#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#define SCM_BUILDING_DEPRECATED_CODE
#include "libguile/_scm.h"
#include "libguile/eval.h"
#include "libguile/throw.h"
#include "libguile/root.h"
#include "libguile/smob.h"
#include "libguile/dynwind.h"
#include "libguile/deprecation.h"
#include "libguile/validate.h"
#include "libguile/async.h"
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <unistd.h>
#include <full-write.h>
static scm_t_bits tc16_async;
#define SCM_ASYNCP(X) SCM_TYP16_PREDICATE (tc16_async, X)
#define VALIDATE_ASYNC(pos, a) SCM_MAKE_VALIDATE_MSG(pos, a, ASYNCP, "user async")
#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)
SCM_DEFINE (scm_async, "async", 1, 0, 0,
(SCM thunk),
"Create a new async for the procedure @var{thunk}.")
#define FUNC_NAME s_scm_async
{
SCM_RETURN_NEWSMOB (tc16_async, SCM_UNPACK (thunk));
}
#undef FUNC_NAME
SCM_DEFINE (scm_async_mark, "async-mark", 1, 0, 0,
(SCM a),
"Mark the async @var{a} for future execution.")
#define FUNC_NAME s_scm_async_mark
{
VALIDATE_ASYNC (1, a);
SET_ASYNC_GOT_IT (a, 1);
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
SCM_DEFINE (scm_run_asyncs, "run-asyncs", 1, 0, 0,
(SCM list_of_a),
"Execute all thunks from the asyncs of the list @var{list_of_a}.")
#define FUNC_NAME s_scm_run_asyncs
{
while (! SCM_NULL_OR_NIL_P (list_of_a))
{
SCM a;
SCM_VALIDATE_CONS (1, list_of_a);
a = SCM_CAR (list_of_a);
VALIDATE_ASYNC (SCM_ARG1, a);
if (ASYNC_GOT_IT (a))
{
SET_ASYNC_GOT_IT (a, 0);
scm_call_0 (ASYNC_THUNK (a));
}
list_of_a = SCM_CDR (list_of_a);
}
return SCM_BOOL_T;
}
#undef FUNC_NAME
static scm_i_pthread_mutex_t async_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER;
void
scm_async_click ()
{
scm_i_thread *t = SCM_I_CURRENT_THREAD;
SCM asyncs;
scm_i_scm_pthread_mutex_lock (&async_mutex);
t->pending_asyncs = 0;
if (t->block_asyncs == 0)
{
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;
}
}
#if (SCM_ENABLE_DEPRECATED == 1)
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 explicitly creating an async object.\n")
#define FUNC_NAME s_scm_system_async
{
scm_c_issue_deprecation_warning
("'system-async' is deprecated. "
"Use the procedure directly with 'system-async-mark'.");
return thunk;
}
#undef FUNC_NAME
#endif
void
scm_i_queue_async_cell (SCM c, scm_i_thread *t)
{
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 pp;
while (scm_is_pair (pp = SCM_CDR (p)))
{
if (scm_is_eq (SCM_CAR (p), SCM_CAR (c)))
{
scm_i_pthread_mutex_unlock (&async_mutex);
return;
}
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)
{
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;
full_write (sleep_fd, &dummy, 1);
}
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,
(SCM proc, SCM thread),
"Mark @var{proc} (a procedure with zero arguments) for future execution\n"
"in @var{thread}. If @var{proc} has already been marked for\n"
"@var{thread} but has not been executed yet, this call has no effect.\n"
"If @var{thread} is omitted, the thread that called\n"
"@code{system-async-mark} is used.\n\n"
"This procedure is not safe to be called from C signal handlers. Use\n"
"@code{scm_sigaction} or @code{scm_sigaction_for_thread} to install\n"
"signal handlers.")
