1 /* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002, 2003 Free Software Foundation, Inc.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2, or (at your option)
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this software; see the file COPYING. If not, write to
15 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
16 * Boston, MA 02111-1307 USA
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
21 * The exception is that, if you link the GUILE library with other files
22 * to produce an executable, this does not by itself cause the
23 * resulting executable to be covered by the GNU General Public License.
24 * Your use of that executable is in no way restricted on account of
25 * linking the GUILE library code into it.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
30 * This exception applies only to the code released by the
31 * Free Software Foundation under the name GUILE. If you copy
32 * code from other Free Software Foundation releases into a copy of
33 * GUILE, as the General Public License permits, the exception does
34 * not apply to the code that you add in this way. To avoid misleading
35 * anyone as to the status of such modified files, you must delete
36 * this exception notice from them.
38 * If you write modifications of your own for GUILE, it is your choice
39 * whether to permit this exception to apply to your modifications.
40 * If you do not wish that, delete this exception notice. */
45 /* This file implements nice Scheme level threads on top of the gastly
54 #include "libguile/_scm.h"
55 #include "libguile/validate.h"
56 #include "libguile/root.h"
57 #include "libguile/eval.h"
58 #include "libguile/async.h"
59 #include "libguile/ports.h"
60 #include "libguile/threads.h"
61 #include "libguile/dynwind.h"
62 #include "libguile/iselect.h"
69 return scm_cons (SCM_EOL
, SCM_EOL
);
73 enqueue (SCM q
, SCM t
)
75 SCM c
= scm_cons (t
, SCM_EOL
);
76 if (SCM_NULLP (SCM_CDR (q
)))
79 SCM_SETCDR (SCM_CAR (q
), c
);
85 remqueue (SCM q
, SCM c
)
88 for (p
= SCM_CDR (q
); !SCM_NULLP (p
); p
= SCM_CDR (p
))
92 if (SCM_EQ_P (c
, SCM_CAR (q
)))
93 SCM_SETCAR (q
, SCM_CDR (c
));
94 SCM_SETCDR (prev
, SCM_CDR (c
));
110 SCM_SETCDR (q
, SCM_CDR (c
));
111 if (SCM_NULLP (SCM_CDR (q
)))
112 SCM_SETCAR (q
, SCM_EOL
);
119 #define THREAD_INITIALIZED_P(t) (t->base != NULL)
125 scm_t_cond sleep_cond
;
126 struct scm_thread
*next_waiting
;
128 /* This mutex represents this threads right to access the heap.
129 That right can temporarily be taken away by the GC. */
130 scm_t_mutex heap_mutex
;
131 int clear_freelists_p
; /* set if GC was done while thread was asleep */
133 scm_root_state
*root
;
139 /* For keeping track of the stack and registers. */
147 make_thread (SCM creation_protects
)
151 z
= scm_make_smob (scm_tc16_thread
);
152 t
= SCM_THREAD_DATA (z
);
154 t
->result
= creation_protects
;
156 scm_i_plugin_cond_init (&t
->sleep_cond
, 0);
157 scm_i_plugin_mutex_init (&t
->heap_mutex
, &scm_i_plugin_mutex
);
158 t
->clear_freelists_p
= 0;
164 init_thread_creatant (SCM thread
,
167 scm_thread
*t
= SCM_THREAD_DATA (thread
);
168 t
->thread
= scm_thread_self ();
174 thread_mark (SCM obj
)
176 scm_thread
*t
= SCM_THREAD_DATA (obj
);
177 scm_gc_mark (t
->result
);
178 return t
->root
->handle
; /* mark root-state of this thread */
182 thread_print (SCM exp
, SCM port
, scm_print_state
*pstate SCM_UNUSED
)
184 scm_thread
*t
= SCM_THREAD_DATA (exp
);
185 scm_puts ("#<thread ", port
);
186 scm_intprint ((unsigned long)t
->thread
, 10, port
);
187 scm_puts (" (", port
);
188 scm_intprint ((unsigned long)t
, 16, port
);
189 scm_puts (")>", port
);
194 thread_free (SCM obj
)
196 scm_thread
*t
= SCM_THREAD_DATA (obj
);
199 scm_gc_free (t
, sizeof (*t
), "thread");
205 #define cur_thread (SCM_CURRENT_THREAD->handle)
206 scm_t_key scm_i_thread_key
;
207 scm_t_key scm_i_root_state_key
;
210 scm_i_set_thread_data (void *data
)
212 scm_thread
*t
= SCM_CURRENT_THREAD
;
213 scm_setspecific (scm_i_root_state_key
, data
);
214 t
->root
= (scm_root_state
*)data
;
218 resume (scm_thread
*t
)
221 if (t
->clear_freelists_p
)
223 *SCM_FREELIST_LOC (scm_i_freelist
) = SCM_EOL
;
224 *SCM_FREELIST_LOC (scm_i_freelist2
) = SCM_EOL
;
225 t
->clear_freelists_p
= 0;
230 scm_i_enter_guile (scm_thread
*t
)
232 scm_i_plugin_mutex_lock (&t
->heap_mutex
);
239 scm_thread
*c
= SCM_CURRENT_THREAD
;
241 /* record top of stack for the GC */
242 c
->top
= (SCM_STACKITEM
*)&c
;
243 /* save registers. */
244 SCM_FLUSH_REGISTER_WINDOWS
;
253 scm_thread
*t
= suspend ();
254 scm_i_plugin_mutex_unlock (&t
->heap_mutex
);
258 /* Put the current thread to sleep until it is explicitely unblocked.
