5 Author: Pekka Riikonen <priikone@silcnet.org>
7 Copyright (C) 2005, 2006 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.
20 /****h* silcutil/SILC Finite State Machine
24 * SILC FSM Interface implements a finite state machine. The FSM can be
25 * used to implement all kinds of machines and protocols. The FSM supports
26 * also threads and can be synchronized by using mutex locks. The FSM
27 * also supports real system threads. It is possible to create new FSM
28 * thread and then execute in real system thread, if platform supports
31 * The FSM provides also asynchronous events that can be used to wait for
32 * some events or states to occur. The FSM events may be used as condition
33 * variables and signallers. The FSM events can safely be used in FSM
34 * threads that are executed in real system threads.
36 * To synchronize machines that use FSM threads that are executed in real
37 * system threads the SILC Mutex API (silcmutex.h) may be used. Normal
38 * multi-threaded coding conventions apply when programming with real FSM
39 * threads. If the FSM threads are not real system threads, synchronization
47 /****s* silcutil/SilcFSMAPI/SilcFSM
51 * typedef struct SilcFSMObject *SilcFSM;
55 * The actual FSM context and is allocated with silc_fsm_alloc and
56 * given as argument to all silc_fsm_* functions. It is freed by
57 * silc_fsm_free function. It is also possible to use pre-allocated
58 * FSM context by using SilcFSMStruct instead of SilcFSM.
61 typedef struct SilcFSMObject *SilcFSM;
63 /****s* silcutil/SilcFSMAPI/SilcFSMStruct
67 * typedef struct SilcFSMObject SilcFSMStruct;
71 * The actual FSM context and can be used as pre-allocated FSM context,
72 * instead of SilcFSM context. This context is initialized with the
73 * silc_fsm_init function. It need not be uninitialized.
76 typedef struct SilcFSMObject SilcFSMStruct;
78 /****s* silcutil/SilcFSMAPI/SilcFSMThread
82 * typedef struct SilcFSMObject *SilcFSMThread;
86 * FSM thread context. The SILC FSM supports threads, virtual machine
87 * threads (inside FSM) and actual real system threads if platorm
88 * supports them. In a complex machine certain complex operations may
89 * be desired to execute in a thread. The SilcFSMThread is allocated
90 * by silc_fsm_thread_alloc and feed by silc_fsm_free. It is also
91 * possible to use pre-allocated thread by using SilcFSMThreadStruct
92 * instead of SilcFSMThread.
95 typedef struct SilcFSMObject *SilcFSMThread;
97 /****s* silcutil/SilcFSMAPI/SilcFSM
101 * typedef struct SilcFSMObject SilcFSMThreadStruct;
105 * FSM thread context and can be used as a pre-allocated FSM thread context,
106 * instead of SilcFSMThread context. This context is initialized with the
107 * silc_fsm_thread_init function. It need not be uninitialized.
110 typedef struct SilcFSMObject SilcFSMThreadStruct;
112 /****d* silcutil/SilcFSMAPI/SILC_FSM_CONTINUE
120 * Moves to next state synchronously. This macro is used in state
121 * functions to immediately move to next state. The state function
122 * returns in this macro. The macro has no arguments.
126 * SILC_FSM_STATE(silc_foo_state)
130 * // Move to next state now
131 * silc_fsm_next(fsm, silc_foo_next_state);
136 #define SILC_FSM_CONTINUE \
137 return fsm->next_state(fsm, fsm->fsm_context, fsm->state_context);
139 /****d* silcutil/SilcFSMAPI/SILC_FSM_YIELD
147 * Moves to next state through the machine scheduler. Other threads
148 * running in the machine will get running time with SILC_FSM_YIELD.
149 * When using real threads, using SILC_FSM_YIELD is usually unnecessary.
150 * The state function returns in this macro. The macro has no arguments.
153 #define SILC_FSM_YIELD return SILC_FSM_ST_YIELD;
155 /****d* silcutil/SilcFSMAPI/SILC_FSM_WAIT
163 * Suspends the machine or thread until it is awaken. This is used
164 * when asynchronous call is made or timer is set, or something else
165 * that requires waiting. The state function returns in this macro.
166 * The macro has no arguments.
169 #define SILC_FSM_WAIT return SILC_FSM_ST_WAIT
171 /****d* silcutil/SilcFSMAPI/SILC_FSM_FINISH
179 * Finishes the machine or thread and calls its destructor, if defined.
