-/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002 Free Software Foundation, Inc.
+/* Copyright (C) 1995,1996,1997,1998,2000,2001, 2002, 2004, 2006, 2008, 2009, 2010 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 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 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.
+ * 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 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. */
+ * 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
+
+#define SCM_BUILDING_DEPRECATED_CODE
#include <signal.h>
#include "libguile/_scm.h"
#include "libguile/throw.h"
#include "libguile/root.h"
#include "libguile/smob.h"
-#include "libguile/lang.h"
#include "libguile/dynwind.h"
#include "libguile/deprecation.h"
#include <unistd.h>
#endif
-/* This is not used for anything except checking that DEFER_INTS and
- ALLOW_INTS are used properly.
- */
-int scm_ints_disabled = 1;
+#include <full-write.h>
\f
/* {Asynchronous Events}
/* cmm: this has SCM_ prefix because SCM_MAKE_VALIDATE expects it.
this is ugly. */
#define SCM_ASYNCP(X) SCM_TYP16_PREDICATE (tc16_async, X)
-#define VALIDATE_ASYNC(pos, a) SCM_MAKE_VALIDATE(pos, a, ASYNCP)
+#define VALIDATE_ASYNC(pos, a) SCM_MAKE_VALIDATE_MSG(pos, a, ASYNCP, "user async")
-#define ASYNC_GOT_IT(X) (SCM_CELL_WORD_0 (X) >> 16)
-#define SET_ASYNC_GOT_IT(X, V) (SCM_SET_CELL_WORD_0 ((X), SCM_TYP16 (X) | ((V) << 16)))
-#define ASYNC_THUNK(X) SCM_CELL_OBJECT_1 (X)
+#define ASYNC_GOT_IT(X) (SCM_SMOB_FLAGS (X))
+#define SET_ASYNC_GOT_IT(X, V) (SCM_SET_SMOB_FLAGS ((X), ((V))))
+#define ASYNC_THUNK(X) SCM_SMOB_OBJECT_1 (X)
-static SCM
-async_gc_mark (SCM obj)
-{
- return ASYNC_THUNK (obj);
-}
SCM_DEFINE (scm_async, "async", 1, 0, 0,
(SCM thunk),
\f
+static scm_i_pthread_mutex_t async_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER;
+
/* System asyncs. */
void
scm_async_click ()
{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
SCM asyncs;
- if (scm_root->block_asyncs == 0)
+ /* Reset pending_asyncs even when asyncs are blocked and not really
+ executed since this will avoid future futile calls to this
+ function. When asyncs are unblocked again, this function is
+ invoked even when pending_asyncs is zero.
+ */
+
+ scm_i_scm_pthread_mutex_lock (&async_mutex);
+ t->pending_asyncs = 0;
+ if (t->block_asyncs == 0)
{
- while (!SCM_NULLP(asyncs = scm_root->active_asyncs))
- {
- scm_root->active_asyncs = SCM_EOL;
- do
- {
- SCM c = SCM_CDR (asyncs);
- SCM_SETCDR (asyncs, SCM_BOOL_F);
- scm_call_0 (SCM_CAR (asyncs));
- asyncs = c;
- }
- while (!SCM_NULLP(asyncs));
- }
+ asyncs = t->active_asyncs;
+ t->active_asyncs = SCM_EOL;
+ }
+ else
+ asyncs = SCM_EOL;
+ scm_i_pthread_mutex_unlock (&async_mutex);
+
+ while (scm_is_pair (asyncs))
+ {
+ SCM next = SCM_CDR (asyncs);
+ SCM_SETCDR (asyncs, SCM_BOOL_F);
+ scm_call_0 (SCM_CAR (asyncs));
+ asyncs = next;
}
}
SCM_DEFINE (scm_system_async, "system-async", 1, 0, 0,
(SCM thunk),
"This function is deprecated. You can use @var{thunk} directly\n"
- "instead of explicitely creating an async object.\n")
+ "instead of explicitly creating an async object.\n")
#define FUNC_NAME s_scm_system_async
{
scm_c_issue_deprecation_warning
#endif /* SCM_ENABLE_DEPRECATED == 1 */
void
-scm_i_queue_async_cell (SCM c, scm_root_state *root)
+scm_i_queue_async_cell (SCM c, scm_i_thread *t)
{
- if (SCM_CDR (c) == SCM_BOOL_F)
+ SCM sleep_object;
+ scm_i_pthread_mutex_t *sleep_mutex;
+ int sleep_fd;
+ SCM p;
+
+ scm_i_scm_pthread_mutex_lock (&async_mutex);
+ p = t->active_asyncs;
+ SCM_SETCDR (c, SCM_EOL);
+ if (!scm_is_pair (p))
+ t->active_asyncs = c;
+ else
{
- SCM p = root->active_asyncs;
- SCM_SETCDR (c, SCM_EOL);
- if (p == SCM_EOL)
- root->active_asyncs = c;
- else
+ SCM pp;
+ while (scm_is_pair (pp = SCM_CDR (p)))
{
- SCM pp;
- while ((pp = SCM_CDR(p)) != SCM_EOL)
+ if (scm_is_eq (SCM_CAR (p), SCM_CAR (c)))
{
- if (SCM_CAR (p) == SCM_CAR (c))
- return;
- p = pp;
+ scm_i_pthread_mutex_unlock (&async_mutex);
+ return;
}
- SCM_SETCDR (p, c);
+ p = pp;
}
+ SCM_SETCDR (p, c);
+ }
+ t->pending_asyncs = 1;
+ sleep_object = t->sleep_object;
+ sleep_mutex = t->sleep_mutex;
+ sleep_fd = t->sleep_fd;
+ scm_i_pthread_mutex_unlock (&async_mutex);
+
+ if (sleep_mutex)
+ {
+ /* By now, the thread T might be out of its sleep already, or
+ might even be in the next, unrelated sleep. Interrupting it
+ anyway does no harm, however.
