5 Author: Pekka Riikonen <priikone@silcnet.org>
7 Copyright (C) 2005 - 2007 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.
22 SILC_TASK_CALLBACK(silc_fsm_run);
23 SILC_TASK_CALLBACK(silc_fsm_finish_fsm);
24 SILC_TASK_CALLBACK(silc_fsm_event_timedout);
25 SILC_TASK_CALLBACK(silc_fsm_start_real_thread);
26 static void silc_fsm_thread_termination_signal(SilcFSMEvent event);
27 static void silc_fsm_event_ref(SilcFSMEvent event);
28 static void silc_fsm_event_unref(SilcFSMEvent event);
29 void *silc_fsm_thread(void *context);
33 SilcFSM silc_fsm_alloc(void *fsm_context,
34 SilcFSMDestructor destructor,
35 void *destructor_context,
36 SilcSchedule schedule)
40 fsm = silc_calloc(1, sizeof(*fsm));
41 if (silc_unlikely(!fsm))
44 if (silc_unlikely(!silc_fsm_init(fsm, fsm_context, destructor,
45 destructor_context, schedule))) {
55 SilcBool silc_fsm_init(SilcFSM fsm,
57 SilcFSMDestructor destructor,
58 void *destructor_context,
59 SilcSchedule schedule)
64 fsm->fsm_context = fsm_context;
65 fsm->state_context = NULL;
66 fsm->destructor = destructor;
67 fsm->destructor_context = destructor_context;
68 fsm->schedule = schedule;
70 fsm->async_call = FALSE;
73 silc_atomic_init32(&fsm->u.m.threads, 0);
78 /* Allocate FSM thread. Internally machine and thread use same context. */
80 SilcFSMThread silc_fsm_thread_alloc(SilcFSM fsm,
82 SilcFSMThreadDestructor destructor,
83 void *destructor_context,
88 thread = silc_calloc(1, sizeof(*thread));
89 if (silc_unlikely(!thread))
92 silc_fsm_thread_init(thread, fsm, thread_context, destructor,
93 destructor_context, real_thread);
97 /* Initialize FSM thread. Internally machine and thread use same context. */
99 void silc_fsm_thread_init(SilcFSMThread thread,
101 void *thread_context,
102 SilcFSMThreadDestructor destructor,
103 void *destructor_context,
104 SilcBool real_thread)
106 SILC_LOG_DEBUG(("Initializing new thread %p (%s)",
107 thread, real_thread ? "real" : "FSM"));
109 SILC_ASSERT(!fsm->thread);
111 thread->fsm_context = thread_context;
112 thread->state_context = NULL;
113 thread->destructor = (SilcFSMDestructor)destructor;
114 thread->destructor_context = destructor_context;
115 thread->schedule = fsm->schedule;
116 thread->thread = TRUE;
117 thread->async_call = FALSE;
118 thread->started = FALSE;
119 thread->real_thread = real_thread;
120 thread->u.t.fsm = fsm;
123 silc_atomic_add_int32(&fsm->u.m.threads, 1);
125 /* Allocate lock for the machine if using real threads. */
126 if (real_thread && !fsm->u.m.lock)
127 if (!silc_mutex_alloc(&fsm->u.m.lock))
128 thread->real_thread = FALSE;
131 /* FSM is destroyed through scheduler to make sure that all dying
132 real system threads will have their finish callbacks scheduled before
133 this one (when SILC_FSM_THREAD_WAIT was used). */
135 SILC_TASK_CALLBACK(silc_fsm_free_final)
139 #if defined(SILC_DEBUG)
140 /* We must be finished */
141 SILC_ASSERT(f->finished);
143 /* Machine must not have active threads */
144 if (!f->thread && silc_atomic_get_int32(&f->u.m.threads))
145 SILC_ASSERT(silc_atomic_get_int32(&f->u.m.threads) == 0);
146 #endif /* SILC_DEBUG */
148 if (!f->thread && f->u.m.lock)
149 silc_mutex_free(f->u.m.lock);
