/* GObject - GLib Type, Object, Parameter and Signal Library

 * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, 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 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., 59 Temple Place, Suite 330,

 * Boston, MA 02111-1307, USA.

 */

#ifndef __G_OBJECT_NOTIFY_QUEUE_H__

#define __G_OBJECT_NOTIFY_QUEUE_H__

#include <string.h> /* memset */

#include <glib-object.h>

G_BEGIN_DECLS

/* --- typedefs --- */

#if (!EMULATOR)

typedef struct _GObjectNotifyContext          GObjectNotifyContext;

#endif

typedef struct _GObjectNotifyQueue            GObjectNotifyQueue;

#if (!EMULATOR)

typedef void (*GObjectNotifyQueueDispatcher) (GObject     *object,

					      guint        n_pspecs,

					      GParamSpec **pspecs);

/* --- structures --- */

struct _GObjectNotifyContext

{

  GQuark                       quark_notify_queue;

  GObjectNotifyQueueDispatcher dispatcher;

  GTrashStack                 *_nqueue_trash; /* unused */

};

#endif

struct _GObjectNotifyQueue

{

  GObjectNotifyContext *context;

  GSList               *pspecs;

  guint16               n_pspecs;

  guint16               freeze_count;

  /* currently, this structure abuses the GList allocation chain and thus

   * must be <= sizeof (GList)

   */

};

/* --- functions --- */

static void

g_object_notify_queue_free (gpointer data)

{

  GObjectNotifyQueue *nqueue = data;

  g_slist_free (nqueue->pspecs);

  g_list_free_1 ((void*) nqueue);

}

static inline GObjectNotifyQueue*

g_object_notify_queue_freeze (GObject		   *object,

			      GObjectNotifyContext *context)

{

  GObjectNotifyQueue *nqueue;

  nqueue = g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);

  if (!nqueue)

    {

      nqueue = (void*) g_list_alloc ();

      memset (nqueue, 0, sizeof (*nqueue));

      nqueue->context = context;

      g_datalist_id_set_data_full (&object->qdata, context->quark_notify_queue,

				   nqueue, g_object_notify_queue_free);

    }

  g_return_val_if_fail (nqueue->freeze_count < 65535, nqueue);

  nqueue->freeze_count++;

  return nqueue;

}

static inline void

g_object_notify_queue_thaw (GObject            *object,

			    GObjectNotifyQueue *nqueue)

{

  GObjectNotifyContext *context = nqueue->context;

  GParamSpec *pspecs_mem[16], **pspecs, **free_me = NULL;

  GSList *slist;

  guint n_pspecs = 0;

  g_return_if_fail (nqueue->freeze_count > 0);

  nqueue->freeze_count--;

  if (nqueue->freeze_count)

    return;

  g_return_if_fail (object->ref_count > 0);

  pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;

  /* set first entry to NULL since it's checked unconditionally */

  pspecs[0] = NULL;

  for (slist = nqueue->pspecs; slist; slist = slist->next)

    {

      GParamSpec *pspec = slist->data;

      guint i = 0;

      /* dedup, make pspecs in the list unique */

    redo_dedup_check:

      if (pspecs[i] == pspec)

	continue;

      if (++i < n_pspecs)

	goto redo_dedup_check;

      pspecs[n_pspecs++] = pspec;

    }

  g_datalist_id_set_data (&object->qdata, context->quark_notify_queue, NULL);

  if (n_pspecs)

    context->dispatcher (object, n_pspecs, pspecs);

  g_free (free_me);

}

static inline void

g_object_notify_queue_clear (GObject            *object,

			     GObjectNotifyQueue *nqueue)

{

  g_return_if_fail (nqueue->freeze_count > 0);

  g_slist_free (nqueue->pspecs);

  nqueue->pspecs = NULL;

  nqueue->n_pspecs = 0;

}

static inline void

g_object_notify_queue_add (GObject            *object,

			   GObjectNotifyQueue *nqueue,

			   GParamSpec	      *pspec)

{

  if (pspec->flags & G_PARAM_READABLE)

    {

      GParamSpec *redirect;

      g_return_if_fail (nqueue->n_pspecs < 65535);

      redirect = g_param_spec_get_redirect_target (pspec);

      if (redirect)

	pspec = redirect;

      /* we do the deduping in _thaw */

      nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);

      nqueue->n_pspecs++;

    }

}

static inline GObjectNotifyQueue*

g_object_notify_queue_from_object (GObject              *object,

				   GObjectNotifyContext *context)

{

  return g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);

}

G_END_DECLS

#endif /* __G_OBJECT_NOTIFY_QUEUE_H__ */