event specified in the
1933 * et field of @a fdi.
1935 * This function will then queue the task to notify the application
1936 * that the task is ready (with the respective priority).
1938 * @param task the task that is ready
1939 * @param fdi information about the related FD
1942 GNUNET_SCHEDULER_task_ready(struct GNUNET_SCHEDULER_Task *task,
1943 struct GNUNET_SCHEDULER_FdInfo *fdi)
1945 enum GNUNET_SCHEDULER_Reason reason;
1947 reason = task->reason;
1948 if ((0 == (reason & GNUNET_SCHEDULER_REASON_READ_READY)) &&
1949 (0 != (GNUNET_SCHEDULER_ET_IN & fdi->et)))
1950 reason |= GNUNET_SCHEDULER_REASON_READ_READY;
1951 if ((0 == (reason & GNUNET_SCHEDULER_REASON_WRITE_READY)) &&
1952 (0 != (GNUNET_SCHEDULER_ET_OUT & fdi->et)))
1953 reason |= GNUNET_SCHEDULER_REASON_WRITE_READY;
1954 reason |= GNUNET_SCHEDULER_REASON_PREREQ_DONE;
1955 task->reason = reason;
1956 if (GNUNET_NO == task->in_ready_list)
1958 GNUNET_CONTAINER_DLL_remove(pending_head,
1961 queue_ready_task(task);
1967 * Function called by external event loop implementations to tell the
1968 * scheduler to run some of the tasks that are ready. Must be called
1969 * only after #GNUNET_SCHEDULER_driver_init has been called and before
1970 * #GNUNET_SCHEDULER_driver_done is called.
1971 * This function may return even though there are tasks left to run
1972 * just to give other tasks a chance as well. If we return #GNUNET_YES,
1973 * the event loop implementation should call this function again as
1974 * soon as possible, while if we return #GNUNET_NO it must block until
1975 * either the operating system has more work (the scheduler has no more
1976 * work to do right now) or the timeout set by the scheduler (using the
1977 * set_wakeup callback) is reached.
1979 * @param sh scheduler handle that was returned by
1980 * #GNUNET_SCHEDULER_driver_init
1981 * @return #GNUNET_YES if there are more tasks that are ready,
1982 * and thus we would like to run more (yield to avoid
1983 * blocking other activities for too long) #GNUNET_NO
1984 * if we are done running tasks (yield to block)
1987 GNUNET_SCHEDULER_do_work(struct GNUNET_SCHEDULER_Handle *sh)
1989 enum GNUNET_SCHEDULER_Priority p;
1990 struct GNUNET_SCHEDULER_Task *pos;
1991 struct GNUNET_TIME_Absolute now;
1993 /* check for tasks that reached the timeout! */
1994 now = GNUNET_TIME_absolute_get();
1995 pos = pending_timeout_head;
1998 struct GNUNET_SCHEDULER_Task *next = pos->next;
1999 if (now.abs_value_us >= pos->timeout.abs_value_us)
2000 pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
2001 if (0 == pos->reason)
2003 GNUNET_CONTAINER_DLL_remove(pending_timeout_head,
2004 pending_timeout_tail,
2006 if (pending_timeout_last == pos)
2007 pending_timeout_last = NULL;
2008 queue_ready_task(pos);
2014 struct GNUNET_SCHEDULER_Task *next = pos->next;
2015 if (now.abs_value_us >= pos->timeout.abs_value_us)
2017 pos->reason |= GNUNET_SCHEDULER_REASON_TIMEOUT;
2018 GNUNET_CONTAINER_DLL_remove(pending_head,
2021 queue_ready_task(pos);
2026 if (0 == ready_count)
2028 struct GNUNET_TIME_Absolute timeout = get_timeout();
2030 if (timeout.abs_value_us > now.abs_value_us)
2033 * The event loop called this function before the current timeout was
2034 * reached (and no FD tasks are ready). This is acceptable if
2036 * - the system time was changed while the driver was waiting for
2038 * - an external event loop called GNUnet API functions outside of
2039 * the callbacks called in GNUNET_SCHEDULER_do_work and thus
2040 * wasn't notified about the new timeout
2042 * It might also mean we are busy-waiting because of a programming
2043 * error in the external event loop.
