-/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002 Free Software Foundation, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this software; see the file COPYING. If not, write to
- * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307 USA
- *
- * As a special exception, the Free Software Foundation gives permission
- * for additional uses of the text contained in its release of GUILE.
- *
- * The exception is that, if you link the GUILE library with other files
- * to produce an executable, this does not by itself cause the
- * resulting executable to be covered by the GNU General Public License.
- * Your use of that executable is in no way restricted on account of
- * linking the GUILE library code into it.
- *
- * This exception does not however invalidate any other reasons why
- * the executable file might be covered by the GNU General Public License.
- *
- * This exception applies only to the code released by the
- * Free Software Foundation under the name GUILE. If you copy
- * code from other Free Software Foundation releases into a copy of
- * GUILE, as the General Public License permits, the exception does
- * not apply to the code that you add in this way. To avoid misleading
- * anyone as to the status of such modified files, you must delete
- * this exception notice from them.
- *
- * If you write modifications of your own for GUILE, it is your choice
- * whether to permit this exception to apply to your modifications.
- * If you do not wish that, delete this exception notice. */
-
-
-\f
-
-/* This file implements nice Scheme level threads on top of the gastly
- C level threads.
-*/
-
-#include <unistd.h>
-#include <stdio.h>
-#include <assert.h>
-#include <sys/time.h>
-
-#include "libguile/_scm.h"
-#include "libguile/validate.h"
-#include "libguile/root.h"
-#include "libguile/eval.h"
-#include "libguile/async.h"
-#include "libguile/ports.h"
-#include "libguile/threads.h"
-#include "libguile/dynwind.h"
-#include "libguile/iselect.h"
-
-/*** Queues */
-
-static SCM
-make_queue ()
-{
- return scm_cons (SCM_EOL, SCM_EOL);
-}
-
-static SCM
-enqueue (SCM q, SCM t)
-{
- SCM c = scm_cons (t, SCM_EOL);
- if (SCM_NULLP (SCM_CDR (q)))
- SCM_SETCDR (q, c);
- else
- SCM_SETCDR (SCM_CAR (q), c);
- SCM_SETCAR (q, c);
- return c;
-}
-
-static void
-remqueue (SCM q, SCM c)
-{
- SCM p, prev = q;
- for (p = SCM_CDR (q); !SCM_NULLP (p); p = SCM_CDR (p))
- {
- if (SCM_EQ_P (p, c))
- {
- if (SCM_EQ_P (c, SCM_CAR (q)))
- SCM_SETCAR (q, SCM_CDR (c));
- SCM_SETCDR (prev, SCM_CDR (c));
- return;
- }
- prev = p;
- }
- abort ();
-}
-
-static SCM
-dequeue (SCM q)
-{
- SCM c = SCM_CDR (q);
- if (SCM_NULLP (c))
- return SCM_BOOL_F;
- else
- {
- SCM_SETCDR (q, SCM_CDR (c));
- if (SCM_NULLP (SCM_CDR (q)))
- SCM_SETCAR (q, SCM_EOL);
- return SCM_CAR (c);
- }
-}
-
-/*** Threads */
-
-#define THREAD_INITIALIZED_P(t) (t->base != NULL)
-
-struct scm_thread {
-
- /* Blocking.
- */
- scm_t_cond sleep_cond;
- struct scm_thread *next_waiting;
-
- /* This mutex represents this threads right to access the heap.
- That right can temporarily be taken away by the GC. */
- scm_t_mutex heap_mutex;
- int clear_freelists_p; /* set if GC was done while thread was asleep */
-
- scm_root_state *root;
- SCM handle;
- scm_t_thread thread;
- SCM result;
- int exited;
-
- SCM joining_threads;
-
- /* For keeping track of the stack and registers. */
- SCM_STACKITEM *base;
- SCM_STACKITEM *top;
- jmp_buf regs;
-
-};
-
-static SCM
-make_thread (SCM creation_protects)
-{
- SCM z;
- scm_thread *t;
- z = scm_make_smob (scm_tc16_thread);
- t = SCM_THREAD_DATA (z);
- t->handle = z;
- t->result = creation_protects;
- t->base = NULL;
- t->joining_threads = make_queue ();
- scm_i_plugin_cond_init (&t->sleep_cond, 0);
- scm_i_plugin_mutex_init (&t->heap_mutex, 0);
- t->clear_freelists_p = 0;
- t->exited = 0;
- return z;
-}
-
-static void
-init_thread_creatant (SCM thread,
- SCM_STACKITEM *base)
-{
- scm_thread *t = SCM_THREAD_DATA (thread);
- t->thread = scm_thread_self ();
- t->base = base;
- t->top = NULL;
-}
-
-static SCM
-thread_mark (SCM obj)
-{
- scm_thread *t = SCM_THREAD_DATA (obj);
- scm_gc_mark (t->result);
- scm_gc_mark (t->joining_threads);
- return t->root->handle; /* mark root-state of this thread */
-}
-
-static int
-thread_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
-{
- scm_thread *t = SCM_THREAD_DATA (exp);
- scm_puts ("#<thread ", port);
- scm_intprint ((unsigned long)t, 16, port);
- scm_putc ('>', port);
- return 1;
-}
-
-static size_t
-thread_free (SCM obj)
-{
- scm_thread *t = SCM_THREAD_DATA (obj);
- if (!t->exited)
- abort ();
- scm_gc_free (t, sizeof (*t), "thread");
- return 0;
-}
-
-/*** Scheduling */
-
-#define cur_thread (SCM_CURRENT_THREAD->handle)
-scm_t_key scm_i_thread_key;
-scm_t_key scm_i_root_state_key;
-
-void
-scm_i_set_thread_data (void *data)
-{
- scm_thread *t = SCM_CURRENT_THREAD;
- scm_setspecific (scm_i_root_state_key, data);
- t->root = (scm_root_state *)data;
-}
-
-static void
-resume (scm_thread *t)
-{
- t->top = NULL;
- if (t->clear_freelists_p)
- {
- *SCM_FREELIST_LOC (scm_i_freelist) = SCM_EOL;
- *SCM_FREELIST_LOC (scm_i_freelist2) = SCM_EOL;
- t->clear_freelists_p = 0;
- }
-}
-
-void
-scm_i_enter_guile (scm_thread *t)
-{
- scm_i_plugin_mutex_lock (&t->heap_mutex);
- resume (t);
-}
-
-static scm_thread *
-suspend ()
-{
- scm_thread *c = SCM_CURRENT_THREAD;
-
- /* record top of stack for the GC */
- c->top = (SCM_STACKITEM *)&c;
- /* save registers. */
- SCM_FLUSH_REGISTER_WINDOWS;
- setjmp (c->regs);
-
- return c;
-}
-
-scm_thread *
-scm_i_leave_guile ()
-{
- scm_thread *t = suspend ();
- scm_i_plugin_mutex_unlock (&t->heap_mutex);
- return t;
-}
-
-/* Put the current thread to sleep until it is explicitely unblocked.
- */
-static int
-block ()
-{
- int err;
- scm_thread *t = suspend ();
- err = scm_i_plugin_cond_wait (&t->sleep_cond, &t->heap_mutex);
- resume (t);
- return err;
-}
-
-/* Put the current thread to sleep until it is explicitely unblocked
- or until a signal arrives or until time AT (absolute time) is
- reached. Return 0 when it has been unblocked; errno otherwise.
- */
-static int
-timed_block (const struct timespec *at)
-{
- int err;
- scm_thread *t = suspend ();
- err = scm_i_plugin_cond_timedwait (&t->sleep_cond, &t->heap_mutex, at);
- resume (t);
- return err;
-}
-
-/* Unblock a sleeping thread.
- */
-static void
-unblock (scm_thread *t)
-{
- scm_i_plugin_cond_signal (&t->sleep_cond);
-}
-
-/*** Thread creation */
-
-static scm_t_mutex thread_admin_mutex;
-static SCM all_threads;
-static int thread_count;
-
-typedef struct launch_data {
- SCM thread;
- SCM rootcont;
- scm_t_catch_body body;
- void *body_data;
- scm_t_catch_handler handler;
- void *handler_data;
-} launch_data;
-
-static SCM
-body_bootstrip (launch_data* data)
-{
- /* First save the new root continuation */
- data->rootcont = scm_root->rootcont;
- return (data->body) (data->body_data);
-}
-
-static SCM
-handler_bootstrip (launch_data* data, SCM tag, SCM throw_args)
-{
- scm_root->rootcont = data->rootcont;
- return (data->handler) (data->handler_data, tag, throw_args);
-}
-
-static void
-really_launch (SCM_STACKITEM *base, launch_data *data)
-{
- SCM thread;
- scm_thread *t;
- thread = data->thread;
- t = SCM_THREAD_DATA (thread);
- SCM_FREELIST_CREATE (scm_i_freelist);
- SCM_FREELIST_CREATE (scm_i_freelist2);
- scm_setspecific (scm_i_thread_key, t);
- scm_setspecific (scm_i_root_state_key, t->root);
- scm_i_plugin_mutex_lock (&t->heap_mutex); /* ensure that we "own" the heap */
- init_thread_creatant (thread, base); /* must own the heap */
-
- data->rootcont = SCM_BOOL_F;
- t->result =
- scm_internal_cwdr ((scm_t_catch_body) body_bootstrip,
- data,
- (scm_t_catch_handler) handler_bootstrip,
- data, base);
- scm_i_leave_guile (); /* release the heap */
- free (data);
-
- scm_i_plugin_mutex_lock (&thread_admin_mutex);
- all_threads = scm_delq_x (thread, all_threads);
- t->exited = 1;
- thread_count--;
- scm_i_plugin_mutex_unlock (&thread_admin_mutex);
-
- scm_thread_detach (t->thread);
-}
-
-static void *
-launch_thread (void *p)
-{
- really_launch ((SCM_STACKITEM *)&p, (launch_data *)p);
- return 0;
-}
-
-static SCM
-create_thread (scm_t_catch_body body, void *body_data,
- scm_t_catch_handler handler, void *handler_data,
- SCM protects)
-{
- SCM thread;
-
- /* Make new thread. The first thing the new thread will do is to
- lock guile_mutex. Thus, we can safely complete its
- initialization after creating it. While the new thread starts,
- all its data is protected via all_threads.
- */
-
- {
- scm_t_thread th;
- SCM root, old_winds;
- launch_data *data;
- scm_thread *t;
- int err;
-
- /* Unwind wind chain. */
- old_winds = scm_dynwinds;
- scm_dowinds (SCM_EOL, scm_ilength (scm_root->dynwinds));
-
- /* Allocate thread locals. */
- root = scm_make_root (scm_root->handle);
- data = scm_malloc (sizeof (launch_data));
-
- /* Make thread. */
- thread = make_thread (protects);
- data->thread = thread;
- data->body = body;
- data->body_data = body_data;
- data->handler = handler;
- data->handler_data = handler_data;
- t = SCM_THREAD_DATA (thread);
- /* must initialize root state pointer before the thread is linked
- into all_threads */
- t->root = SCM_ROOT_STATE (root);
-
- /* In order to avoid the need of synchronization between parent
- and child thread, we need to insert the child into all_threads
- before creation. */
- {
- SCM new_threads = scm_cons (thread, SCM_BOOL_F); /* could cause GC */
- scm_thread *parent = scm_i_leave_guile (); /* to prevent deadlock */
- scm_i_plugin_mutex_lock (&thread_admin_mutex);
- SCM_SETCDR (new_threads, all_threads);
- all_threads = new_threads;
- thread_count++;
- scm_i_plugin_mutex_unlock (&thread_admin_mutex);
- scm_i_enter_guile (parent);
- }
-
- err = scm_i_plugin_thread_create (&th, 0, launch_thread, (void *) data);
- if (err != 0)
- {
- scm_i_plugin_mutex_lock (&thread_admin_mutex);
- all_threads = scm_delq_x (thread, all_threads);
- ((scm_thread *) SCM_THREAD_DATA(thread))->exited = 1;
- thread_count--;
- scm_i_plugin_mutex_unlock (&thread_admin_mutex);
- }
-
- /* Return to old dynamic context. */
- scm_dowinds (old_winds, - scm_ilength (old_winds));
-
- if (err)
- {
- errno = err;
- scm_syserror ("create-thread");
- }
- }
-
- return thread;
-}
-
-SCM_DEFINE (scm_call_with_new_thread, "call-with-new-thread", 2, 0, 0,
- (SCM thunk, SCM handler),
-"Evaluate @var{(thunk)} in a new thread, and new dynamic context, "
-"returning a new thread object representing the thread. "
-"If an error occurs during evaluation, call error-thunk, passing it an "
-"error code describing the condition. "
-"If this happens, the error-thunk is called outside the scope of the new "
-"root -- it is called in the same dynamic context in which "
-"with-new-thread was evaluated, but not in the callers thread. "
-"All the evaluation rules for dynamic roots apply to threads.")
-#define FUNC_NAME s_scm_call_with_new_thread
-{
- SCM_ASSERT (SCM_NFALSEP (scm_thunk_p (thunk)), thunk, SCM_ARG1, FUNC_NAME);
- SCM_ASSERT (SCM_NFALSEP (scm_procedure_p (handler)), handler, SCM_ARG2,
- FUNC_NAME);
-
- return create_thread ((scm_t_catch_body) scm_call_0, thunk,
- (scm_t_catch_handler) scm_apply_1, handler,
- scm_cons (thunk, handler));
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_join_thread, "join-thread", 1, 0, 0,
- (SCM thread),
-"Suspend execution of the calling thread until the target @var{thread} "
-"terminates, unless the target @var{thread} has already terminated. ")
-#define FUNC_NAME s_scm_join_thread
-{
- scm_thread *t;
- SCM res;
-
- SCM_VALIDATE_THREAD (1, thread);
- if (SCM_EQ_P (cur_thread, thread))
- SCM_MISC_ERROR ("can not join the current thread", SCM_EOL);
-
- t = SCM_THREAD_DATA (thread);
- if (!t->exited)
- {
- scm_thread *c = scm_i_leave_guile ();
- while (!THREAD_INITIALIZED_P (t))
- SCM_TICK;
- scm_thread_join (t->thread, 0);
- scm_i_enter_guile (c);
- }
- res = t->result;
- t->result = SCM_BOOL_F;
- return res;
-}
-#undef FUNC_NAME
-
-/*** Fair mutexes */
-
-/* We implement our own mutex type since we want them to be 'fair', we
- want to do fancy things while waiting for them (like running
- asyncs) and we want to support waiting on many things at once.