180 * If the machine is finished when it has running threads the machine
181 * will fatally fail. User must always finish the threads before
182 * finishing the machine. The macro has no arguments.
185 #define SILC_FSM_FINISH return SILC_FSM_ST_FINISH
187 /****f* silcutil/SilcFSMAPI/SilcFSMDestructor
191 * typedef void (*SilcFSMDestructor)(SilcFSM fsm, void *fsm_context,
192 * void *destructor_context);
196 * The destructor callback that was set in silc_fsm_alloc or in
197 * silc_fsm_init function. It will be called when a state function
198 * calls SILC_FSM_FINISH. This function will be called through
199 * the scheduler; it will not be called immediately after the state
200 * function calls SILC_FSM_FINISH, but will be called later. The `fsm'
201 * may be freed in this function.
204 typedef void (*SilcFSMDestructor)(SilcFSM fsm, void *fsm_context,
205 void *destructor_context);
207 /****f* silcutil/SilcFSMAPI/SilcFSMThreadDestructor
211 * typedef void (*SilcFSMThreadDestructor)(SilcFSMThread thread,
212 * void *thread_context,
213 * void *destructor_context);
217 * The destructor callback that was set in silc_fsm_thread_alloc or in
218 * silc_fsm_thread_init function. It will be called when a state function
219 * calls SILC_FSM_FINISH. This function will be called through the
220 * scheduler; it will not be called immediately after the state function
221 * calls SILC_FSM_FINISH, but will be called later. The `thread' may
222 * be freed in this function.
226 * Even if the `thread' was executed in real system thread, this callback
227 * is always received in the main machine thread, not in the created
231 typedef void (*SilcFSMThreadDestructor)(SilcFSMThread thread,
232 void *thread_context,
233 void *destructor_context);
235 /****d* silcutil/SilcFSMAPI/SILC_FSM_STATE
239 * #define SILC_FSM_STATE(name)
243 * This macro is used to declare an FSM state function. The `fsm' is
244 * the SilcFSM or SilcFSMThread context, the `fsm_context' is the context
245 * given as argument to silc_fsm_alloc, silc_fsm_init, silc_fsm_thread_init,
246 * or silc_fsm_thread_alloc function. The `state_context' is the optional
247 * state specific context set with silc_fsm_set_state_context function.
251 #define SILC_FSM_STATE(name) \
252 int name(struct SilcFSMObject *fsm, void *fsm_context, void *state_context)
255 /* State function callback */
256 typedef int (*SilcFSMStateCallback)(struct SilcFSMObject *fsm,
258 void *state_context);
260 /****d* silcutil/SilcFSMAPI/SILC_FSM_CALL
264 * SILC_FSM_CALL(function)
268 * Macro used to call asynchronous calls from state function. If the
269 * call is not really asynchronous then this will cause the machine to
270 * directly proceed to next state. If the call is truly asynchronous
271 * then this will set the machine to wait state. The silc_fsm_next
272 * must be called before this macro, so that the next state is set.
276 * The state function returns in this macro.
281 * silc_fsm_next(fsm, some_next_state);
282 * SILC_FSM_CALL(silc_some_async_call(server, some_callback, context));
284 * // More complex example
285 * silc_fsm_next(fsm, some_next_state);
286 * SILC_FSM_CALL((some_context->operation =
287 * silc_some_async_call(server, some_callback, context)));
290 #define SILC_FSM_CALL(function) \
292 assert(!silc_fsm_set_call(fsm, TRUE)); \
294 if (!silc_fsm_set_call(fsm, FALSE)) \
299 /****d* silcutil/SilcFSMAPI/SILC_FSM_CALL_CONTINUE
303 * SILC_FSM_CALL_CONTINUE(fsm)
307 * Macro used to proceed after asynchornous call. This is called in the
308 * callback of the asynchronous call to continue in the state machine.
312 * void some_callback(void *context) {
313 * SilcFSM fsm = context;
315 * // Continue to the next state
316 * SILC_FSM_CALL_CONTINUE(fsm);
320 #define SILC_FSM_CALL_CONTINUE(fsm) \
322 if (!silc_fsm_set_call(fsm, FALSE)) \
323 silc_fsm_continue(fsm); \
326 /****d* silcutil/SilcFSMAPI/SILC_FSM_CALL_CONTINUE_SYNC
330 * SILC_FSM_CALL_CONTINUE_SYNC(fsm)
334 * Macro used to proceed after asynchornous call. This is called in the
335 * callback of the asynchronous call to continue in the state machine.
