5 Author: Pekka Riikonen <priikone@silcnet.org>
7 Copyright (C) 1998 - 2002 Pekka Riikonen
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; version 2 of the License.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
21 #include "silcincludes.h"
22 #include "silcschedule_i.h"
24 /* Forward declarations */
25 typedef struct SilcTaskQueueStruct *SilcTaskQueue;
27 /* System specific routines. Implemented under unix/, win32/ and such. */
29 /* System specific select(). Returns same values as normal select(). */
30 int silc_select(SilcScheduleFd fds, SilcUInt32 fds_count,
31 struct timeval *timeout);
33 /* Initializes the platform specific scheduler. This for example initializes
34 the wakeup mechanism of the scheduler. In multi-threaded environment
35 the scheduler needs to be wakenup when tasks are added or removed from
36 the task queues. Returns context to the platform specific scheduler. */
37 void *silc_schedule_internal_init(SilcSchedule schedule, void *context);
39 /* Uninitializes the platform specific scheduler context. */
40 void silc_schedule_internal_uninit(void *context);
42 /* Wakes up the scheduler. This is platform specific routine */
43 void silc_schedule_internal_wakeup(void *context);
46 void silc_schedule_internal_signal_register(void *context,
48 SilcTaskCallback callback,
49 void *callback_context);
51 /* Unregister signal */
52 void silc_schedule_internal_signal_unregister(void *context,
54 SilcTaskCallback callback,
55 void *callback_context);
57 /* Mark signal to be called later. */
58 void silc_schedule_internal_signal_call(void *context, SilcUInt32 signal);
60 /* Call all signals */
61 void silc_schedule_internal_signals_call(void *context,
62 SilcSchedule schedule);
64 /* Block registered signals in scheduler. */
65 void silc_schedule_internal_signals_block(void *context);
67 /* Unblock registered signals in schedule. */
68 void silc_schedule_internal_signals_unblock(void *context);
70 /* Internal task management routines. */
72 static void silc_schedule_dispatch_timeout(SilcSchedule schedule,
74 static void silc_task_queue_alloc(SilcTaskQueue *queue);
75 static void silc_task_queue_free(SilcTaskQueue queue);
76 static SilcTask silc_task_find(SilcTaskQueue queue, SilcUInt32 fd);
77 static SilcTask silc_task_add(SilcTaskQueue queue, SilcTask newtask,
78 SilcTaskPriority priority);
79 static SilcTask silc_task_get_first(SilcTaskQueue queue, SilcTask first);
80 static SilcTask silc_task_add_timeout(SilcTaskQueue queue, SilcTask newtask,
81 SilcTaskPriority priority);
82 static int silc_schedule_task_remove(SilcTaskQueue queue, SilcTask task);
83 static void silc_task_del_by_context(SilcTaskQueue queue, void *context);
84 static void silc_task_del_by_callback(SilcTaskQueue queue,
85 SilcTaskCallback callback);
86 static void silc_task_del_by_fd(SilcTaskQueue queue, SilcUInt32 fd);
88 /* Returns the task queue by task type */
89 #define SILC_SCHEDULE_GET_QUEUE(type) \
90 (type == SILC_TASK_FD ? schedule->fd_queue : \
91 type == SILC_TASK_TIMEOUT ? schedule->timeout_queue : \
92 schedule->generic_queue)
94 /* Locks. These also blocks signals that we care about and thus guarantee
95 that while we are in scheduler no signals can happen. This way we can
96 synchronise signals with SILC Scheduler. */
97 #define SILC_SCHEDULE_LOCK(schedule) \
99 silc_schedule_internal_signals_block(schedule->internal); \
100 silc_mutex_lock(schedule->lock); \
102 #define SILC_SCHEDULE_UNLOCK(schedule) \
104 silc_mutex_unlock(schedule->lock); \
105 silc_schedule_internal_signals_unblock(schedule->internal); \
108 /* SILC Task object. Represents one task in the scheduler. */
109 struct SilcTaskStruct {
111 SilcTaskCallback callback; /* Task callback */
112 void *context; /* Task callback context */
113 struct timeval timeout; /* Set for timeout tasks */
114 unsigned int valid : 1; /* Set when task is valid */
115 unsigned int priority : 2; /* Priority of the task */
116 unsigned int type : 5; /* Type of the task */
118 /* Pointers forming doubly linked circular list */
119 struct SilcTaskStruct *next;
120 struct SilcTaskStruct *prev;
123 /* SILC Task Queue object. The queue holds all the tasks in the scheduler.
