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
27G_BEGIN_DECLS
28
29
30/* --- typedefs --- */
31typedef struct _GObjectNotifyContext          GObjectNotifyContext;
32typedef struct _GObjectNotifyQueue            GObjectNotifyQueue;
33typedef void (*GObjectNotifyQueueDispatcher) (GObject     *object,
34					      guint        n_pspecs,
35					      GParamSpec **pspecs);
36
37
38/* --- structures --- */
39struct _GObjectNotifyContext
40{
41  GQuark                       quark_notify_queue;
42  GObjectNotifyQueueDispatcher dispatcher;
43  GTrashStack                 *_nqueue_trash; /* unused */
44};
45struct _GObjectNotifyQueue
46{
47  GObjectNotifyContext *context;
48  GSList               *pspecs;
49  guint16               n_pspecs;
50  guint16               freeze_count;
51  /* currently, this structure abuses the GList allocation chain and thus
52   * must be <= sizeof (GList)
53   */
54};
55
56
57/* --- functions --- */
58static void
59g_object_notify_queue_free (gpointer data)
60{
61  GObjectNotifyQueue *nqueue = data;
62
63  g_slist_free (nqueue->pspecs);
64  g_list_free_1 ((void*) nqueue);
65}
66
67static inline GObjectNotifyQueue*
68g_object_notify_queue_freeze (GObject		   *object,
69			      GObjectNotifyContext *context)
70{
71  GObjectNotifyQueue *nqueue;
72
73  nqueue = g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
74  if (!nqueue)
75    {
76      nqueue = (void*) g_list_alloc ();
77      memset (nqueue, 0, sizeof (*nqueue));
78      nqueue->context = context;
79      g_datalist_id_set_data_full (&object->qdata, context->quark_notify_queue,
80				   nqueue, g_object_notify_queue_free);
81    }
82
83  g_return_val_if_fail (nqueue->freeze_count < 65535, nqueue);
84  nqueue->freeze_count++;
85
86  return nqueue;
87}
88
89static inline void
90g_object_notify_queue_thaw (GObject            *object,
91			    GObjectNotifyQueue *nqueue)
92{
93  GObjectNotifyContext *context = nqueue->context;
94  GParamSpec *pspecs_mem[16], **pspecs, **free_me = NULL;
95  GSList *slist;
96  guint n_pspecs = 0;
97
98  g_return_if_fail (nqueue->freeze_count > 0);
99
100  nqueue->freeze_count--;
101  if (nqueue->freeze_count)
102    return;
103  g_return_if_fail (object->ref_count > 0);
104
105  pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;
106  /* set first entry to NULL since it's checked unconditionally */
107  pspecs[0] = NULL;
108  for (slist = nqueue->pspecs; slist; slist = slist->next)
109    {
110      GParamSpec *pspec = slist->data;
111      guint i = 0;
112
113      /* dedup, make pspecs in the list unique */
114    redo_dedup_check:
115      if (pspecs[i] == pspec)
116	continue;
117      if (++i < n_pspecs)
118	goto redo_dedup_check;
119
120      pspecs[n_pspecs++] = pspec;
121    }
122  g_datalist_id_set_data (&object->qdata, context->quark_notify_queue, NULL);
123
124  if (n_pspecs)
125    context->dispatcher (object, n_pspecs, pspecs);
126  g_free (free_me);
127}
128
129static inline void
130g_object_notify_queue_clear (GObject            *object,
131			     GObjectNotifyQueue *nqueue)
132{
133  g_return_if_fail (nqueue->freeze_count > 0);
134
135  g_slist_free (nqueue->pspecs);
136  nqueue->pspecs = NULL;
137  nqueue->n_pspecs = 0;
138}
139
140static inline void
141g_object_notify_queue_add (GObject            *object,
142			   GObjectNotifyQueue *nqueue,
143			   GParamSpec	      *pspec)
144{
145  if (pspec->flags & G_PARAM_READABLE)
146    {
147      GParamSpec *redirect;
148
149      g_return_if_fail (nqueue->n_pspecs < 65535);
150
151      redirect = g_param_spec_get_redirect_target (pspec);
152      if (redirect)
153	pspec = redirect;
154
155      /* we do the deduping in _thaw */
156      nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);
157      nqueue->n_pspecs++;
158    }
159}
160
161static inline GObjectNotifyQueue*
162g_object_notify_queue_from_object (GObject              *object,
163				   GObjectNotifyContext *context)
164{
165  return g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
166}
167
168
169G_END_DECLS
170
171#endif /* __G_OBJECT_NOTIFY_QUEUE_H__ */
172