gtkaccelgroup.c

/* GTK - The GIMP Toolkit
 * Copyright (C) 1998, 2001 Tim Janik
 *
 * 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, see <http://www.gnu.org/licenses/>.
 */

/*
 * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
 */

#include "config.h"
#include <string.h>
#include <stdlib.h>

#include "gtkaccelgroup.h"
#include "gtkaccelgroupprivate.h"
#include "gtkaccellabel.h"
#include "gtkaccelmapprivate.h"
#include "gtkintl.h"
#include "gtkmarshalers.h"
#include "gtkprivate.h"

/**
 * SECTION:gtkaccelgroup
 * @Short_description: Groups of global keyboard accelerators for an
 *     entire GtkWindow
 * @Title: Accelerator Groups
 * @See_also: gtk_window_add_accel_group(), gtk_accel_map_change_entry(),
 * gtk_label_new_with_mnemonic()
 *
 * A #GtkAccelGroup represents a group of keyboard accelerators,
 * typically attached to a toplevel #GtkWindow (with
 * gtk_window_add_accel_group()). Usually you won’t need to create a
 * #GtkAccelGroup directly; instead, when using #GtkUIManager, GTK+
 * automatically sets up the accelerators for your menus in the ui
 * manager’s #GtkAccelGroup.
 *
 * Note that “accelerators” are different from
 * “mnemonics”. Accelerators are shortcuts for
 * activating a menu item; they appear alongside the menu item they’re a
 * shortcut for. For example “Ctrl+Q” might appear alongside the “Quit”
 * menu item. Mnemonics are shortcuts for GUI elements such as text
 * entries or buttons; they appear as underlined characters. See
 * gtk_label_new_with_mnemonic(). Menu items can have both accelerators
 * and mnemonics, of course.
 */

/* --- prototypes --- */
static void gtk_accel_group_finalize     (GObject    *object);
static void gtk_accel_group_get_property (GObject    *object,
                                          guint       param_id,
                                          GValue     *value,
                                          GParamSpec *pspec);
static void accel_closure_invalidate     (gpointer    data,
                                          GClosure   *closure);


/* --- variables --- */
static guint  signal_accel_activate      = 0;
static guint  signal_accel_changed       = 0;
static guint  quark_acceleratable_groups = 0;
static guint  default_accel_mod_mask     = 0;

enum {
  PROP_0,
  PROP_IS_LOCKED,
  PROP_MODIFIER_MASK,
  N_PROPERTIES
};

static GParamSpec *obj_properties[N_PROPERTIES] = { NULL, };

G_DEFINE_TYPE_WITH_PRIVATE (GtkAccelGroup, gtk_accel_group, G_TYPE_OBJECT)


/* --- functions --- */
static void
gtk_accel_group_class_init (GtkAccelGroupClass *class)
{
  GObjectClass *object_class = G_OBJECT_CLASS (class);

  quark_acceleratable_groups = g_quark_from_static_string ("gtk-acceleratable-accel-groups");

  object_class->finalize = gtk_accel_group_finalize;
  object_class->get_property = gtk_accel_group_get_property;

  class->accel_changed = NULL;

  obj_properties [PROP_IS_LOCKED] =
    g_param_spec_boolean ("is-locked",
                          "Is locked",
                          "Is the accel group locked",
                          FALSE,
                          G_PARAM_READABLE);

  obj_properties [PROP_MODIFIER_MASK] =
    g_param_spec_flags ("modifier-mask",
                        "Modifier Mask",
                        "Modifier Mask",
                        GDK_TYPE_MODIFIER_TYPE,
                        default_accel_mod_mask,
                        G_PARAM_READABLE);

   g_object_class_install_properties (object_class,
                                      N_PROPERTIES,
                                      obj_properties);