264 scm_thread
*t
= suspend ();
265 err
= scm_i_plugin_cond_wait (&t
->sleep_cond
, &t
->heap_mutex
);
270 /* Put the current thread to sleep until it is explicitely unblocked
271 or until a signal arrives or until time AT (absolute time) is
272 reached. Return 0 when it has been unblocked; errno otherwise.
275 timed_block (const struct timespec
*at
)
278 scm_thread
*t
= suspend ();
279 err
= scm_i_plugin_cond_timedwait (&t
->sleep_cond
, &t
->heap_mutex
, at
);
284 /* Unblock a sleeping thread.
287 unblock (scm_thread
*t
)
289 scm_i_plugin_cond_signal (&t
->sleep_cond
);
292 /*** Thread creation */
294 static scm_t_mutex thread_admin_mutex
;
295 static SCM all_threads
;
296 static int thread_count
;
298 typedef struct launch_data
{
301 scm_t_catch_body body
;
303 scm_t_catch_handler handler
;
308 body_bootstrip (launch_data
* data
)
310 /* First save the new root continuation */
311 data
->rootcont
= scm_root
->rootcont
;
312 return (data
->body
) (data
->body_data
);
316 handler_bootstrip (launch_data
* data
, SCM tag
, SCM throw_args
)
318 scm_root
->rootcont
= data
->rootcont
;
319 return (data
->handler
) (data
->handler_data
, tag
, throw_args
);
323 really_launch (SCM_STACKITEM
*base
, launch_data
*data
)
327 thread
= data
->thread
;
328 t
= SCM_THREAD_DATA (thread
);
329 SCM_FREELIST_CREATE (scm_i_freelist
);
330 SCM_FREELIST_CREATE (scm_i_freelist2
);
331 scm_setspecific (scm_i_thread_key
, t
);
332 scm_setspecific (scm_i_root_state_key
, t
->root
);
333 scm_i_plugin_mutex_lock (&t
->heap_mutex
); /* ensure that we "own" the heap */
334 init_thread_creatant (thread
, base
); /* must own the heap */
336 data
->rootcont
= SCM_BOOL_F
;
338 scm_internal_cwdr ((scm_t_catch_body
) body_bootstrip
,
340 (scm_t_catch_handler
) handler_bootstrip
,
342 scm_i_leave_guile (); /* release the heap */
345 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
346 all_threads
= scm_delq_x (thread
, all_threads
);
349 /* detach before unlocking in order to not become joined when detached */
350 scm_thread_detach (t
->thread
);
351 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
355 launch_thread (void *p
)
357 really_launch ((SCM_STACKITEM
*)&p
, (launch_data
*)p
);
362 create_thread (scm_t_catch_body body
, void *body_data
,
363 scm_t_catch_handler handler
, void *handler_data
,
368 /* Make new thread. The first thing the new thread will do is to
369 lock guile_mutex. Thus, we can safely complete its
370 initialization after creating it. While the new thread starts,
371 all its data is protected via all_threads.
381 /* Allocate thread locals. */
382 root
= scm_make_root (scm_root
->handle
);
383 data
= scm_malloc (sizeof (launch_data
));
386 thread
= make_thread (protects
);
387 data
->thread
= thread
;
389 data
->body_data
= body_data
;
390 data
->handler
= handler
;
391 data
->handler_data
= handler_data
;
392 t
= SCM_THREAD_DATA (thread
);
393 /* must initialize root state pointer before the thread is linked
395 t
->root
= SCM_ROOT_STATE (root
);
396 /* disconnect from parent, to prevent remembering dead threads */
397 t
->root
->parent
= SCM_BOOL_F
;
398 /* start with an empty dynwind chain */
399 t
->root
->dynwinds
= SCM_EOL
;
401 /* In order to avoid the need of synchronization between parent
402 and child thread, we need to insert the child into all_threads
405 SCM new_threads
= scm_cons (thread
, SCM_BOOL_F
); /* could cause GC */
406 scm_thread
*parent
= scm_i_leave_guile (); /* to prevent deadlock */
407 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
408 SCM_SETCDR (new_threads
, all_threads
);
409 all_threads
= new_threads
;
411 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
413 scm_remember_upto_here_1 (root
);
415 scm_i_enter_guile (parent
);
418 err
= scm_i_plugin_thread_create (&th
, 0, launch_thread
, (void *) data
);
421 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
422 all_threads
= scm_delq_x (thread
, all_threads
);
423 ((scm_thread
*) SCM_THREAD_DATA(thread
))->exited
= 1;
425 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
431 scm_syserror ("create-thread");
438 SCM_DEFINE (scm_call_with_new_thread
, "call-with-new-thread", 2, 0, 0,
439 (SCM thunk
, SCM handler
),
440 "Evaluate @var{(thunk)} in a new thread, and new dynamic context, "
441 "returning a new thread object representing the thread. "
442 "If an error occurs during evaluation, call error-thunk, passing it an "
443 "error code describing the condition. "
444 "If this happens, the error-thunk is called outside the scope of the new "
445 "root -- it is called in the same dynamic context in which "
446 "with-new-thread was evaluated, but not in the callers thread. "
447 "All the evaluation rules for dynamic roots apply to threads.")
