diff -r 000000000000 -r 0e761a78d257 gstreamer_core/gst/gstevent.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gstreamer_core/gst/gstevent.c	Thu Dec 17 08:53:32 2009 +0200
@@ -0,0 +1,1072 @@
+/* GStreamer
+ * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
+ *                    2000 Wim Taymans <wim.taymans@chello.be>
+ *                    2005 Wim Taymans <wim@fluendo.com>
+ *
+ * gstevent.c: GstEvent subsystem
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * 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.
+ */
+
+/**
+ * SECTION:gstevent
+ * @short_description: Structure describing events that are passed up and down
+ *                     a pipeline
+ * @see_also: #GstPad, #GstElement
+ *
+ * The event class provides factory methods to construct and functions query
+ * (parse) events.
+ *
+ * Events are usually created with gst_event_new_*() which takes event-type
+ * specific parameters as arguments.
+ * To send an event application will usually use gst_element_send_event() and
+ * elements will use gst_pad_send_event() or gst_pad_push_event().
+ * The event should be unreffed with gst_event_unref() if it has not been sent.
+ *
+ * Events that have been received can be parsed with their respective 
+ * gst_event_parse_*() functions. It is valid to pass %NULL for unwanted details.
+ *
+ * Events are passed between elements in parallel to the data stream. Some events
+ * are serialized with buffers, others are not. Some events only travel downstream,
+ * others only upstream. Some events can travel both upstream and downstream. 
+ * 
+ * The events are used to signal special conditions in the datastream such as
+ * EOS (end of stream) or the start of a new stream-segment.
+ * Events are also used to flush the pipeline of any pending data.
+ *
+ * Most of the event API is used inside plugins. Applications usually only 
+ * construct and use seek events. 
+ * To do that gst_event_new_seek() is used to create a seek event. It takes
+ * the needed parameters to specity seeking time and mode.
+ * <example>
+ * <title>performing a seek on a pipeline</title>
+ *   <programlisting>
+ *   GstEvent *event;
+ *   gboolean result;
+ *   ...
+ *   // construct a seek event to play the media from second 2 to 5, flush
+ *   // the pipeline to decrease latency.
+ *   event = gst_event_new_seek (1.0, 
+ *      GST_FORMAT_TIME, 
+ *      GST_SEEK_FLAG_FLUSH,
+ *      GST_SEEK_TYPE_SET, 2 * GST_SECOND,
+ *      GST_SEEK_TYPE_SET, 5 * GST_SECOND);
+ *   ...
+ *   result = gst_element_send_event (pipeline, event);
+ *   if (!result)
+ *     g_warning ("seek failed");
+ *   ...
+ *   </programlisting>
+ * </example>
+ *
+ * Last reviewed on 2006-09-6 (0.10.10)
+ */
+
+
+#include "gst_private.h"
+#include <string.h>             /* memcpy */
+
+#include "gstinfo.h"
+#include "gstevent.h"
+#include "gstenumtypes.h"
+#include "gstutils.h"
+
+static void gst_event_init (GTypeInstance * instance, gpointer g_class);
+static void gst_event_class_init (gpointer g_class, gpointer class_data);
+static void gst_event_finalize (GstEvent * event);
+static GstEvent *_gst_event_copy (GstEvent * event);
+
+static GstMiniObjectClass *parent_class = NULL;
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+void
+_gst_event_initialize (void)
+{
+  g_type_class_ref (gst_event_get_type ());
+  g_type_class_ref (gst_seek_flags_get_type ());
+  g_type_class_ref (gst_seek_type_get_type ());
+}
+
+typedef struct
+{
+  const gint type;
+  const gchar *name;
+  GQuark quark;
+} GstEventQuarks;
+
+static GstEventQuarks event_quarks[] = {
+  {GST_EVENT_UNKNOWN, "unknown", 0},
+  {GST_EVENT_FLUSH_START, "flush-start", 0},
+  {GST_EVENT_FLUSH_STOP, "flush-stop", 0},
+  {GST_EVENT_EOS, "eos", 0},
+  {GST_EVENT_NEWSEGMENT, "newsegment", 0},
+  {GST_EVENT_TAG, "tag", 0},
+  {GST_EVENT_BUFFERSIZE, "buffersize", 0},
+  {GST_EVENT_QOS, "qos", 0},
+  {GST_EVENT_SEEK, "seek", 0},
+  {GST_EVENT_NAVIGATION, "navigation", 0},
+  {GST_EVENT_LATENCY, "latency", 0},
+  {GST_EVENT_CUSTOM_UPSTREAM, "custom-upstream", 0},
+  {GST_EVENT_CUSTOM_DOWNSTREAM, "custom-downstream", 0},
+  {GST_EVENT_CUSTOM_DOWNSTREAM_OOB, "custom-downstream-oob", 0},
+  {GST_EVENT_CUSTOM_BOTH, "custom-both", 0},
+  {GST_EVENT_CUSTOM_BOTH_OOB, "custom-both-oob", 0},
+
+  {0, NULL, 0}
+};
+
+/**
+ * gst_event_type_get_name:
+ * @type: the event type
+ *
+ * Get a printable name for the given event type. Do not modify or free.