  /**
   * GtkAccelGroup::accel-activate:
   * @accel_group: the #GtkAccelGroup which received the signal
   * @acceleratable: the object on which the accelerator was activated
   * @keyval: the accelerator keyval
   * @modifier: the modifier combination of the accelerator
   *
   * The accel-activate signal is an implementation detail of
   * #GtkAccelGroup and not meant to be used by applications.
   *
   * Returns: %TRUE if the accelerator was activated
   */
  signal_accel_activate =
    g_signal_new (I_("accel-activate"),
                  G_OBJECT_CLASS_TYPE (class),
                  G_SIGNAL_DETAILED,
                  0,
                  _gtk_boolean_handled_accumulator, NULL,
                  _gtk_marshal_BOOLEAN__OBJECT_UINT_FLAGS,
                  G_TYPE_BOOLEAN, 3,
                  G_TYPE_OBJECT,
                  G_TYPE_UINT,
                  GDK_TYPE_MODIFIER_TYPE);
  /**
   * GtkAccelGroup::accel-changed:
   * @accel_group: the #GtkAccelGroup which received the signal
   * @keyval: the accelerator keyval
   * @modifier: the modifier combination of the accelerator
   * @accel_closure: the #GClosure of the accelerator
   *
   * The accel-changed signal is emitted when an entry
   * is added to or removed from the accel group.
   *
   * Widgets like #GtkAccelLabel which display an associated
   * accelerator should connect to this signal, and rebuild
   * their visual representation if the @accel_closure is theirs.
   */
  signal_accel_changed =
    g_signal_new (I_("accel-changed"),
                  G_OBJECT_CLASS_TYPE (class),
                  G_SIGNAL_RUN_FIRST | G_SIGNAL_DETAILED,
                  G_STRUCT_OFFSET (GtkAccelGroupClass, accel_changed),
                  NULL, NULL,
                  _gtk_marshal_VOID__UINT_FLAGS_BOXED,
                  G_TYPE_NONE, 3,
                  G_TYPE_UINT,
                  GDK_TYPE_MODIFIER_TYPE,
                  G_TYPE_CLOSURE);
}

static void
gtk_accel_group_finalize (GObject *object)
{
  GtkAccelGroup *accel_group = GTK_ACCEL_GROUP (object);
  guint i;

  for (i = 0; i < accel_group->priv->n_accels; i++)
    {
      GtkAccelGroupEntry *entry = &accel_group->priv->priv_accels[i];

      if (entry->accel_path_quark)
        {
          const gchar *accel_path = g_quark_to_string (entry->accel_path_quark);

          _gtk_accel_map_remove_group (accel_path, accel_group);
        }
      g_closure_remove_invalidate_notifier (entry->closure, accel_group, accel_closure_invalidate);

      /* remove quick_accel_add() refcount */
      g_closure_unref (entry->closure);
    }

  g_free (accel_group->priv->priv_accels);

  G_OBJECT_CLASS (gtk_accel_group_parent_class)->finalize (object);
}

static void
gtk_accel_group_get_property (GObject    *object,
                              guint       param_id,
                              GValue     *value,
                              GParamSpec *pspec)
{
  GtkAccelGroup *accel_group = GTK_ACCEL_GROUP (object);

  switch (param_id)
    {
    case PROP_IS_LOCKED:
      g_value_set_boolean (value, accel_group->priv->lock_count > 0);
      break;
    case PROP_MODIFIER_MASK:
      g_value_set_flags (value, accel_group->priv->modifier_mask);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
      break;
    }
}

static void
gtk_accel_group_init (GtkAccelGroup *accel_group)
{
  GtkAccelGroupPrivate *priv;

  accel_group->priv = gtk_accel_group_get_instance_private (accel_group);
  priv = accel_group->priv;

  priv->lock_count = 0;
  priv->modifier_mask = gtk_accelerator_get_default_mod_mask ();
  priv->acceleratables = NULL;
  priv->n_accels = 0;
  priv->priv_accels = NULL;
}

