/* classes: h_files */

#ifndef SCM_FUTURES_H
#define SCM_FUTURES_H

/* Copyright (C) 2002, 2003, 2006 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 2.1 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
 */



#if 0

/* Futures have the following known bugs, which should be fixed before
   including them in Guile:

   - The implementation of the thread cache needs to be better so that
     it behaves reasonable under heavy use.

   - The dynamic state of a thread needs to be properly initialized
     when it is retrieved from the cache.
*/

#include "libguile/__scm.h"
#include "libguile/threads.h"



typedef struct scm_t_future {
  SCM data;
  scm_i_pthread_mutex_t mutex;
  scm_i_pthread_cond_t cond;
  int status;
  int die_p;
} scm_t_future;

#define SCM_FUTURE_DEAD 0
#define SCM_FUTURE_SIGNAL_ME -1
#define SCM_FUTURE_COMPUTING 1
#define SCM_FUTURE_TASK_ASSIGNED 2

#define SCM_VALIDATE_FUTURE(pos, obj) \
  SCM_ASSERT_TYPE (SCM_TYP16_PREDICATE (scm_tc16_future, obj), \
		   obj, pos, FUNC_NAME, "future");
#define SCM_FUTURE(future) ((scm_t_future *) SCM_SMOB_DATA_2 (future))
#define SCM_FUTURE_MUTEX(future) (&SCM_FUTURE (future)->mutex)
#define SCM_FUTURE_COND(future) (&SCM_FUTURE (future)->cond)
#define SCM_FUTURE_STATUS(future) (SCM_FUTURE (future)->status)
#define SCM_SET_FUTURE_STATUS(future, x) \
 do { SCM_FUTURE (future)->status = (x); } while (0)
#define SCM_FUTURE_ALIVE_P(future) (SCM_FUTURE_STATUS (future))
#define SCM_FUTURE_DATA(future) (SCM_FUTURE (future)->data)
#define SCM_SET_FUTURE_DATA(future, x) \
 do { SCM_FUTURE (future)->data = (x); } while (0)
#define SCM_FUTURE_NEXT       SCM_SMOB_OBJECT
#define SCM_FUTURE_NEXTLOC    SCM_SMOB_OBJECT_LOC
#define SCM_SET_FUTURE_NEXT   SCM_SET_SMOB_OBJECT

SCM_API scm_t_bits scm_tc16_future;

extern SCM *scm_loc_sys_thread_handler;

SCM_API SCM scm_i_make_future (SCM thunk);
SCM_API SCM scm_make_future (SCM thunk);
SCM_API SCM scm_future_ref (SCM future);

void scm_init_futures (void);

#endif  /* Futures are disabled for now. */

#endif  /* SCM_FUTURES_H */

/*
  Local Variables:
  c-file-style: "gnu"
  End:
*/