124 There are always three task queues in the scheduler. One for non-timeout
125 tasks (fd tasks performing tasks over specified file descriptor),
126 one for timeout tasks and one for generic tasks. */
127 struct SilcTaskQueueStruct {
128 SilcTask task; /* Pointer to all tasks */
129 struct timeval timeout; /* Current timeout */
130 SILC_MUTEX_DEFINE(lock); /* Queue's lock */
134 SILC Scheduler structure.
136 This is the actual schedule object in SILC. Both SILC client and server
137 uses this same scheduler. Actually, this scheduler could be used by any
138 program needing scheduling.
140 Following short description of the fields:
142 SilcTaskQueue fd_queue
144 Task queue hook for non-timeout tasks. Usually this means that these
145 tasks perform different kind of I/O on file descriptors. File
146 descriptors are usually network sockets but they actually can be
147 any file descriptors. This hook is initialized in silc_schedule_init
148 function. Timeout tasks should not be added to this queue because
149 they will never expire.
151 SilcTaskQueue timeout_queue
153 Task queue hook for timeout tasks. This hook is reserved specificly
154 for tasks with timeout. Non-timeout tasks should not be added to this
155 queue because they will never get scheduled. This hook is also
156 initialized in silc_schedule_init function.
158 SilcTaskQueue generic_queue
160 Task queue hook for generic tasks. This hook is reserved specificly
161 for generic tasks, tasks that apply to all file descriptors, except
162 to those that have specificly registered a non-timeout task. This hook
163 is also initialized in silc_schedule_init function.
165 SilcScheduleFd fd_list
167 List of file descriptors the scheduler is supposed to be listenning.
168 This is updated internally.
173 Size of the fd_list list. There can be `max_fd' many tasks in
174 the scheduler at once. The `last_fd' is the last valid entry
177 struct timeval *timeout;
179 Pointer to the schedules next timeout. Value of this timeout is
180 automatically updated in the silc_schedule function.
184 Marks validity of the scheduler. This is a boolean value. When this
185 is false the scheduler is terminated and the program will end. This
186 set to true when the scheduler is initialized with silc_schedule_init
192 File descriptor sets for select(). These are automatically managed
193 by the scheduler and should not be touched otherwise.
197 System specific scheduler context.
199 SILC_MUTEX_DEFINE(lock)
205 TRUE when tasks has been registered from signals. Next round in
206 scheduler will call the callbacks when this is TRUE.
209 struct SilcScheduleStruct {
210 void *app_context; /* Application specific context */
211 SilcTaskQueue fd_queue;
212 SilcTaskQueue timeout_queue;
213 SilcTaskQueue generic_queue;
214 SilcScheduleFd fd_list;
217 struct timeval *timeout;
220 SILC_MUTEX_DEFINE(lock);
225 /* Initializes the scheduler. This returns the scheduler context that
226 is given as arugment usually to all silc_schedule_* functions.
227 The `max_tasks' indicates the number of maximum tasks that the
228 scheduler can handle. The `app_context' is application specific
229 context that is delivered to task callbacks. */
231 SilcSchedule silc_schedule_init(int max_tasks, void *app_context)
233 SilcSchedule schedule;
235 SILC_LOG_DEBUG(("Initializing scheduler"));
237 schedule = silc_calloc(1, sizeof(*schedule));
239 /* Allocate three task queues, one for file descriptor based tasks,
240 one for timeout tasks and one for generic tasks. */
241 silc_task_queue_alloc(&schedule->fd_queue);
242 silc_task_queue_alloc(&schedule->timeout_queue);
243 silc_task_queue_alloc(&schedule->generic_queue);
248 /* Initialize the scheduler */
249 schedule->fd_list = silc_calloc(max_tasks, sizeof(*schedule->fd_list));
250 schedule->max_fd = max_tasks;
251 schedule->timeout = NULL;
252 schedule->valid = TRUE;
253 schedule->app_context = app_context;
255 /* Allocate scheduler lock */
256 silc_mutex_alloc(&schedule->lock);
258 /* Initialize the platform specific scheduler. */