/**
 * gtk_accel_group_new:
 *
 * Creates a new #GtkAccelGroup.
 *
 * Returns: a new #GtkAccelGroup object
 */
GtkAccelGroup*
gtk_accel_group_new (void)
{
  return g_object_new (GTK_TYPE_ACCEL_GROUP, NULL);
}

/**
 * gtk_accel_group_get_is_locked:
 * @accel_group: a #GtkAccelGroup
 *
 * Locks are added and removed using gtk_accel_group_lock() and
 * gtk_accel_group_unlock().
 *
 * Returns: %TRUE if there are 1 or more locks on the @accel_group,
 *     %FALSE otherwise.
 *
 * Since: 2.14
 */
gboolean
gtk_accel_group_get_is_locked (GtkAccelGroup *accel_group)
{
  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), FALSE);

  return accel_group->priv->lock_count > 0;
}

/**
 * gtk_accel_group_get_modifier_mask:
 * @accel_group: a #GtkAccelGroup
 *
 * Gets a #GdkModifierType representing the mask for this
 * @accel_group. For example, #GDK_CONTROL_MASK, #GDK_SHIFT_MASK, etc.
 *
 * Returns: the modifier mask for this accel group.
 *
 * Since: 2.14
 */
GdkModifierType
gtk_accel_group_get_modifier_mask (GtkAccelGroup *accel_group)
{
  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), 0);

  return accel_group->priv->modifier_mask;
}

static void
accel_group_weak_ref_detach (GSList  *free_list,
                             GObject *stale_object)
{
  GSList *slist;

  for (slist = free_list; slist; slist = slist->next)
    {
      GtkAccelGroup *accel_group;

      accel_group = slist->data;
      accel_group->priv->acceleratables = g_slist_remove (accel_group->priv->acceleratables, stale_object);
      g_object_unref (accel_group);
    }
  g_slist_free (free_list);
  g_object_set_qdata (stale_object, quark_acceleratable_groups, NULL);
}

void
_gtk_accel_group_attach (GtkAccelGroup *accel_group,
                         GObject       *object)
{
  GSList *slist;

  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));
  g_return_if_fail (G_IS_OBJECT (object));
  g_return_if_fail (g_slist_find (accel_group->priv->acceleratables, object) == NULL);

  g_object_ref (accel_group);
  accel_group->priv->acceleratables = g_slist_prepend (accel_group->priv->acceleratables, object);
  slist = g_object_get_qdata (object, quark_acceleratable_groups);
  if (slist)
    g_object_weak_unref (object,
                         (GWeakNotify) accel_group_weak_ref_detach,
                         slist);
  slist = g_slist_prepend (slist, accel_group);
  g_object_set_qdata (object, quark_acceleratable_groups, slist);
  g_object_weak_ref (object,
                     (GWeakNotify) accel_group_weak_ref_detach,
                     slist);
}

void
_gtk_accel_group_detach (GtkAccelGroup *accel_group,
                         GObject       *object)
{
  GSList *slist;

  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));
  g_return_if_fail (G_IS_OBJECT (object));
  g_return_if_fail (g_slist_find (accel_group->priv->acceleratables, object) != NULL);

  accel_group->priv->acceleratables = g_slist_remove (accel_group->priv->acceleratables, object);
  slist = g_object_get_qdata (object, quark_acceleratable_groups);
  g_object_weak_unref (object,
                       (GWeakNotify) accel_group_weak_ref_detach,
                       slist);
  slist = g_slist_remove (slist, accel_group);
  g_object_set_qdata (object, quark_acceleratable_groups, slist);
  if (slist)
    g_object_weak_ref (object,
                       (GWeakNotify) accel_group_weak_ref_detach,
                       slist);
  g_object_unref (accel_group);
}