- Also, we might add things that are nice for debugging.
-*/
-
-typedef struct fair_mutex {
- /* the thread currently owning the mutex, or SCM_BOOL_F. */
- scm_t_mutex lock;
- int lockedp;
- SCM owner;
- /* how much the owner owns us. */
- int level;
- /* the threads waiting for this mutex. */
- SCM waiting;
-} fair_mutex;
-
-static SCM
-fair_mutex_mark (SCM mx)
-{
- fair_mutex *m = SCM_MUTEX_DATA (mx);
- scm_gc_mark (m->owner);
- return m->waiting;
-}
-
-SCM_DEFINE (scm_make_fair_mutex, "make-fair-mutex", 0, 0, 0,
- (void),
- "Create a new fair mutex object. ")
-#define FUNC_NAME s_scm_make_fair_mutex
-{
- SCM mx = scm_make_smob (scm_tc16_fair_mutex);
- fair_mutex *m = SCM_MUTEX_DATA (mx);
- scm_i_plugin_mutex_init (&m->lock, 0);
- m->lockedp = 0;
- m->owner = SCM_BOOL_F;
- m->level = 0;
- m->waiting = make_queue ();
- return mx;
-}
-#undef FUNC_NAME
-
-static int
-fair_mutex_lock (fair_mutex *m)
-{
- scm_i_plugin_mutex_lock (&m->lock);
-#if 0
- /* Need to wait if another thread is just temporarily unlocking.
- This is happens very seldom and only when the other thread is
- between scm_mutex_unlock and scm_i_plugin_mutex_lock below. */
- while (m->lockedp)
- SCM_TICK;
- m->lockedp = 1;
-#endif
-
- if (m->owner == SCM_BOOL_F)
- m->owner = cur_thread;
- else if (m->owner == cur_thread)
- m->level++;
- else
- {
- while (1)
- {
- SCM c = enqueue (m->waiting, cur_thread);
- int err;
- /* Note: It's important that m->lock is never locked for
- any longer amount of time since that could prevent GC */
- scm_i_plugin_mutex_unlock (&m->lock);
- err = block ();
- if (m->owner == cur_thread)
- return 0;
- scm_i_plugin_mutex_lock (&m->lock);
- remqueue (m->waiting, c);
- scm_i_plugin_mutex_unlock (&m->lock);
- if (err)
- return err;
- SCM_ASYNC_TICK;
- scm_i_plugin_mutex_lock (&m->lock);
- }
- }
- scm_i_plugin_mutex_unlock (&m->lock);
- return 0;
-}
-
-static int
-fair_mutex_trylock (fair_mutex *m)
-{
- scm_i_plugin_mutex_lock (&m->lock);
- if (m->owner == SCM_BOOL_F)
- m->owner = cur_thread;
- else if (m->owner == cur_thread)
- m->level++;
- else
- {
- scm_i_plugin_mutex_unlock (&m->lock);
- return EBUSY;
- }
- scm_i_plugin_mutex_unlock (&m->lock);
- return 0;
-}
-
-static int
-fair_mutex_unlock (fair_mutex *m)
-{
- scm_i_plugin_mutex_lock (&m->lock);
- if (m->owner != cur_thread)
- {
- scm_i_plugin_mutex_unlock (&m->lock);
- return EPERM;
- }
- else if (m->level > 0)
- m->level--;
- else
- {
- SCM next = dequeue (m->waiting);
- if (!SCM_FALSEP (next))
- {
- m->owner = next;
- unblock (SCM_THREAD_DATA (next));
- }
- else
- m->owner = SCM_BOOL_F;
- }
- scm_i_plugin_mutex_unlock (&m->lock);
- return 0;
-}
-
-/*** Fair condition variables */
-
-/* Like mutexes, we implement our own condition variables using the
- primitives above.
-*/
-
-typedef struct fair_cond {
- scm_t_mutex lock;
- /* the threads waiting for this condition. */
- SCM waiting;
-} fair_cond;
-
-static SCM
-fair_cond_mark (SCM cv)
-{
- fair_cond *c = SCM_CONDVAR_DATA (cv);
- return c->waiting;
-}
-
-SCM_DEFINE (scm_make_fair_condition_variable, "make-fair-condition-variable", 0, 0, 0,
- (void),
- "Make a new fair condition variable.")
-#define FUNC_NAME s_scm_make_fair_condition_variable
-{
- SCM cv = scm_make_smob (scm_tc16_fair_condvar);
- fair_cond *c = SCM_CONDVAR_DATA (cv);
- scm_i_plugin_mutex_init (&c->lock, 0);
- c->waiting = make_queue ();
- return cv;
-}
-#undef FUNC_NAME
-
-static int
-fair_cond_timedwait (fair_cond *c,
- fair_mutex *m,
- const struct timespec *waittime)
-{
- int err;
- scm_i_plugin_mutex_lock (&c->lock);
-
- while (1)
- {
- enqueue (c->waiting, cur_thread);
- scm_i_plugin_mutex_unlock (&c->lock);
- fair_mutex_unlock (m); /*fixme* - not thread safe */
- if (waittime == NULL)
- err = block ();
- else
- err = timed_block (waittime);
- fair_mutex_lock (m);
- if (err)
- return err;
- /* XXX - check whether we have been signalled. */
- break;
- }
- return err;
-}
-
-static int
-fair_cond_signal (fair_cond *c)
-{
- SCM th;
- scm_i_plugin_mutex_lock (&c->lock);
- if (!SCM_FALSEP (th = dequeue (c->waiting)))
- unblock (SCM_THREAD_DATA (th));
- scm_i_plugin_mutex_unlock (&c->lock);
- return 0;
-}
-
-static int
-fair_cond_broadcast (fair_cond *c)
-{
- SCM th;
- scm_i_plugin_mutex_lock (&c->lock);
- while (!SCM_FALSEP (th = dequeue (c->waiting)))
- unblock (SCM_THREAD_DATA (th));
- scm_i_plugin_mutex_unlock (&c->lock);
- return 0;
-}
-
-/*** Mutexes */
-
-SCM_DEFINE (scm_make_mutex, "make-mutex", 0, 0, 0,
- (void),
- "Create a new mutex object. ")
-#define FUNC_NAME s_scm_make_mutex
-{
- SCM mx = scm_make_smob (scm_tc16_mutex);
- scm_i_plugin_mutex_init (SCM_MUTEX_DATA (mx), 0);
- return mx;
-}
-#undef FUNC_NAME
-
-/*fixme* change documentation */
-SCM_DEFINE (scm_lock_mutex, "lock-mutex", 1, 0, 0,
- (SCM mx),
-"Lock @var{mutex}. If the mutex is already locked, the calling thread "
-"blocks until the mutex becomes available. The function returns when "
-"the calling thread owns the lock on @var{mutex}. Locking a mutex that "
-"a thread already owns will succeed right away and will not block the "
-"thread. That is, Guile's mutexes are @emph{recursive}. ")
-#define FUNC_NAME s_scm_lock_mutex
-{
- int err;
- SCM_VALIDATE_MUTEX (1, mx);
-
- if (SCM_TYP16 (mx) == scm_tc16_fair_mutex)
- err = fair_mutex_lock (SCM_MUTEX_DATA (mx));
- else
- {
- scm_t_mutex *m = SCM_MUTEX_DATA (mx);
- scm_thread *t = scm_i_leave_guile ();
- err = scm_i_plugin_mutex_lock (m);
- scm_i_enter_guile (t);
- }
-
- if (err)
- {
- errno = err;
- SCM_SYSERROR;
- }
- return SCM_BOOL_T;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_try_mutex, "try-mutex", 1, 0, 0,
- (SCM mx),
-"Try to lock @var{mutex}. If the mutex is already locked by someone "
-"else, return @code{#f}. Else lock the mutex and return @code{#t}. ")
-#define FUNC_NAME s_scm_try_mutex
-{
- int err;
- SCM_VALIDATE_MUTEX (1, mx);
-
- if (SCM_TYP16 (mx) == scm_tc16_fair_mutex)
- err = fair_mutex_trylock (SCM_MUTEX_DATA (mx));
- else
- {
- scm_t_mutex *m = SCM_MUTEX_DATA (mx);
- scm_thread *t = scm_i_leave_guile ();
- err = scm_i_plugin_mutex_trylock (m);
- scm_i_enter_guile (t);
- }
-
- if (err == EBUSY)
- return SCM_BOOL_F;
-
- if (err)
- {
- errno = err;
- SCM_SYSERROR;
- }
-
- return SCM_BOOL_T;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_unlock_mutex, "unlock-mutex", 1, 0, 0,
- (SCM mx),
-"Unlocks @var{mutex} if the calling thread owns the lock on "
-"@var{mutex}. Calling unlock-mutex on a mutex not owned by the current "
-"thread results in undefined behaviour. Once a mutex has been unlocked, "
-"one thread blocked on @var{mutex} is awakened and grabs the mutex "
-"lock. Every call to @code{lock-mutex} by this thread must be matched "
-"with a call to @code{unlock-mutex}. Only the last call to "
-"@code{unlock-mutex} will actually unlock the mutex. ")
-#define FUNC_NAME s_scm_unlock_mutex
-{
- int err;
- SCM_VALIDATE_MUTEX (1, mx);
-
- if (SCM_TYP16 (mx) == scm_tc16_fair_mutex)
- {
- err = fair_mutex_unlock (SCM_MUTEX_DATA (mx));
- if (err == EPERM)
- {
- fair_mutex *m = SCM_MUTEX_DATA (mx);
- if (m->owner != cur_thread)
- {
- if (m->owner == SCM_BOOL_F)
- SCM_MISC_ERROR ("mutex not locked", SCM_EOL);
- else
- SCM_MISC_ERROR ("mutex not locked by this thread", SCM_EOL);
- }
- }
- }
- else
- {
- scm_t_mutex *m = SCM_MUTEX_DATA (mx);
- err = scm_i_plugin_mutex_unlock (m);
- }
-
- if (err)
- {
- errno = err;
- SCM_SYSERROR;
- }
- return SCM_BOOL_T;
-}
-#undef FUNC_NAME
-
-/*** Condition variables */
-
-SCM_DEFINE (scm_make_condition_variable, "make-condition-variable", 0, 0, 0,
- (void),
- "Make a new condition variable.")
-#define FUNC_NAME s_scm_make_condition_variable
-{
- SCM cv = scm_make_smob (scm_tc16_condvar);
- scm_i_plugin_cond_init (SCM_CONDVAR_DATA (cv), 0);
- return cv;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_timed_wait_condition_variable, "wait-condition-variable", 2, 1, 0,
- (SCM cv, SCM mx, SCM t),
-"Wait until @var{cond-var} has been signalled. While waiting, "
-"@var{mutex} is atomically unlocked (as with @code{unlock-mutex}) and "
-"is locked again when this function returns. When @var{time} is given, "
-"it specifies a point in time where the waiting should be aborted. It "
-"can be either a integer as returned by @code{current-time} or a pair "
-"as returned by @code{gettimeofday}. When the waiting is aborted the "
-"mutex is locked and @code{#f} is returned. When the condition "
-"variable is in fact signalled, the mutex is also locked and @code{#t} "
-"is returned. ")
-#define FUNC_NAME s_scm_timed_wait_condition_variable
-{
- struct timespec waittime;
- int err;
-
- SCM_VALIDATE_CONDVAR (1, cv);
- SCM_VALIDATE_MUTEX (2, mx);
- if (!((SCM_TYP16 (cv) == scm_tc16_condvar
- && SCM_TYP16 (mx) == scm_tc16_mutex)
- || (SCM_TYP16 (cv) == scm_tc16_fair_condvar
- && SCM_TYP16 (mx) == scm_tc16_fair_mutex)))
- SCM_MISC_ERROR ("Condition variable and mutex are of different kinds.",
- SCM_EOL);
-
- if (!SCM_UNBNDP (t))
- {
- if (SCM_CONSP (t))
- {
- SCM_VALIDATE_UINT_COPY (3, SCM_CAR (t), waittime.tv_sec);
- SCM_VALIDATE_UINT_COPY (3, SCM_CDR (t), waittime.tv_nsec);
- waittime.tv_nsec *= 1000;
- }
- else
- {
- SCM_VALIDATE_UINT_COPY (3, t, waittime.tv_sec);
- waittime.tv_nsec = 0;
- }
- }
-
- if (SCM_TYP16 (cv) == scm_tc16_fair_condvar)
- err = fair_cond_timedwait (SCM_CONDVAR_DATA (cv),
- SCM_MUTEX_DATA (mx),
- SCM_UNBNDP (t) ? NULL : &waittime);
- else
- {
- scm_t_cond *c = SCM_CONDVAR_DATA (cv);
- scm_t_mutex *m = SCM_MUTEX_DATA (mx);
- scm_thread *t = scm_i_leave_guile ();
- err = scm_i_plugin_cond_wait (c, m);
- scm_i_enter_guile (t);
- }
-
- if (err)
- {
- errno = err;
- SCM_SYSERROR;
- }
- return SCM_BOOL_T;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_signal_condition_variable, "signal-condition-variable", 1, 0, 0,
- (SCM cv),
- "Wake up one thread that is waiting for @var{cv}")
-#define FUNC_NAME s_scm_signal_condition_variable
-{
- SCM_VALIDATE_CONDVAR (1, cv);
- if (SCM_TYP16 (cv) == scm_tc16_fair_condvar)
- fair_cond_signal (SCM_CONDVAR_DATA (cv));
- else
- {
- scm_t_cond *c = SCM_CONDVAR_DATA (cv);
- scm_i_plugin_cond_signal (c);
- }
- return SCM_BOOL_T;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_broadcast_condition_variable, "broadcast-condition-variable", 1, 0, 0,
- (SCM cv),
- "Wake up all threads that are waiting for @var{cv}. ")
-#define FUNC_NAME s_scm_broadcast_condition_variable
-{
- SCM_VALIDATE_CONDVAR (1, cv);
- if (SCM_TYP16 (cv) == scm_tc16_fair_condvar)
- fair_cond_broadcast (SCM_CONDVAR_DATA (cv));
- else
- {
- scm_t_cond *c = SCM_CONDVAR_DATA (cv);
- scm_i_plugin_cond_broadcast (c);
- }
- return SCM_BOOL_T;
-}
-#undef FUNC_NAME
-
-/*** Marking stacks */
-
-/* XXX - what to do with this? Do we need to handle this for blocked
- threads as well?
