X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=gst%2Fgstquery.c;h=1a82747731b1e8135848fd228f814a608e4c79ae;hb=5688773b91c3ea1094996a573f119230727a0978;hp=a831d63a6f22c61d7bb28abb8cc895edaea81928;hpb=81736228445912859347832f61b407743b01c6b6;p=platform%2Fupstream%2Fgstreamer.git

diff --git a/gst/gstquery.c b/gst/gstquery.c
index a831d63..1a82747 100644
--- a/gst/gstquery.c
+++ b/gst/gstquery.c
@@ -17,12 +17,13 @@
  *
  * 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.
  */
 
 /**
  * SECTION:gstquery
+ * @title: GstQuery
  * @short_description: Provide functions to create queries, and to set and parse
  *                     values in them.
  * @see_also: #GstPad, #GstElement
@@ -36,27 +37,20 @@
  * gst_query_parse_*() helpers.
  *
  * The following example shows how to query the duration of a pipeline:
- *
- * <example>
- *  <title>Query duration on a pipeline</title>
- *  <programlisting>
- *  GstQuery *query;
- *  gboolean res;
- *  query = gst_query_new_duration (GST_FORMAT_TIME);
- *  res = gst_element_query (pipeline, query);
- *  if (res) {
- *    gint64 duration;
- *    gst_query_parse_duration (query, NULL, &amp;duration);
- *    g_print ("duration = %"GST_TIME_FORMAT, GST_TIME_ARGS (duration));
- *  }
- *  else {
- *    g_print ("duration query failed...");
- *  }
- *  gst_query_unref (query);
- *  </programlisting>
- * </example>
- *
- * Last reviewed on 2012-03-29 (0.11.3)
+ * |[<!-- language="C" -->
+ *   GstQuery *query;
+ *   gboolean res;
+ *   query = gst_query_new_duration (GST_FORMAT_TIME);
+ *   res = gst_element_query (pipeline, query);
+ *   if (res) {
+ *     gint64 duration;
+ *     gst_query_parse_duration (query, NULL, &amp;duration);
+ *     g_print ("duration = %"GST_TIME_FORMAT, GST_TIME_ARGS (duration));
+ *   } else {
+ *     g_print ("duration query failed...");
+ *   }
+ *   gst_query_unref (query);
+ * ]|
  */
 
 
@@ -72,7 +66,7 @@
 GST_DEBUG_CATEGORY_STATIC (gst_query_debug);
 #define GST_CAT_DEFAULT gst_query_debug
 
-static GType _gst_query_type = 0;
+GType _gst_query_type = 0;
 
 typedef struct
 {
@@ -110,6 +104,8 @@ static GstQueryQuarks query_quarks[] = {
   {GST_QUERY_ACCEPT_CAPS, "accept-caps", 0},
   {GST_QUERY_CAPS, "caps", 0},
   {GST_QUERY_DRAIN, "drain", 0},
+  {GST_QUERY_CONTEXT, "context", 0},
+  {GST_QUERY_BITRATE, "bitrate", 0},
 
   {0, NULL, 0}
 };
@@ -200,6 +196,9 @@ _gst_query_free (GstQuery * query)
     gst_structure_set_parent_refcount (s, NULL);
     gst_structure_free (s);
   }
+#ifdef USE_POISONING
+  memset (query, 0xff, sizeof (GstQueryImpl));
+#endif
 
   g_slice_free1 (sizeof (GstQueryImpl), query);
 }
@@ -227,7 +226,7 @@ _gst_query_copy (GstQuery * query)
  * when done with it. A position query is used to query the current position
  * of playback in the streams, in some format.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -274,11 +273,11 @@ gst_query_set_position (GstQuery * query, GstFormat format, gint64 cur)
  * gst_query_parse_position:
  * @query: a #GstQuery
  * @format: (out) (allow-none): the storage for the #GstFormat of the
- *     position values (may be NULL)
- * @cur: (out) (allow-none): the storage for the current position (may be NULL)
+ *     position values (may be %NULL)
+ * @cur: (out) (allow-none): the storage for the current position (may be %NULL)
  *
  * Parse a position query, writing the format into @format, and the position
- * into @cur, if the respective parameters are non-NULL.
+ * into @cur, if the respective parameters are non-%NULL.
  */
 void
 gst_query_parse_position (GstQuery * query, GstFormat * format, gint64 * cur)
@@ -306,7 +305,7 @@ gst_query_parse_position (GstQuery * query, GstFormat * format, gint64 * cur)
  * Use gst_query_unref() when done with it. A duration query will give the
  * total length of the stream.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -351,11 +350,11 @@ gst_query_set_duration (GstQuery * query, GstFormat format, gint64 duration)
  * gst_query_parse_duration:
  * @query: a #GstQuery
  * @format: (out) (allow-none): the storage for the #GstFormat of the duration
- *     value, or NULL.
- * @duration: (out) (allow-none): the storage for the total duration, or NULL.
+ *     value, or %NULL.
+ * @duration: (out) (allow-none): the storage for the total duration, or %NULL.
  *
  * Parse a duration query answer. Write the format of the duration into @format,
- * and the value into @duration, if the respective variables are non-NULL.
+ * and the value into @duration, if the respective variables are non-%NULL.
  */
 void
 gst_query_parse_duration (GstQuery * query, GstFormat * format,
@@ -383,11 +382,9 @@ gst_query_parse_duration (GstQuery * query, GstFormat * format,
  * by sinks to compensate for additional latency introduced by elements in the
  * pipeline.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a #GstQuery
- *
- * Since: 0.10.12
  */
 GstQuery *
 gst_query_new_latency (void)
@@ -398,7 +395,7 @@ gst_query_new_latency (void)
   structure = gst_structure_new_id (GST_QUARK (QUERY_LATENCY),
       GST_QUARK (LIVE), G_TYPE_BOOLEAN, FALSE,
       GST_QUARK (MIN_LATENCY), G_TYPE_UINT64, G_GUINT64_CONSTANT (0),
-      GST_QUARK (MAX_LATENCY), G_TYPE_UINT64, G_GUINT64_CONSTANT (-1), NULL);
+      GST_QUARK (MAX_LATENCY), G_TYPE_UINT64, GST_CLOCK_TIME_NONE, NULL);
 
   query = gst_query_new_custom (GST_QUERY_LATENCY, structure);
 