/**
 * gtk_accel_groups_from_object:
 * @object: a #GObject, usually a #GtkWindow
 *
 * Gets a list of all accel groups which are attached to @object.
 *
 * Returns: (element-type GtkAccelGroup) (transfer none): a list of
 *     all accel groups which are attached to @object
 */
GSList*
gtk_accel_groups_from_object (GObject *object)
{
  g_return_val_if_fail (G_IS_OBJECT (object), NULL);

  return g_object_get_qdata (object, quark_acceleratable_groups);
}

/**
 * gtk_accel_group_find:
 * @accel_group: a #GtkAccelGroup
 * @find_func: (scope call): a function to filter the entries
 *    of @accel_group with
 * @data: data to pass to @find_func
 *
 * Finds the first entry in an accelerator group for which
 * @find_func returns %TRUE and returns its #GtkAccelKey.
 *
 * Returns: (transfer none): the key of the first entry passing
 *    @find_func. The key is owned by GTK+ and must not be freed.
 */
GtkAccelKey*
gtk_accel_group_find (GtkAccelGroup         *accel_group,
                      GtkAccelGroupFindFunc  find_func,
                      gpointer               data)
{
  GtkAccelKey *key = NULL;
  guint i;

  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), NULL);
  g_return_val_if_fail (find_func != NULL, NULL);

  g_object_ref (accel_group);
  for (i = 0; i < accel_group->priv->n_accels; i++)
    if (find_func (&accel_group->priv->priv_accels[i].key,
                   accel_group->priv->priv_accels[i].closure,
                   data))
      {
        key = &accel_group->priv->priv_accels[i].key;
        break;
      }
  g_object_unref (accel_group);

  return key;
}

/**
 * gtk_accel_group_lock:
 * @accel_group: a #GtkAccelGroup
 *
 * Locks the given accelerator group.
 *
 * Locking an acelerator group prevents the accelerators contained
 * within it to be changed during runtime. Refer to
 * gtk_accel_map_change_entry() about runtime accelerator changes.
 *
 * If called more than once, @accel_group remains locked until
 * gtk_accel_group_unlock() has been called an equivalent number
 * of times.
 */
void
gtk_accel_group_lock (GtkAccelGroup *accel_group)
{
  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));

  accel_group->priv->lock_count += 1;

  if (accel_group->priv->lock_count == 1) {
    /* State change from unlocked to locked */
    g_object_notify_by_pspec (G_OBJECT (accel_group), obj_properties[PROP_IS_LOCKED]);
  }
}

/**
 * gtk_accel_group_unlock:
 * @accel_group: a #GtkAccelGroup
 *
 * Undoes the last call to gtk_accel_group_lock() on this @accel_group.
 */
void
gtk_accel_group_unlock (GtkAccelGroup *accel_group)
{
  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));
  g_return_if_fail (accel_group->priv->lock_count > 0);

  accel_group->priv->lock_count -= 1;

  if (accel_group->priv->lock_count < 1) {
    /* State change from locked to unlocked */
    g_object_notify_by_pspec (G_OBJECT (accel_group), obj_properties[PROP_IS_LOCKED]);
  }
}

static void
accel_closure_invalidate (gpointer  data,
                          GClosure *closure)
{
  GtkAccelGroup *accel_group = GTK_ACCEL_GROUP (data);

  gtk_accel_group_disconnect (accel_group, closure);
}

static int
bsearch_compare_accels (const void *d1,
                        const void *d2)
{
  const GtkAccelGroupEntry *entry1 = d1;
  const GtkAccelGroupEntry *entry2 = d2;

  if (entry1->key.accel_key == entry2->key.accel_key)
    return entry1->key.accel_mods < entry2->key.accel_mods ? -1 : entry1->key.accel_mods > entry2->key.accel_mods;
  else
    return entry1->key.accel_key < entry2->key.accel_key ? -1 : 1;
}

static void
quick_accel_add (GtkAccelGroup   *accel_group,
                 guint            accel_key,
                 GdkModifierType  accel_mods,
                 GtkAccelFlags    accel_flags,
                 GClosure        *closure,
                 GQuark           path_quark)
{
  guint pos, i = accel_group->priv->n_accels++;
  GtkAccelGroupEntry key;