259 schedule->internal = silc_schedule_internal_init(schedule, app_context);
264 /* Uninitializes the schedule. This is called when the program is ready
265 to end. This removes all tasks and task queues. Returns FALSE if the
266 scheduler could not be uninitialized. This happens when the scheduler
267 is still valid and silc_schedule_stop has not been called. */
269 bool silc_schedule_uninit(SilcSchedule schedule)
271 SILC_LOG_DEBUG(("Uninitializing scheduler"));
273 if (schedule->valid == TRUE)
276 /* Dispatch all timeouts before going away */
277 SILC_SCHEDULE_LOCK(schedule);
278 silc_mutex_lock(schedule->timeout_queue->lock);
279 silc_schedule_dispatch_timeout(schedule, TRUE);
280 silc_mutex_unlock(schedule->timeout_queue->lock);
281 SILC_SCHEDULE_UNLOCK(schedule);
283 /* Deliver signals before going away */
284 if (schedule->signal_tasks) {
285 silc_schedule_internal_signals_call(schedule->internal, schedule);
286 schedule->signal_tasks = FALSE;
289 /* Unregister all tasks */
290 silc_schedule_task_remove(schedule->fd_queue, SILC_ALL_TASKS);
291 silc_schedule_task_remove(schedule->timeout_queue, SILC_ALL_TASKS);
292 silc_schedule_task_remove(schedule->generic_queue, SILC_ALL_TASKS);
294 /* Unregister all task queues */
295 silc_task_queue_free(schedule->fd_queue);
296 silc_task_queue_free(schedule->timeout_queue);
297 silc_task_queue_free(schedule->generic_queue);
299 silc_free(schedule->fd_list);
301 /* Uninit the platform specific scheduler. */
302 silc_schedule_internal_uninit(schedule->internal);
304 silc_mutex_free(schedule->lock);
310 /* Enlarge the capabilities of the scheduler to handle tasks to `max_tasks'. */
312 bool silc_schedule_reinit(SilcSchedule schedule, int max_tasks)
314 SILC_SCHEDULE_LOCK(schedule);
315 if (schedule->max_fd <= max_tasks)
317 schedule->fd_list = silc_realloc(schedule->fd_list,
318 (sizeof(*schedule->fd_list) * max_tasks));
319 schedule->max_fd = max_tasks;
320 SILC_SCHEDULE_UNLOCK(schedule);
324 /* Stops the schedule even if it is not supposed to be stopped yet.
325 After calling this, one should call silc_schedule_uninit (after the
326 silc_schedule has returned). */
328 void silc_schedule_stop(SilcSchedule schedule)
330 SILC_LOG_DEBUG(("Stopping scheduler"));
331 SILC_SCHEDULE_LOCK(schedule);
332 schedule->valid = FALSE;
333 SILC_SCHEDULE_UNLOCK(schedule);
336 /* Executes nontimeout tasks. It then checks whether any of ther fd tasks
337 was signaled by the silc_select. If some task was not signaled then
338 all generic tasks are executed for that task. The generic tasks are
339 never executed for task that has explicit fd task set. */
340 /* This holds the schedule->lock and the queue locks. */
342 static void silc_schedule_dispatch_nontimeout(SilcSchedule schedule)
346 SilcUInt32 fd, last_fd = schedule->last_fd;
348 for (i = 0; i <= last_fd; i++) {
349 if (schedule->fd_list[i].events == 0)
352 fd = schedule->fd_list[i].fd;
354 /* First check whether this fd has task in the fd queue */
355 silc_mutex_lock(schedule->fd_queue->lock);
356 task = silc_task_find(schedule->fd_queue, fd);
358 /* If the task was found then execute its callbacks. If not then
359 execute all generic tasks for that fd. */
361 /* Validity of the task is checked always before and after
362 execution beacuse the task might have been unregistered
363 in the callback function, ie. it is not valid anymore. */
365 /* Is the task ready for reading */
366 if (task->valid && schedule->fd_list[i].revents & SILC_TASK_READ) {
367 silc_mutex_unlock(schedule->fd_queue->lock);
368 SILC_SCHEDULE_UNLOCK(schedule);
369 task->callback(schedule, schedule->app_context,
370 SILC_TASK_READ, task->fd, task->context);
371 SILC_SCHEDULE_LOCK(schedule);
372 silc_mutex_lock(schedule->fd_queue->lock);
375 /* Is the task ready for writing */
376 if (task->valid && schedule->fd_list[i].revents & SILC_TASK_WRITE) {
377 silc_mutex_unlock(schedule->fd_queue->lock);
378 SILC_SCHEDULE_UNLOCK(schedule);
379 task->callback(schedule, schedule->app_context,
380 SILC_TASK_WRITE, task->fd, task->context);