448 #define FUNC_NAME s_scm_call_with_new_thread
450 SCM_ASSERT (SCM_NFALSEP (scm_thunk_p (thunk
)), thunk
, SCM_ARG1
, FUNC_NAME
);
451 SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (handler
)), handler
, SCM_ARG2
,
454 return create_thread ((scm_t_catch_body
) scm_call_0
, thunk
,
455 (scm_t_catch_handler
) scm_apply_1
, handler
,
456 scm_cons (thunk
, handler
));
460 SCM_DEFINE (scm_yield
, "yield", 0, 0, 0,
462 "Move the calling thread to the end of the scheduling queue.")
463 #define FUNC_NAME s_scm_yield
465 return SCM_BOOL (scm_thread_yield
);
469 SCM_DEFINE (scm_join_thread
, "join-thread", 1, 0, 0,
471 "Suspend execution of the calling thread until the target @var{thread} "
472 "terminates, unless the target @var{thread} has already terminated. ")
473 #define FUNC_NAME s_scm_join_thread
478 SCM_VALIDATE_THREAD (1, thread
);
479 if (SCM_EQ_P (cur_thread
, thread
))
480 SCM_MISC_ERROR ("can not join the current thread", SCM_EOL
);
482 t
= SCM_THREAD_DATA (thread
);
486 c
= scm_i_leave_guile ();
487 while (!THREAD_INITIALIZED_P (t
))
488 scm_i_plugin_thread_yield ();
489 scm_thread_join (t
->thread
, 0);
490 scm_i_enter_guile (c
);
493 t
->result
= SCM_BOOL_F
;
498 SCM
*scm_loc_sys_thread_handler
;
501 scm_i_make_future (SCM thunk
)
503 SCM_RETURN_NEWSMOB2 (scm_tc16_future
,
504 create_thread ((scm_t_catch_body
) scm_call_0
,
506 (scm_t_catch_handler
) scm_apply_1
,
507 *scm_loc_sys_thread_handler
,
509 *scm_loc_sys_thread_handler
)),
510 scm_make_rec_mutex ());
514 future_free (SCM future
)
516 scm_rec_mutex_free (SCM_FUTURE_MUTEX (future
));
521 future_print (SCM exp
, SCM port
, scm_print_state
*pstate
)
523 int writingp
= SCM_WRITINGP (pstate
);
524 scm_puts ("#<future ", port
);
525 SCM_SET_WRITINGP (pstate
, 1);
526 scm_iprin1 (SCM_FUTURE_DATA (exp
), port
, pstate
);
527 SCM_SET_WRITINGP (pstate
, writingp
);
528 scm_putc ('>', port
);
532 SCM_DEFINE (scm_future_ref
, "future-ref", 1, 0, 0,
534 "If the future @var{x} has not been computed yet, compute and\n"
535 "return @var{x}, otherwise just return the previously computed\n"
537 #define FUNC_NAME s_scm_future_ref
539 SCM_VALIDATE_FUTURE (1, future
);
540 scm_rec_mutex_lock (SCM_FUTURE_MUTEX (future
));
541 if (!SCM_FUTURE_COMPUTED_P (future
))
543 SCM value
= scm_join_thread (SCM_FUTURE_DATA (future
));
544 if (!SCM_FUTURE_COMPUTED_P (future
))
546 SCM_SET_FUTURE_DATA (future
, value
);
547 SCM_SET_FUTURE_COMPUTED (future
);
550 scm_rec_mutex_unlock (SCM_FUTURE_MUTEX (future
));
551 return SCM_FUTURE_DATA (future
);
557 /* We implement our own mutex type since we want them to be 'fair', we
558 want to do fancy things while waiting for them (like running
559 asyncs) and we want to support waiting on many things at once.
