/*
  threadpool.c  -  Manage pools of threads

  Copyright (C)         Lumiera.org
    2009,               Michael Ploujnikov <ploujj@gmail.com>

  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 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.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

//TODO: Support library includes//

#include "include/logging.h"
#include "lib/safeclib.h"

//TODO: Lumiera header includes//
#include "backend/threadpool.h"

//TODO: internal/static forward declarations//
static lumiera_threadpool threadpool;

//TODO: System includes//
#include <pthread.h>

/**
 * @file
 *
 */

//NOBUG_DEFINE_FLAG_PARENT (threadpool, lumiera); /*TODO insert a suitable/better parent flag here */


//code goes here//

void* pool_thread_loop(void * arg)
{
  (void) arg;
  while (1)
    {
      ;
    }
  return arg;
}

void
lumiera_threadpool_init(void)
{
  for (int i = 0; i < LUMIERA_THREADCLASS_COUNT; ++i)
    {
      llist_init(&threadpool.kind[i].pool);
      lumiera_mutex_init(&threadpool.kind[i].lock,"pool of threads", NULL);
    }
}

LumieraThread
lumiera_threadpool_acquire_thread(enum lumiera_thread_class kind,
                                  const char* purpose,
                                  struct nobug_flag* flag)
{
  // TODO: do we need to check that index 'kind' is within range?
  llist pool = threadpool.kind[kind].pool;
  // TODO: do we need to check that we get a valid list?

  // TODO: do proper locking when manipulating the list
  if (llist_is_empty (&pool))
    {
      return lumiera_thread_new (kind, NULL, purpose, flag);
    }
 else
   {
     // use an existing thread, pick the first one
     // remove it from the pool's list
     return (LumieraThread)(llist_unlink(llist_head (&pool)));
   }
}

void
lumiera_threadpool_release_thread(LumieraThread thread)
{
  // TODO: do we need to check that index 'kind' is within range?
  llist pool = threadpool.kind[thread->kind].pool;
  llist_insert_head(&pool, &thread->node);
}

/*
// Local Variables:
// mode: C
// c-file-style: "gnu"
// indent-tabs-mode: nil
// End:
*/