2045 LOG(GNUNET_ERROR_TYPE_DEBUG,
2046 "GNUNET_SCHEDULER_do_work did not find any ready "
2047 "tasks and timeout has not been reached yet.\n");
2052 * the current timeout was reached but no ready tasks were found,
2053 * internal scheduler error!
2060 /* find out which task priority level we are going to
2061 process this time */
2062 max_priority_added = GNUNET_SCHEDULER_PRIORITY_KEEP;
2063 GNUNET_assert(NULL == ready_head[GNUNET_SCHEDULER_PRIORITY_KEEP]);
2064 /* yes, p>0 is correct, 0 is "KEEP" which should
2065 * always be an empty queue (see assertion)! */
2066 for (p = GNUNET_SCHEDULER_PRIORITY_COUNT - 1; p > 0; p--)
2068 pos = ready_head[p];
2072 GNUNET_assert(NULL != pos); /* ready_count wrong? */
2074 /* process all tasks at this priority level, then yield */
2075 while (NULL != (pos = ready_head[p]))
2077 GNUNET_CONTAINER_DLL_remove(ready_head[p],
2081 current_priority = pos->priority;
2082 current_lifeness = pos->lifeness;
2085 if (GNUNET_TIME_absolute_get_duration(pos->start_time).rel_value_us >
2086 DELAY_THRESHOLD.rel_value_us)
2088 LOG(GNUNET_ERROR_TYPE_DEBUG,
2089 "Task %p took %s to be scheduled\n",
2091 GNUNET_STRINGS_relative_time_to_string(GNUNET_TIME_absolute_get_duration(pos->start_time),
2095 tc.reason = pos->reason;
2096 GNUNET_NETWORK_fdset_zero(sh->rs);
2097 GNUNET_NETWORK_fdset_zero(sh->ws);
2098 // FIXME: do we have to remove FdInfos from fds if they are not ready?
2099 tc.fds_len = pos->fds_len;
2101 for (unsigned int i = 0; i != pos->fds_len; ++i)
2103 struct GNUNET_SCHEDULER_FdInfo *fdi = &pos->fds[i];
2104 if (0 != (GNUNET_SCHEDULER_ET_IN & fdi->et))
2106 GNUNET_NETWORK_fdset_set_native(sh->rs,
2109 if (0 != (GNUNET_SCHEDULER_ET_OUT & fdi->et))
2111 GNUNET_NETWORK_fdset_set_native(sh->ws,
2115 tc.read_ready = sh->rs;
2116 tc.write_ready = sh->ws;
2117 LOG(GNUNET_ERROR_TYPE_DEBUG,
2118 "Running task %p\n",
2120 GNUNET_assert(NULL != pos->callback);
2122 struct GNUNET_AsyncScopeSave old_scope;
2123 if (pos->scope.have_scope)
2124 GNUNET_async_scope_enter(&pos->scope.scope_id, &old_scope);
2126 GNUNET_async_scope_get(&old_scope);
2127 pos->callback(pos->callback_cls);
2128 GNUNET_async_scope_restore(&old_scope);
2130 if (NULL != pos->fds)
2132 int del_result = scheduler_driver->del(scheduler_driver->cls, pos);
2133 if (GNUNET_OK != del_result)
2135 LOG(GNUNET_ERROR_TYPE_ERROR,
2136 "driver could not delete task %p\n", pos);
2141 dump_backtrace(pos);
2145 shutdown_if_no_lifeness();
2146 if (0 == ready_count)
2148 scheduler_driver->set_wakeup(scheduler_driver->cls,
2152 scheduler_driver->set_wakeup(scheduler_driver->cls,
2153 GNUNET_TIME_absolute_get());
2159 * Function called by external event loop implementations to initialize
2160 * the scheduler. An external implementation has to provide @a driver
2161 * which contains callbacks for the scheduler (see definition of struct
2162 * #GNUNET_SCHEDULER_Driver). The callbacks are used to instruct the
2163 * external implementation to watch for events. If it detects any of
2164 * those events it is expected to call #GNUNET_SCHEDULER_do_work to let
2165 * the scheduler handle it. If an event is related to a specific task
2166 * (e.g. the scheduler gave instructions to watch a file descriptor),
2167 * the external implementation is expected to mark that task ready
2168 * before by calling #GNUNET_SCHEDULER_task_ready.