+ *
+ * Returns: a reference to the static name of the event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+const gchar *
+gst_event_type_get_name (GstEventType type)
+{
+  gint i;
+
+  for (i = 0; event_quarks[i].name; i++) {
+    if (type == event_quarks[i].type)
+      return event_quarks[i].name;
+  }
+  return "unknown";
+}
+
+/**
+ * gst_event_type_to_quark:
+ * @type: the event type
+ *
+ * Get the unique quark for the given event type.
+ *
+ * Returns: the quark associated with the event type
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GQuark
+gst_event_type_to_quark (GstEventType type)
+{
+  gint i;
+
+  for (i = 0; event_quarks[i].name; i++) {
+    if (type == event_quarks[i].type)
+      return event_quarks[i].quark;
+  }
+  return 0;
+}
+
+/**
+ * gst_event_type_get_flags:
+ * @type: a #GstEventType
+ *
+ * Gets the #GstEventTypeFlags associated with @type.
+ *
+ * Returns: a #GstEventTypeFlags.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEventTypeFlags
+gst_event_type_get_flags (GstEventType type)
+{
+  GstEventTypeFlags ret;
+
+  ret = type & ((1 << GST_EVENT_TYPE_SHIFT) - 1);
+
+  return ret;
+}
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+GType
+gst_event_get_type (void)
+{
+  static GType _gst_event_type = 0;
+  int i;
+
+  if (G_UNLIKELY (_gst_event_type == 0)) {
+    static const GTypeInfo event_info = {
+      sizeof (GstEventClass),
+      NULL,
+      NULL,
+      gst_event_class_init,
+      NULL,
+      NULL,
+      sizeof (GstEvent),
+      0,
+      gst_event_init,
+      NULL
+    };
+
+    _gst_event_type = g_type_register_static (GST_TYPE_MINI_OBJECT,
+        "GstEvent", &event_info, 0);
+
+    for (i = 0; event_quarks[i].name; i++) {
+      event_quarks[i].quark = g_quark_from_static_string (event_quarks[i].name);
+    }
+  }
+
+  return _gst_event_type;
+}
+
+static void
+gst_event_class_init (gpointer g_class, gpointer class_data)
+{
+  GstEventClass *event_class = GST_EVENT_CLASS (g_class);
+
+  parent_class = g_type_class_peek_parent (g_class);
+
+  event_class->mini_object_class.copy =
+      (GstMiniObjectCopyFunction) _gst_event_copy;
+  event_class->mini_object_class.finalize =
+      (GstMiniObjectFinalizeFunction) gst_event_finalize;
+}
+
+static void
+gst_event_init (GTypeInstance * instance, gpointer g_class)
+{
+  GstEvent *event;
+
+  event = GST_EVENT (instance);
+
+  GST_EVENT_TIMESTAMP (event) = GST_CLOCK_TIME_NONE;
+}
+
+static void
+gst_event_finalize (GstEvent * event)
+{
+  g_return_if_fail (event != NULL);
+  g_return_if_fail (GST_IS_EVENT (event));
+
+  GST_CAT_LOG (GST_CAT_EVENT, "freeing event %p type %s", event,
+      GST_EVENT_TYPE_NAME (event));
+
+  if (GST_EVENT_SRC (event)) {
+    gst_object_unref (GST_EVENT_SRC (event));
+    GST_EVENT_SRC (event) = NULL;
+  }
+  if (event->structure) {
+    gst_structure_set_parent_refcount (event->structure, NULL);
+    gst_structure_free (event->structure);
+  }
+
+  GST_MINI_OBJECT_CLASS (parent_class)->finalize (GST_MINI_OBJECT (event));
+}
+
+static GstEvent *
+_gst_event_copy (GstEvent * event)
+{
+  GstEvent *copy;
+
+  copy = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
+
+  GST_EVENT_TYPE (copy) = GST_EVENT_TYPE (event);