@@ -413,8 +410,6 @@ gst_query_new_latency (void)
  * @max_latency: the maximal latency of the upstream elements
  *
  * Answer a latency query by setting the requested values in the given format.
- *
- * Since: 0.10.12
  */
 void
 gst_query_set_latency (GstQuery * query, gboolean live,
@@ -423,6 +418,7 @@ gst_query_set_latency (GstQuery * query, gboolean live,
   GstStructure *structure;
 
   g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_LATENCY);
+  g_return_if_fail (GST_CLOCK_TIME_IS_VALID (min_latency));
 
   structure = GST_QUERY_STRUCTURE (query);
   gst_structure_id_set (structure,
@@ -434,13 +430,11 @@ gst_query_set_latency (GstQuery * query, gboolean live,
 /**
  * gst_query_parse_latency:
  * @query: a #GstQuery
- * @live: (out) (allow-none): storage for live or NULL
- * @min_latency: (out) (allow-none): the storage for the min latency or NULL
- * @max_latency: (out) (allow-none): the storage for the max latency or NULL
+ * @live: (out) (allow-none): storage for live or %NULL
+ * @min_latency: (out) (allow-none): the storage for the min latency or %NULL
+ * @max_latency: (out) (allow-none): the storage for the max latency or %NULL
  *
  * Parse a latency query answer.
- *
- * Since: 0.10.12
  */
 void
 gst_query_parse_latency (GstQuery * query, gboolean * live,
@@ -473,7 +467,7 @@ gst_query_parse_latency (GstQuery * query, gboolean * live,
  * when done with it. A convert query is used to ask for a conversion between
  * one format and another.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a #GstQuery
  */
@@ -525,15 +519,15 @@ gst_query_set_convert (GstQuery * query, GstFormat src_format, gint64 src_value,
  * gst_query_parse_convert:
  * @query: a #GstQuery
  * @src_format: (out) (allow-none): the storage for the #GstFormat of the
- *     source value, or NULL
- * @src_value: (out) (allow-none): the storage for the source value, or NULL
+ *     source value, or %NULL
+ * @src_value: (out) (allow-none): the storage for the source value, or %NULL
  * @dest_format: (out) (allow-none): the storage for the #GstFormat of the
- *     destination value, or NULL
+ *     destination value, or %NULL
  * @dest_value: (out) (allow-none): the storage for the destination value,
- *     or NULL
+ *     or %NULL
  *
  * Parse a convert query answer. Any of @src_format, @src_value, @dest_format,
- * and @dest_value may be NULL, in which case that value is omitted.
+ * and @dest_value may be %NULL, in which case that value is omitted.
  */
 void
 gst_query_parse_convert (GstQuery * query, GstFormat * src_format,
@@ -568,7 +562,7 @@ gst_query_parse_convert (GstQuery * query, GstFormat * src_format,
  * when done with it. A segment query is used to discover information about the
  * currently configured segment for playback.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -628,14 +622,14 @@ gst_query_set_segment (GstQuery * query, gdouble rate, GstFormat format,
 /**
  * gst_query_parse_segment:
  * @query: a #GstQuery
- * @rate: (out) (allow-none): the storage for the rate of the segment, or NULL
+ * @rate: (out) (allow-none): the storage for the rate of the segment, or %NULL
  * @format: (out) (allow-none): the storage for the #GstFormat of the values,
- *     or NULL
- * @start_value: (out) (allow-none): the storage for the start value, or NULL
- * @stop_value: (out) (allow-none): the storage for the stop value, or NULL
+ *     or %NULL
+ * @start_value: (out) (allow-none): the storage for the start value, or %NULL
+ * @stop_value: (out) (allow-none): the storage for the stop value, or %NULL
  *
  * Parse a segment query answer. Any of @rate, @format, @start_value, and
- * @stop_value may be NULL, which will cause this value to be omitted.
+ * @stop_value may be %NULL, which will cause this value to be omitted.
  *
  * See gst_query_set_segment() for an explanation of the function arguments.
  */
@@ -666,14 +660,14 @@ gst_query_parse_segment (GstQuery * query, gdouble * rate, GstFormat * format,
 /**
  * gst_query_new_custom:
  * @type: the query type
- * @structure: a structure for the query
+ * @structure: (allow-none) (transfer full): a structure for the query
  *
  * Constructs a new custom query object. Use gst_query_unref()
  * when done with it.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
- * Returns: (transfer full): a new #GstQuery
+ * Returns: (transfer full) (nullable): a new #GstQuery
  */
 GstQuery *
 gst_query_new_custom (GstQueryType type, GstStructure * structure)
@@ -715,9 +709,9 @@ had_parent:
  *
  * Get the structure of a query.
  *
- * Returns: (transfer none): the #GstStructure of the query. The structure is
- *     still owned by the query and will therefore be freed when the query
- *     is unreffed.
+ * Returns: (transfer none) (nullable): the #GstStructure of the query. The
+ *     structure is still owned by the query and will therefore be freed when the
+ *     query is unreffed.
  */
 const GstStructure *
 gst_query_get_structure (GstQuery * query)
@@ -732,7 +726,7 @@ gst_query_get_structure (GstQuery * query)
  * @query: a #GstQuery
  *
  * Get the structure of a query. This method should be called with a writable
- * @query so that the returned structure is guranteed to be writable.
+ * @query so that the returned structure is guaranteed to be writable.
  *
  * Returns: (transfer none): the #GstStructure of the query. The structure is
  *     still owned by the query and will therefore be freed when the query
@@ -741,10 +735,21 @@ gst_query_get_structure (GstQuery * query)
 GstStructure *
 gst_query_writable_structure (GstQuery * query)
 {
+  GstStructure *structure;
+
   g_return_val_if_fail (GST_IS_QUERY (query), NULL);
   g_return_val_if_fail (gst_query_is_writable (query), NULL);
 