560 Also, we might add things that are nice for debugging.
563 typedef struct fair_mutex
{
564 /* the thread currently owning the mutex, or SCM_BOOL_F. */
568 /* how much the owner owns us. */
570 /* the threads waiting for this mutex. */
575 fair_mutex_mark (SCM mx
)
577 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
578 scm_gc_mark (m
->owner
);
582 SCM_DEFINE (scm_make_fair_mutex
, "make-fair-mutex", 0, 0, 0,
584 "Create a new fair mutex object. ")
585 #define FUNC_NAME s_scm_make_fair_mutex
587 SCM mx
= scm_make_smob (scm_tc16_fair_mutex
);
588 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
589 scm_i_plugin_mutex_init (&m
->lock
, &scm_i_plugin_mutex
);
591 m
->owner
= SCM_BOOL_F
;
593 m
->waiting
= make_queue ();
599 fair_mutex_lock (fair_mutex
*m
)
601 scm_i_plugin_mutex_lock (&m
->lock
);
603 /* Need to wait if another thread is just temporarily unlocking.
604 This is happens very seldom and only when the other thread is
605 between scm_mutex_unlock and scm_i_plugin_mutex_lock below. */
611 if (m
->owner
== SCM_BOOL_F
)
612 m
->owner
= cur_thread
;
613 else if (m
->owner
== cur_thread
)
619 SCM c
= enqueue (m
->waiting
, cur_thread
);
621 /* Note: It's important that m->lock is never locked for
622 any longer amount of time since that could prevent GC */
623 scm_i_plugin_mutex_unlock (&m
->lock
);
625 if (m
->owner
== cur_thread
)
627 scm_i_plugin_mutex_lock (&m
->lock
);
628 remqueue (m
->waiting
, c
);
629 scm_i_plugin_mutex_unlock (&m
->lock
);
633 scm_i_plugin_mutex_lock (&m
->lock
);
636 scm_i_plugin_mutex_unlock (&m
->lock
);
641 fair_mutex_trylock (fair_mutex
*m
)
643 scm_i_plugin_mutex_lock (&m
->lock
);
644 if (m
->owner
== SCM_BOOL_F
)
645 m
->owner
= cur_thread
;
646 else if (m
->owner
== cur_thread
)
650 scm_i_plugin_mutex_unlock (&m
->lock
);
653 scm_i_plugin_mutex_unlock (&m
->lock
);
658 fair_mutex_unlock (fair_mutex
*m
)
660 scm_i_plugin_mutex_lock (&m
->lock
);
661 if (m
->owner
!= cur_thread
)
663 scm_i_plugin_mutex_unlock (&m
->lock
);
666 else if (m
->level
> 0)
670 SCM next
= dequeue (m
->waiting
);
671 if (!SCM_FALSEP (next
))
674 unblock (SCM_THREAD_DATA (next
));
677 m
->owner
= SCM_BOOL_F
;
679 scm_i_plugin_mutex_unlock (&m
->lock
);
683 /*** Fair condition variables */
685 /* Like mutexes, we implement our own condition variables using the
689 typedef struct fair_cond
{
691 /* the threads waiting for this condition. */
696 fair_cond_mark (SCM cv
)
698 fair_cond
*c
= SCM_CONDVAR_DATA (cv
);
702 SCM_DEFINE (scm_make_fair_condition_variable
, "make-fair-condition-variable", 0, 0, 0,
704 "Make a new fair condition variable.")
705 #define FUNC_NAME s_scm_make_fair_condition_variable
707 SCM cv
= scm_make_smob (scm_tc16_fair_condvar
);
708 fair_cond
*c
= SCM_CONDVAR_DATA (cv
);
709 scm_i_plugin_mutex_init (&c
->lock
, 0);
710 c
->waiting
= make_queue ();
716 fair_cond_timedwait (fair_cond
*c
,
718 const struct timespec
*waittime
)
721 scm_i_plugin_mutex_lock (&c
->lock
);
725 enqueue (c
->waiting
, cur_thread
);
726 scm_i_plugin_mutex_unlock (&c
->lock
);
727 fair_mutex_unlock (m
); /*fixme* - not thread safe */
728 if (waittime
== NULL
)
731 err
= timed_block (waittime
);
735 /* XXX - check whether we have been signalled. */
742 fair_cond_signal (fair_cond
*c
)
745 scm_i_plugin_mutex_lock (&c
->lock
);
746 if (!SCM_FALSEP (th
= dequeue (c
->waiting
)))
747 unblock (SCM_THREAD_DATA (th
));
748 scm_i_plugin_mutex_unlock (&c
->lock
);
753 fair_cond_broadcast (fair_cond
*c
)
756 scm_i_plugin_mutex_lock (&c
->lock
);
757 while (!SCM_FALSEP (th
= dequeue (c
->waiting
)))
758 unblock (SCM_THREAD_DATA (th
));
759 scm_i_plugin_mutex_unlock (&c
->lock
);
765 SCM_DEFINE (scm_make_mutex
, "make-mutex", 0, 0, 0,
767 "Create a new mutex object. ")
768 #define FUNC_NAME s_scm_make_mutex
770 SCM mx
= scm_make_smob (scm_tc16_mutex
);