  /* find position */
  key.key.accel_key = accel_key;
  key.key.accel_mods = accel_mods;
  for (pos = 0; pos < i; pos++)
    if (bsearch_compare_accels (&key, accel_group->priv->priv_accels + pos) < 0)
      break;

  /* insert at position, ref closure */
  accel_group->priv->priv_accels = g_renew (GtkAccelGroupEntry, accel_group->priv->priv_accels, accel_group->priv->n_accels);
  memmove (accel_group->priv->priv_accels + pos + 1, accel_group->priv->priv_accels + pos,
           (i - pos) * sizeof (accel_group->priv->priv_accels[0]));
  accel_group->priv->priv_accels[pos].key.accel_key = accel_key;
  accel_group->priv->priv_accels[pos].key.accel_mods = accel_mods;
  accel_group->priv->priv_accels[pos].key.accel_flags = accel_flags;
  accel_group->priv->priv_accels[pos].closure = g_closure_ref (closure);
  accel_group->priv->priv_accels[pos].accel_path_quark = path_quark;
  g_closure_sink (closure);

  /* handle closure invalidation and reverse lookups */
  g_closure_add_invalidate_notifier (closure, accel_group, accel_closure_invalidate);

  /* get accel path notification */
  if (path_quark)
    _gtk_accel_map_add_group (g_quark_to_string (path_quark), accel_group);

  /* connect and notify changed */
  if (accel_key)
    {
      gchar *accel_name = gtk_accelerator_name (accel_key, accel_mods);
      GQuark accel_quark = g_quark_from_string (accel_name);

      g_free (accel_name);

      /* setup handler */
      g_signal_connect_closure_by_id (accel_group, signal_accel_activate, accel_quark, closure, FALSE);

      /* and notify */
      g_signal_emit (accel_group, signal_accel_changed, accel_quark, accel_key, accel_mods, closure);
    }
}

static void
quick_accel_remove (GtkAccelGroup *accel_group,
                    guint          pos)
{
  GQuark accel_quark = 0;
  GtkAccelGroupEntry *entry = accel_group->priv->priv_accels + pos;
  guint accel_key = entry->key.accel_key;
  GdkModifierType accel_mods = entry->key.accel_mods;
  GClosure *closure = entry->closure;

  /* quark for notification */
  if (accel_key)
    {
      gchar *accel_name = gtk_accelerator_name (accel_key, accel_mods);

      accel_quark = g_quark_from_string (accel_name);
      g_free (accel_name);
    }

  /* clean up closure invalidate notification and disconnect */
  g_closure_remove_invalidate_notifier (entry->closure, accel_group, accel_closure_invalidate);
  if (accel_quark)
    g_signal_handlers_disconnect_matched (accel_group,
                                          G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_DETAIL | G_SIGNAL_MATCH_CLOSURE,
                                          signal_accel_activate, accel_quark,
                                          closure, NULL, NULL);
  /* clean up accel path notification */
  if (entry->accel_path_quark)
    _gtk_accel_map_remove_group (g_quark_to_string (entry->accel_path_quark), accel_group);

  /* physically remove */
  accel_group->priv->n_accels -= 1;
  memmove (entry, entry + 1,
           (accel_group->priv->n_accels - pos) * sizeof (accel_group->priv->priv_accels[0]));

  /* and notify */
  if (accel_quark)
    g_signal_emit (accel_group, signal_accel_changed, accel_quark, accel_key, accel_mods, closure);

  /* remove quick_accel_add() refcount */
  g_closure_unref (closure);
}

static GtkAccelGroupEntry*
quick_accel_find (GtkAccelGroup   *accel_group,
                  guint            accel_key,
                  GdkModifierType  accel_mods,
                  guint           *count_p)
{
  GtkAccelGroupEntry *entry;
  GtkAccelGroupEntry key;