151 if (f->thread && f->u.t.event)
152 silc_fsm_event_free(f->u.t.event);
155 silc_atomic_uninit32(&f->u.m.threads);
162 void silc_fsm_free(void *fsm)
166 if (silc_schedule_task_add_timeout(f->schedule, silc_fsm_free_final,
169 silc_fsm_free_final(f->schedule, silc_schedule_get_context(f->schedule),
173 /* Task to start real thread. We start threads through scheduler, not
174 directly in silc_fsm_start. */
176 SILC_TASK_CALLBACK(silc_fsm_start_real_thread)
181 if (silc_thread_create(silc_fsm_thread, f, FALSE))
183 #endif /* SILC_THREADS */
185 SILC_LOG_DEBUG(("Could not create real thread, using normal FSM thread"));
187 /* Normal FSM operation */
188 f->real_thread = FALSE;
189 silc_fsm_continue_sync(f);
192 /* Start FSM in the specified state */
194 void silc_fsm_start(void *fsm, SilcFSMStateCallback start_state)
198 SILC_LOG_DEBUG(("Starting %s %p", f->thread ? "thread" : "FSM", fsm));
201 f->next_state = start_state;
202 f->synchronous = FALSE;
205 /* Start real thread through scheduler */
206 if (f->thread && f->real_thread) {
207 if (!silc_schedule_task_add_timeout(f->schedule,
208 silc_fsm_start_real_thread,
210 silc_fsm_start_real_thread(f->schedule,
211 silc_schedule_get_context(f->schedule),
213 silc_schedule_wakeup(f->schedule);
217 /* Normal FSM operation */
218 if (!silc_schedule_task_add_timeout(f->schedule, silc_fsm_run, f, 0, 0))
219 silc_fsm_run(f->schedule, silc_schedule_get_context(f->schedule), 0, 0, f);
221 /* Wakeup scheduler in case we are starting this thread from another
224 silc_schedule_wakeup(f->schedule);
227 /* Start FSM in the specified state synchronously */
229 void silc_fsm_start_sync(void *fsm, SilcFSMStateCallback start_state)
233 SILC_LOG_DEBUG(("Starting %s %p", f->thread ? "thread" : "FSM", fsm));
236 f->next_state = start_state;
237 f->synchronous = TRUE;
240 /* Start real thread directly */
241 if (f->thread && f->real_thread) {
242 silc_fsm_start_real_thread(f->schedule,
243 silc_schedule_get_context(f->schedule),
248 /* Normal FSM operation */
249 silc_fsm_run(f->schedule, silc_schedule_get_context(f->schedule), 0, 0, f);
252 /* Set next FSM state */
254 void silc_fsm_next(void *fsm, SilcFSMStateCallback next_state)
257 f->next_state = next_state;
260 /* Continue after timeout */
262 void silc_fsm_next_later(void *fsm, SilcFSMStateCallback next_state,
263 SilcUInt32 seconds, SilcUInt32 useconds)
267 f->next_state = next_state;
268 if (!seconds && !useconds)
271 silc_schedule_task_add_timeout(f->schedule, silc_fsm_run, f,
273 f->next_later = TRUE;
275 /* Wakeup up the scheduler just in case this was called from another
277 silc_schedule_wakeup(f->schedule);
280 /* Continue after callback or async operation */
282 void silc_fsm_continue(void *fsm)
287 /* Cancel next_later timeout */
288 silc_schedule_task_del_by_all(f->schedule, 0, silc_fsm_run, f);
289 f->next_later = FALSE;
292 if (!silc_schedule_task_add_timeout(f->schedule, silc_fsm_run, f, 0, 0))
293 silc_fsm_run(f->schedule, silc_schedule_get_context(f->schedule), 0, 0, f);
295 /* Wakeup up the scheduler just in case this was called from another
297 silc_schedule_wakeup(f->schedule);
300 /* Continue after callback or async operation immediately */