2170 * This function has to be called before any tasks are scheduled and
2171 * before GNUNET_SCHEDULER_do_work is called for the first time. It
2172 * allocates resources that have to be freed again by calling
2173 * #GNUNET_SCHEDULER_driver_done.
2175 * This function installs the same signal handlers as
2176 * #GNUNET_SCHEDULER_run. This means SIGTERM (and other similar signals)
2177 * will induce a call to #GNUNET_SCHEDULER_shutdown during the next
2178 * call to #GNUNET_SCHEDULER_do_work. As a result, SIGTERM causes all
2179 * active tasks to be scheduled with reason
2180 * #GNUNET_SCHEDULER_REASON_SHUTDOWN. (However, tasks added afterwards
2181 * will execute normally!). Note that any particular signal will only
2182 * shut down one scheduler; applications should always only create a
2185 * @param driver to use for the event loop
2186 * @return handle to be passed to #GNUNET_SCHEDULER_do_work and
2187 * #GNUNET_SCHEDULER_driver_done
2189 struct GNUNET_SCHEDULER_Handle *
2190 GNUNET_SCHEDULER_driver_init(const struct GNUNET_SCHEDULER_Driver *driver)
2192 struct GNUNET_SCHEDULER_Handle *sh;
2193 const struct GNUNET_DISK_FileHandle *pr;
2195 /* scheduler must not be running */
2196 GNUNET_assert(NULL == scheduler_driver);
2197 GNUNET_assert(NULL == shutdown_pipe_handle);
2198 /* general set-up */
2199 sh = GNUNET_new(struct GNUNET_SCHEDULER_Handle);
2200 shutdown_pipe_handle = GNUNET_DISK_pipe(GNUNET_NO,
2204 GNUNET_assert(NULL != shutdown_pipe_handle);
2205 pr = GNUNET_DISK_pipe_handle(shutdown_pipe_handle,
2206 GNUNET_DISK_PIPE_END_READ);
2208 scheduler_driver = driver;
2210 /* install signal handlers */
2211 LOG(GNUNET_ERROR_TYPE_DEBUG,
2212 "Registering signal handlers\n");
2213 sh->shc_int = GNUNET_SIGNAL_handler_install(SIGINT,
2214 &sighandler_shutdown);
2215 sh->shc_term = GNUNET_SIGNAL_handler_install(SIGTERM,
2216 &sighandler_shutdown);
2217 #if (SIGTERM != GNUNET_TERM_SIG)
2218 sh->shc_gterm = GNUNET_SIGNAL_handler_install(GNUNET_TERM_SIG,
2219 &sighandler_shutdown);
2222 sh->shc_pipe = GNUNET_SIGNAL_handler_install(SIGPIPE,
2224 sh->shc_quit = GNUNET_SIGNAL_handler_install(SIGQUIT,
2225 &sighandler_shutdown);
2226 sh->shc_hup = GNUNET_SIGNAL_handler_install(SIGHUP,
2227 &sighandler_shutdown);
2230 /* Setup initial tasks */
2231 current_priority = GNUNET_SCHEDULER_PRIORITY_DEFAULT;
2232 current_lifeness = GNUNET_NO;
2233 install_parent_control_task =
2234 GNUNET_SCHEDULER_add_now(&install_parent_control_handler,
2236 shutdown_pipe_task =
2237 GNUNET_SCHEDULER_add_read_file(GNUNET_TIME_UNIT_FOREVER_REL,
2241 current_lifeness = GNUNET_YES;
2242 scheduler_driver->set_wakeup(scheduler_driver->cls,
2244 /* begin main event loop */
2245 sh->rs = GNUNET_NETWORK_fdset_create();
2246 sh->ws = GNUNET_NETWORK_fdset_create();
2247 GNUNET_NETWORK_fdset_handle_set(sh->rs, pr);
2253 * Counter-part of #GNUNET_SCHEDULER_driver_init. Has to be called
2254 * by external event loop implementations after the scheduler has
2255 * shut down. This is the case if both of the following conditions