  *count_p = 0;

  if (!accel_group->priv->n_accels)
    return NULL;

  key.key.accel_key = accel_key;
  key.key.accel_mods = accel_mods;
  entry = bsearch (&key, accel_group->priv->priv_accels, accel_group->priv->n_accels,
                   sizeof (accel_group->priv->priv_accels[0]), bsearch_compare_accels);

  if (!entry)
    return NULL;

  /* step back to the first member */
  for (; entry > accel_group->priv->priv_accels; entry--)
    if (entry[-1].key.accel_key != accel_key ||
        entry[-1].key.accel_mods != accel_mods)
      break;
  /* count equal members */
  for (; entry + *count_p < accel_group->priv->priv_accels + accel_group->priv->n_accels; (*count_p)++)
    if (entry[*count_p].key.accel_key != accel_key ||
        entry[*count_p].key.accel_mods != accel_mods)
      break;
  return entry;
}

/**
 * gtk_accel_group_connect:
 * @accel_group: the accelerator group to install an accelerator in
 * @accel_key: key value of the accelerator
 * @accel_mods: modifier combination of the accelerator
 * @accel_flags: a flag mask to configure this accelerator
 * @closure: closure to be executed upon accelerator activation
 *
 * Installs an accelerator in this group. When @accel_group is being
 * activated in response to a call to gtk_accel_groups_activate(),
 * @closure will be invoked if the @accel_key and @accel_mods from
 * gtk_accel_groups_activate() match those of this connection.
 *
 * The signature used for the @closure is that of #GtkAccelGroupActivate.
 *
 * Note that, due to implementation details, a single closure can
 * only be connected to one accelerator group.
 */
void
gtk_accel_group_connect (GtkAccelGroup   *accel_group,
                         guint            accel_key,
                         GdkModifierType  accel_mods,
                         GtkAccelFlags    accel_flags,
                         GClosure        *closure)
{
  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));
  g_return_if_fail (closure != NULL);
  g_return_if_fail (accel_key > 0);
  g_return_if_fail (gtk_accel_group_from_accel_closure (closure) == NULL);

  g_object_ref (accel_group);
  if (!closure->is_invalid)
    quick_accel_add (accel_group,
                     gdk_keyval_to_lower (accel_key),
                     accel_mods, accel_flags, closure, 0);
  g_object_unref (accel_group);
}

/**
 * gtk_accel_group_connect_by_path:
 * @accel_group: the accelerator group to install an accelerator in
 * @accel_path: path used for determining key and modifiers
 * @closure: closure to be executed upon accelerator activation
 *
 * Installs an accelerator in this group, using an accelerator path
 * to look up the appropriate key and modifiers (see
 * gtk_accel_map_add_entry()). When @accel_group is being activated
 * in response to a call to gtk_accel_groups_activate(), @closure will
 * be invoked if the @accel_key and @accel_mods from
 * gtk_accel_groups_activate() match the key and modifiers for the path.
 *
 * The signature used for the @closure is that of #GtkAccelGroupActivate.
 *
 * Note that @accel_path string will be stored in a #GQuark. Therefore,
 * if you pass a static string, you can save some memory by interning it
 * first with g_intern_static_string().
 */
void
gtk_accel_group_connect_by_path (GtkAccelGroup *accel_group,
                                 const gchar   *accel_path,
                                 GClosure      *closure)
{
  guint accel_key = 0;
  GdkModifierType accel_mods = 0;
  GtkAccelKey key;

