X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=gst%2Fgstmessage.c;h=9a790d381b49a725fe22e41a350f416429feb517;hb=e10266e3f3cf9b05b69198b1ac6faa9a62840e30;hp=91881bb08cfc72cdfbf98c9e0602a42221cc03fc;hpb=2d7f9cfe92de5fe8faa767d9261d3adb55c7f5e2;p=platform%2Fupstream%2Fgstreamer.git

diff --git a/gst/gstmessage.c b/gst/gstmessage.c
index 91881bb..9a790d3 100644
--- a/gst/gstmessage.c
+++ b/gst/gstmessage.c
@@ -15,8 +15,8 @@
  *
  * You should have received a copy of the GNU Library 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.
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
  */
 
 /**
@@ -32,20 +32,14 @@
  *
  * Messages are posted by objects in the pipeline and are passed to the
  * application using the #GstBus.
-
- * The basic use pattern of posting a message on a #GstBus is as follows:
  *
- * <example>
- * <title>Posting a #GstMessage</title>
- *   <programlisting>
- *    gst_bus_post (bus, gst_message_new_eos());
- *   </programlisting>
- * </example>
+ * The basic use pattern of posting a message on a #GstBus is as follows:
+ * |[
+ *   gst_bus_post (bus, gst_message_new_eos());
+ * ]|
  *
  * A #GstElement usually posts messages on the bus provided by the parent
  * container using gst_element_post_message().
- *
- * Last reviewed on 2005-11-09 (0.9.4)
  */
 
 
@@ -67,7 +61,7 @@ typedef struct
   GstStructure *structure;
 } GstMessageImpl;
 
-#define GST_MESSAGE_STRUCTURE(m) (((GstMessageImpl *)(m))->structure)
+#define GST_MESSAGE_STRUCTURE(m)  (((GstMessageImpl *)(m))->structure)
 
 typedef struct
 {
@@ -96,7 +90,7 @@ static GstMessageQuarks message_quarks[] = {
   {GST_MESSAGE_ELEMENT, "element", 0},
   {GST_MESSAGE_SEGMENT_START, "segment-start", 0},
   {GST_MESSAGE_SEGMENT_DONE, "segment-done", 0},
-  {GST_MESSAGE_DURATION, "duration", 0},
+  {GST_MESSAGE_DURATION_CHANGED, "duration-changed", 0},
   {GST_MESSAGE_LATENCY, "latency", 0},
   {GST_MESSAGE_ASYNC_START, "async-start", 0},
   {GST_MESSAGE_ASYNC_DONE, "async-done", 0},
@@ -104,6 +98,13 @@ static GstMessageQuarks message_quarks[] = {
   {GST_MESSAGE_STEP_START, "step-start", 0},
   {GST_MESSAGE_QOS, "qos", 0},
   {GST_MESSAGE_PROGRESS, "progress", 0},
+  {GST_MESSAGE_TOC, "toc", 0},
+  {GST_MESSAGE_RESET_TIME, "reset-time", 0},
+  {GST_MESSAGE_STREAM_START, "stream-start", 0},
+  {GST_MESSAGE_NEED_CONTEXT, "need-context", 0},
+  {GST_MESSAGE_HAVE_CONTEXT, "have-context", 0},
+  {GST_MESSAGE_DEVICE_ADDED, "device-added", 0},
+  {GST_MESSAGE_DEVICE_REMOVED, "device-removed", 0},
   {0, NULL, 0}
 };
 
@@ -185,7 +186,7 @@ _gst_message_free (GstMessage * message)
     GST_MESSAGE_SRC (message) = NULL;
   }
 
-  if (message->lock) {
+  if (message->lock.p) {
     GST_MESSAGE_LOCK (message);
     GST_MESSAGE_SIGNAL (message);
     GST_MESSAGE_UNLOCK (message);
@@ -197,9 +198,13 @@ _gst_message_free (GstMessage * message)
     gst_structure_free (structure);
   }
 
-  g_slice_free1 (GST_MINI_OBJECT_SIZE (message), message);
+  g_slice_free1 (sizeof (GstMessageImpl), message);
 }
 
+static void
+gst_message_init (GstMessageImpl * message, GstMessageType type,
+    GstObject * src);
+
 static GstMessage *
 _gst_message_copy (GstMessage * message)
 {
@@ -212,34 +217,41 @@ _gst_message_copy (GstMessage * message)
 
   copy = g_slice_new0 (GstMessageImpl);
 
-  gst_mini_object_init (GST_MINI_OBJECT_CAST (copy),
-      _gst_message_type, sizeof (GstMessageImpl));
-
-  copy->message.mini_object.copy =
-      (GstMiniObjectCopyFunction) _gst_message_copy;
-  copy->message.mini_object.free =
-      (GstMiniObjectFreeFunction) _gst_message_free;
+  gst_message_init (copy, GST_MESSAGE_TYPE (message),
+      GST_MESSAGE_SRC (message));
 
-  GST_MESSAGE_TYPE (copy) = GST_MESSAGE_TYPE (message);
   GST_MESSAGE_TIMESTAMP (copy) = GST_MESSAGE_TIMESTAMP (message);
   GST_MESSAGE_SEQNUM (copy) = GST_MESSAGE_SEQNUM (message);
-  if (GST_MESSAGE_SRC (message)) {
-    GST_MESSAGE_SRC (copy) = gst_object_ref (GST_MESSAGE_SRC (message));
-  }
-
-  GST_MESSAGE_GET_LOCK (copy) = GST_MESSAGE_GET_LOCK (message);
-  GST_MESSAGE_COND (copy) = GST_MESSAGE_COND (message);
 
   structure = GST_MESSAGE_STRUCTURE (message);
   if (structure) {
-    copy->structure = gst_structure_copy (structure);
-    gst_structure_set_parent_refcount (copy->structure,
+    GST_MESSAGE_STRUCTURE (copy) = gst_structure_copy (structure);
+    gst_structure_set_parent_refcount (GST_MESSAGE_STRUCTURE (copy),
         &copy->message.mini_object.refcount);
+  } else {
+    GST_MESSAGE_STRUCTURE (copy) = NULL;
   }
 
   return GST_MESSAGE_CAST (copy);
 }
 
+static void
+gst_message_init (GstMessageImpl * message, GstMessageType type,
+    GstObject * src)
+{
+  gst_mini_object_init (GST_MINI_OBJECT_CAST (message), 0, _gst_message_type,
+      (GstMiniObjectCopyFunction) _gst_message_copy, NULL,
+      (GstMiniObjectFreeFunction) _gst_message_free);
+
+  GST_MESSAGE_TYPE (message) = type;
+  if (src)
+    gst_object_ref (src);
+  GST_MESSAGE_SRC (message) = src;
+  GST_MESSAGE_TIMESTAMP (message) = GST_CLOCK_TIME_NONE;
+  GST_MESSAGE_SEQNUM (message) = gst_util_seqnum_next ();
+}
+
+
 /**
  * gst_message_new_custom:
  * @type: The #GstMessageType to distinguish messages
@@ -249,7 +261,7 @@ _gst_message_copy (GstMessage * message)
  *
  * Create a new custom-typed message. This can be used for anything not
  * handled by other message-specific functions to pass a message to the
- * app. The structure field can be NULL.
+ * app. The structure field can be %NULL.
  *
  * Returns: (transfer full): The new message.
  *
@@ -263,32 +275,29 @@ gst_message_new_custom (GstMessageType type, GstObject * src,
 
   message = g_slice_new0 (GstMessageImpl);
 