-*/
-#ifdef __ia64__
-# define SCM_MARK_BACKING_STORE() do { \
- ucontext_t ctx; \
- SCM_STACKITEM * top, * bot; \
- getcontext (&ctx); \
- scm_mark_locations ((SCM_STACKITEM *) &ctx.uc_mcontext, \
- ((size_t) (sizeof (SCM_STACKITEM) - 1 + sizeof ctx.uc_mcontext) \
- / sizeof (SCM_STACKITEM))); \
- bot = (SCM_STACKITEM *) __libc_ia64_register_backing_store_base; \
- top = (SCM_STACKITEM *) ctx.uc_mcontext.sc_ar_bsp; \
- scm_mark_locations (bot, top - bot); } while (0)
-#else
-# define SCM_MARK_BACKING_STORE()
-#endif
-
-void
-scm_threads_mark_stacks (void)
-{
- volatile SCM c;
- for (c = all_threads; !SCM_NULLP (c); c = SCM_CDR (c))
- {
- scm_thread *t = SCM_THREAD_DATA (SCM_CAR (c));
- if (!THREAD_INITIALIZED_P (t))
- {
- /* Not fully initialized yet. */
- continue;
- }
- if (t->top == NULL)
- {
- long stack_len;
-#ifdef SCM_DEBUG
- if (t->thread != scm_thread_self ())
- abort ();
-#endif
- /* Active thread */
- /* stack_len is long rather than sizet in order to guarantee
- that &stack_len is long aligned */
-#ifdef STACK_GROWS_UP
- stack_len = ((SCM_STACKITEM *) (&t) -
- (SCM_STACKITEM *) thread->base);
-
- /* Protect from the C stack. This must be the first marking
- * done because it provides information about what objects
- * are "in-use" by the C code. "in-use" objects are those
- * for which the information about length and base address must
- * remain usable. This requirement is stricter than a liveness
- * requirement -- in particular, it constrains the implementation
- * of scm_resizuve.
- */
- SCM_FLUSH_REGISTER_WINDOWS;
- /* This assumes that all registers are saved into the jmp_buf */
- setjmp (scm_save_regs_gc_mark);
- scm_mark_locations ((SCM_STACKITEM *) scm_save_regs_gc_mark,
- ((size_t) sizeof scm_save_regs_gc_mark
- / sizeof (SCM_STACKITEM)));
-
- scm_mark_locations (((size_t) t->base,
- (sizet) stack_len));
-#else
- stack_len = ((SCM_STACKITEM *) t->base -
- (SCM_STACKITEM *) (&t));
-
- /* Protect from the C stack. This must be the first marking
- * done because it provides information about what objects
- * are "in-use" by the C code. "in-use" objects are those
- * for which the information about length and base address must
- * remain usable. This requirement is stricter than a liveness
- * requirement -- in particular, it constrains the implementation
- * of scm_resizuve.
- */
- SCM_FLUSH_REGISTER_WINDOWS;
- /* This assumes that all registers are saved into the jmp_buf */
- setjmp (scm_save_regs_gc_mark);
- scm_mark_locations ((SCM_STACKITEM *) scm_save_regs_gc_mark,
- ((size_t) sizeof scm_save_regs_gc_mark
- / sizeof (SCM_STACKITEM)));
-
- scm_mark_locations ((SCM_STACKITEM *) &t,
- stack_len);
-#endif
- }
- else
- {
- /* Suspended thread */
-#ifdef STACK_GROWS_UP
- long stack_len = t->top - t->base;
- scm_mark_locations (t->base, stack_len);
-#else
- long stack_len = t->base - t->top;
- scm_mark_locations (t->top, stack_len);
-#endif
- scm_mark_locations ((SCM_STACKITEM *) t->regs,
- ((size_t) sizeof(t->regs)
- / sizeof (SCM_STACKITEM)));
- }
- }
-}
-
-/*** Select */
-
-int
-scm_internal_select (int nfds,
- SELECT_TYPE *readfds,
- SELECT_TYPE *writefds,
- SELECT_TYPE *exceptfds,
- struct timeval *timeout)
-{
- int res, eno;
- scm_thread *c = scm_i_leave_guile ();
- res = scm_i_plugin_select (nfds, readfds, writefds, exceptfds, timeout);
- eno = errno;
- scm_i_enter_guile (c);
- SCM_ASYNC_TICK;
- errno = eno;
- return res;
-}
-
-/* Low-level C API */
-
-SCM
-scm_spawn_thread (scm_t_catch_body body, void *body_data,
- scm_t_catch_handler handler, void *handler_data)
-{
- return create_thread (body, body_data, handler, handler_data, SCM_BOOL_F);
-}
-
-int
-scm_mutex_lock (scm_t_mutex *m)
-{
- scm_thread *t = scm_i_leave_guile ();
- int res = scm_i_plugin_mutex_lock (m);
- scm_i_enter_guile (t);
- return res;
-}
-
-int
-scm_cond_wait (scm_t_cond *c, scm_t_mutex *m)
-{
- scm_thread *t = scm_i_leave_guile ();
- scm_i_plugin_cond_wait (c, m);
- scm_i_enter_guile (t);
- return 0;
-}
-
-int
-scm_cond_timedwait (scm_t_cond *c, scm_t_mutex *m, const struct timespec *wt)
-{
- scm_thread *t = scm_i_leave_guile ();
- int res = scm_i_plugin_cond_timedwait (c, m, wt);
- scm_i_enter_guile (t);
- return res;
-}
-
-void
-scm_enter_guile ()
-{
- scm_i_enter_guile (SCM_CURRENT_THREAD);
-}
-
-void
-scm_leave_guile ()
-{
- scm_i_leave_guile ();
-}
-
-unsigned long
-scm_thread_usleep (unsigned long usecs)
-{
- struct timeval tv;
- tv.tv_usec = usecs % 1000000;
- tv.tv_sec = usecs / 1000000;
- scm_internal_select (0, NULL, NULL, NULL, &tv);
- return tv.tv_usec + tv.tv_sec*1000000;
-}
-
-unsigned long
-scm_thread_sleep (unsigned long secs)
-{
- struct timeval tv;
- tv.tv_usec = 0;
- tv.tv_sec = secs;
- scm_internal_select (0, NULL, NULL, NULL, &tv);
- return tv.tv_sec;
-}
-
-/*** Misc */
-
-SCM_DEFINE (scm_current_thread, "current-thread", 0, 0, 0,
- (void),
- "Return the thread that called this function.")
-#define FUNC_NAME s_scm_current_thread
-{
- return cur_thread;
-}
-#undef FUNC_NAME
-
-SCM_DEFINE (scm_all_threads, "all-threads", 0, 0, 0,
- (void),
- "Return a list of all threads.")
-#define FUNC_NAME s_scm_all_threads
-{
- return all_threads;
-}
-#undef FUNC_NAME
-
-scm_root_state *
-scm_i_thread_root (SCM thread)
-{
- return ((scm_thread *) SCM_THREAD_DATA (thread))->root;
-}
-
-SCM_DEFINE (scm_thread_exited_p, "thread-exited?", 1, 0, 0,
- (SCM thread),
- "Return @code{#t} iff @var{thread} has exited.\n")
-#define FUNC_NAME s_scm_thread_exited_p
-{
- return SCM_BOOL (scm_c_thread_exited_p (thread));
-}
-#undef FUNC_NAME
-
-int
-scm_c_thread_exited_p (SCM thread)
-#define FUNC_NAME s_scm_thread_exited_p
-{
- scm_thread *t;
- SCM_VALIDATE_THREAD (1, thread);
- t = SCM_THREAD_DATA (thread);
- return t->exited;
-}
-#undef FUNC_NAME
-
-static scm_t_cond wake_up_cond;
-int scm_i_thread_go_to_sleep;
-static scm_t_mutex gc_section_mutex;
-static scm_thread *gc_section_owner;
-static int gc_section_count = 0;
-static int threads_initialized_p = 0;
-
-void
-scm_i_thread_put_to_sleep ()
-{
- SCM_REC_CRITICAL_SECTION_START (gc_section);
- if (threads_initialized_p && gc_section_count == 1)
- {
- SCM threads;
- scm_i_plugin_mutex_lock (&thread_admin_mutex);
- threads = all_threads;
- /* Signal all threads to go to sleep */
- scm_i_thread_go_to_sleep = 1;
- for (; !SCM_NULLP (threads); threads = SCM_CDR (threads))
- if (SCM_CAR (threads) != cur_thread)
- {
- scm_thread *t = SCM_THREAD_DATA (SCM_CAR (threads));
- scm_i_plugin_mutex_lock (&t->heap_mutex);
- }
- scm_i_thread_go_to_sleep = 0;
- scm_i_plugin_mutex_unlock (&thread_admin_mutex);
- }
-}
-
-void
-scm_i_thread_invalidate_freelists ()
-{
- /* Don't need to lock thread_admin_mutex here since we are sinle threaded */
- SCM threads = all_threads;
- for (; !SCM_NULLP (threads); threads = SCM_CDR (threads))
- if (SCM_CAR (threads) != cur_thread)
- {
- scm_thread *t = SCM_THREAD_DATA (SCM_CAR (threads));
- t->clear_freelists_p = 1;
- }
-}
-
-void
-scm_i_thread_wake_up ()
-{
- if (threads_initialized_p && gc_section_count == 1)
- {
- SCM threads;
- /* Need to lock since woken threads can die and be deleted from list */
- scm_i_plugin_mutex_lock (&thread_admin_mutex);
- threads = all_threads;
- scm_i_plugin_cond_broadcast (&wake_up_cond);
- for (; !SCM_NULLP (threads); threads = SCM_CDR (threads))
- if (SCM_CAR (threads) != cur_thread)
- {
- scm_thread *t = SCM_THREAD_DATA (SCM_CAR (threads));
- scm_i_plugin_mutex_unlock (&t->heap_mutex);
- }
- scm_i_plugin_mutex_unlock (&thread_admin_mutex);
- }
- SCM_REC_CRITICAL_SECTION_END (gc_section);
-}
-
-void
-scm_i_thread_sleep_for_gc ()
-{
- scm_thread *t;
- t = suspend ();
- scm_i_plugin_cond_wait (&wake_up_cond, &t->heap_mutex);
- resume (t);
-}
-
-/* The mother of all recursive critical sections */
-scm_t_mutex scm_i_section_mutex;
-
-scm_t_mutex scm_i_critical_section_mutex;
-scm_t_mutex scm_i_defer_mutex;
-int scm_i_defer_count = 0;
-scm_thread *scm_i_defer_owner = 0;
-
-/*** Initialization */
-
-void
-scm_threads_prehistory ()
-{
- scm_thread *t;
- scm_i_plugin_mutex_init (&thread_admin_mutex, 0);
- scm_i_plugin_mutex_init (&gc_section_mutex, 0);
- scm_i_plugin_cond_init (&wake_up_cond, 0);
- scm_i_plugin_mutex_init (&scm_i_critical_section_mutex, 0);
- thread_count = 1;
- scm_i_plugin_key_create (&scm_i_thread_key, 0);
- scm_i_plugin_key_create (&scm_i_root_state_key, 0);
- scm_i_plugin_mutex_init (&scm_i_defer_mutex, 0);
- scm_i_plugin_mutex_init (&scm_i_section_mutex, 0);
- /* Allocate a fake thread object to be used during bootup. */
- t = malloc (sizeof (scm_thread));
- t->base = NULL;
- t->clear_freelists_p = 0;
- scm_setspecific (scm_i_thread_key, t);
-}
-
-scm_t_bits scm_tc16_thread;
-scm_t_bits scm_tc16_mutex;
-scm_t_bits scm_tc16_fair_mutex;
-scm_t_bits scm_tc16_condvar;
-scm_t_bits scm_tc16_fair_condvar;
-
-void
-scm_init_threads (SCM_STACKITEM *base)
-{
- SCM thread;
- scm_tc16_thread = scm_make_smob_type ("thread", sizeof (scm_thread));
- scm_tc16_mutex = scm_make_smob_type ("mutex", sizeof (scm_t_mutex));
- scm_tc16_fair_mutex = scm_make_smob_type ("fair-mutex",
- sizeof (fair_mutex));
- scm_tc16_condvar = scm_make_smob_type ("condition-variable",
- sizeof (scm_t_cond));
- scm_tc16_fair_condvar = scm_make_smob_type ("fair-condition-variable",
- sizeof (fair_cond));
-
- thread = make_thread (SCM_BOOL_F);
- /* Replace initial fake thread with a real thread object */
- free (SCM_CURRENT_THREAD);
- scm_setspecific (scm_i_thread_key, SCM_THREAD_DATA (thread));
- scm_i_enter_guile (SCM_CURRENT_THREAD);
-
- /* root is set later from init.c */
- init_thread_creatant (thread, base);
- thread_count = 1;
- scm_gc_register_root (&all_threads);
- all_threads = scm_cons (thread, SCM_EOL);
-
- scm_set_smob_mark (scm_tc16_thread, thread_mark);
- scm_set_smob_print (scm_tc16_thread, thread_print);
- scm_set_smob_free (scm_tc16_thread, thread_free);
-
- scm_set_smob_mark (scm_tc16_fair_mutex, fair_mutex_mark);
-
- scm_set_smob_mark (scm_tc16_fair_condvar, fair_cond_mark);
-
- threads_initialized_p = 1;
-}
-
-void
-scm_init_thread_procs ()
-{
-#include "libguile/threads.x"
-}
-
-/* XXX */
-
-void
-scm_init_iselect ()
-{
-}
-
-/*
- Local Variables:
- c-file-style: "gnu"
- End:
-*/
+/* Copyright (C) 1995, 1996, 1997, 1998, 2000, 2001, 2002, 2003, 2004,
+ * 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013
+ * Free Software Foundation, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+
+\f
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libguile/bdw-gc.h"
+#include "libguile/_scm.h"
+
+#include <stdlib.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <stdio.h>
+
+#ifdef HAVE_STRING_H
+#include <string.h> /* for memset used by FD_ZERO on Solaris 10 */
+#endif
+
+#if HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+
+#if HAVE_PTHREAD_NP_H
+# include <pthread_np.h>
+#endif
+
+#include <sys/select.h>
+
+#include <assert.h>
+#include <fcntl.h>
+#include <nproc.h>
+
+#include "libguile/validate.h"
+#include "libguile/root.h"
+#include "libguile/eval.h"
+#include "libguile/async.h"
+#include "libguile/ports.h"
+#include "libguile/threads.h"
+#include "libguile/dynwind.h"
+#include "libguile/iselect.h"
+#include "libguile/fluids.h"
+#include "libguile/continuations.h"
+#include "libguile/gc.h"
+#include "libguile/init.h"
+#include "libguile/scmsigs.h"
+#include "libguile/strings.h"
+#include "libguile/weaks.h"
+
+#include <full-read.h>
+
+
+\f
+
+/* First some libgc shims. */
+
+/* Make sure GC_fn_type is defined; it is missing from the public
+ headers of GC 7.1 and earlier. */
+#ifndef HAVE_GC_FN_TYPE
+typedef void * (* GC_fn_type) (void *);
+#endif
+
+
+#ifndef GC_SUCCESS
+#define GC_SUCCESS 0
+#endif
+
+#ifndef GC_UNIMPLEMENTED
+#define GC_UNIMPLEMENTED 3
+#endif
+
+/* Likewise struct GC_stack_base is missing before 7.1. */
+#ifndef HAVE_GC_STACK_BASE
+struct GC_stack_base {
+ void * mem_base; /* Base of memory stack. */
+#ifdef __ia64__
+ void * reg_base; /* Base of separate register stack. */
+#endif
+};
+
+static int
+GC_register_my_thread (struct GC_stack_base *stack_base)
+{
+ return GC_UNIMPLEMENTED;
+}
+
+static void
+GC_unregister_my_thread ()
+{
+}
+
+#if !SCM_USE_PTHREAD_THREADS
+/* No threads; we can just use GC_stackbottom. */
+static void *
+get_thread_stack_base ()
+{
+ return GC_stackbottom;
+}
+
+#elif defined HAVE_PTHREAD_ATTR_GETSTACK && defined HAVE_PTHREAD_GETATTR_NP \
+ && defined PTHREAD_ATTR_GETSTACK_WORKS
+/* This method for GNU/Linux and perhaps some other systems.