771 scm_i_plugin_mutex_init (SCM_MUTEX_DATA (mx
), &scm_i_plugin_mutex
);
776 /*fixme* change documentation */
777 SCM_DEFINE (scm_lock_mutex
, "lock-mutex", 1, 0, 0,
779 "Lock @var{mutex}. If the mutex is already locked, the calling thread "
780 "blocks until the mutex becomes available. The function returns when "
781 "the calling thread owns the lock on @var{mutex}. Locking a mutex that "
782 "a thread already owns will succeed right away and will not block the "
783 "thread. That is, Guile's mutexes are @emph{recursive}. ")
784 #define FUNC_NAME s_scm_lock_mutex
787 SCM_VALIDATE_MUTEX (1, mx
);
789 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
790 err
= fair_mutex_lock (SCM_MUTEX_DATA (mx
));
793 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
794 err
= scm_mutex_lock (m
);
806 SCM_DEFINE (scm_try_mutex
, "try-mutex", 1, 0, 0,
808 "Try to lock @var{mutex}. If the mutex is already locked by someone "
809 "else, return @code{#f}. Else lock the mutex and return @code{#t}. ")
810 #define FUNC_NAME s_scm_try_mutex
813 SCM_VALIDATE_MUTEX (1, mx
);
815 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
816 err
= fair_mutex_trylock (SCM_MUTEX_DATA (mx
));
819 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
820 err
= scm_mutex_trylock (m
);
836 SCM_DEFINE (scm_unlock_mutex
, "unlock-mutex", 1, 0, 0,
838 "Unlocks @var{mutex} if the calling thread owns the lock on "
839 "@var{mutex}. Calling unlock-mutex on a mutex not owned by the current "
840 "thread results in undefined behaviour. Once a mutex has been unlocked, "
841 "one thread blocked on @var{mutex} is awakened and grabs the mutex "
842 "lock. Every call to @code{lock-mutex} by this thread must be matched "
843 "with a call to @code{unlock-mutex}. Only the last call to "
844 "@code{unlock-mutex} will actually unlock the mutex. ")
845 #define FUNC_NAME s_scm_unlock_mutex
848 SCM_VALIDATE_MUTEX (1, mx
);
850 if (SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)
852 err
= fair_mutex_unlock (SCM_MUTEX_DATA (mx
));
855 fair_mutex
*m
= SCM_MUTEX_DATA (mx
);
856 if (m
->owner
!= cur_thread
)
858 if (m
->owner
== SCM_BOOL_F
)
859 SCM_MISC_ERROR ("mutex not locked", SCM_EOL
);
861 SCM_MISC_ERROR ("mutex not locked by this thread", SCM_EOL
);
867 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
868 err
= scm_mutex_unlock (m
);
880 /*** Condition variables */
882 SCM_DEFINE (scm_make_condition_variable
, "make-condition-variable", 0, 0, 0,
884 "Make a new condition variable.")
885 #define FUNC_NAME s_scm_make_condition_variable
887 SCM cv
= scm_make_smob (scm_tc16_condvar
);
888 scm_i_plugin_cond_init (SCM_CONDVAR_DATA (cv
), 0);
893 SCM_DEFINE (scm_timed_wait_condition_variable
, "wait-condition-variable", 2, 1, 0,
894 (SCM cv
, SCM mx
, SCM t
),
895 "Wait until @var{cond-var} has been signalled. While waiting, "
896 "@var{mutex} is atomically unlocked (as with @code{unlock-mutex}) and "
897 "is locked again when this function returns. When @var{time} is given, "
898 "it specifies a point in time where the waiting should be aborted. It "
899 "can be either a integer as returned by @code{current-time} or a pair "
900 "as returned by @code{gettimeofday}. When the waiting is aborted the "
901 "mutex is locked and @code{#f} is returned. When the condition "
902 "variable is in fact signalled, the mutex is also locked and @code{#t} "
904 #define FUNC_NAME s_scm_timed_wait_condition_variable
906 struct timespec waittime
;
909 SCM_VALIDATE_CONDVAR (1, cv
);
910 SCM_VALIDATE_MUTEX (2, mx
);
911 if (!((SCM_TYP16 (cv
) == scm_tc16_condvar
912 && SCM_TYP16 (mx
) == scm_tc16_mutex
)
913 || (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
914 && SCM_TYP16 (mx
) == scm_tc16_fair_mutex
)))
915 SCM_MISC_ERROR ("Condition variable and mutex are of different kinds.",
922 SCM_VALIDATE_UINT_COPY (3, SCM_CAR (t
), waittime
.tv_sec
);