302 void silc_fsm_continue_sync(void *fsm)
306 silc_schedule_task_del_by_all(f->schedule, 0, silc_fsm_run, f);
307 f->next_later = FALSE;
309 silc_fsm_run(f->schedule, silc_schedule_get_context(f->schedule), 0, 0, f);
314 void silc_fsm_finish(void *fsm)
318 SILC_ASSERT(!f->finished);
323 silc_schedule_task_del_by_all(f->schedule, 0, silc_fsm_run, f);
324 f->next_later = FALSE;
326 /* If we are thread and using real threads, the FSM thread will finish
327 after the real thread has finished, in the main thread. */
328 if (f->thread && f->real_thread) {
329 /* Stop the real thread's scheduler to finish the thread */
330 silc_schedule_stop(f->schedule);
331 silc_schedule_wakeup(f->schedule);
335 /* Normal FSM operation */
337 if (silc_schedule_task_add_timeout(f->schedule, silc_fsm_finish_fsm,
341 silc_fsm_finish_fsm(f->schedule, silc_schedule_get_context(f->schedule),
345 /* Return associated scheduler */
347 SilcSchedule silc_fsm_get_schedule(void *fsm)
353 /* Return thread's machine */
355 SilcFSM silc_fsm_get_machine(SilcFSMThread thread)
357 SILC_ASSERT(thread->thread);
358 return (SilcFSM)thread->u.t.fsm;
361 /* Returns TRUE if FSM is started */
363 SilcBool silc_fsm_is_started(void *fsm)
371 void silc_fsm_set_context(void *fsm, void *fsm_context)
374 f->fsm_context = fsm_context;
379 void *silc_fsm_get_context(void *fsm)
382 return f->fsm_context;
385 /* Set state context */
387 void silc_fsm_set_state_context(void *fsm, void *state_context)
390 f->state_context = state_context;
393 /* Get state context */
395 void *silc_fsm_get_state_context(void *fsm)
398 return f->state_context;
401 /* Wait for thread to terminate */
403 SilcBool silc_fsm_thread_wait(void *fsm, void *thread)
407 SILC_ASSERT(t->thread);
409 t->u.t.event = silc_fsm_event_alloc(t->u.t.fsm);
413 SILC_LOG_DEBUG(("Waiting for thread %p to terminate", thread));
414 silc_fsm_event_wait(t->u.t.event, fsm);
420 SILC_TASK_CALLBACK(silc_fsm_run)
422 SilcFSM fsm = context;
423 SilcFSMStatus status;
425 SILC_LOG_DEBUG(("Running %s %p", fsm->thread ? "thread" : "FSM", fsm));
429 status = fsm->next_state(fsm, fsm->fsm_context, fsm->state_context);
430 while (status == SILC_FSM_ST_CONTINUE);
433 case SILC_FSM_ST_YIELD:
434 /* Continue through scheduler */
435 silc_fsm_continue(fsm);
438 case SILC_FSM_ST_WAIT:
439 /* The machine is in hold */
440 SILC_LOG_DEBUG(("State wait %p", fsm));
441 fsm->synchronous = FALSE;
444 case SILC_FSM_ST_FINISH:
445 /* Finish the state machine */
446 SILC_LOG_DEBUG(("State finish %p", fsm));
447 silc_fsm_finish(fsm);
455 /* Finishes the FSM. This is always executed in the main thread, even
456 for FSM threads that were run in real threads. */
458 SILC_TASK_CALLBACK(silc_fsm_finish_fsm)
460 SilcFSM fsm = context;
462 SILC_LOG_DEBUG(("%s %p, is finished", fsm->thread ? "Thread" : "FSM", fsm));
464 fsm->next_state = NULL;
467 /* This is thread, send signal */
468 if (fsm->u.t.event) {
469 silc_fsm_thread_termination_signal(fsm->u.t.event);
470 silc_fsm_event_free(fsm->u.t.event);
471 fsm->u.t.event = NULL;
474 /* Remove the thread from machine */
475 silc_atomic_sub_int32(&fsm->u.t.fsm->u.m.threads, 1);
477 /* Call the destructor callback only if the underlaying machine is