381 SILC_SCHEDULE_LOCK(schedule);
382 silc_mutex_lock(schedule->fd_queue->lock);
386 silc_schedule_task_remove(schedule->fd_queue, task);
388 silc_mutex_unlock(schedule->fd_queue->lock);
390 /* Run generic tasks for this fd. */
392 silc_mutex_unlock(schedule->fd_queue->lock);
394 silc_mutex_lock(schedule->generic_queue->lock);
395 if (!schedule->generic_queue->task) {
396 silc_mutex_unlock(schedule->generic_queue->lock);
400 task = schedule->generic_queue->task;
402 /* Validity of the task and fd is checked always before and after
403 execution beacuse the task might have been unregistered
404 in the callback function, ie. it is not valid anymore. */
406 /* Is the task ready for reading */
407 if (task->valid && schedule->fd_list[i].revents & SILC_TASK_READ &&
408 fd == schedule->fd_list[i].fd) {
409 silc_mutex_unlock(schedule->generic_queue->lock);
410 SILC_SCHEDULE_UNLOCK(schedule);
411 task->callback(schedule, schedule->app_context,
412 SILC_TASK_READ, fd, task->context);
413 SILC_SCHEDULE_LOCK(schedule);
414 silc_mutex_lock(schedule->generic_queue->lock);
417 /* Is the task ready for writing */
418 if (task->valid && schedule->fd_list[i].revents & SILC_TASK_WRITE &&
419 fd == schedule->fd_list[i].fd) {
420 silc_mutex_unlock(schedule->generic_queue->lock);
421 SILC_SCHEDULE_UNLOCK(schedule);
422 task->callback(schedule, schedule->app_context,
423 SILC_TASK_WRITE, fd, task->context);
424 SILC_SCHEDULE_LOCK(schedule);
425 silc_mutex_lock(schedule->generic_queue->lock);
429 /* Invalid (unregistered) tasks are removed from the
431 if (schedule->generic_queue->task == task->next) {
432 silc_schedule_task_remove(schedule->generic_queue, task);
433 silc_mutex_unlock(schedule->generic_queue->lock);
438 silc_schedule_task_remove(schedule->generic_queue, task);
442 /* Break if there isn't more tasks in the queue */
443 if (schedule->generic_queue->task == task->next)
449 silc_mutex_unlock(schedule->generic_queue->lock);
454 /* Executes all tasks whose timeout has expired. The task is removed from
455 the task queue after the callback function has returned. Also, invalid
456 tasks are removed here. We don't have to care about priorities because
457 tasks are already sorted in their priority order at the registration
459 /* This holds the schedule->lock and the schedule->timeout_queue->lock */
461 static void silc_schedule_dispatch_timeout(SilcSchedule schedule,
464 SilcTaskQueue queue = schedule->timeout_queue;
466 struct timeval curtime;
468 SILC_LOG_DEBUG(("Running timeout tasks"));
470 silc_gettimeofday(&curtime);
472 queue = schedule->timeout_queue;
473 if (queue && queue->task) {
476 /* Walk thorugh all tasks in the particular task queue and run all
477 the expired tasks. */
479 /* Execute the task if the timeout has expired */
481 silc_compare_timeval(&task->timeout, &curtime)) {
483 silc_mutex_unlock(queue->lock);
484 SILC_SCHEDULE_UNLOCK(schedule);
485 task->callback(schedule, schedule->app_context,
486 SILC_TASK_EXPIRE, task->fd, task->context);
487 SILC_SCHEDULE_LOCK(schedule);
488 silc_mutex_lock(queue->lock);
491 /* Break if there isn't more tasks in the queue */
492 if (queue->task == task->next) {
493 silc_schedule_task_remove(queue, task);
499 /* Remove the task from queue */
500 silc_schedule_task_remove(queue, task->prev);
502 /* The timeout hasn't expired, check for next one */
504 /* Break if there isn't more tasks in the queue */
505 if (queue->task == task->next)
514 /* Calculates next timeout for select(). This is the timeout value
515 when at earliest some of the timeout tasks expire. If this is in the
516 past, they will be run now. */
517 /* This holds the schedule->lock and the schedule->timeout_queue->lock */
519 static void silc_schedule_select_timeout(SilcSchedule schedule)
521 SilcTaskQueue queue = schedule->timeout_queue;
523 struct timeval curtime;
525 /* Get the current time */
526 silc_gettimeofday(&curtime);
527 schedule->timeout = NULL;
529 /* First task in the task queue has always the smallest timeout. */
532 if (task && task->valid == TRUE) {