923 SCM_VALIDATE_UINT_COPY (3, SCM_CDR (t
), waittime
.tv_nsec
);
924 waittime
.tv_nsec
*= 1000;
928 SCM_VALIDATE_UINT_COPY (3, t
, waittime
.tv_sec
);
929 waittime
.tv_nsec
= 0;
933 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
934 err
= fair_cond_timedwait (SCM_CONDVAR_DATA (cv
),
936 SCM_UNBNDP (t
) ? NULL
: &waittime
);
939 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
940 scm_t_mutex
*m
= SCM_MUTEX_DATA (mx
);
942 err
= scm_cond_wait (c
, m
);
944 err
= scm_cond_timedwait (c
, m
, &waittime
);
949 if (err
== ETIMEDOUT
)
958 SCM_DEFINE (scm_signal_condition_variable
, "signal-condition-variable", 1, 0, 0,
960 "Wake up one thread that is waiting for @var{cv}")
961 #define FUNC_NAME s_scm_signal_condition_variable
963 SCM_VALIDATE_CONDVAR (1, cv
);
964 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
965 fair_cond_signal (SCM_CONDVAR_DATA (cv
));
968 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
975 SCM_DEFINE (scm_broadcast_condition_variable
, "broadcast-condition-variable", 1, 0, 0,
977 "Wake up all threads that are waiting for @var{cv}. ")
978 #define FUNC_NAME s_scm_broadcast_condition_variable
980 SCM_VALIDATE_CONDVAR (1, cv
);
981 if (SCM_TYP16 (cv
) == scm_tc16_fair_condvar
)
982 fair_cond_broadcast (SCM_CONDVAR_DATA (cv
));
985 scm_t_cond
*c
= SCM_CONDVAR_DATA (cv
);
986 scm_cond_broadcast (c
);
992 /*** Marking stacks */
994 /* XXX - what to do with this? Do we need to handle this for blocked
998 # define SCM_MARK_BACKING_STORE() do { \
1000 SCM_STACKITEM * top, * bot; \
1001 getcontext (&ctx); \
1002 scm_mark_locations ((SCM_STACKITEM *) &ctx.uc_mcontext, \
1003 ((size_t) (sizeof (SCM_STACKITEM) - 1 + sizeof ctx.uc_mcontext) \
1004 / sizeof (SCM_STACKITEM))); \
1005 bot = (SCM_STACKITEM *) __libc_ia64_register_backing_store_base; \
1006 top = (SCM_STACKITEM *) ctx.uc_mcontext.sc_ar_bsp; \
1007 scm_mark_locations (bot, top - bot); } while (0)
1009 # define SCM_MARK_BACKING_STORE()
1013 scm_threads_mark_stacks (void)
1016 for (c
= all_threads
; !SCM_NULLP (c
); c
= SCM_CDR (c
))
1018 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (c
));
1019 if (!THREAD_INITIALIZED_P (t
))
1021 /* Not fully initialized yet. */
1028 if (t
->thread
!= scm_thread_self ())
1032 /* stack_len is long rather than sizet in order to guarantee
1033 that &stack_len is long aligned */
1034 #ifdef STACK_GROWS_UP
1035 stack_len
= ((SCM_STACKITEM
*) (&t
) -
1036 (SCM_STACKITEM
*) thread
->base
);
1038 /* Protect from the C stack. This must be the first marking
1039 * done because it provides information about what objects
1040 * are "in-use" by the C code. "in-use" objects are those
1041 * for which the information about length and base address must
1042 * remain usable. This requirement is stricter than a liveness
1043 * requirement -- in particular, it constrains the implementation
1046 SCM_FLUSH_REGISTER_WINDOWS
;
1047 /* This assumes that all registers are saved into the jmp_buf */
1048 setjmp (scm_save_regs_gc_mark
);
1049 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
1050 ((size_t) sizeof scm_save_regs_gc_mark
1051 / sizeof (SCM_STACKITEM
)));
1053 scm_mark_locations (((size_t) t
->base
,
1054 (sizet
) stack_len
));
1056 stack_len
= ((SCM_STACKITEM
*) t
->base
-
1057 (SCM_STACKITEM
*) (&t
));
1059 /* Protect from the C stack. This must be the first marking
1060 * done because it provides information about what objects
1061 * are "in-use" by the C code. "in-use" objects are those
1062 * for which the information about length and base address must
1063 * remain usable. This requirement is stricter than a liveness
1064 * requirement -- in particular, it constrains the implementation
1067 SCM_FLUSH_REGISTER_WINDOWS
;
1068 /* This assumes that all registers are saved into the jmp_buf */
1069 setjmp (scm_save_regs_gc_mark
);
1070 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