+
+ The important thing to prevent here is to signal sleep_cond
+ before T waits on it. This can not happen since T has
+ sleep_mutex locked while setting t->sleep_mutex and will only
+ unlock it again while waiting on sleep_cond.
+ */
+ scm_i_scm_pthread_mutex_lock (sleep_mutex);
+ scm_i_pthread_cond_signal (&t->sleep_cond);
+ scm_i_pthread_mutex_unlock (sleep_mutex);
+ }
+
+ if (sleep_fd >= 0)
+ {
+ char dummy = 0;
+
+ /* Likewise, T might already been done with sleeping here, but
+ interrupting it once too often does no harm. T might also
+ not yet have started sleeping, but this is no problem either
+ since the data written to a pipe will not be lost, unlike a
+ condition variable signal. */
+ full_write (sleep_fd, &dummy, 1);
}
+
+ /* This is needed to protect sleep_mutex.
+ */
+ scm_remember_upto_here_1 (sleep_object);
+}
+
+int
+scm_i_setup_sleep (scm_i_thread *t,
+ SCM sleep_object, scm_i_pthread_mutex_t *sleep_mutex,
+ int sleep_fd)
+{
+ int pending;
+
+ scm_i_scm_pthread_mutex_lock (&async_mutex);
+ pending = t->pending_asyncs;
+ if (!pending)
+ {
+ t->sleep_object = sleep_object;
+ t->sleep_mutex = sleep_mutex;
+ t->sleep_fd = sleep_fd;
+ }
+ scm_i_pthread_mutex_unlock (&async_mutex);
+ return pending;
+}
+
+void
+scm_i_reset_sleep (scm_i_thread *t)
+{
+ scm_i_scm_pthread_mutex_lock (&async_mutex);
+ t->sleep_object = SCM_BOOL_F;
+ t->sleep_mutex = NULL;
+ t->sleep_fd = -1;
+ scm_i_pthread_mutex_unlock (&async_mutex);
}
SCM_DEFINE (scm_system_async_mark_for_thread, "system-async-mark", 1, 1, 0,
"signal handlers.")
#define FUNC_NAME s_scm_system_async_mark_for_thread
{
-#ifdef USE_THREADS
+ /* The current thread might not have a handle yet. This can happen
+ when the GC runs immediately before allocating the handle. At
+ the end of that GC, a system async might be marked. Thus, we can
+ not use scm_current_thread here.
+ */
+
+ scm_i_thread *t;
+
if (SCM_UNBNDP (thread))
- thread = scm_current_thread ();
+ t = SCM_I_CURRENT_THREAD;
else
- SCM_VALIDATE_THREAD (2, thread);
-
- scm_i_queue_async_cell (scm_cons (proc, SCM_BOOL_F),
- scm_i_thread_root (thread));
-#else
- scm_i_queue_async_cell (scm_cons (proc, SCM_BOOL_F), scm_root);
-#endif
+ {
+ SCM_VALIDATE_THREAD (2, thread);
+ if (scm_c_thread_exited_p (thread))
+ SCM_MISC_ERROR ("thread has already exited", SCM_EOL);
+ t = SCM_I_THREAD_DATA (thread);
+ }
+ scm_i_queue_async_cell (scm_cons (proc, SCM_BOOL_F), t);
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
"Unmask signals. The returned value is not specified.")
#define FUNC_NAME s_scm_unmask_signals
{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
scm_c_issue_deprecation_warning
("'unmask-signals' is deprecated. "
"Use 'call-with-blocked-asyncs' instead.");
- if (scm_root->block_asyncs == 0)
+ if (t->block_asyncs == 0)
SCM_MISC_ERROR ("signals already unmasked", SCM_EOL);
- scm_root->block_asyncs = 0;
+ t->block_asyncs = 0;
+ scm_async_click ();
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
"Mask signals. The returned value is not specified.")