-  return GST_QUERY_STRUCTURE (query);
+  structure = GST_QUERY_STRUCTURE (query);
+
+  if (structure == NULL) {
+    structure =
+        gst_structure_new_id_empty (gst_query_type_to_quark (GST_QUERY_TYPE
+            (query)));
+    gst_structure_set_parent_refcount (structure, &query->mini_object.refcount);
+    GST_QUERY_STRUCTURE (query) = structure;
+  }
+  return structure;
 }
 
 /**
@@ -754,7 +759,7 @@ gst_query_writable_structure (GstQuery * query)
  * Constructs a new query object for querying seeking properties of
  * the stream.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -806,14 +811,14 @@ gst_query_set_seeking (GstQuery * query, GstFormat format,
  * gst_query_parse_seeking:
  * @query: a GST_QUERY_SEEKING type query #GstQuery
  * @format: (out) (allow-none): the format to set for the @segment_start
- *     and @segment_end values, or NULL
- * @seekable: (out) (allow-none): the seekable flag to set, or NULL
- * @segment_start: (out) (allow-none): the segment_start to set, or NULL
- * @segment_end: (out) (allow-none): the segment_end to set, or NULL
+ *     and @segment_end values, or %NULL
+ * @seekable: (out) (allow-none): the seekable flag to set, or %NULL
+ * @segment_start: (out) (allow-none): the segment_start to set, or %NULL
+ * @segment_end: (out) (allow-none): the segment_end to set, or %NULL
  *
  * Parse a seeking query, writing the format into @format, and
  * other results into the passed parameters, if the respective parameters
- * are non-NULL
+ * are non-%NULL
  */
 void
 gst_query_parse_seeking (GstQuery * query, GstFormat * format,
@@ -870,11 +875,9 @@ ensure_array (GstStructure * s, GQuark quark, gsize element_size,
  * Constructs a new query object for querying formats of
  * the stream.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
- *
- * Since: 0.10.4
  */
 GstQuery *
 gst_query_new_formats (void)
@@ -943,8 +946,6 @@ gst_query_set_formats (GstQuery * query, gint n_formats, ...)
  *
  * Set the formats query result fields in @query. The number of formats passed
  * in the @formats array must be equal to @n_formats.
- *
- * Since: 0.10.4
  */
 void
 gst_query_set_formatsv (GstQuery * query, gint n_formats,
@@ -973,8 +974,6 @@ gst_query_set_formatsv (GstQuery * query, gint n_formats,
  * @n_formats: (out) (allow-none): the number of formats in this query.
  *
  * Parse the number of formats in the formats @query.
- *
- * Since: 0.10.4
  */
 void
 gst_query_parse_n_formats (GstQuery * query, guint * n_formats)
@@ -998,7 +997,7 @@ gst_query_parse_n_formats (GstQuery * query, guint * n_formats)
 /**
  * gst_query_parse_nth_format:
  * @query: a #GstQuery
- * @nth: (out): the nth format to retrieve.
+ * @nth: the nth format to retrieve.
  * @format: (out) (allow-none): a pointer to store the nth format
  *
  * Parse the format query and retrieve the @nth format from it into
@@ -1036,11 +1035,9 @@ gst_query_parse_nth_format (GstQuery * query, guint nth, GstFormat * format)
  * Constructs a new query object for querying the buffering status of
  * a stream.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
- *
- * Since: 0.10.20
  */
 GstQuery *
 gst_query_new_buffering (GstFormat format)
@@ -1075,8 +1072,6 @@ gst_query_new_buffering (GstFormat format)
  *
  * Set the percentage of buffered data. This is a value between 0 and 100.
  * The @busy indicator is %TRUE when the buffering is in progress.
- *
- * Since: 0.10.20
  */
 void
 gst_query_set_buffering_percent (GstQuery * query, gboolean busy, gint percent)
@@ -1096,13 +1091,11 @@ gst_query_set_buffering_percent (GstQuery * query, gboolean busy, gint percent)
 /**
  * gst_query_parse_buffering_percent:
  * @query: A valid #GstQuery of type GST_QUERY_BUFFERING.
- * @busy: (out) (allow-none): if buffering is busy, or NULL
- * @percent: (out) (allow-none): a buffering percent, or NULL
+ * @busy: (out) (allow-none): if buffering is busy, or %NULL
+ * @percent: (out) (allow-none): a buffering percent, or %NULL
  *
  * Get the percentage of buffered data. This is a value between 0 and 100.
  * The @busy indicator is %TRUE when the buffering is in progress.
- *
- * Since: 0.10.20
  */
 void
 gst_query_parse_buffering_percent (GstQuery * query, gboolean * busy,
@@ -1127,11 +1120,9 @@ gst_query_parse_buffering_percent (GstQuery * query, gboolean * busy,
  * @mode: a buffering mode
  * @avg_in: the average input rate
  * @avg_out: the average output rate
- * @buffering_left: amount of buffering time left
+ * @buffering_left: amount of buffering time left in milliseconds
  *
  * Configures the buffering stats values in @query.
- *
- * Since: 0.10.20
  */
 void
 gst_query_set_buffering_stats (GstQuery * query, GstBufferingMode mode,
@@ -1153,14 +1144,13 @@ gst_query_set_buffering_stats (GstQuery * query, GstBufferingMode mode,
 /**
  * gst_query_parse_buffering_stats:
  * @query: A valid #GstQuery of type GST_QUERY_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 rat, or NULLe
- * @buffering_left: (out) (allow-none): amount of buffering time left, 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 rat, or %NULL
+ * @buffering_left: (out) (allow-none): amount of buffering time left in
+ *     milliseconds, or %NULL
  *
  * Extracts the buffering stats values from @query.
- *
- * Since: 0.10.20
  */
 void
 gst_query_parse_buffering_stats (GstQuery * query,
@@ -1194,11 +1184,10 @@ gst_query_parse_buffering_stats (GstQuery * query,
  * @format: the format to set for the @start and @stop values
  * @start: the start to set
  * @stop: the stop to set
- * @estimated_total: estimated total amount of download time
+ * @estimated_total: estimated total amount of download time remaining in
+ *     milliseconds
  *
  * Set the available query result fields in @query.
- *
- * Since: 0.10.20
  */
 void
 gst_query_set_buffering_range (GstQuery * query, GstFormat format,
@@ -1221,17 +1210,15 @@ gst_query_set_buffering_range (GstQuery * query, GstFormat format,
  * gst_query_parse_buffering_range:
  * @query: a GST_QUERY_BUFFERING type query #GstQuery
  * @format: (out) (allow-none): the format to set for the @segment_start
- *     and @segment_end values, or NULL
- * @start: (out) (allow-none): the start to set, or NULL
- * @stop: (out) (allow-none): the stop to set, or NULL
+ *     and @segment_end values, or %NULL
+ * @start: (out) (allow-none): the start to set, or %NULL
+ * @stop: (out) (allow-none): the stop to set, or %NULL
  * @estimated_total: (out) (allow-none): estimated total amount of download
- *     time, or NULL
+ *     time remaining in milliseconds, or %NULL
  *
  * Parse an available query, writing the format into @format, and
  * other results into the passed parameters, if the respective parameters
- * are non-NULL
- *
- * Since: 0.10.20
+ * are non-%NULL
  */
 void
 gst_query_parse_buffering_range (GstQuery * query, GstFormat * format,
@@ -1275,8 +1262,6 @@ typedef struct
  * start position of the array should be inferior to @start.
  *
  * Returns: a #gboolean indicating if the range was added or not.
- *
- * Since: 0.10.31
  */
 gboolean
 gst_query_add_buffering_range (GstQuery * query, gint64 start, gint64 stop)
@@ -1319,8 +1304,6 @@ gst_query_add_buffering_range (GstQuery * query, gint64 start, gint64 stop)
  * buffered-ranges array of the query's structure.
  *
  * Returns: the range array size as a #guint.
- *
- * Since: 0.10.31
  */
 guint
 gst_query_get_n_buffering_ranges (GstQuery * query)
@@ -1342,15 +1325,13 @@ gst_query_get_n_buffering_ranges (GstQuery * query)
  * gst_query_parse_nth_buffering_range:
  * @query: a GST_QUERY_BUFFERING type query #GstQuery
  * @index: position in the buffered-ranges array to read
- * @start: (out) (allow-none): the start position to set, or NULL
- * @stop: (out) (allow-none): the stop position to set, or NULL
+ * @start: (out) (allow-none): the start position to set, or %NULL
+ * @stop: (out) (allow-none): the stop position to set, or %NULL
  *
  * Parse an available query and get the start and stop values stored
  * at the @index of the buffered ranges array.
  *
  * Returns: a #gboolean indicating if the parsing succeeded.
- *
- * Since: 0.10.31
  */
 gboolean
 gst_query_parse_nth_buffering_range (GstQuery * query, guint index,
@@ -1386,11 +1367,9 @@ gst_query_parse_nth_buffering_range (GstQuery * query, guint index,
  * when done with it. An URI query is used to query the current URI
  * that is used by the source or sink.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
- *
- * Since: 0.10.22
  */
 GstQuery *
 gst_query_new_uri (void)
@@ -1412,8 +1391,6 @@ gst_query_new_uri (void)
  * @uri: the URI to set
  *
  * Answer a URI query by setting the requested URI.
- *
- * Since: 0.10.22
  */
 void
 gst_query_set_uri (GstQuery * query, const gchar * uri)
@@ -1431,14 +1408,12 @@ gst_query_set_uri (GstQuery * query, const gchar * uri)
 /**
  * gst_query_parse_uri:
  * @query: a #GstQuery
- * @uri: (out callee-allocates) (allow-none): the storage for the current URI
- *     (may be NULL)
+ * @uri: (out) (transfer full) (allow-none): the storage for the current URI
+ *     (may be %NULL)
  *
  * Parse an URI query, writing the URI into @uri as a newly
- * allocated string, if the respective parameters are non-NULL.
+ * allocated string, if the respective parameters are non-%NULL.
  * Free the string with g_free() after usage.
- *
- * Since: 0.10.22
  */
 void
 gst_query_parse_uri (GstQuery * query, gchar ** uri)
@@ -1454,13 +1429,115 @@ gst_query_parse_uri (GstQuery * query, gchar ** uri)
 }
 
