1 /* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
3 * This library is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU Lesser General Public
5 * License as published by the Free Software Foundation; either
6 * version 2.1 of the License, or (at your option) any later version.
8 * This library 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 GNU
11 * Lesser General Public License for more details.
13 * You should have received a copy of the GNU Lesser General Public
14 * License along with this library; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #include "libguile/_scm.h"
33 #include <string.h> /* for memset used by FD_ZERO on Solaris 10 */
40 #include "libguile/validate.h"
41 #include "libguile/root.h"
42 #include "libguile/eval.h"
43 #include "libguile/async.h"
44 #include "libguile/ports.h"
45 #include "libguile/threads.h"
46 #include "libguile/dynwind.h"
47 #include "libguile/iselect.h"
48 #include "libguile/fluids.h"
49 #include "libguile/continuations.h"
50 #include "libguile/gc.h"
51 #include "libguile/init.h"
52 #include "libguile/scmsigs.h"
53 #include "libguile/strings.h"
57 # define ETIMEDOUT WSAETIMEDOUT
61 # define pipe(fd) _pipe (fd, 256, O_BINARY)
62 #endif /* __MINGW32__ */
64 #include <full-read.h>
68 to_timespec (SCM t
, scm_t_timespec
*waittime
)
72 waittime
->tv_sec
= scm_to_ulong (SCM_CAR (t
));
73 waittime
->tv_nsec
= scm_to_ulong (SCM_CDR (t
)) * 1000;
77 double time
= scm_to_double (t
);
78 double sec
= scm_c_truncate (time
);
80 waittime
->tv_sec
= (long) sec
;
81 waittime
->tv_nsec
= (long) ((time
- sec
) * 1000000000);
87 /* Make an empty queue data structure.
92 return scm_cons (SCM_EOL
, SCM_EOL
);
95 /* Put T at the back of Q and return a handle that can be used with
96 remqueue to remove T from Q again.
99 enqueue (SCM q
, SCM t
)
101 SCM c
= scm_cons (t
, SCM_EOL
);
102 SCM_CRITICAL_SECTION_START
;
103 if (scm_is_null (SCM_CDR (q
)))
106 SCM_SETCDR (SCM_CAR (q
), c
);
108 SCM_CRITICAL_SECTION_END
;
112 /* Remove the element that the handle C refers to from the queue Q. C
113 must have been returned from a call to enqueue. The return value
114 is zero when the element referred to by C has already been removed.
115 Otherwise, 1 is returned.
118 remqueue (SCM q
, SCM c
)
121 SCM_CRITICAL_SECTION_START
;
122 for (p
= SCM_CDR (q
); !scm_is_null (p
); p
= SCM_CDR (p
))
124 if (scm_is_eq (p
, c
))
126 if (scm_is_eq (c
, SCM_CAR (q
)))
127 SCM_SETCAR (q
, SCM_CDR (c
));
128 SCM_SETCDR (prev
, SCM_CDR (c
));
129 SCM_CRITICAL_SECTION_END
;
134 SCM_CRITICAL_SECTION_END
;
138 /* Remove the front-most element from the queue Q and return it.
139 Return SCM_BOOL_F when Q is empty.
145 SCM_CRITICAL_SECTION_START
;
149 SCM_CRITICAL_SECTION_END
;
154 SCM_SETCDR (q
, SCM_CDR (c
));
155 if (scm_is_null (SCM_CDR (q
)))
156 SCM_SETCAR (q
, SCM_EOL
);
157 SCM_CRITICAL_SECTION_END
;
162 /*** Thread smob routines */
165 thread_mark (SCM obj
)
167 scm_i_thread
*t
= SCM_I_THREAD_DATA (obj
);
168 scm_gc_mark (t
->result
);
169 scm_gc_mark (t
->cleanup_handler
);
170 scm_gc_mark (t
->join_queue
);
171 scm_gc_mark (t
->mutexes
);
172 scm_gc_mark (t
->dynwinds
);
173 scm_gc_mark (t
->active_asyncs
);
174 scm_gc_mark (t
->continuation_root
);
176 return t
->dynamic_state
;
180 thread_print (SCM exp
, SCM port
, scm_print_state
*pstate SCM_UNUSED
)
182 /* On a Gnu system pthread_t is an unsigned long, but on mingw it's a
183 struct. A cast like "(unsigned long) t->pthread" is a syntax error in
184 the struct case, hence we go via a union, and extract according to the
185 size of pthread_t. */
193 scm_i_thread
*t
= SCM_I_THREAD_DATA (exp
);
194 scm_i_pthread_t p
= t
->pthread
;
197 if (sizeof (p
) == sizeof (unsigned short))
199 else if (sizeof (p
) == sizeof (unsigned int))
201 else if (sizeof (p
) == sizeof (unsigned long))
206 scm_puts ("#<thread ", port
);
207 scm_uintprint (id
, 10, port
);
208 scm_puts (" (", port
);
209 scm_uintprint ((scm_t_bits
)t
, 16, port
);
210 scm_puts (")>", port
);
215 thread_free (SCM obj
)
217 scm_i_thread
*t
= SCM_I_THREAD_DATA (obj
);
219 scm_gc_free (t
, sizeof (*t
), "thread");
223 /*** Blocking on queues. */
225 /* See also scm_i_queue_async_cell for how such a block is
229 /* Put the current thread on QUEUE and go to sleep, waiting for it to
230 be woken up by a call to 'unblock_from_queue', or to be
231 interrupted. Upon return of this function, the current thread is
232 no longer on QUEUE, even when the sleep has been interrupted.
234 The caller of block_self must hold MUTEX. It will be atomically
235 unlocked while sleeping, just as with scm_i_pthread_cond_wait.
237 SLEEP_OBJECT is an arbitrary SCM value that is kept alive as long
240 When WAITTIME is not NULL, the sleep will be aborted at that time.
242 The return value of block_self is an errno value. It will be zero
243 when the sleep has been successfully completed by a call to
244 unblock_from_queue, EINTR when it has been interrupted by the
245 delivery of a system async, and ETIMEDOUT when the timeout has
248 The system asyncs themselves are not executed by block_self.
251 block_self (SCM queue
, SCM sleep_object
, scm_i_pthread_mutex_t
*mutex
,
252 const scm_t_timespec
*waittime
)
254 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
258 if (scm_i_setup_sleep (t
, sleep_object
, mutex
, -1))
263 q_handle
= enqueue (queue
, t
->handle
);
264 if (waittime
== NULL
)
265 err
= scm_i_scm_pthread_cond_wait (&t
->sleep_cond
, mutex
);
267 err
= scm_i_scm_pthread_cond_timedwait (&t
->sleep_cond
, mutex
, waittime
);
269 /* When we are still on QUEUE, we have been interrupted. We
270 report this only when no other error (such as a timeout) has
273 if (remqueue (queue
, q_handle
) && err
== 0)
276 scm_i_reset_sleep (t
);
282 /* Wake up the first thread on QUEUE, if any. The awoken thread is
283 returned, or #f if the queue was empty.
286 unblock_from_queue (SCM queue
)
288 SCM thread
= dequeue (queue
);
289 if (scm_is_true (thread
))
290 scm_i_pthread_cond_signal (&SCM_I_THREAD_DATA(thread
)->sleep_cond
);
294 /* Getting into and out of guile mode.
297 /* Ken Raeburn observes that the implementation of suspend and resume
298 (and the things that build on top of them) are very likely not
299 correct (see below). We will need fix this eventually, and that's
300 why scm_leave_guile/scm_enter_guile are not exported in the API.
304 Consider this sequence:
306 Function foo, called in Guile mode, calls suspend (maybe indirectly
307 through scm_leave_guile), which does this:
309 // record top of stack for the GC
310 t->top = SCM_STACK_PTR (&t); // just takes address of automatic
313 SCM_FLUSH_REGISTER_WINDOWS; // sparc only
314 setjmp (t->regs); // here's most of the magic
318 Function foo has a SCM value X, a handle on a non-immediate object, in
319 a caller-saved register R, and it's the only reference to the object
322 The compiler wants to use R in suspend, so it pushes the current
323 value, X, into a stack slot which will be reloaded on exit from
324 suspend; then it loads stuff into R and goes about its business. The
325 setjmp call saves (some of) the current registers, including R, which
326 no longer contains X. (This isn't a problem for a normal
327 setjmp/longjmp situation, where longjmp would be called before
328 setjmp's caller returns; the old value for X would be loaded back from
329 the stack after the longjmp, before the function returned.)