-  gst_mini_object_init (GST_MINI_OBJECT_CAST (message),
-      _gst_message_type, sizeof (GstMessageImpl));
-
-  message->message.mini_object.copy =
-      (GstMiniObjectCopyFunction) _gst_message_copy;
-  message->message.mini_object.free =
-      (GstMiniObjectFreeFunction) _gst_message_free;
-
   GST_CAT_LOG (GST_CAT_MESSAGE, "source %s: creating new message %p %s",
       (src ? GST_OBJECT_NAME (src) : "NULL"), message,
       gst_message_type_get_name (type));
 
-  GST_MESSAGE_TYPE (message) = type;
-  if (src)
-    gst_object_ref (src);
-  GST_MESSAGE_SRC (message) = src;
-  GST_MESSAGE_TIMESTAMP (message) = GST_CLOCK_TIME_NONE;
-  GST_MESSAGE_SEQNUM (message) = gst_util_seqnum_next ();
-
   if (structure) {
-    gst_structure_set_parent_refcount (structure,
-        &message->message.mini_object.refcount);
+    /* structure must not have a parent */
+    if (!gst_structure_set_parent_refcount (structure,
+            &message->message.mini_object.refcount))
+      goto had_parent;
   }
-  message->structure = structure;
+  gst_message_init (message, type, src);
+
+  GST_MESSAGE_STRUCTURE (message) = structure;
 
   return GST_MESSAGE_CAST (message);
+
+  /* ERRORS */
+had_parent:
+  {
+    g_slice_free1 (sizeof (GstMessageImpl), message);
+    g_warning ("structure is already owned by another object");
+    return NULL;
+  }
 }
 
 /**
@@ -311,8 +320,6 @@ gst_message_new_custom (GstMessageType type, GstObject * src,
  * Returns: The message's sequence number.
  *
  * MT safe.
- *
- * Since: 0.10.22
  */
 guint32
 gst_message_get_seqnum (GstMessage * message)
@@ -334,8 +341,6 @@ gst_message_get_seqnum (GstMessage * message)
  * for more information.
  *
  * MT safe.
- *
- * Since: 0.10.22
  */
 void
 gst_message_set_seqnum (GstMessage * message, guint32 seqnum)
@@ -375,7 +380,7 @@ gst_message_new_eos (GstObject * src)
  *
  * Create a new error message. The message will copy @error and
  * @debug. This message is posted by element when a fatal event
- * occured. The pipeline will probably (partially) stop. The application
+ * occurred. The pipeline will probably (partially) stop. The application
  * receiving this message should stop the pipeline.
  *
  * Returns: (transfer full): the new error message.
@@ -389,7 +394,7 @@ gst_message_new_error (GstObject * src, GError * error, const gchar * debug)
   GstStructure *structure;
 
   structure = gst_structure_new_id (GST_QUARK (MESSAGE_ERROR),
-      GST_QUARK (GERROR), GST_TYPE_G_ERROR, error,
+      GST_QUARK (GERROR), G_TYPE_ERROR, error,
       GST_QUARK (DEBUG), G_TYPE_STRING, debug, NULL);
   message = gst_message_new_custom (GST_MESSAGE_ERROR, src, structure);
 
@@ -416,7 +421,7 @@ gst_message_new_warning (GstObject * src, GError * error, const gchar * debug)
   GstStructure *structure;
 
   structure = gst_structure_new_id (GST_QUARK (MESSAGE_WARNING),
-      GST_QUARK (GERROR), GST_TYPE_G_ERROR, error,
+      GST_QUARK (GERROR), G_TYPE_ERROR, error,
       GST_QUARK (DEBUG), G_TYPE_STRING, debug, NULL);
   message = gst_message_new_custom (GST_MESSAGE_WARNING, src, structure);
 
@@ -435,8 +440,6 @@ gst_message_new_warning (GstObject * src, GError * error, const gchar * debug)
  * MT safe.
  *
  * Returns: (transfer full): the new info message.
- *
- * Since: 0.10.12
  */
 GstMessage *
 gst_message_new_info (GstObject * src, GError * error, const gchar * debug)
@@ -445,7 +448,7 @@ gst_message_new_info (GstObject * src, GError * error, const gchar * debug)
   GstStructure *structure;
 
   structure = gst_structure_new_id (GST_QUARK (MESSAGE_INFO),
-      GST_QUARK (GERROR), GST_TYPE_G_ERROR, error,
+      GST_QUARK (GERROR), G_TYPE_ERROR, error,
       GST_QUARK (DEBUG), G_TYPE_STRING, debug, NULL);
   message = gst_message_new_custom (GST_MESSAGE_INFO, src, structure);
 
@@ -467,13 +470,17 @@ gst_message_new_info (GstObject * src, GError * error, const gchar * debug)
 GstMessage *
 gst_message_new_tag (GstObject * src, GstTagList * tag_list)
 {
+  GstStructure *s;
   GstMessage *message;
+  GValue val = G_VALUE_INIT;
 
-  g_return_val_if_fail (GST_IS_STRUCTURE (tag_list), NULL);
-
-  message =
-      gst_message_new_custom (GST_MESSAGE_TAG, src, (GstStructure *) tag_list);
+  g_return_val_if_fail (GST_IS_TAG_LIST (tag_list), NULL);
 
+  s = gst_structure_new_id_empty (GST_QUARK (MESSAGE_TAG));
+  g_value_init (&val, GST_TYPE_TAG_LIST);
+  g_value_take_boxed (&val, tag_list);
+  gst_structure_id_take_value (s, GST_QUARK (TAGLIST), &val);
+  message = gst_message_new_custom (GST_MESSAGE_TAG, src, s);
   return message;
 }
 
@@ -491,29 +498,29 @@ gst_message_new_tag (GstObject * src, GstTagList * tag_list)
  * The application must be prepared to receive BUFFERING messages in the
  * PREROLLING state and may only set the pipeline to PLAYING after receiving a
  * message with @percent set to 100, which can happen after the pipeline
- * completed prerolling. 
+ * completed prerolling.
  *
  * MT safe.
  *
  * Returns: (transfer full): The new buffering message.
- *
- * Since: 0.10.11
  */
 GstMessage *
 gst_message_new_buffering (GstObject * src, gint percent)
 {
   GstMessage *message;
   GstStructure *structure;
+  gint64 buffering_left;
 
   g_return_val_if_fail (percent >= 0 && percent <= 100, NULL);
 