+ It's not for MacOS X or Solaris 10, since pthread_getattr_np is not
+ available on them. */
+static void *
+get_thread_stack_base ()
+{
+ pthread_attr_t attr;
+ void *start, *end;
+ size_t size;
+
+ pthread_getattr_np (pthread_self (), &attr);
+ pthread_attr_getstack (&attr, &start, &size);
+ end = (char *)start + size;
+
+#if SCM_STACK_GROWS_UP
+ return start;
+#else
+ return end;
+#endif
+}
+
+#elif defined HAVE_PTHREAD_GET_STACKADDR_NP
+/* This method for MacOS X.
+ It'd be nice if there was some documentation on pthread_get_stackaddr_np,
+ but as of 2006 there's nothing obvious at apple.com. */
+static void *
+get_thread_stack_base ()
+{
+ return pthread_get_stackaddr_np (pthread_self ());
+}
+
+#elif HAVE_PTHREAD_ATTR_GET_NP
+/* This one is for FreeBSD 9. */
+static void *
+get_thread_stack_base ()
+{
+ pthread_attr_t attr;
+ void *start, *end;
+ size_t size;
+
+ pthread_attr_init (&attr);
+ pthread_attr_get_np (pthread_self (), &attr);
+ pthread_attr_getstack (&attr, &start, &size);
+ pthread_attr_destroy (&attr);
+
+ end = (char *)start + size;
+
+#if SCM_STACK_GROWS_UP
+ return start;
+#else
+ return end;
+#endif
+}
+
+#else
+#error Threads enabled with old BDW-GC, but missing get_thread_stack_base impl. Please upgrade to libgc >= 7.1.
+#endif
+
+static int
+GC_get_stack_base (struct GC_stack_base *stack_base)
+{
+ stack_base->mem_base = get_thread_stack_base ();
+#ifdef __ia64__
+ /* Calculate and store off the base of this thread's register
+ backing store (RBS). Unfortunately our implementation(s) of
+ scm_ia64_register_backing_store_base are only reliable for the
+ main thread. For other threads, therefore, find out the current
+ top of the RBS, and use that as a maximum. */
+ stack_base->reg_base = scm_ia64_register_backing_store_base ();
+ {
+ ucontext_t ctx;
+ void *bsp;
+ getcontext (&ctx);
+ bsp = scm_ia64_ar_bsp (&ctx);
+ if (stack_base->reg_base > bsp)
+ stack_base->reg_base = bsp;
+ }
+#endif
+ return GC_SUCCESS;
+}
+
+static void *
+GC_call_with_stack_base(void * (*fn) (struct GC_stack_base*, void*), void *arg)
+{
+ struct GC_stack_base stack_base;
+
+ stack_base.mem_base = (void*)&stack_base;
+#ifdef __ia64__
+ /* FIXME: Untested. */
+ {
+ ucontext_t ctx;
+ getcontext (&ctx);
+ stack_base.reg_base = scm_ia64_ar_bsp (&ctx);
+ }
+#endif
+
+ return fn (&stack_base, arg);
+}
+#endif /* HAVE_GC_STACK_BASE */
+
+
+/* Now define with_gc_active and with_gc_inactive. */
+
+#if (defined(HAVE_GC_DO_BLOCKING) && defined (HAVE_DECL_GC_DO_BLOCKING) && defined (HAVE_GC_CALL_WITH_GC_ACTIVE))
+
+/* We have a sufficiently new libgc (7.2 or newer). */
+
+static void*
+with_gc_inactive (GC_fn_type func, void *data)
+{
+ return GC_do_blocking (func, data);
+}
+
+static void*
+with_gc_active (GC_fn_type func, void *data)
+{
+ return GC_call_with_gc_active (func, data);
+}
+
+#else
+
+/* libgc not new enough, so never actually deactivate GC.
+
+ Note that though GC 7.1 does have a GC_do_blocking, it doesn't have
+ GC_call_with_gc_active. */
+
+static void*
+with_gc_inactive (GC_fn_type func, void *data)
+{
+ return func (data);
+}
+
+static void*
+with_gc_active (GC_fn_type func, void *data)
+{
+ return func (data);
+}
+
+#endif /* HAVE_GC_DO_BLOCKING */
+
+
+\f
+static void
+to_timespec (SCM t, scm_t_timespec *waittime)
+{
+ if (scm_is_pair (t))
+ {
+ waittime->tv_sec = scm_to_ulong (SCM_CAR (t));
+ waittime->tv_nsec = scm_to_ulong (SCM_CDR (t)) * 1000;
+ }
+ else
+ {
+ double time = scm_to_double (t);
+ double sec = scm_c_truncate (time);
+
+ waittime->tv_sec = (long) sec;
+ waittime->tv_nsec = (long) ((time - sec) * 1000000000);
+ }
+}
+
+\f
+/*** Queues */
+
+/* Note: We annotate with "GC-robust" assignments whose purpose is to avoid
+ the risk of false references leading to unbounded retained space as
+ described in "Bounding Space Usage of Conservative Garbage Collectors",
+ H.J. Boehm, 2001. */
+
+/* Make an empty queue data structure.
+ */
+static SCM
+make_queue ()
+{
+ return scm_cons (SCM_EOL, SCM_EOL);
+}
+
+/* Put T at the back of Q and return a handle that can be used with
+ remqueue to remove T from Q again.
+ */
+static SCM
+enqueue (SCM q, SCM t)
+{
+ SCM c = scm_cons (t, SCM_EOL);
+ SCM_CRITICAL_SECTION_START;
+ if (scm_is_null (SCM_CDR (q)))
+ SCM_SETCDR (q, c);
+ else
+ SCM_SETCDR (SCM_CAR (q), c);
+ SCM_SETCAR (q, c);
+ SCM_CRITICAL_SECTION_END;
+ return c;
+}
+
+/* Remove the element that the handle C refers to from the queue Q. C
+ must have been returned from a call to enqueue. The return value
+ is zero when the element referred to by C has already been removed.
+ Otherwise, 1 is returned.
+*/
+static int
+remqueue (SCM q, SCM c)
+{
+ SCM p, prev = q;
+ SCM_CRITICAL_SECTION_START;
+ for (p = SCM_CDR (q); !scm_is_null (p); p = SCM_CDR (p))
+ {
+ if (scm_is_eq (p, c))
+ {
+ if (scm_is_eq (c, SCM_CAR (q)))
+ SCM_SETCAR (q, SCM_CDR (c));
+ SCM_SETCDR (prev, SCM_CDR (c));
+
+ /* GC-robust */
+ SCM_SETCDR (c, SCM_EOL);
+
+ SCM_CRITICAL_SECTION_END;
+ return 1;
+ }
+ prev = p;
+ }
+ SCM_CRITICAL_SECTION_END;
+ return 0;
+}
+
+/* Remove the front-most element from the queue Q and return it.
+ Return SCM_BOOL_F when Q is empty.
+*/
+static SCM
+dequeue (SCM q)
+{
+ SCM c;
+ SCM_CRITICAL_SECTION_START;
+ c = SCM_CDR (q);
+ if (scm_is_null (c))
+ {
+ SCM_CRITICAL_SECTION_END;
+ return SCM_BOOL_F;
+ }
+ else
+ {
+ SCM_SETCDR (q, SCM_CDR (c));
+ if (scm_is_null (SCM_CDR (q)))
+ SCM_SETCAR (q, SCM_EOL);
+ SCM_CRITICAL_SECTION_END;
+
+ /* GC-robust */
+ SCM_SETCDR (c, SCM_EOL);
+
+ return SCM_CAR (c);
+ }
+}
+
+/*** Thread smob routines */
+
+
+static int
+thread_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
+{
+ /* On a Gnu system pthread_t is an unsigned long, but on mingw it's a
+ struct. A cast like "(unsigned long) t->pthread" is a syntax error in
+ the struct case, hence we go via a union, and extract according to the
+ size of pthread_t. */
+ union {
+ scm_i_pthread_t p;
+ unsigned short us;
+ unsigned int ui;
+ unsigned long ul;
+ scm_t_uintmax um;
+ } u;
+ scm_i_thread *t = SCM_I_THREAD_DATA (exp);
+ scm_i_pthread_t p = t->pthread;
+ scm_t_uintmax id;
+ u.p = p;
+ if (sizeof (p) == sizeof (unsigned short))
+ id = u.us;
+ else if (sizeof (p) == sizeof (unsigned int))
+ id = u.ui;
+ else if (sizeof (p) == sizeof (unsigned long))
+ id = u.ul;
+ else
+ id = u.um;
+
+ scm_puts ("#<thread ", port);
+ scm_uintprint (id, 10, port);
+ scm_puts (" (", port);
+ scm_uintprint ((scm_t_bits)t, 16, port);
+ scm_puts (")>", port);
+ return 1;
+}
+
+\f
+/*** Blocking on queues. */
+
+/* See also scm_i_queue_async_cell for how such a block is
+ interrputed.
+*/
+
+/* Put the current thread on QUEUE and go to sleep, waiting for it to
+ be woken up by a call to 'unblock_from_queue', or to be
+ interrupted. Upon return of this function, the current thread is
+ no longer on QUEUE, even when the sleep has been interrupted.
+
+ The caller of block_self must hold MUTEX. It will be atomically
+ unlocked while sleeping, just as with scm_i_pthread_cond_wait.
+
+ SLEEP_OBJECT is an arbitrary SCM value that is kept alive as long
+ as MUTEX is needed.
+
+ When WAITTIME is not NULL, the sleep will be aborted at that time.
+
+ The return value of block_self is an errno value. It will be zero
+ when the sleep has been successfully completed by a call to
+ unblock_from_queue, EINTR when it has been interrupted by the
+ delivery of a system async, and ETIMEDOUT when the timeout has
+ expired.
+
+ The system asyncs themselves are not executed by block_self.
+*/
+static int
+block_self (SCM queue, SCM sleep_object, scm_i_pthread_mutex_t *mutex,
+ const scm_t_timespec *waittime)
+{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+ SCM q_handle;
+ int err;
+
+ if (scm_i_setup_sleep (t, sleep_object, mutex, -1))
+ err = EINTR;
+ else
+ {
+ t->block_asyncs++;
+ q_handle = enqueue (queue, t->handle);
+ if (waittime == NULL)
+ err = scm_i_scm_pthread_cond_wait (&t->sleep_cond, mutex);
+ else
+ err = scm_i_scm_pthread_cond_timedwait (&t->sleep_cond, mutex, waittime);
+
+ /* When we are still on QUEUE, we have been interrupted. We
+ report this only when no other error (such as a timeout) has
+ happened above.
+ */
+ if (remqueue (queue, q_handle) && err == 0)
+ err = EINTR;
+ t->block_asyncs--;
+ scm_i_reset_sleep (t);
+ }
+
+ return err;
+}
+
+/* Wake up the first thread on QUEUE, if any. The awoken thread is
+ returned, or #f if the queue was empty.
+ */
+static SCM
+unblock_from_queue (SCM queue)
+{
+ SCM thread = dequeue (queue);
+ if (scm_is_true (thread))
+ scm_i_pthread_cond_signal (&SCM_I_THREAD_DATA(thread)->sleep_cond);
+ return thread;
+}
+
+\f
+/* Getting into and out of guile mode.
+ */
+
+/* Key used to attach a cleanup handler to a given thread. Also, if
+ thread-local storage is unavailable, this key is used to retrieve the
+ current thread with `pthread_getspecific ()'. */
+scm_i_pthread_key_t scm_i_thread_key;
+
+
+#ifdef SCM_HAVE_THREAD_STORAGE_CLASS
+
+/* When thread-local storage (TLS) is available, a pointer to the
+ current-thread object is kept in TLS. Note that storing the thread-object
+ itself in TLS (rather than a pointer to some malloc'd memory) is not
+ possible since thread objects may live longer than the actual thread they
+ represent. */
+SCM_THREAD_LOCAL scm_i_thread *scm_i_current_thread = NULL;
+
+#endif /* SCM_HAVE_THREAD_STORAGE_CLASS */
+
+
+static scm_i_pthread_mutex_t thread_admin_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER;
+static scm_i_thread *all_threads = NULL;
+static int thread_count;
+
+static SCM scm_i_default_dynamic_state;
+
+/* Run when a fluid is collected. */
+void
+scm_i_reset_fluid (size_t n)
+{
+ scm_i_thread *t;
+
+ scm_i_pthread_mutex_lock (&thread_admin_mutex);
+ for (t = all_threads; t; t = t->next_thread)
+ if (SCM_I_DYNAMIC_STATE_P (t->dynamic_state))
+ {
+ SCM v = SCM_I_DYNAMIC_STATE_FLUIDS (t->dynamic_state);
+
+ if (n < SCM_SIMPLE_VECTOR_LENGTH (v))
+ SCM_SIMPLE_VECTOR_SET (v, n, SCM_UNDEFINED);
+ }
+ scm_i_pthread_mutex_unlock (&thread_admin_mutex);
+}
+
+/* Perform first stage of thread initialisation, in non-guile mode.