331 So, suspend returns, loading X back into R (and invalidating the jump
332 buffer) in the process. The caller foo then goes off and calls a
333 bunch of other functions out of Guile mode, occasionally storing X on
334 the stack again, but, say, much deeper on the stack than suspend's
335 stack frame went, and the stack slot where suspend had written X has
336 long since been overwritten with other values.
338 Okay, nothing actively broken so far. Now, let garbage collection
339 run, triggered by another thread.
341 The thread calling foo is out of Guile mode at the time, so the
342 garbage collector just scans a range of stack addresses. Too bad that
343 X isn't stored there. So the pointed-to storage goes onto the free
344 list, and I think you can see where things go from there.
346 Is there anything I'm missing that'll prevent this scenario from
347 happening? I mean, aside from, "well, suspend and scm_leave_guile
348 don't have many local variables, so they probably won't need to save
349 any registers on most systems, so we hope everything will wind up in
350 the jump buffer and we'll just get away with it"?
352 (And, going the other direction, if scm_leave_guile and suspend push
353 the stack pointer over onto a new page, and foo doesn't make further
354 function calls and thus the stack pointer no longer includes that
355 page, are we guaranteed that the kernel cannot release the now-unused
356 stack page that contains the top-of-stack pointer we just saved? I
357 don't know if any OS actually does that. If it does, we could get
358 faults in garbage collection.)
360 I don't think scm_without_guile has to have this problem, as it gets
361 more control over the stack handling -- but it should call setjmp
362 itself. I'd probably try something like:
364 // record top of stack for the GC
365 t->top = SCM_STACK_PTR (&t);
367 SCM_FLUSH_REGISTER_WINDOWS;
372 ... though even that's making some assumptions about the stack
373 ordering of local variables versus caller-saved registers.
375 For something like scm_leave_guile to work, I don't think it can just
376 rely on invalidated jump buffers. A valid jump buffer, and a handle
377 on the stack state at the point when the jump buffer was initialized,
378 together, would work fine, but I think then we're talking about macros
379 invoking setjmp in the caller's stack frame, and requiring that the
380 caller of scm_leave_guile also call scm_enter_guile before returning,
381 kind of like pthread_cleanup_push/pop calls that have to be paired up
382 in a function. (In fact, the pthread ones have to be paired up
383 syntactically, as if they might expand to a compound statement
384 incorporating the user's code, and invoking a compiler's
385 exception-handling primitives. Which might be something to think
386 about for cases where Guile is used with C++ exceptions or
390 scm_i_pthread_key_t scm_i_thread_key
;
393 resume (scm_i_thread
*t
)
396 if (t
->clear_freelists_p
)
398 *SCM_FREELIST_LOC (scm_i_freelist
) = SCM_EOL
;
399 *SCM_FREELIST_LOC (scm_i_freelist2
) = SCM_EOL
;
400 t
->clear_freelists_p
= 0;
404 typedef void* scm_t_guile_ticket
;
407 scm_enter_guile (scm_t_guile_ticket ticket
)
409 scm_i_thread
*t
= (scm_i_thread
*)ticket
;
412 scm_i_pthread_mutex_lock (&t
->heap_mutex
);
417 static scm_i_thread
*
420 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
422 /* record top of stack for the GC */
423 t
->top
= SCM_STACK_PTR (&t
);
424 /* save registers. */
425 SCM_FLUSH_REGISTER_WINDOWS
;
430 static scm_t_guile_ticket
433 scm_i_thread
*t
= suspend ();
434 scm_i_pthread_mutex_unlock (&t
->heap_mutex
);
435 return (scm_t_guile_ticket
) t
;
438 static scm_i_pthread_mutex_t thread_admin_mutex
= SCM_I_PTHREAD_MUTEX_INITIALIZER
;
439 static scm_i_thread
*all_threads
= NULL
;
440 static int thread_count
;
442 static SCM scm_i_default_dynamic_state
;
444 /* Perform first stage of thread initialisation, in non-guile mode.
447 guilify_self_1 (SCM_STACKITEM
*base
)
449 scm_i_thread
*t
= malloc (sizeof (scm_i_thread
));
451 t
->pthread
= scm_i_pthread_self ();
452 t
->handle
= SCM_BOOL_F
;
453 t
->result
= SCM_BOOL_F
;
454 t
->cleanup_handler
= SCM_BOOL_F
;
455 t
->mutexes
= SCM_EOL
;
456 t
->held_mutex
= NULL
;
457 t
->join_queue
= SCM_EOL
;
458 t
->dynamic_state
= SCM_BOOL_F
;
459 t
->dynwinds
= SCM_EOL
;
460 t
->active_asyncs
= SCM_EOL
;
462 t
->pending_asyncs
= 1;
463 t
->last_debug_frame
= NULL
;
466 /* Calculate and store off the base of this thread's register
467 backing store (RBS). Unfortunately our implementation(s) of
468 scm_ia64_register_backing_store_base are only reliable for the
469 main thread. For other threads, therefore, find out the current
470 top of the RBS, and use that as a maximum. */
471 t
->register_backing_store_base
= scm_ia64_register_backing_store_base ();
476 bsp
= scm_ia64_ar_bsp (&ctx
);
477 if (t
->register_backing_store_base
> bsp
)
478 t
->register_backing_store_base
= bsp
;
481 t
->continuation_root
= SCM_EOL
;
482 t
->continuation_base
= base
;
483 scm_i_pthread_cond_init (&t
->sleep_cond
, NULL
);
484 t
->sleep_mutex
= NULL
;
485 t
->sleep_object
= SCM_BOOL_F
;
488 if (pipe (t
->sleep_pipe
) != 0)
489 /* FIXME: Error conditions during the initialization phase are handled
490 gracelessly since public functions such as `scm_init_guile ()'
491 currently have type `void'. */
494 scm_i_pthread_mutex_init (&t
->heap_mutex
, NULL
);
495 scm_i_pthread_mutex_init (&t
->admin_mutex
, NULL
);
496 t
->clear_freelists_p
= 0;
501 t
->freelist
= SCM_EOL
;
502 t
->freelist2
= SCM_EOL
;
503 SCM_SET_FREELIST_LOC (scm_i_freelist
, &t
->freelist
);
504 SCM_SET_FREELIST_LOC (scm_i_freelist2
, &t
->freelist2
);
506 scm_i_pthread_setspecific (scm_i_thread_key
, t
);
508 scm_i_pthread_mutex_lock (&t
->heap_mutex
);
510 scm_i_pthread_mutex_lock (&thread_admin_mutex
);
511 t
->next_thread
= all_threads
;
514 scm_i_pthread_mutex_unlock (&thread_admin_mutex
);
517 /* Perform second stage of thread initialisation, in guile mode.
520 guilify_self_2 (SCM parent
)
522 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
524 SCM_NEWSMOB (t
->handle
, scm_tc16_thread
, t
);
525 scm_gc_register_collectable_memory (t
, sizeof (scm_i_thread
), "thread");
526 t
->continuation_root
= scm_cons (t
->handle
, SCM_EOL
);
527 t
->continuation_base
= t
->base
;
530 if (scm_is_true (parent
))
531 t
->dynamic_state
= scm_make_dynamic_state (parent
);
533 t
->dynamic_state
= scm_i_make_initial_dynamic_state ();
535 t
->join_queue
= make_queue ();
542 /* We implement our own mutex type since we want them to be 'fair', we
543 want to do fancy things while waiting for them (like running
544 asyncs) and we might want to add things that are nice for
549 scm_i_pthread_mutex_t lock
;
551 int level
; /* how much the owner owns us. <= 1 for non-recursive mutexes */
553 int recursive
; /* allow recursive locking? */
554 int unchecked_unlock
; /* is it an error to unlock an unlocked mutex? */
555 int allow_external_unlock
; /* is it an error to unlock a mutex that is not
556 owned by the current thread? */
558 SCM waiting
; /* the threads waiting for this mutex. */
561 #define SCM_MUTEXP(x) SCM_SMOB_PREDICATE (scm_tc16_mutex, x)
562 #define SCM_MUTEX_DATA(x) ((fat_mutex *) SCM_SMOB_DATA (x))
564 /* Perform thread tear-down, in guile mode.