 /**
+ * gst_query_set_uri_redirection:
+ * @query: a #GstQuery with query type GST_QUERY_URI
+ * @uri: the URI to set
+ *
+ * Answer a URI query by setting the requested URI redirection.
+ *
+ * Since: 1.2
+ */
+void
+gst_query_set_uri_redirection (GstQuery * query, const gchar * uri)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
+  g_return_if_fail (gst_query_is_writable (query));
+  g_return_if_fail (gst_uri_is_valid (uri));
+
+  structure = GST_QUERY_STRUCTURE (query);
+  gst_structure_id_set (structure, GST_QUARK (URI_REDIRECTION),
+      G_TYPE_STRING, uri, NULL);
+}
+
+/**
+ * gst_query_parse_uri_redirection:
+ * @query: a #GstQuery
+ * @uri: (out) (transfer full) (allow-none): the storage for the redirect URI
+ *     (may be %NULL)
+ *
+ * Parse an URI query, writing the URI into @uri as a newly
+ * allocated string, if the respective parameters are non-%NULL.
+ * Free the string with g_free() after usage.
+ *
+ * Since: 1.2
+ */
+void
+gst_query_parse_uri_redirection (GstQuery * query, gchar ** uri)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
+
+  structure = GST_QUERY_STRUCTURE (query);
+  if (uri) {
+    if (!gst_structure_id_get (structure, GST_QUARK (URI_REDIRECTION),
+            G_TYPE_STRING, uri, NULL))
+      *uri = NULL;
+  }
+}
+
+/**
+ * gst_query_set_uri_redirection_permanent:
+ * @query: a #GstQuery with query type %GST_QUERY_URI
+ * @permanent: whether the redirect is permanent or not
+ *
+ * Answer a URI query by setting the requested URI redirection
+ * to permanent or not.
+ *
+ * Since: 1.4
+ */
+void
+gst_query_set_uri_redirection_permanent (GstQuery * query, gboolean permanent)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
+  g_return_if_fail (gst_query_is_writable (query));
+
+  structure = GST_QUERY_STRUCTURE (query);
+  gst_structure_id_set (structure, GST_QUARK (URI_REDIRECTION_PERMANENT),
+      G_TYPE_BOOLEAN, permanent, NULL);
+}
+
+/**
+ * gst_query_parse_uri_redirection_permanent:
+ * @query: a #GstQuery
+ * @permanent: (out) (allow-none): if the URI redirection is permanent
+ *     (may be %NULL)
+ *
+ * Parse an URI query, and set @permanent to %TRUE if there is a redirection
+ * and it should be considered permanent. If a redirection is permanent,
+ * applications should update their internal storage of the URI, otherwise
+ * they should make all future requests to the original URI.
+ *
+ * Since: 1.4
+ */
+void
+gst_query_parse_uri_redirection_permanent (GstQuery * query,
+    gboolean * permanent)
+{
+  GstStructure *structure;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_URI);
+
+  structure = GST_QUERY_STRUCTURE (query);
+  if (permanent) {
+    if (!gst_structure_id_get (structure, GST_QUARK (URI_REDIRECTION_PERMANENT),
+            G_TYPE_BOOLEAN, permanent, NULL))
+      *permanent = FALSE;
+  }
+}
+
+/**
  * gst_query_new_allocation:
  * @caps: the negotiated caps
  * @need_pool: return a pool
  *
  * Constructs a new query object for querying the allocation properties.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -1487,7 +1564,10 @@ gst_query_new_allocation (GstCaps * caps, gboolean need_pool)
  *
  * Parse an allocation query, writing the requested caps in @caps and
  * whether a pool is needed in @need_pool, if the respective parameters
- * are non-NULL.
+ * are non-%NULL.
+ *
+ * Pool details can be retrieved using gst_query_get_n_allocation_pools() and
+ * gst_query_parse_nth_allocation_pool().
  */
 void
 gst_query_parse_allocation (GstQuery * query, GstCaps ** caps,
@@ -1524,8 +1604,8 @@ allocation_pool_free (AllocationPool * ap)
 /**
  * gst_query_add_allocation_pool:
  * @query: A valid #GstQuery of type GST_QUERY_ALLOCATION.
- * @pool: the #GstBufferPool
- * @size: the size
+ * @pool: (transfer none) (allow-none): the #GstBufferPool
+ * @size: the buffer size
  * @min_buffers: the min buffers
  * @max_buffers: the max buffers
  *
@@ -1541,7 +1621,6 @@ gst_query_add_allocation_pool (GstQuery * query, GstBufferPool * pool,
 