533 /* If the timeout is in past, we will run the task and all other
534 timeout tasks from the past. */
535 if (silc_compare_timeval(&task->timeout, &curtime)) {
536 silc_schedule_dispatch_timeout(schedule, FALSE);
538 /* The task(s) has expired and doesn't exist on the task queue
539 anymore. We continue with new timeout. */
540 queue = schedule->timeout_queue;
542 if (task == NULL || task->valid == FALSE)
546 /* Calculate the next timeout for select() */
547 queue->timeout.tv_sec = task->timeout.tv_sec - curtime.tv_sec;
548 queue->timeout.tv_usec = task->timeout.tv_usec - curtime.tv_usec;
549 if (queue->timeout.tv_sec < 0)
550 queue->timeout.tv_sec = 0;
552 /* We wouldn't want to go under zero, check for it. */
553 if (queue->timeout.tv_usec < 0) {
554 queue->timeout.tv_sec -= 1;
555 if (queue->timeout.tv_sec < 0)
556 queue->timeout.tv_sec = 0;
557 queue->timeout.tv_usec += 1000000L;
560 /* We've got the timeout value */
563 /* Task is not valid, remove it and try next one. */
564 silc_schedule_task_remove(queue, task);
566 if (queue->task == NULL)
571 /* Save the timeout */
573 schedule->timeout = &queue->timeout;
574 SILC_LOG_DEBUG(("timeout: sec=%d, usec=%d", schedule->timeout->tv_sec,
575 schedule->timeout->tv_usec));
579 /* Runs the scheduler once and then returns. */
581 bool silc_schedule_one(SilcSchedule schedule, int timeout_usecs)
583 struct timeval timeout;
586 SILC_LOG_DEBUG(("In scheduler loop"));
588 if (!schedule->is_locked)
589 SILC_SCHEDULE_LOCK(schedule);
591 /* Deliver signals if any has been set to be called */
592 if (schedule->signal_tasks) {
593 SILC_SCHEDULE_UNLOCK(schedule);
594 silc_schedule_internal_signals_call(schedule->internal, schedule);
595 schedule->signal_tasks = FALSE;
596 SILC_SCHEDULE_LOCK(schedule);
599 /* If the task queues aren't initialized or we aren't valid anymore
601 if ((!schedule->fd_queue && !schedule->timeout_queue
602 && !schedule->generic_queue) || schedule->valid == FALSE) {
603 SILC_LOG_DEBUG(("Scheduler not valid anymore, exiting"));
604 if (!schedule->is_locked)
605 SILC_SCHEDULE_UNLOCK(schedule);
609 /* Calculate next timeout for silc_select(). This is the timeout value
610 when at earliest some of the timeout tasks expire. */
611 silc_mutex_lock(schedule->timeout_queue->lock);
612 silc_schedule_select_timeout(schedule);
613 silc_mutex_unlock(schedule->timeout_queue->lock);
615 if (timeout_usecs >= 0) {
617 timeout.tv_usec = timeout_usecs;
618 schedule->timeout = &timeout;
621 SILC_SCHEDULE_UNLOCK(schedule);
623 /* This is the main select(). The program blocks here until some
624 of the selected file descriptors change status or the selected
626 SILC_LOG_DEBUG(("Select"));
627 ret = silc_select(schedule->fd_list, schedule->last_fd + 1,
630 SILC_SCHEDULE_LOCK(schedule);
637 SILC_LOG_ERROR(("Error in select(): %s", strerror(errno)));
641 silc_mutex_lock(schedule->timeout_queue->lock);
642 silc_schedule_dispatch_timeout(schedule, FALSE);
643 silc_mutex_unlock(schedule->timeout_queue->lock);
646 /* There is some data available now */
647 SILC_LOG_DEBUG(("Running non-timeout tasks"));
648 silc_schedule_dispatch_nontimeout(schedule);
652 if (!schedule->is_locked)
653 SILC_SCHEDULE_UNLOCK(schedule);
658 /* The SILC scheduler. This is actually the main routine in SILC programs.
659 When this returns the program is to be ended. Before this function can
660 be called, one must call silc_schedule_init function. */
662 void silc_schedule(SilcSchedule schedule)
664 SILC_LOG_DEBUG(("Running scheduler"));
666 if (schedule->valid == FALSE) {
667 SILC_LOG_ERROR(("Scheduler is not valid, stopping"));
671 SILC_SCHEDULE_LOCK(schedule);
672 schedule->is_locked = TRUE;
674 /* Start the scheduler loop */
675 while (silc_schedule_one(schedule, -1))
678 SILC_SCHEDULE_UNLOCK(schedule);
681 /* Wakes up the scheduler. This is used only in multi-threaded
682 environments where threads may add new tasks or remove old tasks
683 from task queues. This is called to wake up the scheduler in the
684 main thread so that it detects the changes in the task queues.