+  GST_EVENT_TIMESTAMP (copy) = GST_EVENT_TIMESTAMP (event);
+
+  if (GST_EVENT_SRC (event)) {
+    GST_EVENT_SRC (copy) = gst_object_ref (GST_EVENT_SRC (event));
+  }
+  if (event->structure) {
+    copy->structure = gst_structure_copy (event->structure);
+    gst_structure_set_parent_refcount (copy->structure,
+        &copy->mini_object.refcount);
+  }
+  return copy;
+}
+
+static GstEvent *
+gst_event_new (GstEventType type)
+{
+  GstEvent *event;
+
+  event = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
+
+  GST_CAT_DEBUG (GST_CAT_EVENT, "creating new event %p %s %d", event,
+      gst_event_type_get_name (type), type);
+
+  event->type = type;
+  event->src = NULL;
+  event->structure = NULL;
+
+  return event;
+}
+
+/**
+ * gst_event_new_custom:
+ * @type: The type of the new event
+ * @structure: The structure for the event. The event will take ownership of
+ * the structure.
+ *
+ * Create a new custom-typed event. This can be used for anything not
+ * handled by other event-specific functions to pass an event to another
+ * element.
+ *
+ * Make sure to allocate an event type with the #GST_EVENT_MAKE_TYPE macro,
+ * assigning a free number and filling in the correct direction and
+ * serialization flags.
+ *
+ * New custom events can also be created by subclassing the event type if
+ * needed.
+ *
+ * Returns: The new custom event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_custom (GstEventType type, GstStructure * structure)
+{
+  GstEvent *event;
+
+  /* structure must not have a parent */
+  if (structure)
+    g_return_val_if_fail (structure->parent_refcount == NULL, NULL);
+
+  event = gst_event_new (type);
+  if (structure) {
+    gst_structure_set_parent_refcount (structure, &event->mini_object.refcount);
+    event->structure = structure;
+  }
+  return event;
+}
+
+/**
+ * gst_event_get_structure:
+ * @event: The #GstEvent.
+ *
+ * Access the structure of the event.
+ *
+ * Returns: The structure of the event. The structure is still
+ * owned by the event, which means that you should not free it and
+ * that the pointer becomes invalid when you free the event.
+ *
+ * MT safe.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+const GstStructure *
+gst_event_get_structure (GstEvent * event)
+{
+  g_return_val_if_fail (GST_IS_EVENT (event), NULL);
+
+  return event->structure;
+}
+
+/**
+ * gst_event_new_flush_start:
+ *
+ * Allocate a new flush start event. The flush start event can be sent
+ * upstream and downstream and travels out-of-bounds with the dataflow.
+ *
+ * It marks pads as being flushing and will make them return
+ * #GST_FLOW_WRONG_STATE when used for data flow with gst_pad_push(),
+ * gst_pad_chain(), gst_pad_alloc_buffer(), gst_pad_get_range() and
+ * gst_pad_pull_range(). Any event (except a #GST_EVENT_FLUSH_STOP) received
+ * on a flushing pad will return %FALSE immediately.
+ *
+ * Elements should unlock any blocking functions and exit their streaming
+ * functions as fast as possible when this event is received.
+ *
+ * This event is typically generated after a seek to flush out all queued data
+ * in the pipeline so that the new media is played as soon as possible.