2258 * - all tasks the scheduler has added through the driver's add
2259 * callback have been removed again through the driver's del
2261 * - the timeout the scheduler has set through the driver's
2262 * add_wakeup callback is FOREVER
2264 * @param sh the handle returned by #GNUNET_SCHEDULER_driver_init
2267 GNUNET_SCHEDULER_driver_done(struct GNUNET_SCHEDULER_Handle *sh)
2269 GNUNET_assert(NULL == pending_head);
2270 GNUNET_assert(NULL == pending_timeout_head);
2271 GNUNET_assert(NULL == shutdown_head);
2272 for (int i = 0; i != GNUNET_SCHEDULER_PRIORITY_COUNT; ++i)
2274 GNUNET_assert(NULL == ready_head[i]);
2276 GNUNET_NETWORK_fdset_destroy(sh->rs);
2277 GNUNET_NETWORK_fdset_destroy(sh->ws);
2279 /* uninstall signal handlers */
2280 GNUNET_SIGNAL_handler_uninstall(sh->shc_int);
2281 GNUNET_SIGNAL_handler_uninstall(sh->shc_term);
2282 #if (SIGTERM != GNUNET_TERM_SIG)
2283 GNUNET_SIGNAL_handler_uninstall(sh->shc_gterm);
2286 GNUNET_SIGNAL_handler_uninstall(sh->shc_pipe);
2287 GNUNET_SIGNAL_handler_uninstall(sh->shc_quit);
2288 GNUNET_SIGNAL_handler_uninstall(sh->shc_hup);
2290 GNUNET_DISK_pipe_close(shutdown_pipe_handle);
2291 shutdown_pipe_handle = NULL;
2292 scheduler_driver = NULL;
2298 select_loop(struct GNUNET_SCHEDULER_Handle *sh,
2299 struct DriverContext *context)
2301 struct GNUNET_NETWORK_FDSet *rs;
2302 struct GNUNET_NETWORK_FDSet *ws;
2305 GNUNET_assert(NULL != context);
2306 rs = GNUNET_NETWORK_fdset_create();
2307 ws = GNUNET_NETWORK_fdset_create();
2308 while ((NULL != context->scheduled_head) ||
2309 (GNUNET_TIME_UNIT_FOREVER_ABS.abs_value_us != context->timeout.abs_value_us))
2311 LOG(GNUNET_ERROR_TYPE_DEBUG,
2312 "select timeout = %s\n",
2313 GNUNET_STRINGS_absolute_time_to_string(context->timeout));
2315 GNUNET_NETWORK_fdset_zero(rs);
2316 GNUNET_NETWORK_fdset_zero(ws);
2318 for (struct Scheduled *pos = context->scheduled_head;
2322 if (0 != (GNUNET_SCHEDULER_ET_IN & pos->et))
2324 GNUNET_NETWORK_fdset_set_native(rs, pos->fdi->sock);
2326 if (0 != (GNUNET_SCHEDULER_ET_OUT & pos->et))
2328 GNUNET_NETWORK_fdset_set_native(ws, pos->fdi->sock);
2331 struct GNUNET_TIME_Relative time_remaining =
2332 GNUNET_TIME_absolute_get_remaining(context->timeout);
2333 if (NULL == scheduler_select)
2335 select_result = GNUNET_NETWORK_socket_select(rs,
2342 select_result = scheduler_select(scheduler_select_cls,
2348 if (select_result == GNUNET_SYSERR)
2353 LOG_STRERROR(GNUNET_ERROR_TYPE_ERROR,
2365 if (0 != system(lsof))
2366 LOG_STRERROR(GNUNET_ERROR_TYPE_WARNING,
2371 for (struct Scheduled *s = context->scheduled_head;
2375 int flags = fcntl(s->fdi->sock,
2378 if ((flags == -1) &&
2381 LOG(GNUNET_ERROR_TYPE_ERROR,
2382 "Got invalid file descriptor %d!\n",
2385 dump_backtrace(s->task);
2391 GNUNET_NETWORK_fdset_destroy(rs);
2392 GNUNET_NETWORK_fdset_destroy(ws);
2393 return GNUNET_SYSERR;
2395 if (select_result > 0)
2397 for (struct Scheduled *pos = context->scheduled_head;
2401 int is_ready = GNUNET_NO;
2403 if (0 != (GNUNET_SCHEDULER_ET_IN & pos->et) &&
2405 GNUNET_NETWORK_fdset_test_native(rs,
2408 pos->fdi->et |= GNUNET_SCHEDULER_ET_IN;