685 If threads support is not compiled in this function has no effect.
686 Implementation of this function is platform specific. */
688 void silc_schedule_wakeup(SilcSchedule schedule)
691 SILC_LOG_DEBUG(("Wakeup scheduler"));
692 SILC_SCHEDULE_LOCK(schedule);
693 silc_schedule_internal_wakeup(schedule->internal);
694 SILC_SCHEDULE_UNLOCK(schedule);
698 /* Returns the application specific context that was saved into the
699 scheduler in silc_schedule_init function. The context is also
700 returned to application in task callback functions, but this function
701 may be used to get it as well if needed. */
703 void *silc_schedule_get_context(SilcSchedule schedule)
705 return schedule->app_context;
708 /* Add new task to the scheduler */
710 SilcTask silc_schedule_task_add(SilcSchedule schedule, SilcUInt32 fd,
711 SilcTaskCallback callback, void *context,
712 long seconds, long useconds,
714 SilcTaskPriority priority)
720 if (!schedule->valid)
723 queue = SILC_SCHEDULE_GET_QUEUE(type);
725 /* If the task is generic task, we check whether this task has already
726 been registered. Generic tasks are registered only once and after that
727 the same task applies to all file descriptors to be registered. */
728 if (type == SILC_TASK_GENERIC) {
729 silc_mutex_lock(queue->lock);
731 SILC_LOG_DEBUG(("Registering new task, fd=%d type=%d priority=%d", fd,
735 SilcTask task = queue->task;
737 if ((task->callback == callback) && (task->context == context)) {
738 SILC_LOG_DEBUG(("Found matching generic task, using the match"));
740 silc_mutex_unlock(queue->lock);
742 /* Add the fd to be listened, the task found now applies to this
744 silc_schedule_set_listen_fd(schedule, fd, SILC_TASK_READ, FALSE);
748 if (queue->task == task->next)
755 silc_mutex_unlock(queue->lock);
758 newtask = silc_calloc(1, sizeof(*newtask));
762 SILC_LOG_DEBUG(("Registering new task %p, fd=%d type=%d priority=%d",
763 newtask, fd, type, priority));
766 newtask->context = context;
767 newtask->callback = callback;
768 newtask->valid = TRUE;
769 newtask->priority = priority;
770 newtask->type = type;
771 newtask->next = newtask;
772 newtask->prev = newtask;
774 /* Create timeout if marked to be timeout task */
775 if (((seconds + useconds) > 0) && (type == SILC_TASK_TIMEOUT)) {
776 silc_gettimeofday(&newtask->timeout);
777 newtask->timeout.tv_sec += seconds + (useconds / 1000000L);
778 newtask->timeout.tv_usec += (useconds % 1000000L);
779 if (newtask->timeout.tv_usec > 999999L) {
780 newtask->timeout.tv_sec += 1;
781 newtask->timeout.tv_usec -= 1000000L;
786 /* If the task is non-timeout task we have to tell the scheduler that we
787 would like to have these tasks scheduled at some odd distant future. */
788 if (type != SILC_TASK_TIMEOUT)
789 silc_schedule_set_listen_fd(schedule, fd, SILC_TASK_READ, FALSE);
791 silc_mutex_lock(queue->lock);
793 /* Is this first task of the queue? */
794 if (queue->task == NULL) {
795 queue->task = newtask;
796 silc_mutex_unlock(queue->lock);
801 newtask = silc_task_add_timeout(queue, newtask, priority);
803 newtask = silc_task_add(queue, newtask, priority);
805 silc_mutex_unlock(queue->lock);
810 /* Removes a task from the scheduler */
812 void silc_schedule_task_del(SilcSchedule schedule, SilcTask task)
814 SilcTaskQueue queue = SILC_SCHEDULE_GET_QUEUE(task->type);
816 /* Unregister all tasks */
817 if (task == SILC_ALL_TASKS) {
819 SILC_LOG_DEBUG(("Unregistering all tasks at once"));
821 silc_mutex_lock(queue->lock);
824 silc_mutex_unlock(queue->lock);
833 if (queue->task == next->next)
838 silc_mutex_unlock(queue->lock);
842 SILC_LOG_DEBUG(("Unregistering task"));
844 silc_mutex_lock(queue->lock);
846 /* Unregister the specific task */
850 silc_mutex_unlock(queue->lock);
853 /* Remove task by fd */
855 void silc_schedule_task_del_by_fd(SilcSchedule schedule, SilcUInt32 fd)
857 SILC_LOG_DEBUG(("Unregister task by fd %d", fd));
859 silc_task_del_by_fd(schedule->timeout_queue, fd);
860 silc_task_del_by_fd(schedule->fd_queue, fd);
863 /* Remove task by task callback. */
865 void silc_schedule_task_del_by_callback(SilcSchedule schedule,
866 SilcTaskCallback callback)
868 SILC_LOG_DEBUG(("Unregister task by callback"));
870 silc_task_del_by_callback(schedule->timeout_queue, callback);
871 silc_task_del_by_callback(schedule->fd_queue, callback);
