gobject/gobjectnotifyqueue.c

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 1998-1999, 2000-2001 Tim Janik and Red Hat, Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General
  15  * Public License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #ifndef __G_OBJECT_NOTIFY_QUEUE_H__
  21 #define __G_OBJECT_NOTIFY_QUEUE_H__
  22
  23 #include <string.h> /* memset */
  24
  25 #include <glib-object.h>
  26
  27 G_BEGIN_DECLS
  28
  29
  30 /* --- typedefs --- */
  31 typedef struct _GObjectNotifyContext          GObjectNotifyContext;
  32 typedef struct _GObjectNotifyQueue            GObjectNotifyQueue;
  33 typedef void (*GObjectNotifyQueueDispatcher) (GObject     *object,
  34                                               guint        n_pspecs,
  35                                               GParamSpec **pspecs);
  36
  37
  38 /* --- structures --- */
  39 struct _GObjectNotifyContext
  40 {
  41   GQuark                       quark_notify_queue;
  42   GObjectNotifyQueueDispatcher dispatcher;
  43   GTrashStack                 *_nqueue_trash; /* unused */
  44 };
  45 struct _GObjectNotifyQueue
  46 {
  47   GObjectNotifyContext *context;
  48   GSList               *pspecs;
  49   guint16               n_pspecs;
  50   guint16               freeze_count;
  51 };
  52
  53 /* --- functions --- */
  54 static void
  55 g_object_notify_queue_free (gpointer data)
  56 {
  57   GObjectNotifyQueue *nqueue = data;
  58
  59   g_slist_free (nqueue->pspecs);
  60   g_slice_free (GObjectNotifyQueue, nqueue);
  61 }
  62
  63 static inline GObjectNotifyQueue*
  64 g_object_notify_queue_freeze (GObject              *object,
  65                               GObjectNotifyContext *context)
  66 {
  67   GObjectNotifyQueue *nqueue;
  68
  69   nqueue = g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
  70   if (!nqueue)
  71     {
  72       nqueue = g_slice_new0 (GObjectNotifyQueue);
  73       nqueue->context = context;
  74       g_datalist_id_set_data_full (&object->qdata, context->quark_notify_queue,
  75                                    nqueue, g_object_notify_queue_free);
  76     }
  77
  78   g_return_val_if_fail (nqueue->freeze_count < 65535, nqueue);
  79   nqueue->freeze_count++;
  80
  81   return nqueue;
  82 }
  83
  84 static inline void
  85 g_object_notify_queue_thaw (GObject            *object,
  86                             GObjectNotifyQueue *nqueue)
  87 {
  88   GObjectNotifyContext *context = nqueue->context;
  89   GParamSpec *pspecs_mem[16], **pspecs, **free_me = NULL;
  90   GSList *slist;
  91   guint n_pspecs = 0;
  92
  93   g_return_if_fail (nqueue->freeze_count > 0);
  94
  95   nqueue->freeze_count--;
  96   if (nqueue->freeze_count)
  97     return;
  98   g_return_if_fail (object->ref_count > 0);
  99
 100   pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;
 101   /* set first entry to NULL since it's checked unconditionally */
 102   pspecs[0] = NULL;
 103   for (slist = nqueue->pspecs; slist; slist = slist->next)
 104     {
 105       GParamSpec *pspec = slist->data;
 106       guint i = 0;
 107
 108       /* dedup, make pspecs in the list unique */
 109     redo_dedup_check:
 110       if (pspecs[i] == pspec)
 111         continue;
 112       if (++i < n_pspecs)
 113         goto redo_dedup_check;
 114
 115       pspecs[n_pspecs++] = pspec;
 116     }
 117   g_datalist_id_set_data (&object->qdata, context->quark_notify_queue, NULL);
 118
 119   if (n_pspecs)
 120     context->dispatcher (object, n_pspecs, pspecs);
 121   g_free (free_me);
 122 }
 123
 124 static inline void
 125 g_object_notify_queue_clear (GObject            *object,
 126                              GObjectNotifyQueue *nqueue)
 127 {
 128   g_return_if_fail (nqueue->freeze_count > 0);
 129
 130   g_slist_free (nqueue->pspecs);
 131   nqueue->pspecs = NULL;
 132   nqueue->n_pspecs = 0;
 133 }
 134
 135 static inline void
 136 g_object_notify_queue_add (GObject            *object,
 137                            GObjectNotifyQueue *nqueue,
 138                            GParamSpec         *pspec)
 139 {
 140   if (pspec->flags & G_PARAM_READABLE)
 141     {
 142       GParamSpec *redirect;
 143
 144       g_return_if_fail (nqueue->n_pspecs < 65535);
 145
 146       redirect = g_param_spec_get_redirect_target (pspec);
 147       if (redirect)
 148         pspec = redirect;
 149
 150       /* we do the deduping in _thaw */
 151       nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);
 152       nqueue->n_pspecs++;
 153     }
 154 }
 155
 156 static inline GObjectNotifyQueue*
 157 g_object_notify_queue_from_object (GObject              *object,
 158                                    GObjectNotifyContext *context)
 159 {
 160   return g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
 161 }
 162
 163
 164 G_END_DECLS
 165
 166 #endif /* __G_OBJECT_NOTIFY_QUEUE_H__ */