336 * This continues to the next state synchronously, not through the
341 * void some_callback(void *context) {
342 * SilcFSM fsm = context;
344 * // Continue to the next state immediately
345 * SILC_FSM_CALL_CONTINUE_SYNC(fsm);
349 #define SILC_FSM_CALL_CONTINUE_SYNC(fsm) \
351 if (!silc_fsm_set_call(fsm, FALSE)) \
352 silc_fsm_continue_sync(fsm); \
355 /****d* silcutil/SilcFSMAPI/SILC_FSM_THREAD_WAIT
359 * SILC_FSM_THREAD_WAIT(thread)
363 * Macro used to wait for the `thread' to terminate. The machine or
364 * thread will be suspended while it is waiting for the thread to
369 * The state function returns in this macro.
371 * This macro is the only way to safely make sure that the thread has
372 * terminated by the time FSM continues from the waiting state. Using
373 * FSM events to signal from the thread before SILC_FSM_FINISH is called
374 * works with normal FSM threads, but especially with real system threads
375 * it does not guarantee that the FSM won't continue before the thread has
376 * actually terminated. Usually this is not a problem, but it can be a
377 * problem if the FSM is waiting to be freed. In this case using this
378 * macro is strongly recommended.
381 #define SILC_FSM_THREAD_WAIT(thread) \
383 silc_fsm_thread_wait(fsm, thread); \
387 /****f* silcutil/SilcFSMAPI/silc_fsm_alloc
391 * SilcFSM silc_fsm_alloc(void *fsm_context,
392 * SilcFSMDestructor destructor,
393 * void *destructor_context,
394 * SilcSchedule schedule);
398 * Allocates SILC Finite State Machine context. The `destructor' with
399 * `destructor_context' will be called when the machines finishes. The
400 * caller must free the returned context with silc_fsm_free. The
401 * `fsm_context' is delivered to every FSM state function. The `schedule'
402 * is the caller's scheduler and the FSM will be run in the scheduler.
406 * SilcAsyncOperation silc_async_call(Callback callback, void *cb_context)
408 * SilcAsyncOperation op;
412 * // Allocate async operation so that caller can control us, like abort
413 * op = silc_async_alloc(silc_async_call_abort, NULL, ourcontext);
416 * fsm = silc_fsm_alloc(ourcontext, fsm_destructor, ourcontext,
418 * silc_fsm_start(fsm, first_state);
421 * // Return async operation for upper layer
426 SilcFSM silc_fsm_alloc(void *fsm_context,
427 SilcFSMDestructor destructor,
428 void *destructor_context,
429 SilcSchedule schedule);
431 /****f* silcutil/SilcFSMAPI/silc_fsm_init
435 * SilcBool silc_fsm_init(SilcFSM fsm,
437 * SilcFSMDestructor destructor,
438 * void *destructor_context,
439 * SilcSchedule schedule);
443 * Initializes a pre-allocated SilcFSM context. This call is equivalent
444 * to silc_fsm_alloc except that this takes the pre-allocated context
445 * as argument. The silc_fsm_free must not be called if this was called.
446 * Returns TRUE if the initialization is Ok or FALSE if error occurred.
447 * This function does not allocate any memory. The `schedule' is the
448 * caller's scheduler and the FSM will be run in the scheduler.
454 * silc_fsm_init(&fsm, application, fsm_destructor, application, schedule);
455 * silc_fsm_start(&fsm, first_state);
458 SilcBool silc_fsm_init(SilcFSM fsm,
460 SilcFSMDestructor destructor,
461 void *destructor_context,
462 SilcSchedule schedule);
464 /****f* silcutil/SilcFSMAPI/silc_fsm_thread_alloc
468 * SilcFSMThread silc_fsm_thread_alloc(SilcFSM fsm,
469 * void *thread_context,
470 * SilcFSMThreadDestructor destructor,
471 * void *destructor_context,
472 * SilcBool real_thread);
476 * Allocates FSM thread context. The thread will be executed in the
477 * FSM machine indicated by `fsm'. The caller must free the returned
478 * thread context with silc_fsm_free. If the 'real_thread' is TRUE
479 * then the thread will actually be executed in real thread, if platform
480 * supports them. The `thread_context' is delivered to every state
481 * function in the thread.