567 do_thread_exit (void *v
)
569 scm_i_thread
*t
= (scm_i_thread
*) v
;
571 if (!scm_is_false (t
->cleanup_handler
))
573 SCM ptr
= t
->cleanup_handler
;
575 t
->cleanup_handler
= SCM_BOOL_F
;
576 t
->result
= scm_internal_catch (SCM_BOOL_T
,
577 (scm_t_catch_body
) scm_call_0
, ptr
,
578 scm_handle_by_message_noexit
, NULL
);
581 scm_i_scm_pthread_mutex_lock (&t
->admin_mutex
);
584 close (t
->sleep_pipe
[0]);
585 close (t
->sleep_pipe
[1]);
586 while (scm_is_true (unblock_from_queue (t
->join_queue
)))
589 while (!scm_is_null (t
->mutexes
))
591 SCM mutex
= SCM_CAR (t
->mutexes
);
592 fat_mutex
*m
= SCM_MUTEX_DATA (mutex
);
593 scm_i_pthread_mutex_lock (&m
->lock
);
595 unblock_from_queue (m
->waiting
);
597 scm_i_pthread_mutex_unlock (&m
->lock
);
598 t
->mutexes
= SCM_CDR (t
->mutexes
);
601 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
607 on_thread_exit (void *v
)
609 /* This handler is executed in non-guile mode. */
610 scm_i_thread
*t
= (scm_i_thread
*) v
, **tp
;
612 /* If this thread was cancelled while doing a cond wait, it will
613 still have a mutex locked, so we unlock it here. */
616 scm_i_pthread_mutex_unlock (t
->held_mutex
);
617 t
->held_mutex
= NULL
;
620 scm_i_pthread_setspecific (scm_i_thread_key
, v
);
622 /* Ensure the signal handling thread has been launched, because we might be
624 scm_i_ensure_signal_delivery_thread ();
626 /* Unblocking the joining threads needs to happen in guile mode
627 since the queue is a SCM data structure. */
628 scm_with_guile (do_thread_exit
, v
);
630 /* Removing ourself from the list of all threads needs to happen in
631 non-guile mode since all SCM values on our stack become
632 unprotected once we are no longer in the list. */
633 scm_i_pthread_mutex_lock (&thread_admin_mutex
);
634 for (tp
= &all_threads
; *tp
; tp
= &(*tp
)->next_thread
)
637 *tp
= t
->next_thread
;
642 /* If there's only one other thread, it could be the signal delivery
643 thread, so we need to notify it to shut down by closing its read pipe.
644 If it's not the signal delivery thread, then closing the read pipe isn't
646 if (thread_count
<= 1)
647 scm_i_close_signal_pipe ();
649 scm_i_pthread_mutex_unlock (&thread_admin_mutex
);
651 scm_i_pthread_setspecific (scm_i_thread_key
, NULL
);
654 static scm_i_pthread_once_t init_thread_key_once
= SCM_I_PTHREAD_ONCE_INIT
;
657 init_thread_key (void)
659 scm_i_pthread_key_create (&scm_i_thread_key
, on_thread_exit
);
662 /* Perform any initializations necessary to bring the current thread
663 into guile mode, initializing Guile itself, if necessary.
665 BASE is the stack base to use with GC.
667 PARENT is the dynamic state to use as the parent, ot SCM_BOOL_F in
668 which case the default dynamic state is used.
670 Return zero when the thread was in guile mode already; otherwise
675 scm_i_init_thread_for_guile (SCM_STACKITEM
*base
, SCM parent
)
679 scm_i_pthread_once (&init_thread_key_once
, init_thread_key
);
681 if ((t
= SCM_I_CURRENT_THREAD
) == NULL
)
683 /* This thread has not been guilified yet.
686 scm_i_pthread_mutex_lock (&scm_i_init_mutex
);
687 if (scm_initialized_p
== 0)
689 /* First thread ever to enter Guile. Run the full
692 scm_i_init_guile (base
);
693 scm_i_pthread_mutex_unlock (&scm_i_init_mutex
);
697 /* Guile is already initialized, but this thread enters it for
698 the first time. Only initialize this thread.
700 scm_i_pthread_mutex_unlock (&scm_i_init_mutex
);
701 guilify_self_1 (base
);
702 guilify_self_2 (parent
);
708 /* This thread is already guilified but not in guile mode, just
711 A user call to scm_with_guile() will lead us to here. This could
712 happen from anywhere on the stack, and in particular lower on the
713 stack than when it was when this thread was first guilified. Thus,
714 `base' must be updated. */
715 #if SCM_STACK_GROWS_UP
723 scm_enter_guile ((scm_t_guile_ticket
) t
);
728 /* Thread is already in guile mode. Nothing to do.
734 #if SCM_USE_PTHREAD_THREADS
736 #if HAVE_PTHREAD_ATTR_GETSTACK && HAVE_PTHREAD_GETATTR_NP
737 /* This method for GNU/Linux and perhaps some other systems.
738 It's not for MacOS X or Solaris 10, since pthread_getattr_np is not
739 available on them. */
740 #define HAVE_GET_THREAD_STACK_BASE
742 static SCM_STACKITEM
*
743 get_thread_stack_base ()
749 pthread_getattr_np (pthread_self (), &attr
);
750 pthread_attr_getstack (&attr
, &start
, &size
);
751 end
= (char *)start
+ size
;
753 /* XXX - pthread_getattr_np from LinuxThreads does not seem to work
754 for the main thread, but we can use scm_get_stack_base in that
758 #ifndef PTHREAD_ATTR_GETSTACK_WORKS
759 if ((void *)&attr
< start
|| (void *)&attr
>= end
)
760 return scm_get_stack_base ();
764 #if SCM_STACK_GROWS_UP
772 #elif HAVE_PTHREAD_GET_STACKADDR_NP
773 /* This method for MacOS X.
