event: Add running-time-offset field to all events

Events passing through #GstPads that have a running time
offset set via gst_pad_set_offset() will get their offset
adjusted according to the pad's offset.

If the event contains any information that related to the
running time, this information will need to be updated
before usage with this offset.

docs/gst/gstreamer-sections.txt

@@ -1055,6 +1055,9 @@ gst_event_has_name
 gst_event_get_seqnum
 gst_event_set_seqnum
 
+gst_event_get_running_time_offset
+gst_event_set_running_time_offset
+
 gst_event_new_flush_start
 gst_event_new_flush_stop
 gst_event_parse_flush_stop

gst/gstevent.c

@@ -90,6 +90,7 @@ typedef struct
   GstEvent event;
 
   GstStructure *structure;
+  gint64 running_time_offset;
 } GstEventImpl;
 
 #define GST_EVENT_STRUCTURE(e)  (((GstEventImpl *)(e))->structure)
@@ -251,6 +252,10 @@ _gst_event_copy (GstEvent * event)
   } else {
     GST_EVENT_STRUCTURE (copy) = NULL;
   }
+
+  ((GstEventImpl *) copy)->running_time_offset =
+      ((GstEventImpl *) event)->running_time_offset;
+
   return GST_EVENT_CAST (copy);
 }
 
@@ -264,6 +269,7 @@ gst_event_init (GstEventImpl * event, GstEventType type)
   GST_EVENT_TYPE (event) = type;
   GST_EVENT_TIMESTAMP (event) = GST_CLOCK_TIME_NONE;
   GST_EVENT_SEQNUM (event) = gst_util_seqnum_next ();
+  event->running_time_offset = 0;
 }
 
 
@@ -442,6 +448,54 @@ gst_event_set_seqnum (GstEvent * event, guint32 seqnum)
   GST_EVENT_SEQNUM (event) = seqnum;
 }
 
+/**
+ * gst_event_get_running_time_offset:
+ * @event: A #GstEvent.
+ *
+ * Retrieve the accumulated running time offset of the event.
+ *
+ * Events passing through #GstPads that have a running time
+ * offset set via gst_pad_set_offset() will get their offset
+ * adjusted according to the pad's offset.
+ *
+ * If the event contains any information that related to the
+ * running time, this information will need to be updated
+ * before usage with this offset.
+ *
+ * Returns: The event's running time offset
+ *
+ * MT safe.
+ *
+ * Since: 1.4
+ */
+gint64
+gst_event_get_running_time_offset (GstEvent * event)
+{
+  g_return_val_if_fail (GST_IS_EVENT (event), 0);
+
+  return ((GstEventImpl *) event)->running_time_offset;
+}
+
+/**
+ * gst_event_set_running_time_offset:
+ * @event: A #GstEvent.
+ * @offset: A the new running time offset
+ *
+ * Set the running time offset of a event. See
+ * gst_event_get_running_time_offset() for more information.
+ *
+ * MT safe.
+ *
+ * Since: 1.4
+ */
+void
+gst_event_set_running_time_offset (GstEvent * event, gint64 offset)
+{
+  g_return_if_fail (GST_IS_EVENT (event));
+
+  ((GstEventImpl *) event)->running_time_offset = offset;
+}
+
 /**
  * gst_event_new_flush_start:
  *

gst/gstevent.h

@@ -482,6 +482,10 @@ gboolean        gst_event_has_name              (GstEvent *event, const gchar *n
 guint32         gst_event_get_seqnum            (GstEvent *event);
 void            gst_event_set_seqnum            (GstEvent *event, guint32 seqnum);
 
+/* accumulated pad offsets for the event */
+gint64          gst_event_get_running_time_offset (GstEvent *event);
+void            gst_event_set_running_time_offset (GstEvent *event, gint64 offset);
+
 /* Stream start event */
 GstEvent *      gst_event_new_stream_start      (const gchar *stream_id) G_GNUC_MALLOC;
 void            gst_event_parse_stream_start    (GstEvent *event, const gchar **stream_id);

win32/common/libgstreamer.def

@@ -510,6 +510,7 @@ EXPORTS
 	gst_element_unlink_pads
 	gst_error_get_message
 	gst_event_copy_segment
+	gst_event_get_running_time_offset
 	gst_event_get_seqnum
 	gst_event_get_structure
 	gst_event_get_type
@@ -552,6 +553,7 @@ EXPORTS
 	gst_event_parse_toc
 	gst_event_parse_toc_select
 	gst_event_set_group_id
+	gst_event_set_running_time_offset
 	gst_event_set_seqnum
 	gst_event_set_stream_flags
 	gst_event_type_flags_get_type