   g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
   g_return_if_fail (gst_query_is_writable (query));
-  g_return_if_fail (size != 0);
 
   structure = GST_QUERY_STRUCTURE (query);
   array = ensure_array (structure, GST_QUARK (POOL),
@@ -1556,7 +1635,6 @@ gst_query_add_allocation_pool (GstQuery * query, GstBufferPool * pool,
   g_array_append_val (array, ap);
 }
 
-
 /**
  * gst_query_get_n_allocation_pools:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
@@ -1585,12 +1663,14 @@ gst_query_get_n_allocation_pools (GstQuery * query)
  * gst_query_parse_nth_allocation_pool:
  * @query: A valid #GstQuery of type GST_QUERY_ALLOCATION.
  * @index: index to parse
- * @pool: (out) (allow-none) (transfer none): the #GstBufferPool
- * @size: (out) (allow-none): the size
+ * @pool: (out) (allow-none) (transfer full): the #GstBufferPool
+ * @size: (out) (allow-none): the buffer size
  * @min_buffers: (out) (allow-none): the min buffers
  * @max_buffers: (out) (allow-none): the max buffers
  *
  * Get the pool parameters in @query.
+ *
+ * Unref @pool with gst_object_unref() when it's not needed any more.
  */
 void
 gst_query_parse_nth_allocation_pool (GstQuery * query, guint index,
@@ -1625,8 +1705,8 @@ gst_query_parse_nth_allocation_pool (GstQuery * query, guint index,
  * gst_query_set_nth_allocation_pool:
  * @index: index to modify
  * @query: A valid #GstQuery of type GST_QUERY_ALLOCATION.
- * @pool: the #GstBufferPool
- * @size: the size
+ * @pool: (transfer none) (allow-none): the #GstBufferPool
+ * @size: the buffer size
  * @min_buffers: the min buffers
  * @max_buffers: the max buffers
  *
@@ -1658,22 +1738,57 @@ gst_query_set_nth_allocation_pool (GstQuery * query, guint index,
   g_array_index (array, AllocationPool, index) = ap;
 }
 
+/**
+ * gst_query_remove_nth_allocation_pool:
+ * @query: a GST_QUERY_ALLOCATION type query #GstQuery
+ * @index: position in the allocation pool array to remove
+ *
+ * Remove the allocation pool at @index of the allocation pool array.
+ *
+ * Since: 1.2
+ */
+void
+gst_query_remove_nth_allocation_pool (GstQuery * query, guint index)
+{
+  GArray *array;
+  GstStructure *structure;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
+  g_return_if_fail (gst_query_is_writable (query));
+
+  structure = GST_QUERY_STRUCTURE (query);
+  array =
+      ensure_array (structure, GST_QUARK (POOL), sizeof (AllocationPool),
+      (GDestroyNotify) allocation_pool_free);
+  g_return_if_fail (index < array->len);
+
+  g_array_remove_index (array, index);
+}
+
 typedef struct
 {
   GType api;
-  guint flags;
+  GstStructure *params;
 } AllocationMeta;
 