774 It'd be nice if there was some documentation on pthread_get_stackaddr_np,
775 but as of 2006 there's nothing obvious at apple.com. */
776 #define HAVE_GET_THREAD_STACK_BASE
777 static SCM_STACKITEM
*
778 get_thread_stack_base ()
780 return pthread_get_stackaddr_np (pthread_self ());
783 #elif defined (__MINGW32__)
784 /* This method for mingw. In mingw the basic scm_get_stack_base can be used
785 in any thread. We don't like hard-coding the name of a system, but there
786 doesn't seem to be a cleaner way of knowing scm_get_stack_base can
788 #define HAVE_GET_THREAD_STACK_BASE
789 static SCM_STACKITEM
*
790 get_thread_stack_base ()
792 return scm_get_stack_base ();
795 #endif /* pthread methods of get_thread_stack_base */
797 #else /* !SCM_USE_PTHREAD_THREADS */
799 #define HAVE_GET_THREAD_STACK_BASE
801 static SCM_STACKITEM
*
802 get_thread_stack_base ()
804 return scm_get_stack_base ();
807 #endif /* !SCM_USE_PTHREAD_THREADS */
809 #ifdef HAVE_GET_THREAD_STACK_BASE
814 scm_i_init_thread_for_guile (get_thread_stack_base (),
815 scm_i_default_dynamic_state
);
821 scm_with_guile (void *(*func
)(void *), void *data
)
823 return scm_i_with_guile_and_parent (func
, data
,
824 scm_i_default_dynamic_state
);
827 SCM_UNUSED
static void
828 scm_leave_guile_cleanup (void *x
)
834 scm_i_with_guile_and_parent (void *(*func
)(void *), void *data
, SCM parent
)
838 SCM_STACKITEM base_item
;
840 really_entered
= scm_i_init_thread_for_guile (&base_item
, parent
);
843 scm_i_pthread_cleanup_push (scm_leave_guile_cleanup
, NULL
);
844 res
= scm_c_with_continuation_barrier (func
, data
);
845 scm_i_pthread_cleanup_pop (0);
849 res
= scm_c_with_continuation_barrier (func
, data
);
855 scm_without_guile (void *(*func
)(void *), void *data
)
858 scm_t_guile_ticket t
;
859 t
= scm_leave_guile ();
865 /*** Thread creation */
872 scm_i_pthread_mutex_t mutex
;
873 scm_i_pthread_cond_t cond
;
877 really_launch (void *d
)
879 launch_data
*data
= (launch_data
*)d
;
880 SCM thunk
= data
->thunk
, handler
= data
->handler
;
883 t
= SCM_I_CURRENT_THREAD
;
885 scm_i_scm_pthread_mutex_lock (&data
->mutex
);
886 data
->thread
= scm_current_thread ();
887 scm_i_pthread_cond_signal (&data
->cond
);
888 scm_i_pthread_mutex_unlock (&data
->mutex
);
890 if (SCM_UNBNDP (handler
))
891 t
->result
= scm_call_0 (thunk
);
893 t
->result
= scm_catch (SCM_BOOL_T
, thunk
, handler
);
899 launch_thread (void *d
)
901 launch_data
*data
= (launch_data
*)d
;
902 scm_i_pthread_detach (scm_i_pthread_self ());
903 scm_i_with_guile_and_parent (really_launch
, d
, data
->parent
);
907 SCM_DEFINE (scm_call_with_new_thread
, "call-with-new-thread", 1, 1, 0,
908 (SCM thunk
, SCM handler
),
909 "Call @code{thunk} in a new thread and with a new dynamic state,\n"
910 "returning a new thread object representing the thread. The procedure\n"
911 "@var{thunk} is called via @code{with-continuation-barrier}.\n"
913 "When @var{handler} is specified, then @var{thunk} is called from\n"
914 "within a @code{catch} with tag @code{#t} that has @var{handler} as its\n"
915 "handler. This catch is established inside the continuation barrier.\n"
917 "Once @var{thunk} or @var{handler} returns, the return value is made\n"
918 "the @emph{exit value} of the thread and the thread is terminated.")
919 #define FUNC_NAME s_scm_call_with_new_thread
925 SCM_ASSERT (scm_is_true (scm_thunk_p (thunk
)), thunk
, SCM_ARG1
, FUNC_NAME
);
926 SCM_ASSERT (SCM_UNBNDP (handler
) || scm_is_true (scm_procedure_p (handler
)),
927 handler
, SCM_ARG2
, FUNC_NAME
);
929 data
.parent
= scm_current_dynamic_state ();
931 data
.handler
= handler
;
932 data
.thread
= SCM_BOOL_F
;
933 scm_i_pthread_mutex_init (&data
.mutex
, NULL
);
934 scm_i_pthread_cond_init (&data
.cond
, NULL
);
936 scm_i_scm_pthread_mutex_lock (&data
.mutex
);
937 err
= scm_i_pthread_create (&id
, NULL
, launch_thread
, &data
);
940 scm_i_pthread_mutex_unlock (&data
.mutex
);
944 scm_i_scm_pthread_cond_wait (&data
.cond
, &data
.mutex
);
945 scm_i_pthread_mutex_unlock (&data
.mutex
);
953 scm_t_catch_body body
;
955 scm_t_catch_handler handler
;
958 scm_i_pthread_mutex_t mutex
;
959 scm_i_pthread_cond_t cond
;
963 really_spawn (void *d
)
965 spawn_data
*data
= (spawn_data
*)d
;
966 scm_t_catch_body body
= data
->body
;
967 void *body_data
= data
->body_data
;
968 scm_t_catch_handler handler
= data
->handler
;
969 void *handler_data
= data
->handler_data
;
970 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
972 scm_i_scm_pthread_mutex_lock (&data
->mutex
);
973 data
->thread
= scm_current_thread ();
974 scm_i_pthread_cond_signal (&data
->cond
);
975 scm_i_pthread_mutex_unlock (&data
->mutex
);
978 t
->result
= body (body_data
);
980 t
->result
= scm_internal_catch (SCM_BOOL_T
,
982 handler
, handler_data
);
988 spawn_thread (void *d
)
990 spawn_data
*data
= (spawn_data
*)d
;
991 scm_i_pthread_detach (scm_i_pthread_self ());
992 scm_i_with_guile_and_parent (really_spawn
, d
, data
->parent
);
997 scm_spawn_thread (scm_t_catch_body body
, void *body_data
,
998 scm_t_catch_handler handler
, void *handler_data
)
1004 data
.parent
= scm_current_dynamic_state ();
1006 data
.body_data
= body_data
;
1007 data
.handler
= handler
;
1008 data
.handler_data
= handler_data
;
1009 data
.thread
= SCM_BOOL_F
;
1010 scm_i_pthread_mutex_init (&data
.mutex
, NULL
);
1011 scm_i_pthread_cond_init (&data
.cond
, NULL
);
1013 scm_i_scm_pthread_mutex_lock (&data
.mutex
);
1014 err
= scm_i_pthread_create (&id
, NULL
, spawn_thread
, &data
);
1017 scm_i_pthread_mutex_unlock (&data
.mutex
);
1019 scm_syserror (NULL
);
1021 scm_i_scm_pthread_cond_wait (&data
.cond
, &data
.mutex
);
1022 scm_i_pthread_mutex_unlock (&data
.mutex
);
1027 SCM_DEFINE (scm_yield
, "yield", 0, 0, 0,
1029 "Move the calling thread to the end of the scheduling queue.")
1030 #define FUNC_NAME s_scm_yield
1032 return scm_from_bool (scm_i_sched_yield ());
1036 SCM_DEFINE (scm_cancel_thread
, "cancel-thread", 1, 0, 0,
1038 "Asynchronously force the target @var{thread} to terminate. @var{thread} "
1039 "cannot be the current thread, and if @var{thread} has already terminated or "
1040 "been signaled to terminate, this function is a no-op.")
1041 #define FUNC_NAME s_scm_cancel_thread
1043 scm_i_thread
*t
= NULL
;
1045 SCM_VALIDATE_THREAD (1, thread
);
1046 t
= SCM_I_THREAD_DATA (thread
);
1047 scm_i_scm_pthread_mutex_lock (&t
->admin_mutex
);
1051 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1052 scm_i_pthread_cancel (t
->pthread
);
1055 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1057 return SCM_UNSPECIFIED
;
1061 SCM_DEFINE (scm_set_thread_cleanup_x
, "set-thread-cleanup!", 2, 0, 0,
1062 (SCM thread
, SCM proc
),
1063 "Set the thunk @var{proc} as the cleanup handler for the thread @var{thread}. "
1064 "This handler will be called when the thread exits.")
1065 #define FUNC_NAME s_scm_set_thread_cleanup_x
1069 SCM_VALIDATE_THREAD (1, thread
);
1070 if (!scm_is_false (proc
))
1071 SCM_VALIDATE_THUNK (2, proc
);
1073 t
= SCM_I_THREAD_DATA (thread
);
1074 scm_i_pthread_mutex_lock (&t
->admin_mutex
);
1076 if (!(t
->exited
|| t
->canceled
))
1077 t
->cleanup_handler
= proc
;
1079 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1081 return SCM_UNSPECIFIED
;
1085 SCM_DEFINE (scm_thread_cleanup
, "thread-cleanup", 1, 0, 0,
1087 "Return the cleanup handler installed for the thread @var{thread}.")
