gclosure.c

嵌入式下基于MiniGUI的Web Browser

/* GObject - GLib Type, Object, Parameter and Signal Library
 * Copyright (C) 2000-2001 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.
 */

#include	"gclosure.h"

#include	"gvalue.h"
#include	<string.h>


/* FIXME: need caching allocators
 */

#define	CLOSURE_MAX_REF_COUNT		((1 << 15) - 1)
#define	CLOSURE_MAX_N_GUARDS		((1 << 1) - 1)
#define	CLOSURE_MAX_N_FNOTIFIERS	((1 << 2) - 1)
#define	CLOSURE_MAX_N_INOTIFIERS	((1 << 8) - 1)
#define	CLOSURE_N_MFUNCS(cl)		((cl)->meta_marshal + \
                                         ((cl)->n_guards << 1L))
/* same as G_CLOSURE_N_NOTIFIERS() (keep in sync) */
#define	CLOSURE_N_NOTIFIERS(cl)		(CLOSURE_N_MFUNCS (cl) + \
                                         (cl)->n_fnotifiers + \
                                         (cl)->n_inotifiers)
enum {
  FNOTIFY,
  INOTIFY,
  PRE_NOTIFY,
  POST_NOTIFY
};


/* --- functions --- */
GClosure*
g_closure_new_simple (guint           sizeof_closure,
		      gpointer        data)
{
  GClosure *closure;

  g_return_val_if_fail (sizeof_closure >= sizeof (GClosure), NULL);

  closure = g_malloc (sizeof_closure);
  closure->ref_count = 1;
  closure->meta_marshal = 0;
  closure->n_guards = 0;
  closure->n_fnotifiers = 0;
  closure->n_inotifiers = 0;
  closure->in_inotify = FALSE;
  closure->floating = TRUE;
  closure->derivative_flag = 0;
  closure->in_marshal = FALSE;
  closure->is_invalid = FALSE;
  closure->marshal = NULL;
  closure->data = data;
  closure->notifiers = NULL;
  memset (G_STRUCT_MEMBER_P (closure, sizeof (*closure)), 0, sizeof_closure - sizeof (*closure));

  return closure;
}

static inline void
closure_invoke_notifiers (GClosure *closure,
			  guint     notify_type)
{
  /* notifier layout:
   *     meta_marshal  n_guards    n_guards     n_fnotif.  n_inotifiers
   * ->[[meta_marshal][pre_guards][post_guards][fnotifiers][inotifiers]]
   *
   * CLOSURE_N_MFUNCS(cl)    = meta_marshal + n_guards + n_guards;
   * CLOSURE_N_NOTIFIERS(cl) = CLOSURE_N_MFUNCS(cl) + n_fnotifiers + n_inotifiers
   *
   * constrains/catches:
   * - closure->notifiers may be reloacted during callback
   * - closure->n_fnotifiers and closure->n_inotifiers may change during callback
   * - i.e. callbacks can be removed/added during invocation
   * - have to prepare for callback removal during invocation (->marshal & ->data)
   * - have to distinguish (->marshal & ->data) for INOTIFY/FNOTIFY (->in_inotify)
   * + closure->n_guards is const during PRE_NOTIFY & POST_NOTIFY
   * + closure->meta_marshal is const for all cases
   * + none of the callbacks can cause recursion
   * + closure->n_inotifiers is const 0 during FNOTIFY
   */
  switch (notify_type)
    {
      GClosureNotifyData *ndata;
      guint i, offs;
    case FNOTIFY:
      while (closure->n_fnotifiers)
	{
	  register guint n = --closure->n_fnotifiers;

	  ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + n;
	  closure->marshal = (GClosureMarshal) ndata->notify;
	  closure->data = ndata->data;
	  ndata->notify (ndata->data, closure);
	}
      closure->marshal = NULL;
      closure->data = NULL;
      break;
    case INOTIFY:
      closure->in_inotify = TRUE;
      while (closure->n_inotifiers)
	{
          register guint n = --closure->n_inotifiers;

	  ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + n;
	  closure->marshal = (GClosureMarshal) ndata->notify;
	  closure->data = ndata->data;
	  ndata->notify (ndata->data, closure);
	}
      closure->marshal = NULL;
      closure->data = NULL;
      closure->in_inotify = FALSE;
      break;
    case PRE_NOTIFY:
      i = closure->n_guards;
      offs = closure->meta_marshal;
      while (i--)
	{
	  ndata = closure->notifiers + offs + i;
	  ndata->notify (ndata->data, closure);
	}
      break;
    case POST_NOTIFY:
      i = closure->n_guards;
      offs = closure->meta_marshal + i;
      while (i--)
	{
	  ndata = closure->notifiers + offs + i;
	  ndata->notify (ndata->data, closure);
	}
      break;
    }
}