+  buffering_left = (percent == 100 ? 0 : -1);
+
   structure = gst_structure_new_id (GST_QUARK (MESSAGE_BUFFERING),
       GST_QUARK (BUFFER_PERCENT), G_TYPE_INT, percent,
       GST_QUARK (BUFFERING_MODE), GST_TYPE_BUFFERING_MODE, GST_BUFFERING_STREAM,
       GST_QUARK (AVG_IN_RATE), G_TYPE_INT, -1,
       GST_QUARK (AVG_OUT_RATE), G_TYPE_INT, -1,
-      GST_QUARK (BUFFERING_LEFT), G_TYPE_INT64, G_GINT64_CONSTANT (-1),
-      GST_QUARK (ESTIMATED_TOTAL), G_TYPE_INT64, G_GINT64_CONSTANT (-1), NULL);
+      GST_QUARK (BUFFERING_LEFT), G_TYPE_INT64, buffering_left, NULL);
   message = gst_message_new_custom (GST_MESSAGE_BUFFERING, src, structure);
 
   return message;
@@ -540,7 +547,7 @@ gst_message_new_state_changed (GstObject * src,
   GstMessage *message;
   GstStructure *structure;
 
-  structure = gst_structure_new_id (GST_QUARK (MESSAGE_STATE),
+  structure = gst_structure_new_id (GST_QUARK (MESSAGE_STATE_CHANGED),
       GST_QUARK (OLD_STATE), GST_TYPE_STATE, (gint) oldstate,
       GST_QUARK (NEW_STATE), GST_TYPE_STATE, (gint) newstate,
       GST_QUARK (PENDING_STATE), GST_TYPE_STATE, (gint) pending, NULL);
@@ -575,7 +582,7 @@ gst_message_new_state_dirty (GstObject * src)
  * gst_message_new_clock_provide:
  * @src: (transfer none): the object originating the message.
  * @clock: (transfer none): the clock it provides
- * @ready: TRUE if the sender can provide a clock
+ * @ready: %TRUE if the sender can provide a clock
  *
  * Create a clock provide message. This message is posted whenever an
  * element is ready to provide a clock or lost its ability to provide
@@ -638,7 +645,7 @@ gst_message_new_clock_lost (GstObject * src, GstClock * clock)
  * @clock: (transfer none): the new selected clock
  *
  * Create a new clock message. This message is posted whenever the
- * pipeline selectes a new clock for the pipeline.
+ * pipeline selects a new clock for the pipeline.
  *
  * Returns: (transfer full): The new new clock message.
  *
@@ -673,8 +680,6 @@ gst_message_new_new_clock (GstObject * src, GstClock * clock)
  * Returns: (transfer full): the new structure change message.
  *
  * MT safe.
- *
- * Since: 0.10.22.
  */
 GstMessage *
 gst_message_new_structure_change (GstObject * src, GstStructureChangeType type,
@@ -786,7 +791,7 @@ gst_message_new_application (GstObject * src, GstStructure * structure)
  * Create a new element-specific message. This is meant as a generic way of
  * allowing one-way communication from an element to an application, for example
  * "the firewire cable was unplugged". The format of the message should be
- * documented in the element's documentation. The structure field can be NULL.
+ * documented in the element's documentation. The structure field can be %NULL.
  *
  * Returns: (transfer full): The new element message.
  *
@@ -799,33 +804,28 @@ gst_message_new_element (GstObject * src, GstStructure * structure)
 }
 
 /**
- * gst_message_new_duration:
+ * gst_message_new_duration_changed:
  * @src: (transfer none): The object originating the message.
- * @format: The format of the duration
- * @duration: The new duration 
  *
- * Create a new duration message. This message is posted by elements that
- * know the duration of a stream in a specific format. This message
+ * Create a new duration changed message. This message is posted by elements
+ * that know the duration of a stream when the duration changes. This message
  * is received by bins and is used to calculate the total duration of a
  * pipeline. Elements may post a duration message with a duration of
  * GST_CLOCK_TIME_NONE to indicate that the duration has changed and the 
  * cached duration should be discarded. The new duration can then be 
  * retrieved via a query.
  *
- * Returns: (transfer full): The new duration message.
+ * Returns: (transfer full): The new duration-changed message.
  *
  * MT safe.
  */
 GstMessage *
-gst_message_new_duration (GstObject * src, GstFormat format, gint64 duration)
+gst_message_new_duration_changed (GstObject * src)
 {
   GstMessage *message;
-  GstStructure *structure;
 
-  structure = gst_structure_new_id (GST_QUARK (MESSAGE_DURATION),
-      GST_QUARK (FORMAT), GST_TYPE_FORMAT, format,
-      GST_QUARK (DURATION), G_TYPE_INT64, duration, NULL);
-  message = gst_message_new_custom (GST_MESSAGE_DURATION, src, structure);
+  message = gst_message_new_custom (GST_MESSAGE_DURATION_CHANGED, src,
+      gst_structure_new_id_empty (GST_QUARK (MESSAGE_DURATION_CHANGED)));
 
   return message;
 }
@@ -853,24 +853,26 @@ gst_message_new_async_start (GstObject * src)
 /**
  * gst_message_new_async_done:
  * @src: (transfer none): The object originating the message.
- * @reset_time: if the running_time should be reset
+ * @running_time: the desired running_time
  *
  * The message is posted when elements completed an ASYNC state change.
- * @reset_time is set to TRUE when the element requests a new running_time
- * before going to PLAYING.
+ * @running_time contains the time of the desired running_time when this
+ * elements goes to PLAYING. A value of #GST_CLOCK_TIME_NONE for @running_time
+ * means that the element has no clock interaction and thus doesn't care about
+ * the running_time of the pipeline.
  *
  * Returns: (transfer full): The new async_done message.
  *
  * MT safe.
  */
 GstMessage *
-gst_message_new_async_done (GstObject * src, gboolean reset_time)
+gst_message_new_async_done (GstObject * src, GstClockTime running_time)
 {
   GstMessage *message;
   GstStructure *structure;
 
   structure = gst_structure_new_id (GST_QUARK (MESSAGE_ASYNC_DONE),
-      GST_QUARK (RESET_TIME), G_TYPE_BOOLEAN, reset_time, NULL);
+      GST_QUARK (RUNNING_TIME), G_TYPE_UINT64, running_time, NULL);
   message = gst_message_new_custom (GST_MESSAGE_ASYNC_DONE, src, structure);
 