+ */
+static void
+guilify_self_1 (struct GC_stack_base *base)
+{
+ scm_i_thread t;
+
+ /* We must arrange for SCM_I_CURRENT_THREAD to point to a valid value
+ before allocating anything in this thread, because allocation could
+ cause GC to run, and GC could cause finalizers, which could invoke
+ Scheme functions, which need the current thread to be set. */
+
+ t.pthread = scm_i_pthread_self ();
+ t.handle = SCM_BOOL_F;
+ t.result = SCM_BOOL_F;
+ t.cleanup_handler = SCM_BOOL_F;
+ t.mutexes = SCM_EOL;
+ t.held_mutex = NULL;
+ t.join_queue = SCM_EOL;
+ t.dynamic_state = SCM_BOOL_F;
+ t.dynwinds = SCM_EOL;
+ t.active_asyncs = SCM_EOL;
+ t.block_asyncs = 1;
+ t.pending_asyncs = 1;
+ t.critical_section_level = 0;
+ t.base = base->mem_base;
+#ifdef __ia64__
+ t.register_backing_store_base = base->reg_base;
+#endif
+ t.continuation_root = SCM_EOL;
+ t.continuation_base = t.base;
+ scm_i_pthread_cond_init (&t.sleep_cond, NULL);
+ t.sleep_mutex = NULL;
+ t.sleep_object = SCM_BOOL_F;
+ t.sleep_fd = -1;
+
+ if (pipe2 (t.sleep_pipe, O_CLOEXEC) != 0)
+ /* FIXME: Error conditions during the initialization phase are handled
+ gracelessly since public functions such as `scm_init_guile ()'
+ currently have type `void'. */
+ abort ();
+
+ scm_i_pthread_mutex_init (&t.admin_mutex, NULL);
+ t.current_mark_stack_ptr = NULL;
+ t.current_mark_stack_limit = NULL;
+ t.canceled = 0;
+ t.exited = 0;
+ t.guile_mode = 0;
+
+ /* The switcheroo. */
+ {
+ scm_i_thread *t_ptr = &t;
+
+ GC_disable ();
+ t_ptr = GC_malloc (sizeof (scm_i_thread));
+ memcpy (t_ptr, &t, sizeof t);
+
+ scm_i_pthread_setspecific (scm_i_thread_key, t_ptr);
+
+#ifdef SCM_HAVE_THREAD_STORAGE_CLASS
+ /* Cache the current thread in TLS for faster lookup. */
+ scm_i_current_thread = t_ptr;
+#endif
+
+ scm_i_pthread_mutex_lock (&thread_admin_mutex);
+ t_ptr->next_thread = all_threads;
+ all_threads = t_ptr;
+ thread_count++;
+ scm_i_pthread_mutex_unlock (&thread_admin_mutex);
+
+ GC_enable ();
+ }
+}
+
+/* Perform second stage of thread initialisation, in guile mode.
+ */
+static void
+guilify_self_2 (SCM parent)
+{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
+ t->guile_mode = 1;
+
+ SCM_NEWSMOB (t->handle, scm_tc16_thread, t);
+
+ t->continuation_root = scm_cons (t->handle, SCM_EOL);
+ t->continuation_base = t->base;
+ t->vm = SCM_BOOL_F;
+
+ if (scm_is_true (parent))
+ t->dynamic_state = scm_make_dynamic_state (parent);
+ else
+ t->dynamic_state = scm_i_make_initial_dynamic_state ();
+
+ t->join_queue = make_queue ();
+ t->block_asyncs = 0;
+
+ /* See note in finalizers.c:queue_finalizer_async(). */
+ GC_invoke_finalizers ();
+}
+
+\f
+/*** Fat mutexes */
+
+/* We implement our own mutex type since we want them to be 'fair', we
+ want to do fancy things while waiting for them (like running
+ asyncs) and we might want to add things that are nice for
+ debugging.
+*/
+
+typedef struct {
+ scm_i_pthread_mutex_t lock;
+ SCM owner;
+ int level; /* how much the owner owns us. <= 1 for non-recursive mutexes */
+
+ int recursive; /* allow recursive locking? */
+ int unchecked_unlock; /* is it an error to unlock an unlocked mutex? */
+ int allow_external_unlock; /* is it an error to unlock a mutex that is not
+ owned by the current thread? */
+
+ SCM waiting; /* the threads waiting for this mutex. */
+} fat_mutex;
+
+#define SCM_MUTEXP(x) SCM_SMOB_PREDICATE (scm_tc16_mutex, x)
+#define SCM_MUTEX_DATA(x) ((fat_mutex *) SCM_SMOB_DATA (x))
+
+static SCM
+call_cleanup (void *data)
+{
+ SCM *proc_p = data;
+ return scm_call_0 (*proc_p);
+}
+
+/* Perform thread tear-down, in guile mode.
+ */
+static void *
+do_thread_exit (void *v)
+{
+ scm_i_thread *t = (scm_i_thread *) v;
+
+ /* Ensure the signal handling thread has been launched, because we might be
+ shutting it down. This needs to be done in Guile mode. */
+ scm_i_ensure_signal_delivery_thread ();
+
+ if (!scm_is_false (t->cleanup_handler))
+ {
+ SCM ptr = t->cleanup_handler;
+
+ t->cleanup_handler = SCM_BOOL_F;
+ t->result = scm_internal_catch (SCM_BOOL_T,
+ call_cleanup, &ptr,
+ scm_handle_by_message_noexit, NULL);
+ }
+
+ scm_i_scm_pthread_mutex_lock (&t->admin_mutex);
+
+ t->exited = 1;
+ close (t->sleep_pipe[0]);
+ close (t->sleep_pipe[1]);
+ while (scm_is_true (unblock_from_queue (t->join_queue)))
+ ;
+
+ while (!scm_is_null (t->mutexes))
+ {
+ SCM mutex = SCM_WEAK_PAIR_CAR (t->mutexes);
+
+ if (!SCM_UNBNDP (mutex))
+ {
+ fat_mutex *m = SCM_MUTEX_DATA (mutex);
+
+ scm_i_pthread_mutex_lock (&m->lock);
+
+ /* Check whether T owns MUTEX. This is usually the case, unless
+ T abandoned MUTEX; in that case, T is no longer its owner (see
+ `fat_mutex_lock') but MUTEX is still in `t->mutexes'. */
+ if (scm_is_eq (m->owner, t->handle))
+ unblock_from_queue (m->waiting);
+
+ scm_i_pthread_mutex_unlock (&m->lock);
+ }
+
+ t->mutexes = SCM_WEAK_PAIR_CDR (t->mutexes);
+ }
+
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+
+ return NULL;
+}
+
+static void *
+do_thread_exit_trampoline (struct GC_stack_base *sb, void *v)
+{
+ /* Won't hurt if we are already registered. */
+#if SCM_USE_PTHREAD_THREADS
+ GC_register_my_thread (sb);
+#endif
+
+ return scm_with_guile (do_thread_exit, v);
+}
+
+static void
+on_thread_exit (void *v)
+{
+ /* This handler is executed in non-guile mode. */
+ scm_i_thread *t = (scm_i_thread *) v, **tp;
+
+ /* If we were canceled, we were unable to clear `t->guile_mode', so do
+ it here. */
+ t->guile_mode = 0;
+
+ /* If this thread was cancelled while doing a cond wait, it will
+ still have a mutex locked, so we unlock it here. */
+ if (t->held_mutex)
+ {
+ scm_i_pthread_mutex_unlock (t->held_mutex);
+ t->held_mutex = NULL;
+ }
+
+ /* Reinstate the current thread for purposes of scm_with_guile
+ guile-mode cleanup handlers. Only really needed in the non-TLS
+ case but it doesn't hurt to be consistent. */
+ scm_i_pthread_setspecific (scm_i_thread_key, t);
+
+ /* Scheme-level thread finalizers and other cleanup needs to happen in
+ guile mode. */
+ GC_call_with_stack_base (do_thread_exit_trampoline, t);
+
+ /* Removing ourself from the list of all threads needs to happen in
+ non-guile mode since all SCM values on our stack become
+ unprotected once we are no longer in the list. */
+ scm_i_pthread_mutex_lock (&thread_admin_mutex);
+ for (tp = &all_threads; *tp; tp = &(*tp)->next_thread)
+ if (*tp == t)
+ {
+ *tp = t->next_thread;
+
+ /* GC-robust */
+ t->next_thread = NULL;
+
+ break;
+ }
+ thread_count--;
+
+ /* If there's only one other thread, it could be the signal delivery
+ thread, so we need to notify it to shut down by closing its read pipe.
+ If it's not the signal delivery thread, then closing the read pipe isn't
+ going to hurt. */
+ if (thread_count <= 1)
+ scm_i_close_signal_pipe ();
+
+ scm_i_pthread_mutex_unlock (&thread_admin_mutex);
+
+ scm_i_pthread_setspecific (scm_i_thread_key, NULL);
+
+#if SCM_USE_PTHREAD_THREADS
+ GC_unregister_my_thread ();
+#endif
+}
+
+static scm_i_pthread_once_t init_thread_key_once = SCM_I_PTHREAD_ONCE_INIT;
+
+static void
+init_thread_key (void)
+{
+ scm_i_pthread_key_create (&scm_i_thread_key, on_thread_exit);
+}
+
+/* Perform any initializations necessary to make the current thread
+ known to Guile (via SCM_I_CURRENT_THREAD), initializing Guile itself,
+ if necessary.
+
+ BASE is the stack base to use with GC.
+
+ PARENT is the dynamic state to use as the parent, ot SCM_BOOL_F in
+ which case the default dynamic state is used.
+
+ Returns zero when the thread was known to guile already; otherwise
+ return 1.
+
+ Note that it could be the case that the thread was known
+ to Guile, but not in guile mode (because we are within a
+ scm_without_guile call). Check SCM_I_CURRENT_THREAD->guile_mode to
+ be sure. New threads are put into guile mode implicitly. */
+
+static int
+scm_i_init_thread_for_guile (struct GC_stack_base *base, SCM parent)
+{
+ scm_i_pthread_once (&init_thread_key_once, init_thread_key);
+
+ if (SCM_I_CURRENT_THREAD)
+ {
+ /* Thread is already known to Guile.
+ */
+ return 0;
+ }
+ else
+ {
+ /* This thread has not been guilified yet.
+ */
+
+ scm_i_pthread_mutex_lock (&scm_i_init_mutex);
+ if (scm_initialized_p == 0)
+ {
+ /* First thread ever to enter Guile. Run the full
+ initialization.
+ */
+ scm_i_init_guile (base);
+
+#if defined (HAVE_GC_ALLOW_REGISTER_THREADS) && SCM_USE_PTHREAD_THREADS
+ /* Allow other threads to come in later. */
+ GC_allow_register_threads ();
+#endif
+
+ scm_i_pthread_mutex_unlock (&scm_i_init_mutex);
+ }
+ else
+ {
+ /* Guile is already initialized, but this thread enters it for
+ the first time. Only initialize this thread.
+ */
+ scm_i_pthread_mutex_unlock (&scm_i_init_mutex);
+
+ /* Register this thread with libgc. */
+#if SCM_USE_PTHREAD_THREADS
+ GC_register_my_thread (base);
+#endif
+
+ guilify_self_1 (base);
+ guilify_self_2 (parent);
+ }
+ return 1;
+ }
+}
+
+void
+scm_init_guile ()
+{
+ struct GC_stack_base stack_base;
+
+ if (GC_get_stack_base (&stack_base) == GC_SUCCESS)
+ scm_i_init_thread_for_guile (&stack_base,
+ scm_i_default_dynamic_state);
+ else
+ {
+ fprintf (stderr, "Failed to get stack base for current thread.\n");
+ exit (EXIT_FAILURE);
+ }
+}
+
+struct with_guile_args
+{
+ GC_fn_type func;
+ void *data;
+ SCM parent;
+};
+
+static void *
+with_guile_trampoline (void *data)
+{
+ struct with_guile_args *args = data;
+
+ return scm_c_with_continuation_barrier (args->func, args->data);
+}
+
+static void *
+with_guile_and_parent (struct GC_stack_base *base, void *data)
+{
+ void *res;
+ int new_thread;
+ scm_i_thread *t;
+ struct with_guile_args *args = data;
+
+ new_thread = scm_i_init_thread_for_guile (base, args->parent);
+ t = SCM_I_CURRENT_THREAD;
+ if (new_thread)
+ {
+ /* We are in Guile mode. */
+ assert (t->guile_mode);
+
+ res = scm_c_with_continuation_barrier (args->func, args->data);
+
+ /* Leave Guile mode. */
+ t->guile_mode = 0;
+ }
+ else if (t->guile_mode)
+ {
+ /* Already in Guile mode. */
+ res = scm_c_with_continuation_barrier (args->func, args->data);
+ }
+ else
+ {
+ /* We are not in Guile mode, either because we are not within a
+ scm_with_guile, or because we are within a scm_without_guile.