void
g_closure_set_meta_marshal (GClosure       *closure,
			    gpointer        marshal_data,
			    GClosureMarshal meta_marshal)
{
  GClosureNotifyData *notifiers;
  guint n;

  g_return_if_fail (closure != NULL);
  g_return_if_fail (meta_marshal != NULL);
  g_return_if_fail (closure->is_invalid == FALSE);
  g_return_if_fail (closure->in_marshal == FALSE);
  g_return_if_fail (closure->meta_marshal == 0);

  n = CLOSURE_N_NOTIFIERS (closure);
  notifiers = closure->notifiers;
  closure->notifiers = g_renew (GClosureNotifyData, NULL, CLOSURE_N_NOTIFIERS (closure) + 1);
  if (notifiers)
    {
      /* usually the meta marshal will be setup right after creation, so the
       * g_memmove() should be rare-case scenario
       */
      g_memmove (closure->notifiers + 1, notifiers, CLOSURE_N_NOTIFIERS (closure) * sizeof (notifiers[0]));
      g_free (notifiers);
    }
  closure->notifiers[0].data = marshal_data;
  closure->notifiers[0].notify = (GClosureNotify) meta_marshal;
  closure->meta_marshal = 1;
}

void
g_closure_add_marshal_guards (GClosure      *closure,
			      gpointer       pre_marshal_data,
			      GClosureNotify pre_marshal_notify,
			      gpointer       post_marshal_data,
			      GClosureNotify post_marshal_notify)
{
  guint i;

  g_return_if_fail (closure != NULL);
  g_return_if_fail (pre_marshal_notify != NULL);
  g_return_if_fail (post_marshal_notify != NULL);
  g_return_if_fail (closure->is_invalid == FALSE);
  g_return_if_fail (closure->in_marshal == FALSE);
  g_return_if_fail (closure->n_guards < CLOSURE_MAX_N_GUARDS);

  closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 2);
  if (closure->n_inotifiers)
    closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
			closure->n_fnotifiers +
			closure->n_inotifiers + 1)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
									  closure->n_fnotifiers + 0)];
  if (closure->n_inotifiers > 1)
    closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
			closure->n_fnotifiers +
			closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
								      closure->n_fnotifiers + 1)];
  if (closure->n_fnotifiers)
    closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
			closure->n_fnotifiers + 1)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 0];
  if (closure->n_fnotifiers > 1)
    closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
			closure->n_fnotifiers)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 1];
  if (closure->n_guards)
    closure->notifiers[(closure->meta_marshal +
			closure->n_guards +
			closure->n_guards + 1)] = closure->notifiers[closure->meta_marshal + closure->n_guards];
  i = closure->n_guards++;
  closure->notifiers[closure->meta_marshal + i].data = pre_marshal_data;
  closure->notifiers[closure->meta_marshal + i].notify = pre_marshal_notify;
  closure->notifiers[closure->meta_marshal + i + 1].data = post_marshal_data;
  closure->notifiers[closure->meta_marshal + i + 1].notify = post_marshal_notify;
}

void
g_closure_add_finalize_notifier (GClosure      *closure,
				 gpointer       notify_data,
				 GClosureNotify notify_func)
{
  guint i;

  g_return_if_fail (closure != NULL);
  g_return_if_fail (notify_func != NULL);
  g_return_if_fail (closure->n_fnotifiers < CLOSURE_MAX_N_FNOTIFIERS);

  closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1);
  if (closure->n_inotifiers)
    closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
			closure->n_fnotifiers +
			closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) +
								      closure->n_fnotifiers + 0)];
  i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers++;
  closure->notifiers[i].data = notify_data;
  closure->notifiers[i].notify = notify_func;
}

void
g_closure_add_invalidate_notifier (GClosure      *closure,
				   gpointer       notify_data,
				   GClosureNotify notify_func)
{
  guint i;

  g_return_if_fail (closure != NULL);
  g_return_if_fail (notify_func != NULL);
  g_return_if_fail (closure->is_invalid == FALSE);
  g_return_if_fail (closure->n_inotifiers < CLOSURE_MAX_N_INOTIFIERS);

  closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1);
  i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers++;
  closure->notifiers[i].data = notify_data;
  closure->notifiers[i].notify = notify_func;
}

static inline gboolean
closure_try_remove_inotify (GClosure       *closure,
			    gpointer       notify_data,
			    GClosureNotify notify_func)
{
  GClosureNotifyData *ndata, *nlast;

  nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - 1;
  for (ndata = nlast + 1 - closure->n_inotifiers; ndata <= nlast; ndata++)
    if (ndata->notify == notify_func && ndata->data == notify_data)
      {
	closure->n_inotifiers -= 1;
	if (ndata < nlast)
	  *ndata = *nlast;

	return TRUE;
      }
  return FALSE;