   return message;
@@ -886,8 +888,6 @@ gst_message_new_async_done (GstObject * src, gboolean reset_time)
  * Returns: (transfer full): The new latency message.
  *
  * MT safe.
- *
- * Since: 0.10.12
  */
 GstMessage *
 gst_message_new_latency (GstObject * src)
@@ -908,11 +908,9 @@ gst_message_new_latency (GstObject * src)
  * changed. A typical use case would be an audio server that wants to pause the
  * pipeline because a higher priority stream is being played.
  *
- * Returns: (transfer full): the new requst state message.
+ * Returns: (transfer full): the new request state message.
  *
  * MT safe.
- *
- * Since: 0.10.23
  */
 GstMessage *
 gst_message_new_request_state (GstObject * src, GstState state)
@@ -956,8 +954,6 @@ gst_message_get_structure (GstMessage * message)
  * check the name of a custom message.
  *
  * Returns: %TRUE if @name matches the name of the message structure.
- *
- * Since: 0.10.20
  */
 gboolean
 gst_message_has_name (GstMessage * message, const gchar * name)
@@ -991,7 +987,7 @@ gst_message_has_name (GstMessage * message, const gchar * name)
  *       gst_message_parse_tag (msg, &amp;tags);
  *       g_print ("Got tags from element %s\n", GST_OBJECT_NAME (msg->src));
  *       handle_tags (tags);
- *       gst_tag_list_free (tags);
+ *       gst_tag_list_unref (tags);
  *       break;
  *     }
  *     ...
@@ -1004,16 +1000,12 @@ gst_message_has_name (GstMessage * message, const gchar * name)
 void
 gst_message_parse_tag (GstMessage * message, GstTagList ** tag_list)
 {
-  GstStructure *ret;
-
   g_return_if_fail (GST_IS_MESSAGE (message));
   g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_TAG);
   g_return_if_fail (tag_list != NULL);
 
-  ret = gst_structure_copy (GST_MESSAGE_STRUCTURE (message));
-  gst_structure_remove_field (ret, "source-pad");
-
-  *tag_list = (GstTagList *) ret;
+  gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+      GST_QUARK (TAGLIST), GST_TYPE_TAG_LIST, tag_list, NULL);
 }
 
 /**
@@ -1025,8 +1017,6 @@ gst_message_parse_tag (GstMessage * message, GstTagList ** tag_list)
  * gst_message_new_buffering().
  *
  * MT safe.
- *
- * Since: 0.10.11
  */
 void
 gst_message_parse_buffering (GstMessage * message, gint * percent)
@@ -1049,8 +1039,6 @@ gst_message_parse_buffering (GstMessage * message, gint * percent)
  * @buffering_left: amount of buffering time left in milliseconds
  *
  * Configures the buffering stats values in @message.
- *
- * Since: 0.10.20
  */
 void
 gst_message_set_buffering_stats (GstMessage * message, GstBufferingMode mode,
@@ -1068,15 +1056,13 @@ gst_message_set_buffering_stats (GstMessage * message, GstBufferingMode mode,
 /**
  * gst_message_parse_buffering_stats:
  * @message: A valid #GstMessage of type GST_MESSAGE_BUFFERING.
- * @mode: (out) (allow-none): a buffering mode, or NULL
- * @avg_in: (out) (allow-none): the average input rate, or NULL
- * @avg_out: (out) (allow-none): the average output rate, or NULL
+ * @mode: (out) (allow-none): a buffering mode, or %NULL
+ * @avg_in: (out) (allow-none): the average input rate, or %NULL
+ * @avg_out: (out) (allow-none): the average output rate, or %NULL
  * @buffering_left: (out) (allow-none): amount of buffering time left in
- *     milliseconds, or NULL
+ *     milliseconds, or %NULL
  *
  * Extracts the buffering stats values from @message.
- *
- * Since: 0.10.20
  */
 void
 gst_message_parse_buffering_stats (GstMessage * message,
@@ -1107,9 +1093,9 @@ gst_message_parse_buffering_stats (GstMessage * message,
 /**
  * gst_message_parse_state_changed:
  * @message: a valid #GstMessage of type GST_MESSAGE_STATE_CHANGED
- * @oldstate: (out) (allow-none): the previous state, or NULL
- * @newstate: (out) (allow-none): the new (current) state, or NULL
- * @pending: (out) (allow-none): the pending (target) state, or NULL
+ * @oldstate: (out) (allow-none): the previous state, or %NULL
+ * @newstate: (out) (allow-none): the new (current) state, or %NULL
+ * @pending: (out) (allow-none): the pending (target) state, or %NULL
  *
  * Extracts the old and new states from the GstMessage.
  *
@@ -1162,8 +1148,8 @@ gst_message_parse_state_changed (GstMessage * message,
  * gst_message_parse_clock_provide:
  * @message: A valid #GstMessage of type GST_MESSAGE_CLOCK_PROVIDE.
  * @clock: (out) (allow-none) (transfer none): a pointer to  hold a clock
- *     object, or NULL
- * @ready: (out) (allow-none): a pointer to hold the ready flag, or NULL
+ *     object, or %NULL
+ * @ready: (out) (allow-none): a pointer to hold the ready flag, or %NULL
  *
  * Extracts the clock and ready flag from the GstMessage.
  * The clock object returned remains valid until the message is freed.
@@ -1262,8 +1248,6 @@ gst_message_parse_new_clock (GstMessage * message, GstClock ** clock)
  * Extracts the change type and completion status from the GstMessage.
  *
  * MT safe.
- *
- * Since: 0.10.22
  */
 void
 gst_message_parse_structure_change (GstMessage * message,
@@ -1297,7 +1281,7 @@ gst_message_parse_structure_change (GstMessage * message,
  * @message: A valid #GstMessage of type GST_MESSAGE_ERROR.
  * @gerror: (out) (allow-none) (transfer full): location for the GError
  * @debug: (out) (allow-none) (transfer full): location for the debug message,
- *     or NULL
+ *     or %NULL
  *
  * Extracts the GError and debug string from the GstMessage. The values returned
  * in the output arguments are copies; the caller must free them when done.
@@ -1328,28 +1312,12 @@ gst_message_parse_structure_change (GstMessage * message,
 void
 gst_message_parse_error (GstMessage * message, GError ** gerror, gchar ** debug)
 {
-  const GValue *error_gvalue;
-  GError *error_val;
-  GstStructure *structure;
-
   g_return_if_fail (GST_IS_MESSAGE (message));
   g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_ERROR);
 
-  structure = GST_MESSAGE_STRUCTURE (message);
-  error_gvalue = gst_structure_id_get_value (structure, GST_QUARK (GERROR));
-  g_return_if_fail (error_gvalue != NULL);
-  g_return_if_fail (G_VALUE_TYPE (error_gvalue) == GST_TYPE_G_ERROR);
-
-  error_val = (GError *) g_value_get_boxed (error_gvalue);
-  if (error_val)
-    *gerror = g_error_copy (error_val);
-  else
-    *gerror = NULL;
-
-  if (debug)
-    *debug =
-        g_value_dup_string (gst_structure_id_get_value (structure,
-            GST_QUARK (DEBUG)));
+  gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+      GST_QUARK (GERROR), G_TYPE_ERROR, gerror,
+      GST_QUARK (DEBUG), G_TYPE_STRING, debug, NULL);
 }
 