+static void
+allocation_meta_free (AllocationMeta * am)
+{
+  if (am->params)
+    gst_structure_free (am->params);
+}
+
 /**
  * gst_query_add_allocation_meta:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
  * @api: the metadata API
- * @flags: API specific flags
+ * @params: (transfer none) (allow-none): API specific parameters
  *
- * Add @api with @flags as one of the supported metadata API to @query.
+ * Add @api with @params as one of the supported metadata API to @query.
  */
 void
-gst_query_add_allocation_meta (GstQuery * query, GType api, guint flags)
+gst_query_add_allocation_meta (GstQuery * query, GType api,
+    const GstStructure * params)
 {
   GArray *array;
   GstStructure *structure;
@@ -1685,10 +1800,11 @@ gst_query_add_allocation_meta (GstQuery * query, GType api, guint flags)
 
   structure = GST_QUERY_STRUCTURE (query);
   array =
-      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta), NULL);
+      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
+      (GDestroyNotify) allocation_meta_free);
 
   am.api = api;
-  am.flags = flags;
+  am.params = (params ? gst_structure_copy (params) : NULL);
 
   g_array_append_val (array, am);
 }
@@ -1712,7 +1828,8 @@ gst_query_get_n_allocation_metas (GstQuery * query)
 
   structure = GST_QUERY_STRUCTURE (query);
   array =
-      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta), NULL);
+      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
+      (GDestroyNotify) allocation_meta_free);
 
   return array->len;
 }
@@ -1721,7 +1838,7 @@ gst_query_get_n_allocation_metas (GstQuery * query)
  * gst_query_parse_nth_allocation_meta:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
  * @index: position in the metadata API array to read
- * @flags: (out) (allow-none): API specific flags
+ * @params: (out) (transfer none) (allow-none): API specific parameters
  *
  * Parse an available query and get the metadata API
  * at @index of the metadata API array.
@@ -1730,7 +1847,7 @@ gst_query_get_n_allocation_metas (GstQuery * query)
  */
 GType
 gst_query_parse_nth_allocation_meta (GstQuery * query, guint index,
-    guint * flags)
+    const GstStructure ** params)
 {
   GArray *array;
   GstStructure *structure;
@@ -1740,14 +1857,15 @@ gst_query_parse_nth_allocation_meta (GstQuery * query, guint index,
 
   structure = GST_QUERY_STRUCTURE (query);
   array =
-      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta), NULL);
+      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
+      (GDestroyNotify) allocation_meta_free);
 
   g_return_val_if_fail (index < array->len, 0);
 
   am = &g_array_index (array, AllocationMeta, index);
 
-  if (flags)
-    *flags = am->flags;
+  if (params)
+    *params = am->params;
 
   return am->api;
 }
@@ -1770,23 +1888,27 @@ gst_query_remove_nth_allocation_meta (GstQuery * query, guint index)
 
   structure = GST_QUERY_STRUCTURE (query);
   array =
-      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta), NULL);
+      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
+      (GDestroyNotify) allocation_meta_free);
   g_return_if_fail (index < array->len);
 
   g_array_remove_index (array, index);
 }
 
 /**
- * gst_query_has_allocation_meta:
+ * gst_query_find_allocation_meta:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
  * @api: the metadata API
+ * @index: (out) (transfer none) (allow-none): the index
  *
- * Check if @query has metadata @api set.
+ * Check if @query has metadata @api set. When this function returns %TRUE,
+ * @index will contain the index where the requested API and the parameters
+ * can be found.
  *
- * Returns: TRUE when @api is in the list of metadata.
+ * Returns: %TRUE when @api is in the list of metadata.
  */
 gboolean
-gst_query_has_allocation_meta (GstQuery * query, GType api)
+gst_query_find_allocation_meta (GstQuery * query, GType api, guint * index)
 {
   GArray *array;
   GstStructure *structure;
@@ -1797,13 +1919,17 @@ gst_query_has_allocation_meta (GstQuery * query, GType api)
 
   structure = GST_QUERY_STRUCTURE (query);
   array =
-      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta), NULL);
+      ensure_array (structure, GST_QUARK (META), sizeof (AllocationMeta),
+      (GDestroyNotify) allocation_meta_free);
 
   len = array->len;
   for (i = 0; i < len; i++) {
     AllocationMeta *am = &g_array_index (array, AllocationMeta, i);
-    if (am->api == api)
+    if (am->api == api) {
+      if (index)
+        *index = i;
       return TRUE;
+    }
   }
   return FALSE;
 }
@@ -1818,14 +1944,14 @@ static void
 allocation_param_free (AllocationParam * ap)
 {
   if (ap->allocator)
-    gst_allocator_unref (ap->allocator);
+    gst_object_unref (ap->allocator);
 }
 
 /**
  * gst_query_add_allocation_param:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
- * @allocator: the memory allocator
- * @params: a #GstAllocationParams
+ * @allocator: (transfer none) (allow-none): the memory allocator
+ * @params: (transfer none) (allow-none): a #GstAllocationParams
  *
  * Add @allocator and its @params as a supported memory allocator.
  */
@@ -1846,7 +1972,7 @@ gst_query_add_allocation_param (GstQuery * query, GstAllocator * allocator,
       sizeof (AllocationParam), (GDestroyNotify) allocation_param_free);
 
   if ((ap.allocator = allocator))
-    gst_allocator_ref (allocator);
+    gst_object_ref (allocator);
   if (params)
     ap.params = *params;
   else
@@ -1863,7 +1989,9 @@ gst_query_add_allocation_param (GstQuery * query, GstAllocator * allocator,
  * allocator params array of the query's structure.
  *
  * If no memory allocator is specified, the downstream element can handle
- * the default memory allocator.
+ * the default memory allocator. The first memory allocator in the query
+ * should be generic and allow mapping to system memory, all following
+ * allocators should be ordered by preference with the preferred one first.
  *
  * Returns: the allocator array size as a #guint.
  */
@@ -1886,10 +2014,10 @@ gst_query_get_n_allocation_params (GstQuery * query)
  * gst_query_parse_nth_allocation_param:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
  * @index: position in the allocator array to read
- * @allocator: (transfer none): variable to hold the result
- * @params: parameters for the allocator
+ * @allocator: (out) (transfer full) (allow-none): variable to hold the result
+ * @params: (out) (allow-none): parameters for the allocator
  *
- * Parse an available query and get the alloctor and its params
+ * Parse an available query and get the allocator and its params
  * at @index of the allocator array.
  */
 void
@@ -1911,7 +2039,7 @@ gst_query_parse_nth_allocation_param (GstQuery * query, guint index,
 