+
+ This call to scm_with_guile() could happen from anywhere on the
+ stack, and in particular lower on the stack than when it was
+ when this thread was first guilified. Thus, `base' must be
+ updated. */
+#if SCM_STACK_GROWS_UP
+ if (SCM_STACK_PTR (base->mem_base) < t->base)
+ t->base = SCM_STACK_PTR (base->mem_base);
+#else
+ if (SCM_STACK_PTR (base->mem_base) > t->base)
+ t->base = SCM_STACK_PTR (base->mem_base);
+#endif
+
+ t->guile_mode = 1;
+ res = with_gc_active (with_guile_trampoline, args);
+ t->guile_mode = 0;
+ }
+ return res;
+}
+
+static void *
+scm_i_with_guile_and_parent (void *(*func)(void *), void *data, SCM parent)
+{
+ struct with_guile_args args;
+
+ args.func = func;
+ args.data = data;
+ args.parent = parent;
+
+ return GC_call_with_stack_base (with_guile_and_parent, &args);
+}
+
+void *
+scm_with_guile (void *(*func)(void *), void *data)
+{
+ return scm_i_with_guile_and_parent (func, data,
+ scm_i_default_dynamic_state);
+}
+
+void *
+scm_without_guile (void *(*func)(void *), void *data)
+{
+ void *result;
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
+ if (t->guile_mode)
+ {
+ SCM_I_CURRENT_THREAD->guile_mode = 0;
+ result = with_gc_inactive (func, data);
+ SCM_I_CURRENT_THREAD->guile_mode = 1;
+ }
+ else
+ /* Otherwise we're not in guile mode, so nothing to do. */
+ result = func (data);
+
+ return result;
+}
+
+\f
+/*** Thread creation */
+
+typedef struct {
+ SCM parent;
+ SCM thunk;
+ SCM handler;
+ SCM thread;
+ scm_i_pthread_mutex_t mutex;
+ scm_i_pthread_cond_t cond;
+} launch_data;
+
+static void *
+really_launch (void *d)
+{
+ launch_data *data = (launch_data *)d;
+ SCM thunk = data->thunk, handler = data->handler;
+ scm_i_thread *t;
+
+ t = SCM_I_CURRENT_THREAD;
+
+ scm_i_scm_pthread_mutex_lock (&data->mutex);
+ data->thread = scm_current_thread ();
+ scm_i_pthread_cond_signal (&data->cond);
+ scm_i_pthread_mutex_unlock (&data->mutex);
+
+ if (SCM_UNBNDP (handler))
+ t->result = scm_call_0 (thunk);
+ else
+ t->result = scm_catch (SCM_BOOL_T, thunk, handler);
+
+ return 0;
+}
+
+static void *
+launch_thread (void *d)
+{
+ launch_data *data = (launch_data *)d;
+ scm_i_pthread_detach (scm_i_pthread_self ());
+ scm_i_with_guile_and_parent (really_launch, d, data->parent);
+ return NULL;
+}
+
+SCM_DEFINE (scm_call_with_new_thread, "call-with-new-thread", 1, 1, 0,
+ (SCM thunk, SCM handler),
+ "Call @code{thunk} in a new thread and with a new dynamic state,\n"
+ "returning a new thread object representing the thread. The procedure\n"
+ "@var{thunk} is called via @code{with-continuation-barrier}.\n"
+ "\n"
+ "When @var{handler} is specified, then @var{thunk} is called from\n"
+ "within a @code{catch} with tag @code{#t} that has @var{handler} as its\n"
+ "handler. This catch is established inside the continuation barrier.\n"
+ "\n"
+ "Once @var{thunk} or @var{handler} returns, the return value is made\n"
+ "the @emph{exit value} of the thread and the thread is terminated.")
+#define FUNC_NAME s_scm_call_with_new_thread
+{
+ launch_data data;
+ scm_i_pthread_t id;
+ int err;
+
+ SCM_ASSERT (scm_is_true (scm_thunk_p (thunk)), thunk, SCM_ARG1, FUNC_NAME);
+ SCM_ASSERT (SCM_UNBNDP (handler) || scm_is_true (scm_procedure_p (handler)),
+ handler, SCM_ARG2, FUNC_NAME);
+
+ GC_collect_a_little ();
+ data.parent = scm_current_dynamic_state ();
+ data.thunk = thunk;
+ data.handler = handler;
+ data.thread = SCM_BOOL_F;
+ scm_i_pthread_mutex_init (&data.mutex, NULL);
+ scm_i_pthread_cond_init (&data.cond, NULL);
+
+ scm_i_scm_pthread_mutex_lock (&data.mutex);
+ err = scm_i_pthread_create (&id, NULL, launch_thread, &data);
+ if (err)
+ {
+ scm_i_pthread_mutex_unlock (&data.mutex);
+ errno = err;
+ scm_syserror (NULL);
+ }
+
+ while (scm_is_false (data.thread))
+ scm_i_scm_pthread_cond_wait (&data.cond, &data.mutex);
+
+ scm_i_pthread_mutex_unlock (&data.mutex);
+
+ return data.thread;
+}
+#undef FUNC_NAME
+
+typedef struct {
+ SCM parent;
+ scm_t_catch_body body;
+ void *body_data;
+ scm_t_catch_handler handler;
+ void *handler_data;
+ SCM thread;
+ scm_i_pthread_mutex_t mutex;
+ scm_i_pthread_cond_t cond;
+} spawn_data;
+
+static void *
+really_spawn (void *d)
+{
+ spawn_data *data = (spawn_data *)d;
+ scm_t_catch_body body = data->body;
+ void *body_data = data->body_data;
+ scm_t_catch_handler handler = data->handler;
+ void *handler_data = data->handler_data;
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
+ scm_i_scm_pthread_mutex_lock (&data->mutex);
+ data->thread = scm_current_thread ();
+ scm_i_pthread_cond_signal (&data->cond);
+ scm_i_pthread_mutex_unlock (&data->mutex);
+
+ if (handler == NULL)
+ t->result = body (body_data);
+ else
+ t->result = scm_internal_catch (SCM_BOOL_T,
+ body, body_data,
+ handler, handler_data);
+
+ return 0;
+}
+
+static void *
+spawn_thread (void *d)
+{
+ spawn_data *data = (spawn_data *)d;
+ scm_i_pthread_detach (scm_i_pthread_self ());
+ scm_i_with_guile_and_parent (really_spawn, d, data->parent);
+ return NULL;
+}
+
+SCM
+scm_spawn_thread (scm_t_catch_body body, void *body_data,
+ scm_t_catch_handler handler, void *handler_data)
+{
+ spawn_data data;
+ scm_i_pthread_t id;
+ int err;
+
+ data.parent = scm_current_dynamic_state ();
+ data.body = body;
+ data.body_data = body_data;
+ data.handler = handler;
+ data.handler_data = handler_data;
+ data.thread = SCM_BOOL_F;
+ scm_i_pthread_mutex_init (&data.mutex, NULL);
+ scm_i_pthread_cond_init (&data.cond, NULL);
+
+ scm_i_scm_pthread_mutex_lock (&data.mutex);
+ err = scm_i_pthread_create (&id, NULL, spawn_thread, &data);
+ if (err)
+ {
+ scm_i_pthread_mutex_unlock (&data.mutex);
+ errno = err;
+ scm_syserror (NULL);
+ }
+
+ while (scm_is_false (data.thread))
+ scm_i_scm_pthread_cond_wait (&data.cond, &data.mutex);
+
+ scm_i_pthread_mutex_unlock (&data.mutex);
+
+ assert (SCM_I_IS_THREAD (data.thread));
+
+ return data.thread;
+}
+
+SCM_DEFINE (scm_yield, "yield", 0, 0, 0,
+ (),
+"Move the calling thread to the end of the scheduling queue.")
+#define FUNC_NAME s_scm_yield
+{
+ return scm_from_bool (scm_i_sched_yield ());
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_cancel_thread, "cancel-thread", 1, 0, 0,
+ (SCM thread),
+"Asynchronously force the target @var{thread} to terminate. @var{thread} "
+"cannot be the current thread, and if @var{thread} has already terminated or "
+"been signaled to terminate, this function is a no-op.")
+#define FUNC_NAME s_scm_cancel_thread
+{
+ scm_i_thread *t = NULL;
+
+ SCM_VALIDATE_THREAD (1, thread);
+ t = SCM_I_THREAD_DATA (thread);
+ scm_i_scm_pthread_mutex_lock (&t->admin_mutex);
+ if (!t->canceled)
+ {
+ t->canceled = 1;
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+ scm_i_pthread_cancel (t->pthread);
+ }
+ else
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_set_thread_cleanup_x, "set-thread-cleanup!", 2, 0, 0,
+ (SCM thread, SCM proc),
+"Set the thunk @var{proc} as the cleanup handler for the thread @var{thread}. "
+"This handler will be called when the thread exits.")
+#define FUNC_NAME s_scm_set_thread_cleanup_x
+{
+ scm_i_thread *t;
+
+ SCM_VALIDATE_THREAD (1, thread);
+ if (!scm_is_false (proc))
+ SCM_VALIDATE_THUNK (2, proc);
+
+ t = SCM_I_THREAD_DATA (thread);
+ scm_i_pthread_mutex_lock (&t->admin_mutex);
+
+ if (!(t->exited || t->canceled))
+ t->cleanup_handler = proc;
+
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_thread_cleanup, "thread-cleanup", 1, 0, 0,
+ (SCM thread),
+"Return the cleanup handler installed for the thread @var{thread}.")
+#define FUNC_NAME s_scm_thread_cleanup
+{
+ scm_i_thread *t;
+ SCM ret;
+
+ SCM_VALIDATE_THREAD (1, thread);
+
+ t = SCM_I_THREAD_DATA (thread);
+ scm_i_pthread_mutex_lock (&t->admin_mutex);
+ ret = (t->exited || t->canceled) ? SCM_BOOL_F : t->cleanup_handler;
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+
+ return ret;
+}
+#undef FUNC_NAME
+
+SCM scm_join_thread (SCM thread)
+{
+ return scm_join_thread_timed (thread, SCM_UNDEFINED, SCM_UNDEFINED);
+}
+
+SCM_DEFINE (scm_join_thread_timed, "join-thread", 1, 2, 0,
+ (SCM thread, SCM timeout, SCM timeoutval),
+"Suspend execution of the calling thread until the target @var{thread} "
+"terminates, unless the target @var{thread} has already terminated. ")
+#define FUNC_NAME s_scm_join_thread_timed
+{
+ scm_i_thread *t;
+ scm_t_timespec ctimeout, *timeout_ptr = NULL;
+ SCM res = SCM_BOOL_F;
+
+ if (! (SCM_UNBNDP (timeoutval)))
+ res = timeoutval;
+
+ SCM_VALIDATE_THREAD (1, thread);
+ if (scm_is_eq (scm_current_thread (), thread))
+ SCM_MISC_ERROR ("cannot join the current thread", SCM_EOL);
+
+ t = SCM_I_THREAD_DATA (thread);
+ scm_i_scm_pthread_mutex_lock (&t->admin_mutex);
+
+ if (! SCM_UNBNDP (timeout))
+ {
+ to_timespec (timeout, &ctimeout);
+ timeout_ptr = &ctimeout;
+ }
+
+ if (t->exited)
+ res = t->result;
+ else
+ {
+ while (1)
+ {
+ int err = block_self (t->join_queue, thread, &t->admin_mutex,
+ timeout_ptr);
+ if (err == 0)
+ {
+ if (t->exited)
+ {
+ res = t->result;
+ break;
+ }
+ }
+ else if (err == ETIMEDOUT)
+ break;
+
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+ SCM_TICK;
+ scm_i_scm_pthread_mutex_lock (&t->admin_mutex);
+
+ /* Check for exit again, since we just released and
+ reacquired the admin mutex, before the next block_self
+ call (which would block forever if t has already
+ exited). */
+ if (t->exited)
+ {
+ res = t->result;
+ break;
+ }
+ }
+ }
+
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+
+ return res;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_thread_p, "thread?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is a thread.")
+#define FUNC_NAME s_scm_thread_p
+{
+ return SCM_I_IS_THREAD(obj) ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+
+static size_t
+fat_mutex_free (SCM mx)
+{
+ fat_mutex *m = SCM_MUTEX_DATA (mx);
+ scm_i_pthread_mutex_destroy (&m->lock);
+ return 0;
+}
+
+static int
+fat_mutex_print (SCM mx, SCM port, scm_print_state *pstate SCM_UNUSED)
+{
+ fat_mutex *m = SCM_MUTEX_DATA (mx);
+ scm_puts ("#<mutex ", port);
+ scm_uintprint ((scm_t_bits)m, 16, port);
+ scm_puts (">", port);
+ return 1;
+}
+
+static SCM
+make_fat_mutex (int recursive, int unchecked_unlock, int external_unlock)
+{
+ fat_mutex *m;
+ SCM mx;
+
+ m = scm_gc_malloc (sizeof (fat_mutex), "mutex");
+ scm_i_pthread_mutex_init (&m->lock, NULL);
+ m->owner = SCM_BOOL_F;
+ m->level = 0;
+
+ m->recursive = recursive;
+ m->unchecked_unlock = unchecked_unlock;
+ m->allow_external_unlock = external_unlock;
+
+ m->waiting = SCM_EOL;
+ SCM_NEWSMOB (mx, scm_tc16_mutex, (scm_t_bits) m);
+ m->waiting = make_queue ();
+ return mx;
+}
+
+SCM scm_make_mutex (void)
+{
+ return scm_make_mutex_with_flags (SCM_EOL);
+}
+
+SCM_SYMBOL (unchecked_unlock_sym, "unchecked-unlock");
+SCM_SYMBOL (allow_external_unlock_sym, "allow-external-unlock");
+SCM_SYMBOL (recursive_sym, "recursive");
+
+SCM_DEFINE (scm_make_mutex_with_flags, "make-mutex", 0, 0, 1,
+ (SCM flags),
+ "Create a new mutex. ")
+#define FUNC_NAME s_scm_make_mutex_with_flags
+{
+ int unchecked_unlock = 0, external_unlock = 0, recursive = 0;
+
+ SCM ptr = flags;
+ while (! scm_is_null (ptr))
+ {
+ SCM flag = SCM_CAR (ptr);
+ if (scm_is_eq (flag, unchecked_unlock_sym))
+ unchecked_unlock = 1;
+ else if (scm_is_eq (flag, allow_external_unlock_sym))
+ external_unlock = 1;
+ else if (scm_is_eq (flag, recursive_sym))
+ recursive = 1;
+ else
+ SCM_MISC_ERROR ("unsupported mutex option: ~a", scm_list_1 (flag));
+ ptr = SCM_CDR (ptr);
+ }
+ return make_fat_mutex (recursive, unchecked_unlock, external_unlock);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_make_recursive_mutex, "make-recursive-mutex", 0, 0, 0,
+ (void),
+ "Create a new recursive mutex. ")
+#define FUNC_NAME s_scm_make_recursive_mutex
+{
+ return make_fat_mutex (1, 0, 0);
+}
+#undef FUNC_NAME
+
+SCM_SYMBOL (scm_abandoned_mutex_error_key, "abandoned-mutex-error");
+
+static SCM
+fat_mutex_lock (SCM mutex, scm_t_timespec *timeout, SCM owner, int *ret)
+{
+ fat_mutex *m = SCM_MUTEX_DATA (mutex);
+
+ SCM new_owner = SCM_UNBNDP (owner) ? scm_current_thread() : owner;
+ SCM err = SCM_BOOL_F;
+
+ struct timeval current_time;
+
+ scm_i_scm_pthread_mutex_lock (&m->lock);
+
+ while (1)
+ {
+ if (m->level == 0)
+ {
+ m->owner = new_owner;
+ m->level++;
+
+ if (SCM_I_IS_THREAD (new_owner))
+ {
+ scm_i_thread *t = SCM_I_THREAD_DATA (new_owner);
+
+ /* FIXME: The order in which `t->admin_mutex' and
+ `m->lock' are taken differs from that in
+ `on_thread_exit', potentially leading to deadlocks. */
+ scm_i_pthread_mutex_lock (&t->admin_mutex);
+
+ /* Only keep a weak reference to MUTEX so that it's not
+ retained when not referenced elsewhere (bug #27450).