485 * If the system does not support threads, then this function will revert
486 * back to normal FSM threads.
488 * If the `real_thread' is TRUE then FSM will allocate new SilcSchedule
489 * for the FSM thread. If you need scheduler in the real thread it is
490 * strongly recommended that you use the SilcSchedule that is allocated
491 * for the thread. You can retrieve the SilcSchedule from the thread
492 * using silc_fsm_get_schedule function. Note that, the allocated
493 * SilcSchedule will become invalid after the thread finishes.
495 * If `real_thread' is FALSE the silc_fsm_get_schedule will return
496 * the SilcSchedule that was originally given to silc_fsm_alloc or
501 * SILC_FSM_STATE(silc_foo_state)
503 * SilcFSMThread thread;
506 * // Execute the route lookup in thread
507 * thread = silc_fsm_thread_alloc(fsm, fsm_context, NULL, NULL, FALSE);
508 * silc_fsm_start(thread, silc_route_lookup_start);
510 * // Wait here for the thread to terminate. Set the state where to go
511 * // after the thread has terminated.
512 * silc_fsm_next(fsm, silc_foo_route_lookup_finished);
513 * SILC_FSM_THREAD_WAIT(thread);
517 SilcFSMThread silc_fsm_thread_alloc(SilcFSM fsm,
518 void *thread_context,
519 SilcFSMThreadDestructor destructor,
520 void *destructor_context,
521 SilcBool real_thread);
523 /****f* silcutil/SilcFSMAPI/silc_fsm_thread_init
527 * void silc_fsm_thread_init(SilcFSMThread thread,
529 * void *thread_context,
530 * SilcFSMThreadDestructor destructor,
531 * void *destructor_context,
532 * SilcBool real_thread);
536 * Initializes a pre-allocated SilcFSMThread context. This call is
537 * equivalent to silc_fsm_thread_alloc except that this takes the
538 * pre-allocated context as argument. The silc_fsm_free must not be
539 * called if this was called. If the `real_thread' is TRUE then the
540 * thread will actually be executed in real thread, if platform supports
545 * See the notes from the silc_fsm_thread_alloc.
549 * SilcFSMThreadStruct thread;
551 * silc_fsm_thread_init(&thread, fsm, application, NULL, NULL, FALSE);
552 * silc_fsm_start(&thread, first_state);
555 void silc_fsm_thread_init(SilcFSMThread thread,
557 void *thread_context,
558 SilcFSMThreadDestructor destructor,
559 void *destructor_context,
560 SilcBool real_thread);
562 /****f* silcutil/SilcFSMAPI/silc_fsm_free
566 * void silc_fsm_free(void *fsm);
570 * Free the SILC FSM context that was allocated with silc_fsm_alloc,
571 * or free the SILC FSM thread context that was allocated with
572 * silc_fsm_thread_alloc. This function is used with both SilcFSM
573 * and SilcFSMThread contexts.
577 * When freeing FSM, it must not have any active threads.
580 void silc_fsm_free(void *fsm);
582 /****f* silcutil/SilcFSMAPI/silc_fsm_start
586 * void silc_fsm_start(void *fsm, SilcFSMStateCallback start_state);
590 * This function must be called after the SILC FSM context was created.
591 * This actually starts the state machine. Note that, the machine is
592 * started later after this function returns. The `start_state' is the
593 * state where the machine or thread is started. This function is used
594 * with both SilcFSM and SilcFSMThread contexts.
600 * fsm = silc_fsm_alloc(context, destructor, context, schedule);
601 * silc_fsm_start(fsm, first_state);
604 void silc_fsm_start(void *fsm, SilcFSMStateCallback start_state);
606 /****f* silcutil/SilcFSMAPI/silc_fsm_start_sync
610 * void silc_fsm_start_sync(void *fsm, SilcFSMStateCallback start_state);
614 * This function is same as silc_fsm_start, except that the FSM will
615 * be started immediately inside this function. After this function
616 * returns the `start_state' has already been executed. If the machine
617 * is completely synchronous (no waiting used in the machine) then
618 * the machine will have finished once this function returns. Also
619 * note that if the machine is completely synchronous the destructor
620 * will also be called from inside this function. This function is used
621 * with both SilcFSM and SilcFSMThread contexts.
