[kdbus] KDBUS_ITEM_PAYLOAD_OFF items are (once again) relative to msg header

[platform/upstream/glib.git] / gobject / gobjectnotifyqueue.c

diff --git a/gobject/gobjectnotifyqueue.c b/gobject/gobjectnotifyqueue.c
index 60c1c28..db2aa46 100644 (file)
--- a/gobject/gobjectnotifyqueue.c
+++ b/gobject/gobjectnotifyqueue.c
@@ -12,15 +12,21 @@
  * 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.
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
+
+/* 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>
+#include <string.h> /* memset */
+
+#include <glib-object.h>
 
 G_BEGIN_DECLS
 
@@ -46,11 +52,9 @@ struct _GObjectNotifyQueue
   GSList               *pspecs;
   guint16               n_pspecs;
   guint16               freeze_count;
-  /* currently, this structure abuses the GList allocation chain and thus
-   * must be <= sizeof (GList)
-   */
 };
 
+G_LOCK_DEFINE_STATIC(notify_lock);
 
 /* --- functions --- */
 static void
@@ -59,7 +63,7 @@ g_object_notify_queue_free (gpointer data)
   GObjectNotifyQueue *nqueue = data;
 
   g_slist_free (nqueue->pspecs);
-  g_list_free_1 ((void*) nqueue);
+  g_slice_free (GObjectNotifyQueue, nqueue);
 }
 
 static inline GObjectNotifyQueue*
@@ -68,18 +72,24 @@ g_object_notify_queue_freeze (GObject                  *object,
 {
   GObjectNotifyQueue *nqueue;
 
+  G_LOCK(notify_lock);
   nqueue = g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
   if (!nqueue)
     {
-      nqueue = (void*) g_list_alloc ();
-      memset (nqueue, 0, sizeof (*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);
     }
 
-  g_return_val_if_fail (nqueue->freeze_count < 65535, nqueue);
-  nqueue->freeze_count++;
+  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;
 }
@@ -94,31 +104,34 @@ g_object_notify_queue_thaw (GObject            *object,
   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)
+  if (nqueue->freeze_count) {
+    G_UNLOCK(notify_lock);
     return;
-  g_return_if_fail (object->ref_count > 0);
+  }
 
   pspecs = nqueue->n_pspecs > 16 ? free_me = g_new (GParamSpec*, nqueue->n_pspecs) : pspecs_mem;
-  /* set first entry to NULL since it's checked unconditionally */
-  pspecs[0] = NULL;
+
   for (slist = nqueue->pspecs; slist; slist = slist->next)
     {
-      GParamSpec *pspec = slist->data;
-      guint i = 0;
-
-      /* dedup, make pspecs in the list unique */
-    redo_dedup_check:
-      if (pspecs[i] == pspec)
-       continue;
-      if (++i < n_pspecs)
-       goto redo_dedup_check;
-
-      pspecs[n_pspecs++] = pspec;
+      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);
@@ -130,9 +143,13 @@ g_object_notify_queue_clear (GObject            *object,
 {
   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
@@ -144,6 +161,8 @@ g_object_notify_queue_add (GObject            *object,
     {
       GParamSpec *redirect;
 
+      G_LOCK(notify_lock);
+
       g_return_if_fail (nqueue->n_pspecs < 65535);
 
       redirect = g_param_spec_get_redirect_target (pspec);
@@ -151,19 +170,28 @@ g_object_notify_queue_add (GObject            *object,
        pspec = redirect;
            
       /* we do the deduping in _thaw */
-      nqueue->pspecs = g_slist_prepend (nqueue->pspecs, pspec);
-      nqueue->n_pspecs++;
+      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)
+                                   GObjectNotifyContext *context)
 {
   return g_datalist_id_get_data (&object->qdata, context->quark_notify_queue);
 }
 
-
 G_END_DECLS
 
 #endif /* __G_OBJECT_NOTIFY_QUEUE_H__ */