1088 #define FUNC_NAME s_scm_thread_cleanup
1093 SCM_VALIDATE_THREAD (1, thread
);
1095 t
= SCM_I_THREAD_DATA (thread
);
1096 scm_i_pthread_mutex_lock (&t
->admin_mutex
);
1097 ret
= (t
->exited
|| t
->canceled
) ? SCM_BOOL_F
: t
->cleanup_handler
;
1098 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1104 SCM
scm_join_thread (SCM thread
)
1106 return scm_join_thread_timed (thread
, SCM_UNDEFINED
, SCM_UNDEFINED
);
1109 SCM_DEFINE (scm_join_thread_timed
, "join-thread", 1, 2, 0,
1110 (SCM thread
, SCM timeout
, SCM timeoutval
),
1111 "Suspend execution of the calling thread until the target @var{thread} "
1112 "terminates, unless the target @var{thread} has already terminated. ")
1113 #define FUNC_NAME s_scm_join_thread_timed
1116 scm_t_timespec ctimeout
, *timeout_ptr
= NULL
;
1117 SCM res
= SCM_BOOL_F
;
1119 if (! (SCM_UNBNDP (timeoutval
)))
1122 SCM_VALIDATE_THREAD (1, thread
);
1123 if (scm_is_eq (scm_current_thread (), thread
))
1124 SCM_MISC_ERROR ("cannot join the current thread", SCM_EOL
);
1126 t
= SCM_I_THREAD_DATA (thread
);
1127 scm_i_scm_pthread_mutex_lock (&t
->admin_mutex
);
1129 if (! SCM_UNBNDP (timeout
))
1131 to_timespec (timeout
, &ctimeout
);
1132 timeout_ptr
= &ctimeout
;
1141 int err
= block_self (t
->join_queue
, thread
, &t
->admin_mutex
,
1151 else if (err
== ETIMEDOUT
)
1154 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1156 scm_i_scm_pthread_mutex_lock (&t
->admin_mutex
);
1160 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1166 SCM_DEFINE (scm_thread_p
, "thread?", 1, 0, 0,
1168 "Return @code{#t} if @var{obj} is a thread.")
1169 #define FUNC_NAME s_scm_thread_p
1171 return SCM_I_IS_THREAD(obj
) ? SCM_BOOL_T
: SCM_BOOL_F
;
1176 fat_mutex_mark (SCM mx
)
1178 fat_mutex
*m
= SCM_MUTEX_DATA (mx
);
1179 scm_gc_mark (m
->owner
);
1184 fat_mutex_free (SCM mx
)
1186 fat_mutex
*m
= SCM_MUTEX_DATA (mx
);
1187 scm_i_pthread_mutex_destroy (&m
->lock
);
1188 scm_gc_free (m
, sizeof (fat_mutex
), "mutex");
1193 fat_mutex_print (SCM mx
, SCM port
, scm_print_state
*pstate SCM_UNUSED
)
1195 fat_mutex
*m
= SCM_MUTEX_DATA (mx
);
1196 scm_puts ("#<mutex ", port
);
1197 scm_uintprint ((scm_t_bits
)m
, 16, port
);
1198 scm_puts (">", port
);
1203 make_fat_mutex (int recursive
, int unchecked_unlock
, int external_unlock
)
1208 m
= scm_gc_malloc (sizeof (fat_mutex
), "mutex");
1209 scm_i_pthread_mutex_init (&m
->lock
, NULL
);
1210 m
->owner
= SCM_BOOL_F
;
1213 m
->recursive
= recursive
;
1214 m
->unchecked_unlock
= unchecked_unlock
;
1215 m
->allow_external_unlock
= external_unlock
;
1217 m
->waiting
= SCM_EOL
;
1218 SCM_NEWSMOB (mx
, scm_tc16_mutex
, (scm_t_bits
) m
);
1219 m
->waiting
= make_queue ();
1223 SCM
scm_make_mutex (void)
1225 return scm_make_mutex_with_flags (SCM_EOL
);
1228 SCM_SYMBOL (unchecked_unlock_sym
, "unchecked-unlock");
1229 SCM_SYMBOL (allow_external_unlock_sym
, "allow-external-unlock");
1230 SCM_SYMBOL (recursive_sym
, "recursive");
1232 SCM_DEFINE (scm_make_mutex_with_flags
, "make-mutex", 0, 0, 1,
1234 "Create a new mutex. ")
1235 #define FUNC_NAME s_scm_make_mutex_with_flags
1237 int unchecked_unlock
= 0, external_unlock
= 0, recursive
= 0;
1240 while (! scm_is_null (ptr
))
1242 SCM flag
= SCM_CAR (ptr
);
1243 if (scm_is_eq (flag
, unchecked_unlock_sym
))
1244 unchecked_unlock
= 1;
1245 else if (scm_is_eq (flag
, allow_external_unlock_sym
))
1246 external_unlock
= 1;
1247 else if (scm_is_eq (flag
, recursive_sym
))
1250 SCM_MISC_ERROR ("unsupported mutex option: ~a", scm_list_1 (flag
));
1251 ptr
= SCM_CDR (ptr
);
1253 return make_fat_mutex (recursive
, unchecked_unlock
, external_unlock
);
1257 SCM_DEFINE (scm_make_recursive_mutex
, "make-recursive-mutex", 0, 0, 0,
1259 "Create a new recursive mutex. ")
1260 #define FUNC_NAME s_scm_make_recursive_mutex
1262 return make_fat_mutex (1, 0, 0);
1266 SCM_SYMBOL (scm_abandoned_mutex_error_key
, "abandoned-mutex-error");
1269 fat_mutex_lock (SCM mutex
, scm_t_timespec
*timeout
, SCM owner
, int *ret
)
1271 fat_mutex
*m
= SCM_MUTEX_DATA (mutex
);
1273 SCM new_owner
= SCM_UNBNDP (owner
) ? scm_current_thread() : owner
;
1274 SCM err
= SCM_BOOL_F
;
1276 struct timeval current_time
;
1278 scm_i_scm_pthread_mutex_lock (&m
->lock
);
1284 m
->owner
= new_owner
;
1287 if (SCM_I_IS_THREAD (new_owner
))
1289 scm_i_thread
*t
= SCM_I_THREAD_DATA (new_owner
);
1290 scm_i_pthread_mutex_lock (&t
->admin_mutex
);
1291 t
->mutexes
= scm_cons (mutex
, t
->mutexes
);
1292 scm_i_pthread_mutex_unlock (&t
->admin_mutex
);
1297 else if (SCM_I_IS_THREAD (m
->owner
) && scm_c_thread_exited_p (m
->owner
))
1299 m
->owner
= new_owner
;
1300 err
= scm_cons (scm_abandoned_mutex_error_key
,
1301 scm_from_locale_string ("lock obtained on abandoned "
1306 else if (scm_is_eq (m
->owner
, new_owner
))
1315 err
= scm_cons (scm_misc_error_key
,
1316 scm_from_locale_string ("mutex already locked "
1324 if (timeout
!= NULL
)
1326 gettimeofday (¤t_time
, NULL
);
1327 if (current_time
.tv_sec
> timeout
->tv_sec
||
1328 (current_time
.tv_sec
== timeout
->tv_sec
&&
1329 current_time
.tv_usec
* 1000 > timeout
->tv_nsec
))
1335 block_self (m
->waiting
, mutex
, &m
->lock
, timeout
);
1336 scm_i_pthread_mutex_unlock (&m
->lock
);
1338 scm_i_scm_pthread_mutex_lock (&m
->lock
);
1341 scm_i_pthread_mutex_unlock (&m
->lock
);
1345 SCM
scm_lock_mutex (SCM mx
)
1347 return scm_lock_mutex_timed (mx
, SCM_UNDEFINED
, SCM_UNDEFINED
);
1350 SCM_DEFINE (scm_lock_mutex_timed
, "lock-mutex", 1, 2, 0,
1351 (SCM m
, SCM timeout
, SCM owner
),
1352 "Lock @var{mutex}. If the mutex is already locked, the calling thread "
1353 "blocks until the mutex becomes available. The function returns when "
1354 "the calling thread owns the lock on @var{mutex}. Locking a mutex that "
1355 "a thread already owns will succeed right away and will not block the "