 /**
@@ -1357,7 +1325,7 @@ gst_message_parse_error (GstMessage * message, GError ** gerror, gchar ** debug)
  * @message: A valid #GstMessage of type GST_MESSAGE_WARNING.
  * @gerror: (out) (allow-none) (transfer full): location for the GError
  * @debug: (out) (allow-none) (transfer full): location for the debug message,
- *     or NULL
+ *     or %NULL
  *
  * Extracts the GError and debug string from the GstMessage. The values returned
  * in the output arguments are copies; the caller must free them when done.
@@ -1368,28 +1336,12 @@ void
 gst_message_parse_warning (GstMessage * message, GError ** gerror,
     gchar ** debug)
 {
-  const GValue *error_gvalue;
-  GError *error_val;
-  GstStructure *structure;
-
   g_return_if_fail (GST_IS_MESSAGE (message));
   g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_WARNING);
 
-  structure = GST_MESSAGE_STRUCTURE (message);
-  error_gvalue = gst_structure_id_get_value (structure, GST_QUARK (GERROR));
-  g_return_if_fail (error_gvalue != NULL);
-  g_return_if_fail (G_VALUE_TYPE (error_gvalue) == GST_TYPE_G_ERROR);
-
-  error_val = (GError *) g_value_get_boxed (error_gvalue);
-  if (error_val)
-    *gerror = g_error_copy (error_val);
-  else
-    *gerror = NULL;
-
-  if (debug)
-    *debug =
-        g_value_dup_string (gst_structure_id_get_value (structure,
-            GST_QUARK (DEBUG)));
+  gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+      GST_QUARK (GERROR), G_TYPE_ERROR, gerror,
+      GST_QUARK (DEBUG), G_TYPE_STRING, debug, NULL);
 }
 
 /**
@@ -1397,47 +1349,29 @@ gst_message_parse_warning (GstMessage * message, GError ** gerror,
  * @message: A valid #GstMessage of type GST_MESSAGE_INFO.
  * @gerror: (out) (allow-none) (transfer full): location for the GError
  * @debug: (out) (allow-none) (transfer full): location for the debug message,
- *     or NULL
+ *     or %NULL
  *
  * Extracts the GError and debug string from the GstMessage. The values returned
  * in the output arguments are copies; the caller must free them when done.
  *
  * MT safe.
- *
- * Since: 0.10.12
  */
 void
 gst_message_parse_info (GstMessage * message, GError ** gerror, gchar ** debug)
 {
-  const GValue *error_gvalue;
-  GError *error_val;
-  GstStructure *structure;
-
   g_return_if_fail (GST_IS_MESSAGE (message));
   g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_INFO);
 
-  structure = GST_MESSAGE_STRUCTURE (message);
-  error_gvalue = gst_structure_id_get_value (structure, GST_QUARK (GERROR));
-  g_return_if_fail (error_gvalue != NULL);
-  g_return_if_fail (G_VALUE_TYPE (error_gvalue) == GST_TYPE_G_ERROR);
-
-  error_val = (GError *) g_value_get_boxed (error_gvalue);
-  if (error_val)
-    *gerror = g_error_copy (error_val);
-  else
-    *gerror = NULL;
-
-  if (debug)
-    *debug =
-        g_value_dup_string (gst_structure_id_get_value (structure,
-            GST_QUARK (DEBUG)));
+  gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+      GST_QUARK (GERROR), G_TYPE_ERROR, gerror,
+      GST_QUARK (DEBUG), G_TYPE_STRING, debug, NULL);
 }
 
 /**
  * gst_message_parse_segment_start:
  * @message: A valid #GstMessage of type GST_MESSAGE_SEGMENT_START.
- * @format: (out): Result location for the format, or NULL
- * @position: (out): Result location for the position, or NULL
+ * @format: (out) (allow-none): Result location for the format, or %NULL
+ * @position: (out) (allow-none): Result location for the position, or %NULL
  *
  * Extracts the position and format from the segment start message.
  *
@@ -1466,10 +1400,10 @@ gst_message_parse_segment_start (GstMessage * message, GstFormat * format,
 /**
  * gst_message_parse_segment_done:
  * @message: A valid #GstMessage of type GST_MESSAGE_SEGMENT_DONE.
- * @format: (out): Result location for the format, or NULL
- * @position: (out): Result location for the position, or NULL
+ * @format: (out) (allow-none): Result location for the format, or %NULL
+ * @position: (out) (allow-none): Result location for the position, or %NULL
  *
- * Extracts the position and format from the segment start message.
+ * Extracts the position and format from the segment done message.
  *
  * MT safe.
  */
@@ -1494,49 +1428,16 @@ gst_message_parse_segment_done (GstMessage * message, GstFormat * format,
 }
 
 /**
- * gst_message_parse_duration:
- * @message: A valid #GstMessage of type GST_MESSAGE_DURATION.
- * @format: (out): Result location for the format, or NULL
- * @duration: (out): Result location for the duration, or NULL
- *
- * Extracts the duration and format from the duration message. The duration
- * might be GST_CLOCK_TIME_NONE, which indicates that the duration has
- * changed. Applications should always use a query to retrieve the duration
- * of a pipeline.
- *
- * MT safe.
- */
-void
-gst_message_parse_duration (GstMessage * message, GstFormat * format,
-    gint64 * duration)
-{
-  GstStructure *structure;
-
-  g_return_if_fail (GST_IS_MESSAGE (message));
-  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DURATION);
-
-  structure = GST_MESSAGE_STRUCTURE (message);
-  if (format)
-    *format = (GstFormat)
-        g_value_get_enum (gst_structure_id_get_value (structure,
-            GST_QUARK (FORMAT)));
-  if (duration)
-    *duration =
-        g_value_get_int64 (gst_structure_id_get_value (structure,
-            GST_QUARK (DURATION)));
-}
-
-/**
  * gst_message_parse_async_done:
  * @message: A valid #GstMessage of type GST_MESSAGE_ASYNC_DONE.
- * @reset_time: (out): Result location for the reset_time or NULL
+ * @running_time: (out) (allow-none): Result location for the running_time or %NULL
  *
- * Extract the reset_time from the async_done message.
+ * Extract the running_time from the async_done message.
  *
  * MT safe.
  */
 void
-gst_message_parse_async_done (GstMessage * message, gboolean * reset_time)
+gst_message_parse_async_done (GstMessage * message, GstClockTime * running_time)
 {
   GstStructure *structure;
 
@@ -1544,22 +1445,20 @@ gst_message_parse_async_done (GstMessage * message, gboolean * reset_time)
   g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_ASYNC_DONE);
 
   structure = GST_MESSAGE_STRUCTURE (message);
-  if (reset_time)
-    *reset_time =
-        g_value_get_boolean (gst_structure_id_get_value (structure,
-            GST_QUARK (RESET_TIME)));
+  if (running_time)
+    *running_time =
+        g_value_get_uint64 (gst_structure_id_get_value (structure,
+            GST_QUARK (RUNNING_TIME)));
 }
 