479 if (fsm->destructor && fsm->u.t.fsm->finished == FALSE)
480 fsm->destructor(fsm, fsm->fsm_context, fsm->destructor_context);
483 /* Machine must not have active threads */
484 assert(silc_atomic_get_int32(&fsm->u.m.threads) == 0);
487 silc_mutex_free(fsm->u.m.lock);
488 fsm->u.m.lock = NULL;
491 /* Call the destructor callback. */
493 fsm->destructor(fsm, fsm->fsm_context, fsm->destructor_context);
497 /* Allocate FSM event */
499 SilcFSMEvent silc_fsm_event_alloc(SilcFSM fsm)
503 event = silc_calloc(1, sizeof(*event));
504 if (silc_unlikely(!event))
507 silc_fsm_event_init(event, fsm);
508 event->allocated = TRUE;
513 /* Initializes FSM event */
515 void silc_fsm_event_init(SilcFSMEvent event, SilcFSM fsm)
517 SILC_LOG_DEBUG(("Initializing event %p", event));
518 SILC_ASSERT(!fsm->thread);
519 memset(event, 0, sizeof(*event));
522 silc_list_init(event->waiters, struct SilcFSMObject, next);
527 void silc_fsm_event_free(SilcFSMEvent event)
529 if (event->refcnt > 0)
531 if (silc_list_count(event->waiters) > 0)
536 /* Reference event */
538 static void silc_fsm_event_ref(SilcFSMEvent event)
543 /* Unreference event */
545 static void silc_fsm_event_unref(SilcFSMEvent event)
548 if (event->refcnt == 0 && event->allocated)
549 silc_fsm_event_free(event);
552 /* Wait until event is non-zero. */
554 SilcUInt32 silc_fsm_event_wait(SilcFSMEvent event, void *fsm)
556 SilcMutex lock = event->fsm->u.m.lock;
558 silc_mutex_lock(lock);
561 #if defined(SILC_DEBUG)
563 silc_list_start(event->waiters);
564 while ((entry = silc_list_get(event->waiters)))
565 SILC_ASSERT(entry != fsm);
566 #endif /* SILC_DEBUG */
568 SILC_LOG_DEBUG(("Waiting for event %p", event));
570 /* Add the FSM to waiter list */
571 silc_list_add(event->waiters, fsm);
572 silc_mutex_unlock(lock);
576 SILC_LOG_DEBUG(("Received event %p", event));
578 /* Remove from waiting */
579 silc_list_del(event->waiters, fsm);
581 /* Decrease the counter only after all waiters have acquired the signal. */
582 if (!silc_list_count(event->waiters))
585 silc_mutex_unlock(lock);
589 /* Wait util event is non-zero, or timeout occurs. */
591 SilcUInt32 silc_fsm_event_timedwait(SilcFSMEvent event, void *fsm,
592 SilcUInt32 seconds, SilcUInt32 useconds,
595 SilcMutex lock = event->fsm->u.m.lock;
599 silc_mutex_lock(lock);
601 if (f->event_timedout) {
602 SILC_LOG_DEBUG(("Event waiting timedout"));
603 f->event_timedout = FALSE;
606 silc_mutex_unlock(lock);
610 silc_mutex_unlock(lock);
612 value = silc_fsm_event_wait(event, fsm);
614 silc_schedule_task_add_timeout(f->schedule, silc_fsm_event_timedout,
615 f, seconds, useconds);
627 SILC_TASK_CALLBACK(silc_fsm_event_timedout)
629 SilcFSM fsm = context;
630 SilcMutex lock = fsm->event->fsm->u.m.lock;
632 SILC_LOG_DEBUG(("Event %p timedout", fsm->event));
634 /* Remove the waiter from the event waiters list */
635 silc_mutex_lock(lock);
636 silc_list_del(fsm->event->waiters, fsm);
640 silc_fsm_continue(fsm);
641 fsm->event_timedout = TRUE;
645 silc_mutex_unlock(lock);
648 /* Signalled, event */
650 SILC_TASK_CALLBACK(silc_fsm_signal)
652 SilcFSMEventSignal p = context;
653 SilcMutex lock = p->event->fsm->u.m.lock;