624 void silc_fsm_start_sync(void *fsm, SilcFSMStateCallback start_state);
626 /****f* silcutil/SilcFSMAPI/silc_fsm_next
630 * void silc_fsm_next(void *fsm, SilcFSMStateCallback next_state);
634 * Set the next state to be executed. If the state function that
635 * call this function calls SILC_FSM_CONTINUE, the `next_state'
636 * will be executed immediately. If it calls SILC_FSM_YIELD it
637 * yields the thread and the `next_state' will be run after other
638 * threads have run first. This function must always be used to set
639 * the next state in the machine or thread. This function is used
640 * with both SilcFSM and SilcFSMThread contexts.
644 * // Move to next state
645 * silc_fsm_next(fsm, next_state);
649 void silc_fsm_next(void *fsm, SilcFSMStateCallback next_state);
651 /****f* silcutil/SilcFSMAPI/silc_fsm_next_later
655 * void silc_fsm_next_later(void *fsm, SilcFSMStateCallback next_state,
656 * SilcUInt32 seconds, SilcUInt32 useconds);
660 * Set the next state to be executed later, at the specified time.
661 * The SILC_FSM_WAIT must be called in the state function if this
662 * function is called. If any other state is returned machine operation
663 * is undefined. The machine or thread will move to `next_state' after
664 * the specified timeout. This function is used with both SilcFSM and
665 * SilcFSMThread contexts.
669 * If both `seconds' and `useconds' are 0, the effect is same as calling
670 * silc_fsm_next function, and SILC_FSM_CONTINUE must be called.
672 * If silc_fsm_continue or silc_fsm_continue_sync is called while the
673 * machine or thread is in SILC_FSM_WAIT state the timeout is automatically
674 * canceled and the state moves to the next state.
678 * // Move to next state after 10 seconds
679 * silc_fsm_next_later(fsm, next_state, 10, 0);
683 void silc_fsm_next_later(void *fsm, SilcFSMStateCallback next_state,
684 SilcUInt32 seconds, SilcUInt32 useconds);
686 /****f* silcutil/SilcFSMAPI/silc_fsm_continue
690 * void silc_fsm_continue(void *fsm);
694 * Continues in the state machine from a SILC_FSM_WAIT state. This can
695 * be called from outside waiting FSM to continue to the next state.
696 * This function can be used instead of SILC_FSM_CALL_CONTINUE macro
697 * in case the SILC_FSM_CALL was not used. This must not be used if
698 * SILC_FSM_CALL was used. This function is used with both SilcFSM and
699 * SilcFSMThread contexts.
702 void silc_fsm_continue(void *fsm);
704 /****f* silcutil/SilcFSMAPI/silc_fsm_continue_sync
708 * void silc_fsm_continue_sync(void *fsm);
712 * Continues immediately in the state machine from a SILC_FSM_WAIT state.
713 * This can be called from outside waiting FSM to immediately continue to
714 * the next state. This function can be used instead of the
715 * SILC_FSM_CALL_CONTINUE_SYNC macro in case the SILC_FSM_CALL was not used.
716 * This must not be used if SILC_FSM_CALL was used. This function is used
717 * with both SilcFSM and SilcFSMThread contexts.
720 void silc_fsm_continue_sync(void *fsm);
722 /****f* silcutil/SilcFSMAPI/silc_fsm_finish
726 * void silc_fsm_finish(void *fsm);
730 * Finishes the `fsm'. This function may be used in case the FSM
731 * needs to be finished outside FSM states. Usually FSM is finished
732 * by calling SILC_FSM_FINISH from the state, but if this is not
733 * possible this function may be called. This function is used with
734 * both SilcFSM and SilcFSMThread contexts.
736 * If the `fsm' is a machine and it has running threads, the machine
737 * will fatally fail. The caller must first finish the threads and
741 void silc_fsm_finish(void *fsm);
743 /****f* silcutil/SilcFSMAPI/silc_fsm_set_context
747 * void silc_fsm_set_context(void *fsm, void *fsm_context);
751 * Set new context for the `fsm'. This function can be used to change
752 * the context inside the `fsm', if needed. This function is used with
753 * both SilcFSM and SilcFSMThread contexts. The context is the
754 * `fsm_context' in the state function (SILC_FSM_STATE).