  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));
  g_return_if_fail (closure != NULL);
  g_return_if_fail (_gtk_accel_path_is_valid (accel_path));

  if (closure->is_invalid)
    return;

  g_object_ref (accel_group);

  if (gtk_accel_map_lookup_entry (accel_path, &key))
    {
      accel_key = gdk_keyval_to_lower (key.accel_key);
      accel_mods = key.accel_mods;
    }

  quick_accel_add (accel_group, accel_key, accel_mods, GTK_ACCEL_VISIBLE, closure,
                   g_quark_from_string (accel_path));

  g_object_unref (accel_group);
}

/**
 * gtk_accel_group_disconnect:
 * @accel_group: the accelerator group to remove an accelerator from
 * @closure: (allow-none): the closure to remove from this accelerator
 *     group, or %NULL to remove all closures
 *
 * Removes an accelerator previously installed through
 * gtk_accel_group_connect().
 *
 * Since 2.20 @closure can be %NULL.
 *
 * Returns: %TRUE if the closure was found and got disconnected
 */
gboolean
gtk_accel_group_disconnect (GtkAccelGroup *accel_group,
                            GClosure      *closure)
{
  guint i;

  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), FALSE);

  for (i = 0; i < accel_group->priv->n_accels; i++)
    if (accel_group->priv->priv_accels[i].closure == closure)
      {
        g_object_ref (accel_group);
        quick_accel_remove (accel_group, i);
        g_object_unref (accel_group);
        return TRUE;
      }
  return FALSE;
}

/**
 * gtk_accel_group_disconnect_key:
 * @accel_group: the accelerator group to install an accelerator in
 * @accel_key: key value of the accelerator
 * @accel_mods: modifier combination of the accelerator
 *
 * Removes an accelerator previously installed through
 * gtk_accel_group_connect().
 *
 * Returns: %TRUE if there was an accelerator which could be
 *     removed, %FALSE otherwise
 */
gboolean
gtk_accel_group_disconnect_key (GtkAccelGroup   *accel_group,
                                guint            accel_key,
                                GdkModifierType  accel_mods)
{
  GtkAccelGroupEntry *entries;
  GSList *slist, *clist = NULL;
  gboolean removed_one = FALSE;
  guint n;

  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), FALSE);

  g_object_ref (accel_group);

  accel_key = gdk_keyval_to_lower (accel_key);
  entries = quick_accel_find (accel_group, accel_key, accel_mods, &n);
  while (n--)
    {
      GClosure *closure = g_closure_ref (entries[n].closure);

      clist = g_slist_prepend (clist, closure);
    }

  for (slist = clist; slist; slist = slist->next)
    {
      GClosure *closure = slist->data;

      removed_one |= gtk_accel_group_disconnect (accel_group, closure);
      g_closure_unref (closure);
    }
  g_slist_free (clist);

  g_object_unref (accel_group);

  return removed_one;
}

void
_gtk_accel_group_reconnect (GtkAccelGroup *accel_group,
                            GQuark         accel_path_quark)
{
  GSList *slist, *clist = NULL;
  guint i;

  g_return_if_fail (GTK_IS_ACCEL_GROUP (accel_group));

  g_object_ref (accel_group);

  for (i = 0; i < accel_group->priv->n_accels; i++)
    if (accel_group->priv->priv_accels[i].accel_path_quark == accel_path_quark)
      {
        GClosure *closure = g_closure_ref (accel_group->priv->priv_accels[i].closure);

        clist = g_slist_prepend (clist, closure);
      }

  for (slist = clist; slist; slist = slist->next)
    {
      GClosure *closure = slist->data;

      gtk_accel_group_disconnect (accel_group, closure);
      gtk_accel_group_connect_by_path (accel_group, g_quark_to_string (accel_path_quark), closure);
      g_closure_unref (closure);
    }
  g_slist_free (clist);

  g_object_unref (accel_group);
}

GSList*
_gtk_accel_group_get_accelerables (GtkAccelGroup *accel_group)
{
    g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), NULL);