#define FUNC_NAME s_scm_system_async_mark_for_thread
{
scm_i_thread *t;
if (SCM_UNBNDP (thread))
t = SCM_I_CURRENT_THREAD;
else
{
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
SCM
scm_system_async_mark (SCM proc)
#define FUNC_NAME s_scm_system_async_mark_for_thread
{
return scm_system_async_mark_for_thread (proc, SCM_UNDEFINED);
}
#undef FUNC_NAME
SCM_DEFINE (scm_noop, "noop", 0, 0, 1,
(SCM args),
"Do nothing. When called without arguments, return @code{#f},\n"
"otherwise return the first argument.")
#define FUNC_NAME s_scm_noop
{
SCM_VALIDATE_REST_ARGUMENT (args);
return (SCM_NULL_OR_NIL_P (args) ? SCM_BOOL_F : SCM_CAR (args));
}
#undef FUNC_NAME
#if (SCM_ENABLE_DEPRECATED == 1)
SCM_DEFINE (scm_unmask_signals, "unmask-signals", 0, 0, 0,
(),
"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 (t->block_asyncs == 0)
SCM_MISC_ERROR ("signals already unmasked", SCM_EOL);
t->block_asyncs = 0;
scm_async_click ();
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
SCM_DEFINE (scm_mask_signals, "mask-signals", 0, 0, 0,
(),
"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 (t->block_asyncs > 0)
SCM_MISC_ERROR ("signals already masked", SCM_EOL);
t->block_asyncs = 1;
return SCM_UNSPECIFIED;
}
#undef FUNC_NAME
#endif
static void
increase_block (void *data)
{
scm_i_thread *t = data;
t->block_asyncs++;
}
static void
decrease_block (void *data)
{
scm_i_thread *t = data;
if (--t->block_asyncs == 0)
scm_async_click ();
}
void
scm_dynwind_block_asyncs (void)
{
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 (void)
{
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);
}
SCM_DEFINE (scm_call_with_blocked_asyncs, "call-with-blocked-asyncs", 1, 0, 0,
(SCM proc),
"Call @var{proc} with no arguments and block the execution\n"
"of system asyncs by one level for the current thread while\n"
"it is running. Return the value returned by @var{proc}.\n")
#define FUNC_NAME s_scm_call_with_blocked_asyncs
{
SCM ans;
scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
scm_dynwind_block_asyncs ();
ans = scm_call_0 (proc);
scm_dynwind_end ();
return ans;
}
#undef FUNC_NAME
void *
scm_c_call_with_blocked_asyncs (void *(*proc) (void *data), void *data)
{
void* ans;
scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
scm_dynwind_block_asyncs ();
ans = proc (data);
scm_dynwind_end ();
return ans;
}
SCM_DEFINE (scm_call_with_unblocked_asyncs, "call-with-unblocked-asyncs", 1, 0, 0,
(SCM proc),
"Call @var{proc} with no arguments and unblock the execution\n"
"of system asyncs by one level for the current thread while\n"
"it is running. Return the value returned by @var{proc}.\n")
#define FUNC_NAME s_scm_call_with_unblocked_asyncs
{
SCM ans;
if (SCM_I_CURRENT_THREAD->block_asyncs == 0)
SCM_MISC_ERROR ("asyncs already unblocked", SCM_EOL);
scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
scm_dynwind_unblock_asyncs ();
ans = scm_call_0 (proc);
scm_dynwind_end ();
return ans;
}
#undef FUNC_NAME
void *
scm_c_call_with_unblocked_asyncs (void *(*proc) (void *data), void *data)
{
void* ans;
if (SCM_I_CURRENT_THREAD->block_asyncs == 0)
scm_misc_error ("scm_c_call_with_unblocked_asyncs",
"asyncs already unblocked", SCM_EOL);
scm_dynwind_begin (SCM_F_DYNWIND_REWINDABLE);
scm_dynwind_unblock_asyncs ();
ans = proc (data);
scm_dynwind_end ();
return ans;
}
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;
}
void
scm_init_async ()
{
tc16_async = scm_make_smob_type ("async", 0);
#include "libguile/async.x"
}