   if (allocator)
     if ((*allocator = ap->allocator))
-      gst_allocator_ref (*allocator);
+      gst_object_ref (*allocator);
   if (params)
     *params = ap->params;
 }
@@ -1920,10 +2048,10 @@ gst_query_parse_nth_allocation_param (GstQuery * query, guint index,
  * gst_query_set_nth_allocation_param:
  * @query: a GST_QUERY_ALLOCATION type query #GstQuery
  * @index: position in the allocator array to set
- * @allocator: (transfer full): new allocator to set
- * @params: parameters for the allocator
+ * @allocator: (transfer none) (allow-none): new allocator to set
+ * @params: (transfer none) (allow-none): parameters for the allocator
  *
- * Parse an available query and get the alloctor and its params
+ * Parse an available query and get the allocator and its params
  * at @index of the allocator array.
  */
 void
@@ -1945,7 +2073,7 @@ gst_query_set_nth_allocation_param (GstQuery * query, guint index,
   allocation_param_free (old);
 
   if ((ap.allocator = allocator))
-    gst_allocator_ref (allocator);
+    gst_object_ref (allocator);
   if (params)
     ap.params = *params;
   else
@@ -1955,11 +2083,38 @@ gst_query_set_nth_allocation_param (GstQuery * query, guint index,
 }
 
 /**
+ * gst_query_remove_nth_allocation_param:
+ * @query: a GST_QUERY_ALLOCATION type query #GstQuery
+ * @index: position in the allocation param array to remove
+ *
+ * Remove the allocation param at @index of the allocation param array.
+ *
+ * Since: 1.2
+ */
+void
+gst_query_remove_nth_allocation_param (GstQuery * query, guint index)
+{
+  GArray *array;
+  GstStructure *structure;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_ALLOCATION);
+  g_return_if_fail (gst_query_is_writable (query));
+
+  structure = GST_QUERY_STRUCTURE (query);
+  array =
+      ensure_array (structure, GST_QUARK (ALLOCATOR), sizeof (AllocationParam),
+      (GDestroyNotify) allocation_param_free);
+  g_return_if_fail (index < array->len);
+
+  g_array_remove_index (array, index);
+}
+
+/**
  * gst_query_new_scheduling:
  *
  * Constructs a new query object for querying the scheduling properties.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -2037,7 +2192,7 @@ gst_query_parse_scheduling (GstQuery * query, GstSchedulingFlags * flags,
  * @query: a GST_QUERY_SCHEDULING type query #GstQuery
  * @mode: a #GstPadMode
  *
- * Add @mode as aone of the supported scheduling modes to @query.
+ * Add @mode as one of the supported scheduling modes to @query.
  */
 void
 gst_query_add_scheduling_mode (GstQuery * query, GstPadMode mode)
@@ -2113,7 +2268,13 @@ gst_query_parse_nth_scheduling_mode (GstQuery * query, guint index)
  *
  * Check if @query has scheduling mode set.
  *
- * Returns: TRUE when @mode is in the list of scheduling modes.
+ * > When checking if upstream supports pull mode, it is usually not
+ * > enough to just check for GST_PAD_MODE_PULL with this function, you
+ * > also want to check whether the scheduling flags returned by
+ * > gst_query_parse_scheduling() have the seeking flag set (meaning
+ * > random access is supported, not only sequential pulls).
+ *
+ * Returns: %TRUE when @mode is in the list of scheduling modes.
  */
 gboolean
 gst_query_has_scheduling_mode (GstQuery * query, GstPadMode mode)
@@ -2137,12 +2298,38 @@ gst_query_has_scheduling_mode (GstQuery * query, GstPadMode mode)
 }
 
 /**
+ * gst_query_has_scheduling_mode_with_flags:
+ * @query: a GST_QUERY_SCHEDULING type query #GstQuery
+ * @mode: the scheduling mode
+ * @flags: #GstSchedulingFlags
+ *
+ * Check if @query has scheduling mode set and @flags is set in
+ * query scheduling flags.
+ *
+ * Returns: %TRUE when @mode is in the list of scheduling modes
+ *    and @flags are compatible with query flags.
+ */
+gboolean
+gst_query_has_scheduling_mode_with_flags (GstQuery * query, GstPadMode mode,
+    GstSchedulingFlags flags)
+{
+  GstSchedulingFlags sched_flags;
+
+  g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_SCHEDULING, FALSE);
+
+  gst_query_parse_scheduling (query, &sched_flags, NULL, NULL, NULL);
+
+  return ((flags & sched_flags) == flags) &&
+      gst_query_has_scheduling_mode (query, mode);
+}
+
+/**
  * gst_query_new_accept_caps:
  * @caps: a fixed #GstCaps
  *
  * Constructs a new query object for querying if @caps are accepted.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -2165,7 +2352,7 @@ gst_query_new_accept_caps (GstCaps * caps)
 /**
  * gst_query_parse_accept_caps:
  * @query: The query to parse
- * @caps: (out): A pointer to the caps
+ * @caps: (out) (transfer none): A pointer to the caps
  *
  * Get the caps from @query. The caps remains valid as long as @query remains
  * valid.
@@ -2206,7 +2393,7 @@ gst_query_set_accept_caps_result (GstQuery * query, gboolean result)
 /**
  * gst_query_parse_accept_caps_result:
  * @query: a GST_QUERY_ACCEPT_CAPS type query #GstQuery
- * @result: location for the result
+ * @result: (out) (allow-none): location for the result
  *
  * Parse the result from @query and store in @result.
  */
@@ -2245,7 +2432,7 @@ gst_query_parse_accept_caps_result (GstQuery * query, gboolean * result)
  * @filter should be returned from the CAPS query. Specifying a filter might
  * greatly reduce the amount of processing an element needs to do.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -2266,7 +2453,7 @@ gst_query_new_caps (GstCaps * filter)
 /**
  * gst_query_parse_caps:
  * @query: The query to parse
- * @filter: (out): A pointer to the caps filter
+ * @filter: (out) (transfer none): A pointer to the caps filter
  *
  * Get the filter from the caps @query. The caps remains valid as long as
  * @query remains valid.
@@ -2306,7 +2493,7 @@ gst_query_set_caps_result (GstQuery * query, GstCaps * caps)
 /**
  * gst_query_parse_caps_result:
  * @query: The query to parse
- * @caps: (out): A pointer to the caps
+ * @caps: (out) (transfer none): A pointer to the caps
  *
  * Get the caps result from @query. The caps remains valid as long as
  * @query remains valid.
@@ -2343,7 +2530,7 @@ gst_query_intersect_caps_result (GstQuery * query, GstCaps * filter,
  *
  * Constructs a new query object for querying the drain state.
  *
- * Free-function: gst_query_unref
+ * Free-function: gst_query_unref()
  *
  * Returns: (transfer full): a new #GstQuery
  */
@@ -2358,3 +2545,185 @@ gst_query_new_drain (void)
 