656 /* We have to check for couple of things before delivering the signal. */
658 /* If the event value has went to zero while we've been waiting this
659 callback, the event has been been signalled already. It can happen
660 when using real threads because the FSM may not be in waiting state
661 when the event is signalled. */
662 silc_mutex_lock(lock);
663 if (!p->event->value) {
664 silc_mutex_unlock(lock);
665 silc_fsm_event_unref(p->event);
670 /* If the waiter is not waiting anymore, don't deliver the signal. It
671 can happen if there were multiple signallers and the waiter went away
672 after the first signal. */
673 silc_list_start(p->event->waiters);
674 while ((fsm = silc_list_get(p->event->waiters)))
678 silc_mutex_unlock(lock);
679 silc_fsm_event_unref(p->event);
683 silc_mutex_unlock(lock);
685 SILC_LOG_DEBUG(("Signalled %s %p", p->fsm->thread ? "thread" : "FSM",
689 silc_fsm_continue_sync(p->fsm);
691 silc_fsm_event_unref(p->event);
697 void silc_fsm_event_signal(SilcFSMEvent event)
700 SilcFSMEventSignal p;
701 SilcMutex lock = event->fsm->u.m.lock;
703 SILC_LOG_DEBUG(("Signal event %p", event));
705 silc_mutex_lock(lock);
708 silc_list_start(event->waiters);
709 while ((fsm = silc_list_get(event->waiters))) {
711 silc_schedule_task_del_by_all(fsm->schedule, 0, silc_fsm_event_timedout,
716 p = silc_calloc(1, sizeof(*p));
717 if (silc_unlikely(!p))
721 silc_fsm_event_ref(event);
723 /* Signal through scheduler. Wake up destination scheduler in case
724 caller is a real thread. */
725 silc_schedule_task_add_timeout(fsm->schedule, silc_fsm_signal, p, 0, 0);
726 silc_schedule_wakeup(fsm->schedule);
729 silc_mutex_unlock(lock);
732 /* Post thread termination event. Special function used only to
733 signal thread termination when SILC_FSM_THREAD_WAIT was used. */
735 static void silc_fsm_thread_termination_signal(SilcFSMEvent event)
738 SilcMutex lock = event->fsm->u.m.lock;
740 SILC_LOG_DEBUG(("Post thread terminate event %p", event));
742 silc_mutex_lock(lock);
744 silc_list_start(event->waiters);
745 while ((fsm = silc_list_get(event->waiters))) {
746 /* Signal on thread termination. Wake up destination scheduler in case
747 caller is a real thread. */
748 silc_list_del(event->waiters, fsm);
749 silc_fsm_continue(fsm);
750 silc_schedule_wakeup(fsm->schedule);
753 silc_mutex_unlock(lock);
758 void *silc_fsm_thread(void *context)
760 SilcFSM fsm = context;
761 SilcSchedule old = fsm->schedule;
763 SILC_LOG_DEBUG(("Starting FSM thread in real thread"));
765 /* We allocate new SilcSchedule for the FSM, as the old SilcSchedule
766 cannot be used in this thread. Application may still use it if it
767 wants but we use our own. */
768 fsm->schedule = silc_schedule_init(0, old);
769 if (silc_unlikely(!fsm->schedule))
772 /* Start the FSM thread */
773 if (silc_unlikely(!silc_schedule_task_add_timeout(fsm->schedule,
774 silc_fsm_run, fsm, 0, 0)))
777 /* Run the scheduler */
778 silc_schedule(fsm->schedule);
781 silc_schedule_uninit(fsm->schedule);
785 /* Finish the FSM thread in the main thread */
786 SILC_ASSERT(fsm->finished);
787 silc_schedule_task_add_timeout(fsm->schedule, silc_fsm_finish_fsm,
789 silc_schedule_wakeup(fsm->schedule);