757 void silc_fsm_set_context(void *fsm, void *fsm_context);
759 /****f* silcutil/SilcFSMAPI/silc_fsm_get_context
763 * void *silc_fsm_get_context(void *fsm);
767 * Returns the context associated with the `fsm'. It is the context that
768 * was given to silc_fsm_alloc, silc_fsm_init, silc_fsm_thread_alloc or
769 * silc_fsm_thread_init. This function is used with both SilcFSM and
770 * SilcFSMThread contexts.
773 void *silc_fsm_get_context(void *fsm);
775 /****f* silcutil/SilcFSMAPI/silc_fsm_set_state_context
779 * void silc_fsm_set_state_context(void *fsm, void *state_context);
783 * Set's a state specific context for the `fsm'. This function can be
784 * used to change the state context inside the `fsm', if needed. This
785 * function is used with both SilcFSM and SilcFSMThread contexts. The
786 * context is the `state_context' in the state function (SILC_FSM_STATE).
789 void silc_fsm_set_state_context(void *fsm, void *state_context);
791 /****f* silcutil/SilcFSMAPI/silc_fsm_get_state_context
795 * void *silc_fsm_get_state_context(void *fsm);
799 * Returns the state context associated with the `fsm'. It is the context
800 * that was set with silc_fsm_set_state_context function. This function
801 * is used with both SilcFSM and SilcFSMThread contexts.
804 void *silc_fsm_get_state_context(void *fsm);
806 /****f* silcutil/SilcFSMAPI/silc_fsm_get_schedule
810 * SilcSchedule silc_fsm_get_schedule(void *fsm);
814 * Returns the SilcSchedule that has been associated with the `fsm'.
815 * If caller needs scheduler it may retrieve it with this function. This
816 * function is used with both SilcFSM and SilcFSMThread contexts.
818 * If the `fsm' is thread and real system threads are being used, and this
819 * is called from the thread, it will return the SilcSchedule that was
820 * allocated by the FSM for the thread. It is strongly recommended to
821 * use this SilcSchedule if you are using real threads, and you need
822 * scheduler in the thread. Note that, once the thread finishes the
823 * returned SilcSchedule becomes invalid.
825 * In other times this returns the SilcSchedule pointer that was given
826 * to silc_fsm_alloc or silc_fsm_init.
829 SilcSchedule silc_fsm_get_schedule(void *fsm);
831 /****f* silcutil/SilcFSMAPI/silc_fsm_get_machine
835 * SilcFSM silc_fsm_get_machine(SilcFSMThread thread);
839 * Returns the machine from the FSM thread indicated by `thread'.
842 SilcFSM silc_fsm_get_machine(SilcFSMThread thread);
844 /****f* silcutil/SilcFSMAPI/silc_fsm_is_started
848 * SilcBool silc_fsm_is_started(void *fsm);
852 * Returns TRUE if the machine or thread `fsm' has been started and has
853 * not been finished yet. This function is used with both SilcFSM and
854 * SilcFSMThread contexts.
857 SilcBool silc_fsm_is_started(void *fsm);
861 /****s* silcutil/SilcFSMAPI/SilcFSMEvent
865 * typedef struct SilcFSMEventObject *SilcFSMEvent;
869 * The FSM event context allocated with silc_fsm_event_alloc. The
870 * caller must free it with silc_fsm_event_free. It is also possible
871 * to use pre-allocated SilcFSMEventStruct instead of SilcFSMEvent context.
874 typedef struct SilcFSMEventObject *SilcFSMEvent;
876 /****s* silcutil/SilcFSMAPI/SilcFSMEventStruct
880 * typedef struct SilcFSMEventObject SilcFSMEventStruct;
884 * The FSM event context that can be used as pre-allocated context.
885 * It is initialized with silc_fsm_event_init. It need not be
889 typedef struct SilcFSMEventObject SilcFSMEventStruct;
891 /****f* silcutil/SilcFSMAPI/silc_fsm_event_alloc
895 * SilcFSMEvent silc_fsm_event_alloc(SilcFSM fsm);
899 * Allocates asynchronous FSM event. FSM events are asynchronous events
900 * that can be waited and signalled. They can be used as condition
901 * variables and signallers. They can be used for example to wait that
902 * some event happens, some thread moves to a specific state or similar.