   return query;
 }
+
+/**
+ * gst_query_new_context:
+ * @context_type: Context type to query
+ *
+ * Constructs a new query object for querying the pipeline-local context.
+ *
+ * Free-function: gst_query_unref()
+ *
+ * Returns: (transfer full): a new #GstQuery
+ *
+ * Since: 1.2
+ */
+GstQuery *
+gst_query_new_context (const gchar * context_type)
+{
+  GstQuery *query;
+  GstStructure *structure;
+
+  g_return_val_if_fail (context_type != NULL, NULL);
+
+  structure = gst_structure_new_id (GST_QUARK (QUERY_CONTEXT),
+      GST_QUARK (CONTEXT_TYPE), G_TYPE_STRING, context_type, NULL);
+  query = gst_query_new_custom (GST_QUERY_CONTEXT, structure);
+
+  return query;
+}
+
+/**
+ * gst_query_set_context:
+ * @query: a #GstQuery with query type GST_QUERY_CONTEXT
+ * @context: the requested #GstContext
+ *
+ * Answer a context query by setting the requested context.
+ *
+ * Since: 1.2
+ */
+void
+gst_query_set_context (GstQuery * query, GstContext * context)
+{
+  GstStructure *s;
+  const gchar *context_type;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT);
+
+  gst_query_parse_context_type (query, &context_type);
+  g_return_if_fail (strcmp (gst_context_get_context_type (context),
+          context_type) == 0);
+
+  s = GST_QUERY_STRUCTURE (query);
+
+  gst_structure_id_set (s,
+      GST_QUARK (CONTEXT), GST_TYPE_CONTEXT, context, NULL);
+}
+
+/**
+ * gst_query_parse_context:
+ * @query: The query to parse
+ * @context: (out) (transfer none): A pointer to store the #GstContext
+ *
+ * Get the context from the context @query. The context remains valid as long as
+ * @query remains valid.
+ *
+ * Since: 1.2
+ */
+void
+gst_query_parse_context (GstQuery * query, GstContext ** context)
+{
+  GstStructure *structure;
+  const GValue *v;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT);
+  g_return_if_fail (context != NULL);
+
+  structure = GST_QUERY_STRUCTURE (query);
+  v = gst_structure_id_get_value (structure, GST_QUARK (CONTEXT));
+  if (v)
+    *context = g_value_get_boxed (v);
+  else
+    *context = NULL;
+}
+
+/**
+ * gst_query_parse_context_type:
+ * @query: a GST_QUERY_CONTEXT type query
+ * @context_type: (out) (transfer none) (allow-none): the context type, or %NULL
+ *
+ * Parse a context type from an existing GST_QUERY_CONTEXT query.
+ *
+ * Returns: a #gboolean indicating if the parsing succeeded.
+ *
+ * Since: 1.2
+ */
+gboolean
+gst_query_parse_context_type (GstQuery * query, const gchar ** context_type)
+{
+  GstStructure *structure;
+  const GValue *value;
+
+  g_return_val_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_CONTEXT, FALSE);
+
+  structure = GST_QUERY_STRUCTURE (query);
+
+  if (context_type) {
+    value = gst_structure_id_get_value (structure, GST_QUARK (CONTEXT_TYPE));
+    *context_type = g_value_get_string (value);
+  }
+
+  return TRUE;
+}
+
+/**
+ * gst_query_new_bitrate:
+ *
+ * Constructs a new query object for querying the bitrate.
+ *
+ * Free-function: gst_query_unref()
+ *
+ * Returns: (transfer full): a new #GstQuery
+ *
+ * Since: 1.16
+ */
+GstQuery *
+gst_query_new_bitrate (void)
+{
+  GstQuery *query;
+  GstStructure *structure;
+
+  structure = gst_structure_new_id_empty (GST_QUARK (QUERY_BITRATE));
+  query = gst_query_new_custom (GST_QUERY_BITRATE, structure);
+
+  return query;
+}
+
+/**
+ * gst_query_set_bitrate:
+ * @query: a GST_QUERY_BITRATE type #GstQuery
+ * @nominal_bitrate: the nominal bitrate in bits per second
+ *
+ * Set the results of a bitrate query.  The nominal bitrate is the average
+ * bitrate expected over the length of the stream as advertised in file
+ * headers (or similar).
+ *
+ * Since: 1.16
+ */
+void
+gst_query_set_bitrate (GstQuery * query, guint nominal_bitrate)
+{
+  GstStructure *s;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BITRATE);
+
+  s = GST_QUERY_STRUCTURE (query);
+
+  gst_structure_id_set (s,
+      GST_QUARK (NOMINAL_BITRATE), G_TYPE_UINT, nominal_bitrate, NULL);
+}
+
+/**
+ * gst_query_parse_bitrate:
+ * @query: a GST_QUERY_BITRATE type #GstQuery
+ * @nominal_bitrate: (out) (allow-none): The resulting bitrate in bits per second
+ *
+ * Get the results of a bitrate query. See also gst_query_set_bitrate().
+ *
+ * Since: 1.16
+ */
+void
+gst_query_parse_bitrate (GstQuery * query, guint * nominal_bitrate)
+{
+  GstStructure *structure;
+  const GValue *value;
+
+  g_return_if_fail (GST_QUERY_TYPE (query) == GST_QUERY_BITRATE);
+
+  structure = GST_QUERY_STRUCTURE (query);
+
+  if (nominal_bitrate) {
+    value = gst_structure_id_get_value (structure, GST_QUARK (NOMINAL_BITRATE));
+    *nominal_bitrate = g_value_get_uint (value);
+  }
+}