 /**
  * gst_message_parse_request_state:
  * @message: A valid #GstMessage of type GST_MESSAGE_REQUEST_STATE.
- * @state: (out): Result location for the requested state or NULL
+ * @state: (out) (allow-none): Result location for the requested state or %NULL
  *
  * Extract the requested state from the request_state message.
  *
  * MT safe.
- *
- * Since: 0.10.23
  */
 void
 gst_message_parse_request_state (GstMessage * message, GstState * state)
@@ -1588,8 +1487,6 @@ gst_message_parse_request_state (GstMessage * message, GstState * state)
  * Returns: (transfer full): the new stream status message.
  *
  * MT safe.
- *
- * Since: 0.10.24.
  */
 GstMessage *
 gst_message_new_stream_status (GstObject * src, GstStreamStatusType type,
@@ -1617,8 +1514,6 @@ gst_message_new_stream_status (GstObject * src, GstStreamStatusType type,
  * should thus not be unreffed.
  *
  * MT safe.
- *
- * Since: 0.10.24.
  */
 void
 gst_message_parse_stream_status (GstMessage * message,
@@ -1649,8 +1544,6 @@ gst_message_parse_stream_status (GstMessage * message,
  *
  * Configures the object handling the streaming thread. This is usually a
  * GstTask object but other objects might be added in the future.
- *
- * Since: 0.10.24
  */
 void
 gst_message_set_stream_status_object (GstMessage * message,
@@ -1674,8 +1567,6 @@ gst_message_set_stream_status_object (GstMessage * message,
  * Returns: a GValue containing the object that manages the streaming thread.
  * This object is usually of type GstTask but other types can be added in the
  * future. The object remains valid as long as @message is valid.
- *
- * Since: 0.10.24
  */
 const GValue *
 gst_message_get_stream_status_object (GstMessage * message)
@@ -1705,7 +1596,7 @@ gst_message_get_stream_status_object (GstMessage * message)
  * @eos: the step caused EOS
  *
  * This message is posted by elements when they complete a part, when @intermediate set
- * to TRUE, or a complete step operation.
+ * to %TRUE, or a complete step operation.
  *
  * @duration will contain the amount of time (in GST_FORMAT_TIME) of the stepped
  * @amount of media in format @format.
@@ -1713,8 +1604,6 @@ gst_message_get_stream_status_object (GstMessage * message)
  * Returns: (transfer full): the new step_done message.
  *
  * MT safe.
- *
- * Since: 0.10.24
  */
 GstMessage *
 gst_message_new_step_done (GstObject * src, GstFormat format, guint64 amount,
@@ -1751,8 +1640,6 @@ gst_message_new_step_done (GstObject * src, GstFormat format, guint64 amount,
  * Extract the values the step_done message.
  *
  * MT safe.
- *
- * Since: 0.10.24
  */
 void
 gst_message_parse_step_done (GstMessage * message, GstFormat * format,
@@ -1788,19 +1675,17 @@ gst_message_parse_step_done (GstMessage * message, GstFormat * format,
  * This message is posted by elements when they accept or activate a new step
  * event for @amount in @format. 
  *
- * @active is set to FALSE when the element accepted the new step event and has
+ * @active is set to %FALSE when the element accepted the new step event and has
  * queued it for execution in the streaming threads.
  *
- * @active is set to TRUE when the element has activated the step operation and
+ * @active is set to %TRUE when the element has activated the step operation and
  * is now ready to start executing the step in the streaming thread. After this
- * message is emited, the application can queue a new step operation in the
+ * message is emitted, the application can queue a new step operation in the
  * element.
  *
  * Returns: (transfer full): The new step_start message. 
  *
  * MT safe.
- *
- * Since: 0.10.24
  */
 GstMessage *
 gst_message_new_step_start (GstObject * src, gboolean active, GstFormat format,
@@ -1834,8 +1719,6 @@ gst_message_new_step_start (GstObject * src, gboolean active, GstFormat format,
  * Extract the values from step_start message.
  *
  * MT safe.
- *
- * Since: 0.10.24
  */
 void
 gst_message_parse_step_start (GstMessage * message, gboolean * active,
@@ -1883,8 +1766,6 @@ gst_message_parse_step_start (GstMessage * message, gboolean * active,
  * Returns: (transfer full): The new qos message.
  *
  * MT safe.
- *
- * Since: 0.10.29
  */
 GstMessage *
 gst_message_new_qos (GstObject * src, gboolean live, guint64 running_time,
@@ -1922,8 +1803,6 @@ gst_message_new_qos (GstObject * src, gboolean live, guint64 running_time,
  * Set the QoS values that have been calculated/analysed from the QoS data
  *
  * MT safe.
- *
- * Since: 0.10.29
  */
 void
 gst_message_set_qos_values (GstMessage * message, gint64 jitter,
@@ -1959,8 +1838,6 @@ gst_message_set_qos_values (GstMessage * message, gint64 jitter,
  * invalid. Values of -1 for either @processed or @dropped mean unknown values.
  *
  * MT safe.
- *
- * Since: 0.10.29
  */
 void
 gst_message_set_qos_stats (GstMessage * message, GstFormat format,
@@ -1998,8 +1875,6 @@ gst_message_set_qos_stats (GstMessage * message, GstFormat format,
  * values.
  *
  * MT safe.
- *
- * Since: 0.10.29
  */
 void
 gst_message_parse_qos (GstMessage * message, gboolean * live,
@@ -2034,8 +1909,6 @@ gst_message_parse_qos (GstMessage * message, gboolean * live,
  * Extract the QoS values that have been calculated/analysed from the QoS data
  *
  * MT safe.
- *
- * Since: 0.10.29
  */
 void
 gst_message_parse_qos_values (GstMessage * message, gint64 * jitter,
@@ -2072,8 +1945,6 @@ gst_message_parse_qos_values (GstMessage * message, gint64 * jitter,
  * invalid. Values of -1 for either @processed or @dropped mean unknown values.
  *
  * MT safe.
- *
- * Since: 0.10.29
  */
 void
 gst_message_parse_qos_stats (GstMessage * message, GstFormat * format,
@@ -2105,8 +1976,6 @@ gst_message_parse_qos_stats (GstMessage * message, GstFormat * format,
  * @test should contain a user visible string detailing the current action.
  *
  * Returns: (transfer full): The new qos message.
- *
- * Since: 0.10.33
  */
 GstMessage *
 gst_message_new_progress (GstObject * src, GstProgressType type,
@@ -2141,8 +2010,6 @@ gst_message_new_progress (GstObject * src, GstProgressType type,
  * @text: (out) (allow-none) (transfer full): location for the text