2409 is_ready = GNUNET_YES;
2411 if (0 != (GNUNET_SCHEDULER_ET_OUT & pos->et) &&
2413 GNUNET_NETWORK_fdset_test_native(ws,
2416 pos->fdi->et |= GNUNET_SCHEDULER_ET_OUT;
2417 is_ready = GNUNET_YES;
2419 if (GNUNET_YES == is_ready)
2421 GNUNET_SCHEDULER_task_ready(pos->task,
2426 if (GNUNET_YES == GNUNET_SCHEDULER_do_work(sh))
2428 LOG(GNUNET_ERROR_TYPE_DEBUG,
2429 "scheduler has more tasks ready!\n");
2432 GNUNET_NETWORK_fdset_destroy(rs);
2433 GNUNET_NETWORK_fdset_destroy(ws);
2439 select_add(void *cls,
2440 struct GNUNET_SCHEDULER_Task *task,
2441 struct GNUNET_SCHEDULER_FdInfo *fdi)
2443 struct DriverContext *context = cls;
2445 GNUNET_assert(NULL != context);
2446 GNUNET_assert(NULL != task);
2447 GNUNET_assert(NULL != fdi);
2448 GNUNET_assert(0 != (GNUNET_SCHEDULER_ET_IN & fdi->et) ||
2449 0 != (GNUNET_SCHEDULER_ET_OUT & fdi->et));
2451 if (!((NULL != fdi->fd) ^ (NULL != fdi->fh)) || (fdi->sock < 0))
2453 /* exactly one out of {fd, hf} must be != NULL and the OS handle must be valid */
2454 return GNUNET_SYSERR;
2457 struct Scheduled *scheduled = GNUNET_new(struct Scheduled);
2458 scheduled->task = task;
2459 scheduled->fdi = fdi;
2460 scheduled->et = fdi->et;
2462 GNUNET_CONTAINER_DLL_insert(context->scheduled_head,
2463 context->scheduled_tail,
2470 select_del(void *cls,
2471 struct GNUNET_SCHEDULER_Task *task)
2473 struct DriverContext *context;
2474 struct Scheduled *pos;
2477 GNUNET_assert(NULL != cls);
2480 ret = GNUNET_SYSERR;
2481 pos = context->scheduled_head;
2484 struct Scheduled *next = pos->next;
2485 if (pos->task == task)
2487 GNUNET_CONTAINER_DLL_remove(context->scheduled_head,
2488 context->scheduled_tail,
2500 select_set_wakeup(void *cls,
2501 struct GNUNET_TIME_Absolute dt)
2503 struct DriverContext *context = cls;
2505 GNUNET_assert(NULL != context);
2506 context->timeout = dt;
2511 * Obtain the driver for using select() as the event loop.
2513 * @return NULL on error
2515 struct GNUNET_SCHEDULER_Driver *
2516 GNUNET_SCHEDULER_driver_select()
2518 struct GNUNET_SCHEDULER_Driver *select_driver;
2520 select_driver = GNUNET_new(struct GNUNET_SCHEDULER_Driver);
2522 select_driver->add = &select_add;
2523 select_driver->del = &select_del;
2524 select_driver->set_wakeup = &select_set_wakeup;
2526 return select_driver;
2531 * Change the async scope for the currently executing task and (transitively)
2532 * for all tasks scheduled by the current task after calling this function.
2533 * Nested tasks can begin their own nested async scope.
2535 * Once the current task is finished, the async scope ID is reset to
2536 * its previous value.
2538 * Must only be called from a running task.
2540 * @param aid the asynchronous scope id to enter
2543 GNUNET_SCHEDULER_begin_async_scope(struct GNUNET_AsyncScopeId *aid)
2545 struct GNUNET_AsyncScopeSave dummy_old_scope;
2547 GNUNET_assert(NULL != active_task);
2548 /* Since we're in a task, the context will be automatically
2549 restored by the scheduler. */
2550 GNUNET_async_scope_enter(aid, &dummy_old_scope);
2554 /* end of scheduler.c */