1071 ((size_t) sizeof scm_save_regs_gc_mark
1072 / sizeof (SCM_STACKITEM
)));
1074 scm_mark_locations ((SCM_STACKITEM
*) &t
,
1080 /* Suspended thread */
1081 #ifdef STACK_GROWS_UP
1082 long stack_len
= t
->top
- t
->base
;
1083 scm_mark_locations (t
->base
, stack_len
);
1085 long stack_len
= t
->base
- t
->top
;
1086 scm_mark_locations (t
->top
, stack_len
);
1088 scm_mark_locations ((SCM_STACKITEM
*) t
->regs
,
1089 ((size_t) sizeof(t
->regs
)
1090 / sizeof (SCM_STACKITEM
)));
1098 scm_internal_select (int nfds
,
1099 SELECT_TYPE
*readfds
,
1100 SELECT_TYPE
*writefds
,
1101 SELECT_TYPE
*exceptfds
,
1102 struct timeval
*timeout
)
1105 scm_thread
*c
= scm_i_leave_guile ();
1106 res
= scm_i_plugin_select (nfds
, readfds
, writefds
, exceptfds
, timeout
);
1108 scm_i_enter_guile (c
);
1114 /* Low-level C API */
1117 scm_spawn_thread (scm_t_catch_body body
, void *body_data
,
1118 scm_t_catch_handler handler
, void *handler_data
)
1120 return create_thread (body
, body_data
, handler
, handler_data
, SCM_BOOL_F
);
1124 scm_mutex_lock (scm_t_mutex
*m
)
1126 scm_thread
*t
= scm_i_leave_guile ();
1127 int res
= scm_i_plugin_mutex_lock (m
);
1128 scm_i_enter_guile (t
);
1133 scm_make_rec_mutex ()
1135 scm_t_rec_mutex
*m
= scm_malloc (sizeof (scm_t_rec_mutex
));
1136 scm_i_plugin_rec_mutex_init (m
, &scm_i_plugin_rec_mutex
);
1141 scm_rec_mutex_free (scm_t_rec_mutex
*m
)
1143 scm_i_plugin_rec_mutex_destroy (m
);
1148 scm_rec_mutex_lock (scm_t_rec_mutex
*m
)
1150 scm_thread
*t
= scm_i_leave_guile ();
1151 int res
= scm_i_plugin_rec_mutex_lock (m
);
1152 scm_i_enter_guile (t
);
1157 scm_cond_wait (scm_t_cond
*c
, scm_t_mutex
*m
)
1159 scm_thread
*t
= scm_i_leave_guile ();
1160 scm_i_plugin_cond_wait (c
, m
);
1161 scm_i_enter_guile (t
);
1166 scm_cond_timedwait (scm_t_cond
*c
, scm_t_mutex
*m
, const struct timespec
*wt
)
1168 scm_thread
*t
= scm_i_leave_guile ();
1169 int res
= scm_i_plugin_cond_timedwait (c
, m
, wt
);
1170 scm_i_enter_guile (t
);
1177 scm_i_enter_guile (SCM_CURRENT_THREAD
);
1183 scm_i_leave_guile ();
1187 scm_thread_usleep (unsigned long usecs
)
1190 tv
.tv_usec
= usecs
% 1000000;
1191 tv
.tv_sec
= usecs
/ 1000000;
1192 scm_internal_select (0, NULL
, NULL
, NULL
, &tv
);
1193 return tv
.tv_usec
+ tv
.tv_sec
*1000000;
1197 scm_thread_sleep (unsigned long secs
)
1202 scm_internal_select (0, NULL
, NULL
, NULL
, &tv
);
1208 SCM_DEFINE (scm_current_thread
, "current-thread", 0, 0, 0,
1210 "Return the thread that called this function.")
1211 #define FUNC_NAME s_scm_current_thread
1217 SCM_DEFINE (scm_all_threads
, "all-threads", 0, 0, 0,
1219 "Return a list of all threads.")
1220 #define FUNC_NAME s_scm_all_threads
1222 return scm_list_copy (all_threads
);
1227 scm_i_thread_root (SCM thread
)
1229 return ((scm_thread
*) SCM_THREAD_DATA (thread
))->root
;
1232 SCM_DEFINE (scm_thread_exited_p
, "thread-exited?", 1, 0, 0,
1234 "Return @code{#t} iff @var{thread} has exited.\n")
1235 #define FUNC_NAME s_scm_thread_exited_p
1237 return SCM_BOOL (scm_c_thread_exited_p (thread
));
1242 scm_c_thread_exited_p (SCM thread
)
1243 #define FUNC_NAME s_scm_thread_exited_p
1246 SCM_VALIDATE_THREAD (1, thread
);
1247 t
= SCM_THREAD_DATA (thread
);
1252 static scm_t_cond wake_up_cond
;
1253 int scm_i_thread_go_to_sleep
;
1254 static int gc_section_count
= 0;
1255 static int threads_initialized_p
= 0;
1258 scm_i_thread_put_to_sleep ()
1260 if (threads_initialized_p
&& !gc_section_count
++)
1263 scm_i_plugin_mutex_lock (&thread_admin_mutex
);
1264 threads
= all_threads
;
1265 /* Signal all threads to go to sleep */
1266 scm_i_thread_go_to_sleep
= 1;
1267 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1268 if (SCM_CAR (threads
) != cur_thread
)
1270 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1271 scm_i_plugin_mutex_lock (&t
->heap_mutex
);
1273 scm_i_thread_go_to_sleep