872 silc_task_del_by_callback(schedule->generic_queue, callback);
875 /* Remove task by context. */
877 void silc_schedule_task_del_by_context(SilcSchedule schedule, void *context)
879 SILC_LOG_DEBUG(("Unregister task by context"));
881 silc_task_del_by_context(schedule->timeout_queue, context);
882 silc_task_del_by_context(schedule->fd_queue, context);
883 silc_task_del_by_context(schedule->generic_queue, context);
886 /* Sets a file descriptor to be listened by select() in scheduler. One can
887 call this directly if wanted. This can be called multiple times for
888 one file descriptor to set different iomasks. */
890 void silc_schedule_set_listen_fd(SilcSchedule schedule, SilcUInt32 fd,
891 SilcTaskEvent mask, bool send_events)
896 if (!schedule->valid)
899 SILC_SCHEDULE_LOCK(schedule);
901 for (i = 0; i < schedule->max_fd; i++)
902 if (schedule->fd_list[i].fd == fd) {
903 schedule->fd_list[i].fd = fd;
904 schedule->fd_list[i].events = mask;
905 if (i > schedule->last_fd)
906 schedule->last_fd = i;
909 schedule->fd_list[i].revents = mask;
910 silc_schedule_dispatch_nontimeout(schedule);
916 for (i = 0; i < schedule->max_fd; i++)
917 if (schedule->fd_list[i].events == 0) {
918 schedule->fd_list[i].fd = fd;
919 schedule->fd_list[i].events = mask;
920 if (i > schedule->last_fd)
921 schedule->last_fd = i;
923 schedule->fd_list[i].revents = mask;
924 silc_schedule_dispatch_nontimeout(schedule);
929 SILC_SCHEDULE_UNLOCK(schedule);
932 /* Removes a file descriptor from listen list. */
934 void silc_schedule_unset_listen_fd(SilcSchedule schedule, SilcUInt32 fd)
938 SILC_SCHEDULE_LOCK(schedule);
940 SILC_LOG_DEBUG(("Unset listen fd %d", fd));
942 for (i = 0; i < schedule->max_fd; i++)
943 if (schedule->fd_list[i].fd == fd) {
944 schedule->fd_list[i].fd = 0;
945 schedule->fd_list[i].events = 0;
946 if (schedule->last_fd == i)
947 schedule->last_fd = schedule->max_fd - 1;
951 SILC_SCHEDULE_UNLOCK(schedule);
954 /* Register a new signal */
956 void silc_schedule_signal_register(SilcSchedule schedule, SilcUInt32 signal,
957 SilcTaskCallback callback, void *context)
959 silc_schedule_internal_signal_register(schedule->internal, signal,
963 /* Unregister a new signal */
965 void silc_schedule_signal_unregister(SilcSchedule schedule, SilcUInt32 signal,
966 SilcTaskCallback callback, void *context)
968 silc_schedule_internal_signal_unregister(schedule->internal, signal,
972 /* Call signal indicated by `signal'. */
974 void silc_schedule_signal_call(SilcSchedule schedule, SilcUInt32 signal)
976 /* Mark that signals needs to be delivered later. */
977 silc_schedule_internal_signal_call(schedule->internal, signal);
978 schedule->signal_tasks = TRUE;
981 /* Allocates a newtask task queue into the scheduler */
983 static void silc_task_queue_alloc(SilcTaskQueue *queue)
985 *queue = silc_calloc(1, sizeof(**queue));
986 silc_mutex_alloc(&(*queue)->lock);
989 /* Free's a task queue. */
991 static void silc_task_queue_free(SilcTaskQueue queue)
993 silc_mutex_free(queue->lock);
994 memset(queue, 'F', sizeof(*queue));
998 /* Return task by its fd. */
1000 static SilcTask silc_task_find(SilcTaskQueue queue, SilcUInt32 fd)
1012 if (queue->task == next->next)
1020 /* Adds a non-timeout task into the task queue. This function is used
1021 by silc_task_register function. Returns a pointer to the registered
1024 static SilcTask silc_task_add(SilcTaskQueue queue, SilcTask newtask,
1025 SilcTaskPriority priority)
1027 SilcTask task, next, prev;
1029 /* Take the first task in the queue */
1033 case SILC_TASK_PRI_LOW:
1034 /* Lowest priority. The task is added at the end of the list. */
1036 newtask->prev = prev;
1037 newtask->next = task;
1038 prev->next = newtask;
1039 task->prev = newtask;
1041 case SILC_TASK_PRI_NORMAL:
1042 /* Normal priority. The task is added before lower priority tasks
1043 but after tasks with higher priority. */
1045 while(prev != task) {
1046 if (prev->priority > SILC_TASK_PRI_LOW)
1051 /* There are only lower priorities in the list, we will
1052 sit before them and become the first task in the queue. */
1054 newtask->prev = prev;
1055 newtask->next = task;
1056 task->prev = newtask;
1057 prev->next = newtask;
1059 /* We are now the first task in queue */
1060 queue->task = newtask;
1062 /* Found a spot from the list, add the task to the list. */
1064 newtask->prev = prev;