  *
  * Parses the progress @type, @code and @text.
- *
- * Since: 0.10.33
  */
 void
 gst_message_parse_progress (GstMessage * message, GstProgressType * type,
@@ -2159,3 +2026,408 @@ gst_message_parse_progress (GstMessage * message, GstProgressType * type,
       GST_QUARK (CODE), G_TYPE_STRING, code,
       GST_QUARK (TEXT), G_TYPE_STRING, text, NULL);
 }
+
+/**
+ * gst_message_new_toc:
+ * @src: the object originating the message.
+ * @toc: (transfer none): #GstToc structure for the message.
+ * @updated: whether TOC was updated or not.
+ *
+ * Create a new TOC message. The message is posted by elements
+ * that discovered or updated a TOC.
+ *
+ * Returns: (transfer full): a new TOC message.
+ *
+ * MT safe.
+ */
+GstMessage *
+gst_message_new_toc (GstObject * src, GstToc * toc, gboolean updated)
+{
+  GstStructure *toc_struct;
+
+  g_return_val_if_fail (toc != NULL, NULL);
+
+  toc_struct = gst_structure_new_id (GST_QUARK (MESSAGE_TOC),
+      GST_QUARK (TOC), GST_TYPE_TOC, toc,
+      GST_QUARK (UPDATED), G_TYPE_BOOLEAN, updated, NULL);
+
+  return gst_message_new_custom (GST_MESSAGE_TOC, src, toc_struct);
+}
+
+/**
+ * gst_message_parse_toc:
+ * @message: a valid #GstMessage of type GST_MESSAGE_TOC.
+ * @toc: (out) (transfer full): return location for the TOC.
+ * @updated: (out): return location for the updated flag.
+ *
+ * Extract the TOC from the #GstMessage. The TOC returned in the
+ * output argument is a copy; the caller must free it with
+ * gst_toc_unref() when done.
+ *
+ * MT safe.
+ */
+void
+gst_message_parse_toc (GstMessage * message, GstToc ** toc, gboolean * updated)
+{
+  g_return_if_fail (GST_IS_MESSAGE (message));
+  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_TOC);
+  g_return_if_fail (toc != NULL);
+
+  gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+      GST_QUARK (TOC), GST_TYPE_TOC, toc,
+      GST_QUARK (UPDATED), G_TYPE_BOOLEAN, updated, NULL);
+}
+
+/**
+ * gst_message_new_reset_time:
+ * @src: (transfer none): The object originating the message.
+ * @running_time: the requested running-time
+ *
+ * This message is posted when the pipeline running-time should be reset to
+ * @running_time, like after a flushing seek.
+ *
+ * Returns: (transfer full): The new reset_time message.
+ *
+ * MT safe.
+ */
+GstMessage *
+gst_message_new_reset_time (GstObject * src, GstClockTime running_time)
+{
+  GstMessage *message;
+  GstStructure *structure;
+
+  structure = gst_structure_new_id (GST_QUARK (MESSAGE_RESET_TIME),
+      GST_QUARK (RUNNING_TIME), G_TYPE_UINT64, running_time, NULL);
+  message = gst_message_new_custom (GST_MESSAGE_RESET_TIME, src, structure);
+
+  return message;
+}
+
+/**
+ * gst_message_parse_reset_time:
+ * @message: A valid #GstMessage of type GST_MESSAGE_RESET_TIME.
+ * @running_time: (out) (allow-none): Result location for the running_time or
+ *      %NULL
+ *
+ * Extract the running-time from the RESET_TIME message.
+ *
+ * MT safe.
+ */
+void
+gst_message_parse_reset_time (GstMessage * message, GstClockTime * running_time)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_IS_MESSAGE (message));
+  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_RESET_TIME);
+
+  structure = GST_MESSAGE_STRUCTURE (message);
+  if (running_time)
+    *running_time =
+        g_value_get_uint64 (gst_structure_id_get_value (structure,
+            GST_QUARK (RUNNING_TIME)));
+}
+
+/**
+ * gst_message_new_stream_start:
+ * @src: (transfer none): The object originating the message.
+ *
+ * Create a new stream_start message. This message is generated and posted in
+ * the sink elements of a GstBin. The bin will only forward the STREAM_START
+ * message to the application if all sinks have posted an STREAM_START message.
+ *
+ * Returns: (transfer full): The new stream_start message.
+ *
+ * MT safe.
+ */
+GstMessage *
+gst_message_new_stream_start (GstObject * src)
+{
+  GstMessage *message;
+  GstStructure *s;
+
+  s = gst_structure_new_id_empty (GST_QUARK (MESSAGE_STREAM_START));
+  message = gst_message_new_custom (GST_MESSAGE_STREAM_START, src, s);
+
+  return message;
+}
+
+
+/**
+ * gst_message_set_group_id:
+ * @message: the message
+ * @group_id: the group id
+ *
+ * Sets the group id on the stream-start message.
+ *
+ * All streams that have the same group id are supposed to be played
+ * together, i.e. all streams inside a container file should have the
+ * same group id but different stream ids. The group id should change
+ * each time the stream is started, resulting in different group ids
+ * each time a file is played for example.
+ *
+ * MT safe.
+ *
+ * Since: 1.2
+ */
+void
+gst_message_set_group_id (GstMessage * message, guint group_id)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_IS_MESSAGE (message));
+  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_STREAM_START);
+  g_return_if_fail (gst_message_is_writable (message));
+
+  structure = GST_MESSAGE_STRUCTURE (message);
+  gst_structure_id_set (structure, GST_QUARK (GROUP_ID), G_TYPE_UINT, group_id,
+      NULL);
+}
+
+/**
+ * gst_message_parse_group_id:
+ * @message: A valid #GstMessage of type GST_MESSAGE_STREAM_START.
+ * @group_id: (out) (allow-none): Result location for the group id or
+ *      %NULL
+ *
+ * Extract the group from the STREAM_START message.
+ *
+ * Returns: %TRUE if the message had a group id set, %FALSE otherwise
+ *
+ * MT safe.
+ *
+ * Since: 1.2
+ */
+gboolean
+gst_message_parse_group_id (GstMessage * message, guint * group_id)
+{
+  GstStructure *structure;
+  const GValue *v;
+
+  g_return_val_if_fail (GST_IS_MESSAGE (message), FALSE);
+  g_return_val_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_STREAM_START,
+      FALSE);
+
+  if (!group_id)
+    return TRUE;
+
+  structure = GST_MESSAGE_STRUCTURE (message);
+
+  v = gst_structure_id_get_value (structure, GST_QUARK (GROUP_ID));
+  if (!v)
+    return FALSE;
+
+  *group_id = g_value_get_uint (v);
+  return TRUE;
+}
+
+/**
+ * gst_message_new_need_context:
+ * @src: (transfer none): The object originating the message.
+ * @context_type: The context type that is needed