    return accel_group->priv->acceleratables;
}

/**
 * gtk_accel_group_query:
 * @accel_group: the accelerator group to query
 * @accel_key: key value of the accelerator
 * @accel_mods: modifier combination of the accelerator
 * @n_entries: (out) (optional): location to return the number
 *     of entries found, or %NULL
 *
 * Queries an accelerator group for all entries matching @accel_key
 * and @accel_mods.
 *
 * Returns: (nullable) (transfer none) (array length=n_entries): an array of
 *     @n_entries #GtkAccelGroupEntry elements, or %NULL. The array
 *     is owned by GTK+ and must not be freed.
 */
GtkAccelGroupEntry*
gtk_accel_group_query (GtkAccelGroup   *accel_group,
                       guint            accel_key,
                       GdkModifierType  accel_mods,
                       guint           *n_entries)
{
  GtkAccelGroupEntry *entries;
  guint n;

  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), NULL);

  entries = quick_accel_find (accel_group, gdk_keyval_to_lower (accel_key), accel_mods, &n);

  if (n_entries)
    *n_entries = entries ? n : 0;

  return entries;
}

/**
 * gtk_accel_group_from_accel_closure:
 * @closure: a #GClosure
 *
 * Finds the #GtkAccelGroup to which @closure is connected;
 * see gtk_accel_group_connect().
 *
 * Returns: (nullable) (transfer none): the #GtkAccelGroup to which @closure
 *     is connected, or %NULL
 */
GtkAccelGroup*
gtk_accel_group_from_accel_closure (GClosure *closure)
{
  guint i;

  g_return_val_if_fail (closure != NULL, NULL);

  /* A few remarks on what we do here. in general, we need a way to
   * reverse lookup accel_groups from closures that are being used in
   * accel groups. this could be done e.g via a hashtable. it is however
   * cheaper (memory wise) to just use the invalidation notifier on the
   * closure itself (which we need to install anyway), that contains the
   * accel group as data which, besides needing to peek a bit at closure
   * internals, works just as good.
   */
  for (i = 0; i < G_CLOSURE_N_NOTIFIERS (closure); i++)
    if (closure->notifiers[i].notify == accel_closure_invalidate)
      return closure->notifiers[i].data;

  return NULL;
}

/**
 * gtk_accel_group_activate:
 * @accel_group: a #GtkAccelGroup
 * @accel_quark: the quark for the accelerator name
 * @acceleratable: the #GObject, usually a #GtkWindow, on which
 *    to activate the accelerator
 * @accel_key: accelerator keyval from a key event
 * @accel_mods: keyboard state mask from a key event
 *
 * Finds the first accelerator in @accel_group that matches
 * @accel_key and @accel_mods, and activates it.
 *
 * Returns: %TRUE if an accelerator was activated and handled
 *     this keypress
 */
gboolean
gtk_accel_group_activate (GtkAccelGroup   *accel_group,
                          GQuark           accel_quark,
                          GObject         *acceleratable,
                          guint            accel_key,
                          GdkModifierType  accel_mods)
{
  gboolean was_handled;

  g_return_val_if_fail (GTK_IS_ACCEL_GROUP (accel_group), FALSE);
  g_return_val_if_fail (G_IS_OBJECT (acceleratable), FALSE);

  was_handled = FALSE;
  g_signal_emit (accel_group, signal_accel_activate, accel_quark,
                 acceleratable, accel_key, accel_mods, &was_handled);

  return was_handled;
}

/**
 * gtk_accel_groups_activate:
 * @object: the #GObject, usually a #GtkWindow, on which
 *     to activate the accelerator
 * @accel_key: accelerator keyval from a key event
 * @accel_mods: keyboard state mask from a key event
 *
 * Finds the first accelerator in any #GtkAccelGroup attached
 * to @object that matches @accel_key and @accel_mods, and
 * activates that accelerator.
 *
 * Returns: %TRUE if an accelerator was activated and handled
 *     this keypress
 */
gboolean
gtk_accel_groups_activate (GObject         *object,
                           guint            accel_key,
                           GdkModifierType  accel_mods)
{
  g_return_val_if_fail (G_IS_OBJECT (object), FALSE);