1356 "thread. That is, Guile's mutexes are @emph{recursive}. ")
1357 #define FUNC_NAME s_scm_lock_mutex_timed
1361 scm_t_timespec cwaittime
, *waittime
= NULL
;
1363 SCM_VALIDATE_MUTEX (1, m
);
1365 if (! SCM_UNBNDP (timeout
) && ! scm_is_false (timeout
))
1367 to_timespec (timeout
, &cwaittime
);
1368 waittime
= &cwaittime
;
1371 exception
= fat_mutex_lock (m
, waittime
, owner
, &ret
);
1372 if (!scm_is_false (exception
))
1373 scm_ithrow (SCM_CAR (exception
), scm_list_1 (SCM_CDR (exception
)), 1);
1374 return ret
? SCM_BOOL_T
: SCM_BOOL_F
;
1379 scm_dynwind_lock_mutex (SCM mutex
)
1381 scm_dynwind_unwind_handler_with_scm ((void(*)(SCM
))scm_unlock_mutex
, mutex
,
1382 SCM_F_WIND_EXPLICITLY
);
1383 scm_dynwind_rewind_handler_with_scm ((void(*)(SCM
))scm_lock_mutex
, mutex
,
1384 SCM_F_WIND_EXPLICITLY
);
1387 SCM_DEFINE (scm_try_mutex
, "try-mutex", 1, 0, 0,
1389 "Try to lock @var{mutex}. If the mutex is already locked by someone "
1390 "else, return @code{#f}. Else lock the mutex and return @code{#t}. ")
1391 #define FUNC_NAME s_scm_try_mutex
1395 scm_t_timespec cwaittime
, *waittime
= NULL
;
1397 SCM_VALIDATE_MUTEX (1, mutex
);
1399 to_timespec (scm_from_int(0), &cwaittime
);
1400 waittime
= &cwaittime
;
1402 exception
= fat_mutex_lock (mutex
, waittime
, SCM_UNDEFINED
, &ret
);
1403 if (!scm_is_false (exception
))
1404 scm_ithrow (SCM_CAR (exception
), scm_list_1 (SCM_CDR (exception
)), 1);
1405 return ret
? SCM_BOOL_T
: SCM_BOOL_F
;
1409 /*** Fat condition variables */
1412 scm_i_pthread_mutex_t lock
;
1413 SCM waiting
; /* the threads waiting for this condition. */
1416 #define SCM_CONDVARP(x) SCM_SMOB_PREDICATE (scm_tc16_condvar, x)
1417 #define SCM_CONDVAR_DATA(x) ((fat_cond *) SCM_SMOB_DATA (x))
1420 fat_mutex_unlock (SCM mutex
, SCM cond
,
1421 const scm_t_timespec
*waittime
, int relock
)
1423 fat_mutex
*m
= SCM_MUTEX_DATA (mutex
);
1425 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
1426 int err
= 0, ret
= 0;
1428 scm_i_scm_pthread_mutex_lock (&m
->lock
);
1430 SCM owner
= m
->owner
;
1432 if (!scm_is_eq (owner
, scm_current_thread ()))
1436 if (!m
->unchecked_unlock
)
1438 scm_i_pthread_mutex_unlock (&m
->lock
);
1439 scm_misc_error (NULL
, "mutex not locked", SCM_EOL
);
1441 owner
= scm_current_thread ();
1443 else if (!m
->allow_external_unlock
)
1445 scm_i_pthread_mutex_unlock (&m
->lock
);
1446 scm_misc_error (NULL
, "mutex not locked by current thread", SCM_EOL
);
1450 if (! (SCM_UNBNDP (cond
)))
1452 c
= SCM_CONDVAR_DATA (cond
);
1460 m
->owner
= unblock_from_queue (m
->waiting
);
1464 err
= block_self (c
->waiting
, cond
, &m
->lock
, waittime
);
1465 scm_i_pthread_mutex_unlock (&m
->lock
);
1472 else if (err
== ETIMEDOUT
)
1477 else if (err
!= EINTR
)
1480 scm_syserror (NULL
);
1486 scm_lock_mutex_timed (mutex
, SCM_UNDEFINED
, owner
);
1493 scm_remember_upto_here_2 (cond
, mutex
);
1495 scm_i_scm_pthread_mutex_lock (&m
->lock
);
1503 m
->owner
= unblock_from_queue (m
->waiting
);
1505 scm_i_pthread_mutex_unlock (&m
->lock
);
1512 SCM
scm_unlock_mutex (SCM mx
)
1514 return scm_unlock_mutex_timed (mx
, SCM_UNDEFINED
, SCM_UNDEFINED
);
1517 SCM_DEFINE (scm_unlock_mutex_timed
, "unlock-mutex", 1, 2, 0,
1518 (SCM mx
, SCM cond
, SCM timeout
),
1519 "Unlocks @var{mutex} if the calling thread owns the lock on "
1520 "@var{mutex}. Calling unlock-mutex on a mutex not owned by the current "
1521 "thread results in undefined behaviour. Once a mutex has been unlocked, "
1522 "one thread blocked on @var{mutex} is awakened and grabs the mutex "
1523 "lock. Every call to @code{lock-mutex} by this thread must be matched "
1524 "with a call to @code{unlock-mutex}. Only the last call to "
1525 "@code{unlock-mutex} will actually unlock the mutex. ")
1526 #define FUNC_NAME s_scm_unlock_mutex_timed
1528 scm_t_timespec cwaittime
, *waittime
= NULL
;
1530 SCM_VALIDATE_MUTEX (1, mx
);
1531 if (! (SCM_UNBNDP (cond
)))
1533 SCM_VALIDATE_CONDVAR (2, cond
);
1535 if (! (SCM_UNBNDP (timeout
)))
1537 to_timespec (timeout
, &cwaittime
);
1538 waittime
= &cwaittime
;
1542 return fat_mutex_unlock (mx
, cond
, waittime
, 0) ? SCM_BOOL_T
: SCM_BOOL_F
;
1546 SCM_DEFINE (scm_mutex_p
, "mutex?", 1, 0, 0,
1548 "Return @code{#t} if @var{obj} is a mutex.")
1549 #define FUNC_NAME s_scm_mutex_p
1551 return SCM_MUTEXP (obj
) ? SCM_BOOL_T
: SCM_BOOL_F
;
1555 SCM_DEFINE (scm_mutex_owner
, "mutex-owner", 1, 0, 0,
1557 "Return the thread owning @var{mx}, or @code{#f}.")
1558 #define FUNC_NAME s_scm_mutex_owner
1561 fat_mutex
*m
= NULL
;
1563 SCM_VALIDATE_MUTEX (1, mx
);
1564 m
= SCM_MUTEX_DATA (mx
);
1565 scm_i_pthread_mutex_lock (&m
->lock
);
1567 scm_i_pthread_mutex_unlock (&m
->lock
);
1573 SCM_DEFINE (scm_mutex_level
, "mutex-level", 1, 0, 0,
1575 "Return the lock level of mutex @var{mx}.")
1576 #define FUNC_NAME s_scm_mutex_level
1578 SCM_VALIDATE_MUTEX (1, mx
);
1579 return scm_from_int (SCM_MUTEX_DATA(mx
)->level
);
1583 SCM_DEFINE (scm_mutex_locked_p
, "mutex-locked?", 1, 0, 0,
1585 "Returns @code{#t} if the mutex @var{mx} is locked.")
1586 #define FUNC_NAME s_scm_mutex_locked_p
1588 SCM_VALIDATE_MUTEX (1, mx
);
1589 return SCM_MUTEX_DATA (mx
)->level
> 0 ? SCM_BOOL_T
: SCM_BOOL_F
;
1594 fat_cond_mark (SCM cv
)
1596 fat_cond
*c
= SCM_CONDVAR_DATA (cv
);
1601 fat_cond_free (SCM mx
)
1603 fat_cond
*c
= SCM_CONDVAR_DATA (mx
);
1604 scm_gc_free (c
, sizeof (fat_cond
), "condition-variable");
1609 fat_cond_print (SCM cv
, SCM port
, scm_print_state
*pstate SCM_UNUSED
)
1611 fat_cond
*c
= SCM_CONDVAR_DATA (cv
);
1612 scm_puts ("#<condition-variable ", port
);
1613 scm_uintprint ((scm_t_bits
)c
, 16, port
);
1614 scm_puts (">", port
);
1618 SCM_DEFINE (scm_make_condition_variable
, "make-condition-variable", 0, 0, 0,
1620 "Make a new condition variable.")