+ *
+ * This message is posted when an element needs a specific #GstContext.
+ *
+ * Returns: (transfer full): The new need-context message.
+ *
+ * MT safe.
+ *
+ * Since: 1.2
+ */
+GstMessage *
+gst_message_new_need_context (GstObject * src, const gchar * context_type)
+{
+  GstMessage *message;
+  GstStructure *structure;
+
+  g_return_val_if_fail (context_type != NULL, NULL);
+
+  structure = gst_structure_new_id (GST_QUARK (MESSAGE_NEED_CONTEXT),
+      GST_QUARK (CONTEXT_TYPE), G_TYPE_STRING, context_type, NULL);
+  message = gst_message_new_custom (GST_MESSAGE_NEED_CONTEXT, src, structure);
+
+  return message;
+}
+
+/**
+ * gst_message_parse_context_type:
+ * @message: a GST_MESSAGE_NEED_CONTEXT type message
+ * @context_type: (out) (allow-none): the context type, or %NULL
+ *
+ * Parse a context type from an existing GST_MESSAGE_NEED_CONTEXT message.
+ *
+ * Returns: a #gboolean indicating if the parsing succeeded.
+ *
+ * Since: 1.2
+ */
+gboolean
+gst_message_parse_context_type (GstMessage * message,
+    const gchar ** context_type)
+{
+  GstStructure *structure;
+  const GValue *value;
+
+  g_return_val_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_NEED_CONTEXT,
+      FALSE);
+
+  structure = GST_MESSAGE_STRUCTURE (message);
+
+  if (context_type) {
+    value = gst_structure_id_get_value (structure, GST_QUARK (CONTEXT_TYPE));
+    *context_type = g_value_get_string (value);
+  }
+
+  return TRUE;
+}
+
+/**
+ * gst_message_new_have_context:
+ * @src: (transfer none): The object originating the message.
+ * @context: (transfer full): the context
+ *
+ * This message is posted when an element has a new local #GstContext.
+ *
+ * Returns: (transfer full): The new have-context message.
+ *
+ * MT safe.
+ *
+ * Since: 1.2
+ */
+GstMessage *
+gst_message_new_have_context (GstObject * src, GstContext * context)
+{
+  GstMessage *message;
+  GstStructure *structure;
+
+  structure = gst_structure_new_id (GST_QUARK (MESSAGE_HAVE_CONTEXT),
+      GST_QUARK (CONTEXT), GST_TYPE_CONTEXT, context, NULL);
+  message = gst_message_new_custom (GST_MESSAGE_HAVE_CONTEXT, src, structure);
+  gst_context_unref (context);
+
+  return message;
+}
+
+/**
+ * gst_message_parse_have_context:
+ * @message: A valid #GstMessage of type GST_MESSAGE_HAVE_CONTEXT.
+ * @context: (out) (transfer full) (allow-none): Result location for the
+ *      context or %NULL
+ *
+ * Extract the context from the HAVE_CONTEXT message.
+ *
+ * MT safe.
+ *
+ * Since: 1.2
+ */
+void
+gst_message_parse_have_context (GstMessage * message, GstContext ** context)
+{
+  g_return_if_fail (GST_IS_MESSAGE (message));
+  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_HAVE_CONTEXT);
+
+  if (context)
+    gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+        GST_QUARK (CONTEXT), GST_TYPE_CONTEXT, context, NULL);
+}
+
+/**
+ * gst_message_new_device_added:
+ * @src: The #GstObject that created the message
+ * @device: (transfer none): The new #GstDevice
+ *
+ * Creates a new device-added message. The device-added message is produced by
+ * #GstDeviceMonitor or a #GstGlobalDeviceMonitor. They announce the appearance
+ * of monitored devices.
+ *
+ * Returns: a newly allocated #GstMessage
+ *
+ * Since: 1.4
+ */
+GstMessage *
+gst_message_new_device_added (GstObject * src, GstDevice * device)
+{
+  GstMessage *message;
+  GstStructure *structure;
+
+  g_return_val_if_fail (device != NULL, NULL);
+  g_return_val_if_fail (GST_IS_DEVICE (device), NULL);
+
+  structure = gst_structure_new_id (GST_QUARK (MESSAGE_DEVICE_ADDED),
+      GST_QUARK (DEVICE), GST_TYPE_DEVICE, device, NULL);
+  message = gst_message_new_custom (GST_MESSAGE_DEVICE_ADDED, src, structure);
+
+  return message;
+}
+
+/**
+ * gst_message_parse_device_added:
+ * @device: (out) (allow-none) (transfer none): A location where to store a
+ *  pointer to the new #GstDevice, or %NULL
+ * 
+ * Parses a device-added message. The device-added message is produced by
+ * #GstDeviceMonitor or a #GstGlobalDeviceMonitor. It announces the appearance
+ * of monitored devices.
+ *
+ * Since: 1.4
+ */
+void
+gst_message_parse_device_added (GstMessage * message, GstDevice ** device)
+{
+  g_return_if_fail (GST_IS_MESSAGE (message));
+  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DEVICE_ADDED);
+
+  if (device)
+    gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+        GST_QUARK (DEVICE), GST_TYPE_DEVICE, device, NULL);
+}
+
+/**
+ * gst_message_new_device_removed:
+ * @src: The #GstObject that created the message
+ * @device: (transfer none): The removed #GstDevice
+ *
+ * Creates a new device-removed message. The device-removed message is produced
+ * by #GstDeviceMonitor or a #GstGlobalDeviceMonitor. They announce the
+ * disappearance of monitored devices.
+ *
+ * Returns: a newly allocated #GstMessage
+ *
+ * Since: 1.4
+ */
+GstMessage *
+gst_message_new_device_removed (GstObject * src, GstDevice * device)
+{
+  GstMessage *message;
+  GstStructure *structure;
+
+  g_return_val_if_fail (device != NULL, NULL);
+  g_return_val_if_fail (GST_IS_DEVICE (device), NULL);
+
+  structure = gst_structure_new_id (GST_QUARK (MESSAGE_DEVICE_REMOVED),
+      GST_QUARK (DEVICE), GST_TYPE_DEVICE, device, NULL);
+  message = gst_message_new_custom (GST_MESSAGE_DEVICE_REMOVED, src, structure);
+
+  return message;
+}
+
+/**
+ * gst_message_parse_device_removed:
+ * @device: (out) (allow-none) (transfer none): A location where to store a
+ *  pointer to the removed #GstDevice, or %NULL
+ *
+ * Parses a device-removed message. The device-removed message is produced by
+ * #GstDeviceMonitor or a #GstGlobalDeviceMonitor. It announces the
+ * disappearance of monitored devices.
+ *
+ * Since: 1.4
+ */
+void
+gst_message_parse_device_removed (GstMessage * message, GstDevice ** device)
+{
+  g_return_if_fail (GST_IS_MESSAGE (message));
+  g_return_if_fail (GST_MESSAGE_TYPE (message) == GST_MESSAGE_DEVICE_REMOVED);
+
+  if (device)
+    gst_structure_id_get (GST_MESSAGE_STRUCTURE (message),
+        GST_QUARK (DEVICE), GST_TYPE_DEVICE, device, NULL);
+}