glib/gobject/gobjectnotifyqueue.c

200 lines
5.5 KiB
C
Raw Normal View History

/* 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.
*/
/* WARNING:
*
* This file is INSTALLED and other projects (outside of glib)
* #include its contents.
*/
#ifndef __G_OBJECT_NOTIFY_QUEUE_H__
#define __G_OBJECT_NOTIFY_QUEUE_H__
#include <string.h> /* memset */
#include <glib-object.h>
G_BEGIN_DECLS
/* --- typedefs --- */
typedef struct _GObjectNotifyContext GObjectNotifyContext;
typedef struct _GObjectNotifyQueue GObjectNotifyQueue;
typedef void (*GObjectNotifyQueueDispatcher) (GObject *object,
guint n_pspecs,
GParamSpec **pspecs);
/* --- structures --- */
struct _GObjectNotifyContext
{
GQuark quark_notify_queue;
GObjectNotifyQueueDispatcher dispatcher;
GTrashStack *_nqueue_trash; /* unused */
};
struct _GObjectNotifyQueue
{
GObjectNotifyContext *context;
GSList *pspecs;
guint16 n_pspecs;
guint16 freeze_count;
};
G_LOCK_DEFINE_STATIC(notify_lock);
/* --- functions --- */
static void
g_object_notify_queue_free (gpointer data)
{
GObjectNotifyQueue *nqueue = data;
g_slist_free (nqueue->pspecs);
g_slice_free (GObjectNotifyQueue, nqueue);
}
static inline GObjectNotifyQueue*
g_object_notify_queue_freeze (GObject *object,
GObjectNotifyContext *context)
{
GObjectNotifyQueue *nqueue;
G_LOCK(notify_lock);
nqueue = g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
if (!nqueue)
{
nqueue = g_slice_new0 (GObjectNotifyQueue);
nqueue->context = context;
g_datalist_id_set_data_full (&object->qdata, context->quark_notify_queue,
nqueue, g_object_notify_queue_free);
}
if (nqueue->freeze_count >= 65535)
g_critical("Free queue for %s (%p) is larger than 65535,"
" called g_object_freeze_notify() too often."
" Forgot to call g_object_thaw_notify() or infinite loop",
G_OBJECT_TYPE_NAME (object), object);
else
nqueue->freeze_count++;
G_UNLOCK(notify_lock);
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);
g_return_if_fail (g_atomic_int_get(&object->ref_count) > 0);
G_LOCK(notify_lock);
/* Just make sure we never get into some nasty race condition */
if (G_UNLIKELY(nqueue->freeze_count == 0)) {
G_UNLOCK(notify_lock);
g_warning ("%s: property-changed notification for %s(%p) is not frozen",
G_STRFUNC, G_OBJECT_TYPE_NAME (object), object);
return;
}
nqueue->freeze_count--;
if (nqueue->freeze_count) {
G_UNLOCK(notify_lock);
return;
}
pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;
for (slist = nqueue->pspecs; slist; slist = slist->next)
{
pspecs[n_pspecs++] = slist->data;
}
g_datalist_id_set_data (&object->qdata, context->quark_notify_queue, NULL);
G_UNLOCK(notify_lock);
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_LOCK(notify_lock);
g_slist_free (nqueue->pspecs);
nqueue->pspecs = NULL;
nqueue->n_pspecs = 0;
G_UNLOCK(notify_lock);
}
static inline void
g_object_notify_queue_add (GObject *object,
GObjectNotifyQueue *nqueue,
GParamSpec *pspec)
{
if (pspec->flags & G_PARAM_READABLE)
{
GParamSpec *redirect;
G_LOCK(notify_lock);
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 */
if (g_slist_find (nqueue->pspecs, pspec) == NULL)
{
nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);
nqueue->n_pspecs++;
}
G_UNLOCK(notify_lock);
}
}
/* NB: This function is not threadsafe, do not ever use it if
* you need a threadsafe notify queue.
* Use g_object_notify_queue_freeze() to acquire the queue and
* g_object_notify_queue_thaw() after you are done instead.
*/
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__ */