903 * The FSM Events may also be used in FSM threads that are executed in
904 * real system threads. It is safe to wait and signal the event from
907 * Use the macros SILC_FSM_EVENT_WAIT and SILC_FSM_EVENT_TIMEDWAIT to wait
908 * for the event. Use the SILC_FSM_EVENT_SIGNAL macro to signal all the
912 SilcFSMEvent silc_fsm_event_alloc(SilcFSM fsm);
914 /****f* silcutil/SilcFSMAPI/silc_fsm_event_init
918 * void silc_fsm_event_init(SilcFSMEvent event, SilcFSM fsm);
922 * Initializes a pre-allocates FSM event context. This call is
923 * equivalent to silc_fsm_event_alloc except this use the pre-allocated
924 * context. This fuction does not allocate any memory.
927 void silc_fsm_event_init(SilcFSMEvent event, SilcFSM fsm);
929 /****f* silcutil/SilcFSMAPI/silc_fsm_event_free
933 * void silc_fsm_event_free(SilcFSMEvent event);
937 * Free the event allocated by silc_fsm_event_alloc function.
940 void silc_fsm_event_free(SilcFSMEvent event);
942 /****d* silcutil/SilcFSMAPI/SILC_FSM_EVENT_WAIT
946 * SILC_FSM_EVENT_WAIT(event)
950 * Macro used to wait for the `event' to be signalled. The machine
951 * or thread will be suspended while it is waiting for the event.
952 * This macro can only be used in FSM state functions. When the
953 * event is signalled the FSM will re-enter the current state (or
954 * state that was set with silc_fsm_next before waiting).
958 * // Signalling example
959 * ctx->async_event = silc_fsm_event_alloc(fsm);
962 * SILC_FSM_STATE(silc_foo_state)
966 * // Wait here for async call to complete
967 * SILC_FSM_EVENT_WAIT(ctx->async_event);
969 * // Async call completed
970 * if (ctx->async_success == FALSE)
976 #define SILC_FSM_EVENT_WAIT(event) \
978 if (silc_fsm_event_wait(event, fsm) == 0) \
982 /****d* silcutil/SilcFSMAPI/SILC_FSM_EVENT_TIMEDWAIT
986 * SILC_FSM_EVENT_TIMEDWAIT(event, seconds, useconds, timedout)
990 * Macro used to wait for the `event' to be signalled, or until
991 * the timeout specified by `seconds' and `useconds' has elapsed. If
992 * the timeout occurs before the event is signalled, the machine
993 * will wakeup. The `timedout' is SilcBool pointer and if it is
994 * non-NULL indication of whether timeout occurred or not is saved to
995 * the pointer. This macro can only be used in FSM state functions.
996 * When the event is signalled or timedout the FSM will re-enter
997 * the current state (or state that was set with silc_fsm_next before
1002 * SILC_FSM_STATE(silc_foo_state)
1004 * SilcBool timedout;
1007 * // Wait here for async call to complete, or 10 seconds for timeout
1008 * SILC_FSM_EVENT_TIMEDWAIT(ctx->async_event, 10, 0, &timedout);
1010 * // See if timeout occurred
1011 * if (timedout == TRUE)
1014 * // Async call completed
1015 * if (ctx->async_success == FALSE)
1021 #define SILC_FSM_EVENT_TIMEDWAIT(event, seconds, useconds, ret_to) \
1023 if (silc_fsm_event_timedwait(event, fsm, seconds, useconds, ret_to) == 0) \
1027 /****f* silcutil/SilcFSMAPI/SILC_FSM_EVENT_SIGNAL
1031 * SILC_FSM_EVENT_SIGNAL(event)
1035 * Signals the `event' and awakens everybody that are waiting for this
1036 * event. This macro never blocks. It can be safely called at any place
1037 * in state function and in asynchronous callbacks or other functions.
1041 * SILC_FSM_STATE(silc_foo_async_completion)
1045 * // Notify all waiters
1046 * ctx->async_success = TRUE;
1047 * SILC_FSM_EVENT_SIGNAL(ctx->async_event);
1052 #define SILC_FSM_EVENT_SIGNAL(event) \
1054 silc_fsm_event_signal(event); \
1057 #include "silcfsm_i.h"
1059 #endif /* SILCFSM_H */