= 0;
1278 scm_i_thread_invalidate_freelists ()
1280 /* Don't need to lock thread_admin_mutex here since we are single threaded */
1281 SCM threads
= all_threads
;
1282 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1283 if (SCM_CAR (threads
) != cur_thread
)
1285 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1286 t
->clear_freelists_p
= 1;
1291 scm_i_thread_wake_up ()
1293 if (threads_initialized_p
&& !--gc_section_count
)
1296 threads
= all_threads
;
1297 scm_i_plugin_cond_broadcast (&wake_up_cond
);
1298 for (; !SCM_NULLP (threads
); threads
= SCM_CDR (threads
))
1299 if (SCM_CAR (threads
) != cur_thread
)
1301 scm_thread
*t
= SCM_THREAD_DATA (SCM_CAR (threads
));
1302 scm_i_plugin_mutex_unlock (&t
->heap_mutex
);
1304 scm_i_plugin_mutex_unlock (&thread_admin_mutex
);
1309 scm_i_thread_sleep_for_gc ()
1313 scm_i_plugin_cond_wait (&wake_up_cond
, &t
->heap_mutex
);
1317 scm_t_mutex scm_i_critical_section_mutex
;
1318 scm_t_rec_mutex scm_i_defer_mutex
;
1320 #ifdef USE_PTHREAD_THREADS
1321 #include "libguile/pthread-threads.c"
1323 #include "libguile/threads-plugin.c"
1325 /*** Initialization */
1328 scm_threads_prehistory ()
1331 #ifdef USE_PTHREAD_THREADS
1332 /* Must be called before any initialization of a mutex. */
1333 scm_init_pthread_threads ();
1335 scm_i_plugin_mutex_init (&thread_admin_mutex
, &scm_i_plugin_mutex
);
1336 scm_i_plugin_cond_init (&wake_up_cond
, 0);
1337 scm_i_plugin_mutex_init (&scm_i_critical_section_mutex
, &scm_i_plugin_mutex
);
1339 scm_i_plugin_key_create (&scm_i_thread_key
, 0);
1340 scm_i_plugin_key_create (&scm_i_root_state_key
, 0);
1341 scm_i_plugin_rec_mutex_init (&scm_i_defer_mutex
, &scm_i_plugin_rec_mutex
);
1342 /* Allocate a fake thread object to be used during bootup. */
1343 t
= malloc (sizeof (scm_thread
));
1345 t
->clear_freelists_p
= 0;
1346 scm_i_plugin_mutex_init (&t
->heap_mutex
, &scm_i_plugin_mutex
);
1347 scm_setspecific (scm_i_thread_key
, t
);
1348 scm_i_enter_guile (t
);
1351 scm_t_bits scm_tc16_thread
;
1352 scm_t_bits scm_tc16_future
;
1353 scm_t_bits scm_tc16_mutex
;
1354 scm_t_bits scm_tc16_fair_mutex
;
1355 scm_t_bits scm_tc16_condvar
;
1356 scm_t_bits scm_tc16_fair_condvar
;
1359 scm_init_threads (SCM_STACKITEM
*base
)
1362 scm_tc16_thread
= scm_make_smob_type ("thread", sizeof (scm_thread
));
1363 scm_tc16_mutex
= scm_make_smob_type ("mutex", sizeof (scm_t_mutex
));
1364 scm_tc16_fair_mutex
= scm_make_smob_type ("fair-mutex",
1365 sizeof (fair_mutex
));
1366 scm_tc16_condvar
= scm_make_smob_type ("condition-variable",
1367 sizeof (scm_t_cond
));
1368 scm_tc16_fair_condvar
= scm_make_smob_type ("fair-condition-variable",
1369 sizeof (fair_cond
));
1371 thread
= make_thread (SCM_BOOL_F
);
1372 /* Replace initial fake thread with a real thread object */
1373 free (SCM_CURRENT_THREAD
);
1374 scm_setspecific (scm_i_thread_key
, SCM_THREAD_DATA (thread
));
1375 scm_i_enter_guile (SCM_CURRENT_THREAD
);
1377 /* root is set later from init.c */
1378 init_thread_creatant (thread
, base
);
1380 scm_gc_register_root (&all_threads
);
1381 all_threads
= scm_cons (thread
, SCM_EOL
);
1383 scm_set_smob_mark (scm_tc16_thread
, thread_mark
);
1384 scm_set_smob_print (scm_tc16_thread
, thread_print
);
1385 scm_set_smob_free (scm_tc16_thread
, thread_free
);
1387 scm_set_smob_mark (scm_tc16_fair_mutex
, fair_mutex_mark
);
1389 scm_set_smob_mark (scm_tc16_fair_condvar
, fair_cond_mark
);
1391 scm_tc16_future
= scm_make_smob_type ("future", 0);
1392 scm_set_smob_mark (scm_tc16_future
, scm_markcdr
);
1393 scm_set_smob_free (scm_tc16_future
, future_free
);
1394 scm_set_smob_print (scm_tc16_future
, future_print
);
1396 threads_initialized_p
= 1;
1400 scm_init_thread_procs ()
1402 scm_loc_sys_thread_handler
1403 = SCM_VARIABLE_LOC (scm_c_define ("%thread-handler", SCM_BOOL_F
));
1404 #include "libguile/threads.x"