+ The weak pair itself is eventually removed when MUTEX
+ is unlocked. Note that `t->mutexes' lists mutexes
+ currently held by T, so it should be small. */
+ t->mutexes = scm_weak_car_pair (mutex, t->mutexes);
+
+ scm_i_pthread_mutex_unlock (&t->admin_mutex);
+ }
+ *ret = 1;
+ break;
+ }
+ else if (SCM_I_IS_THREAD (m->owner) && scm_c_thread_exited_p (m->owner))
+ {
+ m->owner = new_owner;
+ err = scm_cons (scm_abandoned_mutex_error_key,
+ scm_from_locale_string ("lock obtained on abandoned "
+ "mutex"));
+ *ret = 1;
+ break;
+ }
+ else if (scm_is_eq (m->owner, new_owner))
+ {
+ if (m->recursive)
+ {
+ m->level++;
+ *ret = 1;
+ }
+ else
+ {
+ err = scm_cons (scm_misc_error_key,
+ scm_from_locale_string ("mutex already locked "
+ "by thread"));
+ *ret = 0;
+ }
+ break;
+ }
+ else
+ {
+ if (timeout != NULL)
+ {
+ gettimeofday (¤t_time, NULL);
+ if (current_time.tv_sec > timeout->tv_sec ||
+ (current_time.tv_sec == timeout->tv_sec &&
+ current_time.tv_usec * 1000 > timeout->tv_nsec))
+ {
+ *ret = 0;
+ break;
+ }
+ }
+ block_self (m->waiting, mutex, &m->lock, timeout);
+ scm_i_pthread_mutex_unlock (&m->lock);
+ SCM_TICK;
+ scm_i_scm_pthread_mutex_lock (&m->lock);
+ }
+ }
+ scm_i_pthread_mutex_unlock (&m->lock);
+ return err;
+}
+
+SCM scm_lock_mutex (SCM mx)
+{
+ return scm_lock_mutex_timed (mx, SCM_UNDEFINED, SCM_UNDEFINED);
+}
+
+SCM_DEFINE (scm_lock_mutex_timed, "lock-mutex", 1, 2, 0,
+ (SCM m, SCM timeout, SCM owner),
+ "Lock mutex @var{m}. If the mutex is already locked, the calling\n"
+ "thread blocks until the mutex becomes available. The function\n"
+ "returns when the calling thread owns the lock on @var{m}.\n"
+ "Locking a mutex that a thread already owns will succeed right\n"
+ "away and will not block the thread. That is, Guile's mutexes\n"
+ "are @emph{recursive}.")
+#define FUNC_NAME s_scm_lock_mutex_timed
+{
+ SCM exception;
+ int ret = 0;
+ scm_t_timespec cwaittime, *waittime = NULL;
+
+ SCM_VALIDATE_MUTEX (1, m);
+
+ if (! SCM_UNBNDP (timeout) && ! scm_is_false (timeout))
+ {
+ to_timespec (timeout, &cwaittime);
+ waittime = &cwaittime;
+ }
+
+ if (!SCM_UNBNDP (owner) && !scm_is_false (owner))
+ SCM_VALIDATE_THREAD (3, owner);
+
+ exception = fat_mutex_lock (m, waittime, owner, &ret);
+ if (!scm_is_false (exception))
+ scm_ithrow (SCM_CAR (exception), scm_list_1 (SCM_CDR (exception)), 1);
+ return ret ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+static void
+lock_mutex_return_void (SCM mx)
+{
+ (void) scm_lock_mutex (mx);
+}
+
+static void
+unlock_mutex_return_void (SCM mx)
+{
+ (void) scm_unlock_mutex (mx);
+}
+
+void
+scm_dynwind_lock_mutex (SCM mutex)
+{
+ scm_dynwind_unwind_handler_with_scm (unlock_mutex_return_void, mutex,
+ SCM_F_WIND_EXPLICITLY);
+ scm_dynwind_rewind_handler_with_scm (lock_mutex_return_void, mutex,
+ SCM_F_WIND_EXPLICITLY);
+}
+
+SCM_DEFINE (scm_try_mutex, "try-mutex", 1, 0, 0,
+ (SCM mutex),
+"Try to lock @var{mutex}. If the mutex is already locked by someone "
+"else, return @code{#f}. Else lock the mutex and return @code{#t}. ")
+#define FUNC_NAME s_scm_try_mutex
+{
+ SCM exception;
+ int ret = 0;
+ scm_t_timespec cwaittime, *waittime = NULL;
+
+ SCM_VALIDATE_MUTEX (1, mutex);
+
+ to_timespec (scm_from_int(0), &cwaittime);
+ waittime = &cwaittime;
+
+ exception = fat_mutex_lock (mutex, waittime, SCM_UNDEFINED, &ret);
+ if (!scm_is_false (exception))
+ scm_ithrow (SCM_CAR (exception), scm_list_1 (SCM_CDR (exception)), 1);
+ return ret ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+/*** Fat condition variables */
+
+typedef struct {
+ scm_i_pthread_mutex_t lock;
+ SCM waiting; /* the threads waiting for this condition. */
+} fat_cond;
+
+#define SCM_CONDVARP(x) SCM_SMOB_PREDICATE (scm_tc16_condvar, x)
+#define SCM_CONDVAR_DATA(x) ((fat_cond *) SCM_SMOB_DATA (x))
+
+static int
+fat_mutex_unlock (SCM mutex, SCM cond,
+ const scm_t_timespec *waittime, int relock)
+{
+ SCM owner;
+ fat_mutex *m = SCM_MUTEX_DATA (mutex);
+ fat_cond *c = NULL;
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+ int err = 0, ret = 0;
+
+ scm_i_scm_pthread_mutex_lock (&m->lock);
+
+ owner = m->owner;
+
+ if (!scm_is_eq (owner, t->handle))
+ {
+ if (m->level == 0)
+ {
+ if (!m->unchecked_unlock)
+ {
+ scm_i_pthread_mutex_unlock (&m->lock);
+ scm_misc_error (NULL, "mutex not locked", SCM_EOL);
+ }
+ owner = t->handle;
+ }
+ else if (!m->allow_external_unlock)
+ {
+ scm_i_pthread_mutex_unlock (&m->lock);
+ scm_misc_error (NULL, "mutex not locked by current thread", SCM_EOL);
+ }
+ }
+
+ if (! (SCM_UNBNDP (cond)))
+ {
+ c = SCM_CONDVAR_DATA (cond);
+ while (1)
+ {
+ int brk = 0;
+
+ if (m->level > 0)
+ m->level--;
+ if (m->level == 0)
+ {
+ /* Change the owner of MUTEX. */
+ t->mutexes = scm_delq_x (mutex, t->mutexes);
+ m->owner = unblock_from_queue (m->waiting);
+ }
+
+ t->block_asyncs++;
+
+ err = block_self (c->waiting, cond, &m->lock, waittime);
+ scm_i_pthread_mutex_unlock (&m->lock);
+
+ if (err == 0)
+ {
+ ret = 1;
+ brk = 1;
+ }
+ else if (err == ETIMEDOUT)
+ {
+ ret = 0;
+ brk = 1;
+ }
+ else if (err != EINTR)
+ {
+ errno = err;
+ scm_syserror (NULL);
+ }
+
+ if (brk)
+ {
+ if (relock)
+ scm_lock_mutex_timed (mutex, SCM_UNDEFINED, owner);
+ t->block_asyncs--;
+ break;
+ }
+
+ t->block_asyncs--;
+ scm_async_click ();
+
+ scm_remember_upto_here_2 (cond, mutex);
+
+ scm_i_scm_pthread_mutex_lock (&m->lock);
+ }
+ }
+ else
+ {
+ if (m->level > 0)
+ m->level--;
+ if (m->level == 0)
+ {
+ /* Change the owner of MUTEX. */
+ t->mutexes = scm_delq_x (mutex, t->mutexes);
+ m->owner = unblock_from_queue (m->waiting);
+ }
+
+ scm_i_pthread_mutex_unlock (&m->lock);
+ ret = 1;
+ }
+
+ return ret;
+}
+
+SCM scm_unlock_mutex (SCM mx)
+{
+ return scm_unlock_mutex_timed (mx, SCM_UNDEFINED, SCM_UNDEFINED);
+}
+
+SCM_DEFINE (scm_unlock_mutex_timed, "unlock-mutex", 1, 2, 0,
+ (SCM mx, SCM cond, SCM timeout),
+"Unlocks @var{mutex} if the calling thread owns the lock on "
+"@var{mutex}. Calling unlock-mutex on a mutex not owned by the current "
+"thread results in undefined behaviour. Once a mutex has been unlocked, "
+"one thread blocked on @var{mutex} is awakened and grabs the mutex "
+"lock. Every call to @code{lock-mutex} by this thread must be matched "
+"with a call to @code{unlock-mutex}. Only the last call to "
+"@code{unlock-mutex} will actually unlock the mutex. ")
+#define FUNC_NAME s_scm_unlock_mutex_timed
+{
+ scm_t_timespec cwaittime, *waittime = NULL;
+
+ SCM_VALIDATE_MUTEX (1, mx);
+ if (! (SCM_UNBNDP (cond)))
+ {
+ SCM_VALIDATE_CONDVAR (2, cond);
+
+ if (! (SCM_UNBNDP (timeout)))
+ {
+ to_timespec (timeout, &cwaittime);
+ waittime = &cwaittime;
+ }
+ }
+
+ return fat_mutex_unlock (mx, cond, waittime, 0) ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_mutex_p, "mutex?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is a mutex.")
+#define FUNC_NAME s_scm_mutex_p
+{
+ return SCM_MUTEXP (obj) ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_mutex_owner, "mutex-owner", 1, 0, 0,
+ (SCM mx),
+ "Return the thread owning @var{mx}, or @code{#f}.")
+#define FUNC_NAME s_scm_mutex_owner
+{
+ SCM owner;
+ fat_mutex *m = NULL;
+
+ SCM_VALIDATE_MUTEX (1, mx);
+ m = SCM_MUTEX_DATA (mx);
+ scm_i_pthread_mutex_lock (&m->lock);
+ owner = m->owner;
+ scm_i_pthread_mutex_unlock (&m->lock);
+
+ return owner;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_mutex_level, "mutex-level", 1, 0, 0,
+ (SCM mx),
+ "Return the lock level of mutex @var{mx}.")
+#define FUNC_NAME s_scm_mutex_level
+{
+ SCM_VALIDATE_MUTEX (1, mx);
+ return scm_from_int (SCM_MUTEX_DATA(mx)->level);
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_mutex_locked_p, "mutex-locked?", 1, 0, 0,
+ (SCM mx),
+ "Returns @code{#t} if the mutex @var{mx} is locked.")
+#define FUNC_NAME s_scm_mutex_locked_p
+{
+ SCM_VALIDATE_MUTEX (1, mx);
+ return SCM_MUTEX_DATA (mx)->level > 0 ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+static int
+fat_cond_print (SCM cv, SCM port, scm_print_state *pstate SCM_UNUSED)
+{
+ fat_cond *c = SCM_CONDVAR_DATA (cv);
+ scm_puts ("#<condition-variable ", port);
+ scm_uintprint ((scm_t_bits)c, 16, port);
+ scm_puts (">", port);
+ return 1;
+}
+
+SCM_DEFINE (scm_make_condition_variable, "make-condition-variable", 0, 0, 0,
+ (void),
+ "Make a new condition variable.")
+#define FUNC_NAME s_scm_make_condition_variable
+{
+ fat_cond *c;
+ SCM cv;
+
+ c = scm_gc_malloc (sizeof (fat_cond), "condition variable");
+ c->waiting = SCM_EOL;
+ SCM_NEWSMOB (cv, scm_tc16_condvar, (scm_t_bits) c);
+ c->waiting = make_queue ();
+ return cv;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_timed_wait_condition_variable, "wait-condition-variable", 2, 1, 0,
+ (SCM cv, SCM mx, SCM t),
+"Wait until condition variable @var{cv} has been signalled. While waiting, "
+"mutex @var{mx} is atomically unlocked (as with @code{unlock-mutex}) and "
+"is locked again when this function returns. When @var{t} is given, "
+"it specifies a point in time where the waiting should be aborted. It "
+"can be either a integer as returned by @code{current-time} or a pair "
+"as returned by @code{gettimeofday}. When the waiting is aborted the "
+"mutex is locked and @code{#f} is returned. When the condition "
+"variable is in fact signalled, the mutex is also locked and @code{#t} "
+"is returned. ")
+#define FUNC_NAME s_scm_timed_wait_condition_variable
+{
+ scm_t_timespec waittime, *waitptr = NULL;
+
+ SCM_VALIDATE_CONDVAR (1, cv);
+ SCM_VALIDATE_MUTEX (2, mx);
+
+ if (!SCM_UNBNDP (t))
+ {
+ to_timespec (t, &waittime);
+ waitptr = &waittime;
+ }
+
+ return fat_mutex_unlock (mx, cv, waitptr, 1) ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+static void
+fat_cond_signal (fat_cond *c)
+{
+ unblock_from_queue (c->waiting);
+}
+
+SCM_DEFINE (scm_signal_condition_variable, "signal-condition-variable", 1, 0, 0,
+ (SCM cv),
+ "Wake up one thread that is waiting for @var{cv}")
+#define FUNC_NAME s_scm_signal_condition_variable
+{
+ SCM_VALIDATE_CONDVAR (1, cv);
+ fat_cond_signal (SCM_CONDVAR_DATA (cv));
+ return SCM_BOOL_T;
+}
+#undef FUNC_NAME
+
+static void
+fat_cond_broadcast (fat_cond *c)
+{
+ while (scm_is_true (unblock_from_queue (c->waiting)))
+ ;
+}
+
+SCM_DEFINE (scm_broadcast_condition_variable, "broadcast-condition-variable", 1, 0, 0,
+ (SCM cv),
+ "Wake up all threads that are waiting for @var{cv}. ")
+#define FUNC_NAME s_scm_broadcast_condition_variable
+{
+ SCM_VALIDATE_CONDVAR (1, cv);
+ fat_cond_broadcast (SCM_CONDVAR_DATA (cv));
+ return SCM_BOOL_T;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_condition_variable_p, "condition-variable?", 1, 0, 0,
+ (SCM obj),
+ "Return @code{#t} if @var{obj} is a condition variable.")