1621 #define FUNC_NAME s_scm_make_condition_variable
1626 c
= scm_gc_malloc (sizeof (fat_cond
), "condition variable");
1627 c
->waiting
= SCM_EOL
;
1628 SCM_NEWSMOB (cv
, scm_tc16_condvar
, (scm_t_bits
) c
);
1629 c
->waiting
= make_queue ();
1634 SCM_DEFINE (scm_timed_wait_condition_variable
, "wait-condition-variable", 2, 1, 0,
1635 (SCM cv
, SCM mx
, SCM t
),
1636 "Wait until @var{cond-var} has been signalled. While waiting, "
1637 "@var{mutex} is atomically unlocked (as with @code{unlock-mutex}) and "
1638 "is locked again when this function returns. When @var{time} is given, "
1639 "it specifies a point in time where the waiting should be aborted. It "
1640 "can be either a integer as returned by @code{current-time} or a pair "
1641 "as returned by @code{gettimeofday}. When the waiting is aborted the "
1642 "mutex is locked and @code{#f} is returned. When the condition "
1643 "variable is in fact signalled, the mutex is also locked and @code{#t} "
1645 #define FUNC_NAME s_scm_timed_wait_condition_variable
1647 scm_t_timespec waittime
, *waitptr
= NULL
;
1649 SCM_VALIDATE_CONDVAR (1, cv
);
1650 SCM_VALIDATE_MUTEX (2, mx
);
1652 if (!SCM_UNBNDP (t
))
1654 to_timespec (t
, &waittime
);
1655 waitptr
= &waittime
;
1658 return fat_mutex_unlock (mx
, cv
, waitptr
, 1) ? SCM_BOOL_T
: SCM_BOOL_F
;
1663 fat_cond_signal (fat_cond
*c
)
1665 unblock_from_queue (c
->waiting
);
1668 SCM_DEFINE (scm_signal_condition_variable
, "signal-condition-variable", 1, 0, 0,
1670 "Wake up one thread that is waiting for @var{cv}")
1671 #define FUNC_NAME s_scm_signal_condition_variable
1673 SCM_VALIDATE_CONDVAR (1, cv
);
1674 fat_cond_signal (SCM_CONDVAR_DATA (cv
));
1680 fat_cond_broadcast (fat_cond
*c
)
1682 while (scm_is_true (unblock_from_queue (c
->waiting
)))
1686 SCM_DEFINE (scm_broadcast_condition_variable
, "broadcast-condition-variable", 1, 0, 0,
1688 "Wake up all threads that are waiting for @var{cv}. ")
1689 #define FUNC_NAME s_scm_broadcast_condition_variable
1691 SCM_VALIDATE_CONDVAR (1, cv
);
1692 fat_cond_broadcast (SCM_CONDVAR_DATA (cv
));
1697 SCM_DEFINE (scm_condition_variable_p
, "condition-variable?", 1, 0, 0,
1699 "Return @code{#t} if @var{obj} is a condition variable.")
1700 #define FUNC_NAME s_scm_condition_variable_p
1702 return SCM_CONDVARP(obj
) ? SCM_BOOL_T
: SCM_BOOL_F
;
1706 /*** Marking stacks */
1708 /* XXX - what to do with this? Do we need to handle this for blocked
1712 # define SCM_MARK_BACKING_STORE() do { \
1714 SCM_STACKITEM * top, * bot; \
1715 getcontext (&ctx); \
1716 scm_mark_locations ((SCM_STACKITEM *) &ctx.uc_mcontext, \
1717 ((size_t) (sizeof (SCM_STACKITEM) - 1 + sizeof ctx.uc_mcontext) \
1718 / sizeof (SCM_STACKITEM))); \
1719 bot = (SCM_STACKITEM *) SCM_I_CURRENT_THREAD->register_backing_store_base; \
1720 top = (SCM_STACKITEM *) scm_ia64_ar_bsp (&ctx); \
1721 scm_mark_locations (bot, top - bot); } while (0)
1723 # define SCM_MARK_BACKING_STORE()
1727 scm_threads_mark_stacks (void)
1730 for (t
= all_threads
; t
; t
= t
->next_thread
)
1732 /* Check that thread has indeed been suspended.
1736 scm_gc_mark (t
->handle
);
1738 #if SCM_STACK_GROWS_UP
1739 scm_mark_locations (t
->base
, t
->top
- t
->base
);
1741 scm_mark_locations (t
->top
, t
->base
- t
->top
);
1743 scm_mark_locations ((void *) &t
->regs
,
1744 ((size_t) sizeof(t
->regs
)
1745 / sizeof (SCM_STACKITEM
)));
1748 SCM_MARK_BACKING_STORE ();
1754 scm_std_select (int nfds
,
1755 SELECT_TYPE
*readfds
,
1756 SELECT_TYPE
*writefds
,
1757 SELECT_TYPE
*exceptfds
,
1758 struct timeval
*timeout
)
1761 int res
, eno
, wakeup_fd
;
1762 scm_i_thread
*t
= SCM_I_CURRENT_THREAD
;
1763 scm_t_guile_ticket ticket
;
1765 if (readfds
== NULL
)
1767 FD_ZERO (&my_readfds
);
1768 readfds
= &my_readfds
;
1771 while (scm_i_setup_sleep (t
, SCM_BOOL_F
, NULL
, t
->sleep_pipe
[1]))
1774 wakeup_fd
= t
->sleep_pipe
[0];
1775 ticket
= scm_leave_guile ();
1776 FD_SET (wakeup_fd
, readfds
);
1777 if (wakeup_fd
>= nfds
)
1779 res
= select (nfds
, readfds
, writefds
, exceptfds
, timeout
);
1782 scm_enter_guile (ticket
);
1784 scm_i_reset_sleep (t
);
1786 if (res
> 0 && FD_ISSET (wakeup_fd
, readfds
))
1789 full_read (wakeup_fd
, &dummy
, 1);
1791 FD_CLR (wakeup_fd
, readfds
);
1803 /* Convenience API for blocking while in guile mode. */
1805 #if SCM_USE_PTHREAD_THREADS
1808 scm_pthread_mutex_lock (scm_i_pthread_mutex_t
*mutex
)
1810 scm_t_guile_ticket t
= scm_leave_guile ();
1811 int res
= scm_i_pthread_mutex_lock (mutex
);
1812 scm_enter_guile (t
);
1817 do_unlock (void *data
)
1819 scm_i_pthread_mutex_unlock ((scm_i_pthread_mutex_t
*)data
);
1823 scm_dynwind_pthread_mutex_lock (scm_i_pthread_mutex_t
*mutex
)
1825 scm_i_scm_pthread_mutex_lock (mutex
);
1826 scm_dynwind_unwind_handler (do_unlock
, mutex
, SCM_F_WIND_EXPLICITLY
);
1830 scm_pthread_cond_wait (scm_i_pthread_cond_t
*cond
, scm_i_pthread_mutex_t
*mutex
)
1832 scm_t_guile_ticket t
= scm_leave_guile ();
1833 ((scm_i_thread
*)t
)->held_mutex
= mutex
;
1834 int res
= scm_i_pthread_cond_wait (cond
, mutex
);
1835 ((scm_i_thread
*)t
)->held_mutex
= NULL
;
1836 scm_enter_guile (t
);
1841 scm_pthread_cond_timedwait (scm_i_pthread_cond_t
*cond
,
1842 scm_i_pthread_mutex_t
*mutex
,
1843 const scm_t_timespec
*wt
)
1845 scm_t_guile_ticket t
= scm_leave_guile ();
1846 ((scm_i_thread
*)t
)->held_mutex
= mutex
;
1847 int res
= scm_i_pthread_cond_timedwait (cond
, mutex
, wt
);
1848 ((scm_i_thread
*)t
)->held_mutex
= NULL
;
1849 scm_enter_guile (t
);
1856 scm_std_usleep (unsigned long usecs
)
1859 tv
.tv_usec
= usecs
% 1000000;
1860 tv
.tv_sec
= usecs
/ 1000000;
1861 scm_std_select (0, NULL
, NULL
, NULL
, &tv
);
1862 return tv
.tv_sec
* 1000000 + tv
.tv_usec
;
1866 scm_std_sleep (unsigned int secs
)
1871 scm_std_select (0, NULL
, NULL
, NULL
, &tv
);
1877 SCM_DEFINE (scm_current_thread
, "current-thread", 0, 0, 0,
1879 "Return the thread that called this function.")