#define FUNC_NAME s_scm_mask_signals
{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+
scm_c_issue_deprecation_warning
("'mask-signals' is deprecated. Use 'call-with-blocked-asyncs' instead.");
- if (scm_root->block_asyncs > 0)
+ if (t->block_asyncs > 0)
SCM_MISC_ERROR ("signals already masked", SCM_EOL);
- scm_root->block_asyncs = 1;
+ t->block_asyncs = 1;
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif /* SCM_ENABLE_DEPRECATED == 1 */
static void
-increase_block (void *unused)
+increase_block (void *data)
{
- scm_root->block_asyncs++;
+ ((scm_i_thread *)data)->block_asyncs++;
}
static void
-decrease_block (void *unused)
+decrease_block (void *data)
{
- scm_root->block_asyncs--;
+ if (--((scm_i_thread *)data)->block_asyncs == 0)
+ scm_async_click ();
}
SCM_DEFINE (scm_call_with_blocked_asyncs, "call-with-blocked-asyncs", 1, 0, 0,
return scm_internal_dynamic_wind (increase_block,
(scm_t_inner) scm_call_0,
decrease_block,
- proc, NULL);
+ (void *)proc,
+ SCM_I_CURRENT_THREAD);
}
#undef FUNC_NAME
void *
scm_c_call_with_blocked_asyncs (void *(*proc) (void *data), void *data)
{
- return scm_internal_dynamic_wind (increase_block,
- (scm_t_inner) proc,
- decrease_block,
- data, NULL);
+ return (void *)scm_internal_dynamic_wind (increase_block,
+ (scm_t_inner) proc,
+ decrease_block,
+ data,
+ SCM_I_CURRENT_THREAD);
}
"it is running. Return the value returned by @var{proc}.\n")
#define FUNC_NAME s_scm_call_with_unblocked_asyncs
{
- if (scm_root->block_asyncs == 0)
+ if (SCM_I_CURRENT_THREAD->block_asyncs == 0)
SCM_MISC_ERROR ("asyncs already unblocked", SCM_EOL);
return scm_internal_dynamic_wind (decrease_block,
(scm_t_inner) scm_call_0,
increase_block,
- proc, NULL);
+ (void *)proc,
+ SCM_I_CURRENT_THREAD);
}
#undef FUNC_NAME
void *
scm_c_call_with_unblocked_asyncs (void *(*proc) (void *data), void *data)
{
- if (scm_root->block_asyncs == 0)
+ if (SCM_I_CURRENT_THREAD->block_asyncs == 0)
scm_misc_error ("scm_c_call_with_unblocked_asyncs",
"asyncs already unblocked", SCM_EOL);
- return scm_internal_dynamic_wind (decrease_block,
- (scm_t_inner) proc,
- increase_block,
- data, NULL);
+ return (void *)scm_internal_dynamic_wind (decrease_block,
+ (scm_t_inner) proc,
+ increase_block,
+ data,
+ SCM_I_CURRENT_THREAD);
+}
+
+void
+scm_dynwind_block_asyncs ()
+{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+ scm_dynwind_rewind_handler (increase_block, t, SCM_F_WIND_EXPLICITLY);
+ scm_dynwind_unwind_handler (decrease_block, t, SCM_F_WIND_EXPLICITLY);
+}
+
+void
+scm_dynwind_unblock_asyncs ()
+{
+ scm_i_thread *t = SCM_I_CURRENT_THREAD;
+ if (t->block_asyncs == 0)
+ scm_misc_error ("scm_with_unblocked_asyncs",
+ "asyncs already unblocked", SCM_EOL);
+ scm_dynwind_rewind_handler (decrease_block, t, SCM_F_WIND_EXPLICITLY);
+ scm_dynwind_unwind_handler (increase_block, t, SCM_F_WIND_EXPLICITLY);
+}
+
+\f
+/* These are function variants of the same-named macros (uppercase) for use
+ outside of libguile. This is so that `SCM_I_CURRENT_THREAD', which may
+ reside in TLS, is not accessed from outside of libguile. It thus allows
+ libguile to be built with the "local-dynamic" TLS model. */
+
+void
+scm_critical_section_start (void)
+{
+ SCM_CRITICAL_SECTION_START;
+}
+
+void
+scm_critical_section_end (void)
+{
+ SCM_CRITICAL_SECTION_END;
+}
+
+void
+scm_async_tick (void)
+{
+ SCM_ASYNC_TICK;
}
\f
void
scm_init_async ()
{
- scm_asyncs = SCM_EOL;
tc16_async = scm_make_smob_type ("async", 0);
- scm_set_smob_mark (tc16_async, async_gc_mark);
#include "libguile/async.x"
}
HCoop / bpt / guile.git / blobdiff