+#define FUNC_NAME s_scm_condition_variable_p
+{
+ return SCM_CONDVARP(obj) ? SCM_BOOL_T : SCM_BOOL_F;
+}
+#undef FUNC_NAME
+
+
+\f
+/*** Select */
+
+struct select_args
+{
+ int nfds;
+ fd_set *read_fds;
+ fd_set *write_fds;
+ fd_set *except_fds;
+ struct timeval *timeout;
+
+ int result;
+ int errno_value;
+};
+
+static void *
+do_std_select (void *args)
+{
+ struct select_args *select_args;
+
+ select_args = (struct select_args *) args;
+
+ select_args->result =
+ select (select_args->nfds,
+ select_args->read_fds, select_args->write_fds,
+ select_args->except_fds, select_args->timeout);
+ select_args->errno_value = errno;
+
+ return NULL;
+}
+
+#if !SCM_HAVE_SYS_SELECT_H
+static int scm_std_select (int nfds,
+ fd_set *readfds,
+ fd_set *writefds,
+ fd_set *exceptfds,
+ struct timeval *timeout);
+#endif
+
+int
+scm_std_select (int nfds,
+ fd_set *readfds,
+ fd_set *writefds,
+ fd_set *exceptfds,
+ struct timeval *timeout)
+{
+ fd_set my_readfds;
+ int res, eno, wakeup_fd;
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+ struct select_args args;
+
+ if (readfds == NULL)
+ {
+ FD_ZERO (&my_readfds);
+ readfds = &my_readfds;
+ }
+
+ while (scm_i_setup_sleep (t, SCM_BOOL_F, NULL, t->sleep_pipe[1]))
+ SCM_TICK;
+
+ wakeup_fd = t->sleep_pipe[0];
+ FD_SET (wakeup_fd, readfds);
+ if (wakeup_fd >= nfds)
+ nfds = wakeup_fd+1;
+
+ args.nfds = nfds;
+ args.read_fds = readfds;
+ args.write_fds = writefds;
+ args.except_fds = exceptfds;
+ args.timeout = timeout;
+
+ /* Explicitly cooperate with the GC. */
+ scm_without_guile (do_std_select, &args);
+
+ res = args.result;
+ eno = args.errno_value;
+
+ t->sleep_fd = -1;
+ scm_i_reset_sleep (t);
+
+ if (res > 0 && FD_ISSET (wakeup_fd, readfds))
+ {
+ char dummy;
+ full_read (wakeup_fd, &dummy, 1);
+
+ FD_CLR (wakeup_fd, readfds);
+ res -= 1;
+ if (res == 0)
+ {
+ eno = EINTR;
+ res = -1;
+ }
+ }
+ errno = eno;
+ return res;
+}
+
+/* Convenience API for blocking while in guile mode. */
+
+#if SCM_USE_PTHREAD_THREADS
+
+/* It seems reasonable to not run procedures related to mutex and condition
+ variables within `GC_do_blocking ()' since, (i) the GC can operate even
+ without it, and (ii) the only potential gain would be GC latency. See
+ http://thread.gmane.org/gmane.comp.programming.garbage-collection.boehmgc/2245/focus=2251
+ for a discussion of the pros and cons. */
+
+int
+scm_pthread_mutex_lock (scm_i_pthread_mutex_t *mutex)
+{
+ int res = scm_i_pthread_mutex_lock (mutex);
+ return res;
+}
+
+static void
+do_unlock (void *data)
+{
+ scm_i_pthread_mutex_unlock ((scm_i_pthread_mutex_t *)data);
+}
+
+void
+scm_dynwind_pthread_mutex_lock (scm_i_pthread_mutex_t *mutex)
+{
+ scm_i_scm_pthread_mutex_lock (mutex);
+ scm_dynwind_unwind_handler (do_unlock, mutex, SCM_F_WIND_EXPLICITLY);
+}
+
+int
+scm_pthread_cond_wait (scm_i_pthread_cond_t *cond, scm_i_pthread_mutex_t *mutex)
+{
+ int res;
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
+ t->held_mutex = mutex;
+ res = scm_i_pthread_cond_wait (cond, mutex);
+ t->held_mutex = NULL;
+
+ return res;
+}
+
+int
+scm_pthread_cond_timedwait (scm_i_pthread_cond_t *cond,
+ scm_i_pthread_mutex_t *mutex,
+ const scm_t_timespec *wt)
+{
+ int res;
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
+ t->held_mutex = mutex;
+ res = scm_i_pthread_cond_timedwait (cond, mutex, wt);
+ t->held_mutex = NULL;
+
+ return res;
+}
+
+#endif
+
+unsigned long
+scm_std_usleep (unsigned long usecs)
+{
+ struct timeval tv;
+ tv.tv_usec = usecs % 1000000;
+ tv.tv_sec = usecs / 1000000;
+ scm_std_select (0, NULL, NULL, NULL, &tv);
+ return tv.tv_sec * 1000000 + tv.tv_usec;
+}
+
+unsigned int
+scm_std_sleep (unsigned int secs)
+{
+ struct timeval tv;
+ tv.tv_usec = 0;
+ tv.tv_sec = secs;
+ scm_std_select (0, NULL, NULL, NULL, &tv);
+ return tv.tv_sec;
+}
+
+/*** Misc */
+
+SCM_DEFINE (scm_current_thread, "current-thread", 0, 0, 0,
+ (void),
+ "Return the thread that called this function.")
+#define FUNC_NAME s_scm_current_thread
+{
+ return SCM_I_CURRENT_THREAD->handle;
+}
+#undef FUNC_NAME
+
+static SCM
+scm_c_make_list (size_t n, SCM fill)
+{
+ SCM res = SCM_EOL;
+ while (n-- > 0)
+ res = scm_cons (fill, res);
+ return res;
+}
+
+SCM_DEFINE (scm_all_threads, "all-threads", 0, 0, 0,
+ (void),
+ "Return a list of all threads.")
+#define FUNC_NAME s_scm_all_threads
+{
+ /* We can not allocate while holding the thread_admin_mutex because
+ of the way GC is done.
+ */
+ int n = thread_count;
+ scm_i_thread *t;
+ SCM list = scm_c_make_list (n, SCM_UNSPECIFIED), *l;
+
+ scm_i_pthread_mutex_lock (&thread_admin_mutex);
+ l = &list;
+ for (t = all_threads; t && n > 0; t = t->next_thread)
+ {
+ if (t != scm_i_signal_delivery_thread)
+ {
+ SCM_SETCAR (*l, t->handle);
+ l = SCM_CDRLOC (*l);
+ }
+ n--;
+ }
+ *l = SCM_EOL;
+ scm_i_pthread_mutex_unlock (&thread_admin_mutex);
+ return list;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_thread_exited_p, "thread-exited?", 1, 0, 0,
+ (SCM thread),
+ "Return @code{#t} iff @var{thread} has exited.\n")
+#define FUNC_NAME s_scm_thread_exited_p
+{
+ return scm_from_bool (scm_c_thread_exited_p (thread));
+}
+#undef FUNC_NAME
+
+int
+scm_c_thread_exited_p (SCM thread)
+#define FUNC_NAME s_scm_thread_exited_p
+{
+ scm_i_thread *t;
+ SCM_VALIDATE_THREAD (1, thread);
+ t = SCM_I_THREAD_DATA (thread);
+ return t->exited;
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_total_processor_count, "total-processor-count", 0, 0, 0,
+ (void),
+ "Return the total number of processors of the machine, which\n"
+ "is guaranteed to be at least 1. A ``processor'' here is a\n"
+ "thread execution unit, which can be either:\n\n"
+ "@itemize\n"
+ "@item an execution core in a (possibly multi-core) chip, in a\n"
+ " (possibly multi- chip) module, in a single computer, or\n"
+ "@item a thread execution unit inside a core in the case of\n"
+ " @dfn{hyper-threaded} CPUs.\n"
+ "@end itemize\n\n"
+ "Which of the two definitions is used, is unspecified.\n")
+#define FUNC_NAME s_scm_total_processor_count
+{
+ return scm_from_ulong (num_processors (NPROC_ALL));
+}
+#undef FUNC_NAME
+
+SCM_DEFINE (scm_current_processor_count, "current-processor-count", 0, 0, 0,
+ (void),
+ "Like @code{total-processor-count}, but return the number of\n"
+ "processors available to the current process. See\n"
+ "@code{setaffinity} and @code{getaffinity} for more\n"
+ "information.\n")
+#define FUNC_NAME s_scm_current_processor_count
+{
+ return scm_from_ulong (num_processors (NPROC_CURRENT));
+}
+#undef FUNC_NAME
+
+
+\f
+
+static scm_i_pthread_cond_t wake_up_cond;
+static int threads_initialized_p = 0;
+
+
+/* This mutex is used by SCM_CRITICAL_SECTION_START/END.
+ */
+scm_i_pthread_mutex_t scm_i_critical_section_mutex;
+
+static SCM dynwind_critical_section_mutex;
+
+void
+scm_dynwind_critical_section (SCM mutex)
+{
+ if (scm_is_false (mutex))
+ mutex = dynwind_critical_section_mutex;
+ scm_dynwind_lock_mutex (mutex);
+ scm_dynwind_block_asyncs ();
+}
+
+/*** Initialization */
+
+scm_i_pthread_mutex_t scm_i_misc_mutex;
+
+#if SCM_USE_PTHREAD_THREADS
+pthread_mutexattr_t scm_i_pthread_mutexattr_recursive[1];
+#endif
+
+void
+scm_threads_prehistory (void *base)
+{
+#if SCM_USE_PTHREAD_THREADS
+ pthread_mutexattr_init (scm_i_pthread_mutexattr_recursive);
+ pthread_mutexattr_settype (scm_i_pthread_mutexattr_recursive,
+ PTHREAD_MUTEX_RECURSIVE);
+#endif
+
+ scm_i_pthread_mutex_init (&scm_i_critical_section_mutex,
+ scm_i_pthread_mutexattr_recursive);
+ scm_i_pthread_mutex_init (&scm_i_misc_mutex, NULL);
+ scm_i_pthread_cond_init (&wake_up_cond, NULL);
+
+ guilify_self_1 ((struct GC_stack_base *) base);
+}
+
+scm_t_bits scm_tc16_thread;
+scm_t_bits scm_tc16_mutex;
+scm_t_bits scm_tc16_condvar;
+
+void
+scm_init_threads ()
+{
+ scm_tc16_thread = scm_make_smob_type ("thread", sizeof (scm_i_thread));
+ scm_set_smob_print (scm_tc16_thread, thread_print);
+
+ scm_tc16_mutex = scm_make_smob_type ("mutex", sizeof (fat_mutex));
+ scm_set_smob_print (scm_tc16_mutex, fat_mutex_print);
+ scm_set_smob_free (scm_tc16_mutex, fat_mutex_free);
+
+ scm_tc16_condvar = scm_make_smob_type ("condition-variable",
+ sizeof (fat_cond));
+ scm_set_smob_print (scm_tc16_condvar, fat_cond_print);
+
+ scm_i_default_dynamic_state = SCM_BOOL_F;
+ guilify_self_2 (SCM_BOOL_F);
+ threads_initialized_p = 1;
+
+ dynwind_critical_section_mutex = scm_make_recursive_mutex ();
+}
+
+void
+scm_init_threads_default_dynamic_state ()
+{
+ SCM state = scm_make_dynamic_state (scm_current_dynamic_state ());
+ scm_i_default_dynamic_state = state;
+}
+
+void
+scm_init_thread_procs ()
+{
+#include "libguile/threads.x"
+}
+
+\f
+/* IA64-specific things. */
+
+#ifdef __ia64__
+# ifdef __hpux
+# include <sys/param.h>
+# include <sys/pstat.h>
+void *
+scm_ia64_register_backing_store_base (void)
+{
+ struct pst_vm_status vm_status;
+ int i = 0;
+ while (pstat_getprocvm (&vm_status, sizeof (vm_status), 0, i++) == 1)
+ if (vm_status.pst_type == PS_RSESTACK)
+ return (void *) vm_status.pst_vaddr;
+ abort ();
+}
+void *
+scm_ia64_ar_bsp (const void *ctx)
+{
+ uint64_t bsp;
+ __uc_get_ar_bsp (ctx, &bsp);
+ return (void *) bsp;
+}
+# endif /* hpux */
+# ifdef linux
+# include <ucontext.h>
+void *
+scm_ia64_register_backing_store_base (void)
+{
+ extern void *__libc_ia64_register_backing_store_base;
+ return __libc_ia64_register_backing_store_base;
+}
+void *
+scm_ia64_ar_bsp (const void *opaque)
+{
+ const ucontext_t *ctx = opaque;
+ return (void *) ctx->uc_mcontext.sc_ar_bsp;
+}
+# endif /* linux */
+# ifdef __FreeBSD__
+# include <ucontext.h>
+void *
+scm_ia64_register_backing_store_base (void)
+{
+ return (void *)0x8000000000000000;
+}
+void *
+scm_ia64_ar_bsp (const void *opaque)
+{
+ const ucontext_t *ctx = opaque;
+ return (void *)(ctx->uc_mcontext.mc_special.bspstore
+ + ctx->uc_mcontext.mc_special.ndirty);
+}
+# endif /* __FreeBSD__ */
+#endif /* __ia64__ */
+
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
HCoop / bpt / guile.git / blobdiff