1880 #define FUNC_NAME s_scm_current_thread
1882 return SCM_I_CURRENT_THREAD
->handle
;
1887 scm_c_make_list (size_t n
, SCM fill
)
1891 res
= scm_cons (fill
, res
);
1895 SCM_DEFINE (scm_all_threads
, "all-threads", 0, 0, 0,
1897 "Return a list of all threads.")
1898 #define FUNC_NAME s_scm_all_threads
1900 /* We can not allocate while holding the thread_admin_mutex because
1901 of the way GC is done.
1903 int n
= thread_count
;
1905 SCM list
= scm_c_make_list (n
, SCM_UNSPECIFIED
), *l
;
1907 scm_i_pthread_mutex_lock (&thread_admin_mutex
);
1909 for (t
= all_threads
; t
&& n
> 0; t
= t
->next_thread
)
1911 if (t
!= scm_i_signal_delivery_thread
)
1913 SCM_SETCAR (*l
, t
->handle
);
1914 l
= SCM_CDRLOC (*l
);
1919 scm_i_pthread_mutex_unlock (&thread_admin_mutex
);
1924 SCM_DEFINE (scm_thread_exited_p
, "thread-exited?", 1, 0, 0,
1926 "Return @code{#t} iff @var{thread} has exited.\n")
1927 #define FUNC_NAME s_scm_thread_exited_p
1929 return scm_from_bool (scm_c_thread_exited_p (thread
));
1934 scm_c_thread_exited_p (SCM thread
)
1935 #define FUNC_NAME s_scm_thread_exited_p
1938 SCM_VALIDATE_THREAD (1, thread
);
1939 t
= SCM_I_THREAD_DATA (thread
);
1944 static scm_i_pthread_cond_t wake_up_cond
;
1945 int scm_i_thread_go_to_sleep
;
1946 static int threads_initialized_p
= 0;
1949 scm_i_thread_put_to_sleep ()
1951 if (threads_initialized_p
)
1956 scm_i_pthread_mutex_lock (&thread_admin_mutex
);
1958 /* Signal all threads to go to sleep
1960 scm_i_thread_go_to_sleep
= 1;
1961 for (t
= all_threads
; t
; t
= t
->next_thread
)
1962 scm_i_pthread_mutex_lock (&t
->heap_mutex
);
1963 scm_i_thread_go_to_sleep
= 0;
1968 scm_i_thread_invalidate_freelists ()
1970 /* thread_admin_mutex is already locked. */
1973 for (t
= all_threads
; t
; t
= t
->next_thread
)
1974 if (t
!= SCM_I_CURRENT_THREAD
)
1975 t
->clear_freelists_p
= 1;
1979 scm_i_thread_wake_up ()
1981 if (threads_initialized_p
)
1985 scm_i_pthread_cond_broadcast (&wake_up_cond
);
1986 for (t
= all_threads
; t
; t
= t
->next_thread
)
1987 scm_i_pthread_mutex_unlock (&t
->heap_mutex
);
1988 scm_i_pthread_mutex_unlock (&thread_admin_mutex
);
1989 scm_enter_guile ((scm_t_guile_ticket
) SCM_I_CURRENT_THREAD
);
1994 scm_i_thread_sleep_for_gc ()
1996 scm_i_thread
*t
= suspend ();
1997 t
->held_mutex
= &t
->heap_mutex
;
1998 scm_i_pthread_cond_wait (&wake_up_cond
, &t
->heap_mutex
);
1999 t
->held_mutex
= NULL
;
2003 /* This mutex is used by SCM_CRITICAL_SECTION_START/END.
2005 scm_i_pthread_mutex_t scm_i_critical_section_mutex
;
2006 int scm_i_critical_section_level
= 0;
2008 static SCM dynwind_critical_section_mutex
;
2011 scm_dynwind_critical_section (SCM mutex
)
2013 if (scm_is_false (mutex
))
2014 mutex
= dynwind_critical_section_mutex
;
2015 scm_dynwind_lock_mutex (mutex
);
2016 scm_dynwind_block_asyncs ();
2019 /*** Initialization */
2021 scm_i_pthread_key_t scm_i_freelist
, scm_i_freelist2
;
2022 scm_i_pthread_mutex_t scm_i_misc_mutex
;
2024 #if SCM_USE_PTHREAD_THREADS
2025 pthread_mutexattr_t scm_i_pthread_mutexattr_recursive
[1];
2029 scm_threads_prehistory (SCM_STACKITEM
*base
)
2031 #if SCM_USE_PTHREAD_THREADS
2032 pthread_mutexattr_init (scm_i_pthread_mutexattr_recursive
);
2033 pthread_mutexattr_settype (scm_i_pthread_mutexattr_recursive
,
2034 PTHREAD_MUTEX_RECURSIVE
);
2037 scm_i_pthread_mutex_init (&scm_i_critical_section_mutex
,
2038 scm_i_pthread_mutexattr_recursive
);
2039 scm_i_pthread_mutex_init (&scm_i_misc_mutex
, NULL
);
2040 scm_i_pthread_cond_init (&wake_up_cond
, NULL
);
2041 scm_i_pthread_key_create (&scm_i_freelist
, NULL
);
2042 scm_i_pthread_key_create (&scm_i_freelist2
, NULL
);
2044 guilify_self_1 (base
);
2047 scm_t_bits scm_tc16_thread
;
2048 scm_t_bits scm_tc16_mutex
;
2049 scm_t_bits scm_tc16_condvar
;
2054 scm_tc16_thread
= scm_make_smob_type ("thread", sizeof (scm_i_thread
));
2055 scm_set_smob_mark (scm_tc16_thread
, thread_mark
);
2056 scm_set_smob_print (scm_tc16_thread
, thread_print
);
2057 scm_set_smob_free (scm_tc16_thread
, thread_free
);
2059 scm_tc16_mutex
= scm_make_smob_type ("mutex", sizeof (fat_mutex
));
2060 scm_set_smob_mark (scm_tc16_mutex
, fat_mutex_mark
);
2061 scm_set_smob_print (scm_tc16_mutex
, fat_mutex_print
);
2062 scm_set_smob_free (scm_tc16_mutex
, fat_mutex_free
);
2064 scm_tc16_condvar
= scm_make_smob_type ("condition-variable",
2066 scm_set_smob_mark (scm_tc16_condvar
, fat_cond_mark
);
2067 scm_set_smob_print (scm_tc16_condvar
, fat_cond_print
);
2068 scm_set_smob_free (scm_tc16_condvar
, fat_cond_free
);
2070 scm_i_default_dynamic_state
= SCM_BOOL_F
;
2071 guilify_self_2 (SCM_BOOL_F
);
2072 threads_initialized_p
= 1;
2074 dynwind_critical_section_mutex
=
2075 scm_permanent_object (scm_make_recursive_mutex ());
2079 scm_init_threads_default_dynamic_state ()
2081 SCM state
= scm_make_dynamic_state (scm_current_dynamic_state ());
2082 scm_i_default_dynamic_state
= scm_permanent_object (state
);
2086 scm_init_thread_procs ()
2088 #include "libguile/threads.x"