1065 newtask->next = next;
1066 prev->next = newtask;
1067 next->prev = newtask;
1078 /* Return the timeout task with smallest timeout. */
1080 static SilcTask silc_task_get_first(SilcTaskQueue queue, SilcTask first)
1082 SilcTask prev, task;
1094 if (silc_compare_timeval(&prev->timeout, &task->timeout))
1103 /* Adds a timeout task into the task queue. This function is used by
1104 silc_task_register function. Returns a pointer to the registered
1105 task. Timeout tasks are sorted by their timeout value in ascending
1106 order. The priority matters if there are more than one task with
1109 static SilcTask silc_task_add_timeout(SilcTaskQueue queue, SilcTask newtask,
1110 SilcTaskPriority priority)
1112 SilcTask task, prev, next;
1114 /* Take the first task in the queue */
1117 /* Take last task from the list */
1121 case SILC_TASK_PRI_LOW:
1122 /* Lowest priority. The task is added at the end of the list. */
1123 while(prev != task) {
1125 /* If we have longer timeout than with the task head of us
1126 we have found our spot. */
1127 if (silc_compare_timeval(&prev->timeout, &newtask->timeout))
1130 /* If we are equal size of timeout we will be after it. */
1131 if (!silc_compare_timeval(&newtask->timeout, &prev->timeout))
1134 /* We have shorter timeout, compare to next one. */
1137 /* Found a spot from the list, add the task to the list. */
1139 newtask->prev = prev;
1140 newtask->next = next;
1141 prev->next = newtask;
1142 next->prev = newtask;
1145 /* Check if we are going to be the first task in the queue */
1146 if (silc_compare_timeval(&prev->timeout, &newtask->timeout))
1148 if (!silc_compare_timeval(&newtask->timeout, &prev->timeout))
1151 /* We are now the first task in queue */
1152 queue->task = newtask;
1155 case SILC_TASK_PRI_NORMAL:
1156 /* Normal priority. The task is added before lower priority tasks
1157 but after tasks with higher priority. */
1158 while(prev != task) {
1160 /* If we have longer timeout than with the task head of us
1161 we have found our spot. */
1162 if (silc_compare_timeval(&prev->timeout, &newtask->timeout))
1165 /* If we are equal size of timeout, priority kicks in place. */
1166 if (!silc_compare_timeval(&newtask->timeout, &prev->timeout))
1167 if (prev->priority >= SILC_TASK_PRI_NORMAL)
1170 /* We have shorter timeout or higher priority, compare to next one. */
1173 /* Found a spot from the list, add the task to the list. */
1175 newtask->prev = prev;
1176 newtask->next = next;
1177 prev->next = newtask;
1178 next->prev = newtask;
1181 /* Check if we are going to be the first task in the queue */
1182 if (silc_compare_timeval(&prev->timeout, &newtask->timeout))
1184 if (!silc_compare_timeval(&newtask->timeout, &prev->timeout))
1185 if (prev->priority >= SILC_TASK_PRI_NORMAL)
1188 /* We are now the first task in queue */
1189 queue->task = newtask;
1200 /* Removes (unregisters) a task from particular task queue. This function
1201 is used internally by scheduler. This must be called holding the
1204 static int silc_schedule_task_remove(SilcTaskQueue queue, SilcTask task)
1206 SilcTask first, old, next;
1208 if (!queue || !task)
1215 first = queue->task;
1217 /* Unregister all tasks in queue */
1218 if (task == SILC_ALL_TASKS) {
1219 SILC_LOG_DEBUG(("Removing all tasks at once"));
1234 SILC_LOG_DEBUG(("Removing task %p", task));
1236 /* Unregister the task */
1240 SilcTask prev, next;
1247 if (prev == old && next == old)
1249 if (queue->task == old)
1250 queue->task = silc_task_get_first(queue, next);
1263 static void silc_task_del_by_fd(SilcTaskQueue queue, SilcUInt32 fd)
1267 silc_mutex_lock(queue->lock);
1270 silc_mutex_unlock(queue->lock);
1278 next->valid = FALSE;
1279 if (queue->task == next->next)
1284 silc_mutex_unlock(queue->lock);
1287 static void silc_task_del_by_callback(SilcTaskQueue queue,
1288 SilcTaskCallback callback)
1292 silc_mutex_lock(queue->lock);
1295 silc_mutex_unlock(queue->lock);
1302 if (next->callback == callback)
1303 next->valid = FALSE;
1304 if (queue->task == next->next)
1309 silc_mutex_unlock(queue->lock);
1312 static void silc_task_del_by_context(SilcTaskQueue queue, void *context)
1316 silc_mutex_lock(queue->lock);
1319 silc_mutex_unlock(queue->lock);
1326 if (next->context == context)
1327 next->valid = FALSE;
1328 if (queue->task == next->next)
1333 silc_mutex_unlock(queue->lock);