+ *
+ * Returns: A new flush start event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_flush_start (void)
+{
+  return gst_event_new (GST_EVENT_FLUSH_START);
+}
+
+/**
+ * gst_event_new_flush_stop:
+ *
+ * Allocate a new flush stop event. The flush stop event can be sent
+ * upstream and downstream and travels out-of-bounds with the dataflow.
+ * It is typically sent after sending a FLUSH_START event to make the
+ * pads accept data again.
+ *
+ * Elements can process this event synchronized with the dataflow since
+ * the preceeding FLUSH_START event stopped the dataflow.
+ *
+ * This event is typically generated to complete a seek and to resume
+ * dataflow.
+ *
+ * Returns: A new flush stop event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_flush_stop (void)
+{
+  return gst_event_new (GST_EVENT_FLUSH_STOP);
+}
+
+/**
+ * gst_event_new_eos:
+ *
+ * Create a new EOS event. The eos event can only travel downstream
+ * synchronized with the buffer flow. Elements that receive the EOS
+ * event on a pad can return #GST_FLOW_UNEXPECTED as a #GstFlowReturn
+ * when data after the EOS event arrives.
+ *
+ * The EOS event will travel down to the sink elements in the pipeline
+ * which will then post the #GST_MESSAGE_EOS on the bus after they have
+ * finished playing any buffered data.
+ *
+ * When all sinks have posted an EOS message, an EOS message is
+ * forwarded to the application.
+ *
+ * Returns: The new EOS event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_eos (void)
+{
+  return gst_event_new (GST_EVENT_EOS);
+}
+
+/**
+ * gst_event_new_new_segment:
+ * @update: is this segment an update to a previous one
+ * @rate: a new rate for playback
+ * @format: The format of the segment values
+ * @start: the start value of the segment
+ * @stop: the stop value of the segment
+ * @position: stream position
+ *
+ * Allocate a new newsegment event with the given format/
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+values tripplets
+ *
+ * This method calls gst_event_new_new_segment_full() passing a default
+ * value of 1.0 for applied_rate
+ *
+ * Returns: A new newsegment event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_new_segment (gboolean update, gdouble rate, GstFormat format,
+    gint64 start, gint64 stop, gint64 position)
+{
+  return gst_event_new_new_segment_full (update, rate, 1.0, format, start,
+      stop, position);
+}
+
+/**
+ * gst_event_parse_new_segment:
+ * @event: The event to query
+ * @update: A pointer to the update flag of the segment
+ * @rate: A pointer to the rate of the segment
+ * @format: A pointer to the format of the newsegment values
+ * @start: A pointer to store the start value in
+ * @stop: A pointer to store the stop value in
+ * @position: A pointer to store the stream time in
+ *
+ * Get the update flag, rate, format, start, stop and position in the 
+ * newsegment event. In general, gst_event_parse_new_segment_full() should
+ * be used instead of this, to also retrieve the applied_rate value of the
+ * segment. See gst_event_new_new_segment_full() for a full description 
+ * of the newsegment event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_new_segment (GstEvent * event, gboolean * update,
+    gdouble * rate, GstFormat * format, gint64 * start,
+    gint64 * stop, gint64 * position)
+{
+  gst_event_parse_new_segment_full (event, update, rate, NULL, format, start,
+      stop, position);
+}
+
+/**
+ * gst_event_new_new_segment_full:
+ * @update: Whether this segment is an update to a previous one
+ * @rate: A new rate for playback
+ * @applied_rate: The rate factor which has already been applied
+ * @format: The format of the segment values
+ * @start: The start value of the segment
+ * @stop: The stop value of the segment
+ * @position: stream position
+ *
+ * Allocate a new newsegment event with the given format/values triplets.
+ *
+ * The newsegment event marks the range of buffers to be processed. All
+ * data not within the segment range is not to be processed. This can be
+ * used intelligently by plugins to apply more efficient methods of skipping
+ * unneeded data.
+ *
+ * The position value of the segment is used in conjunction with the start
+ * value to convert the buffer timestamps into the stream time. This is 
+ * usually done in sinks to report the current stream_time. 
+ * @position represents the stream_time of a buffer carrying a timestamp of 
+ * @start. @position cannot be -1.
+ *
+ * @start cannot be -1, @stop can be -1. If there
+ * is a valid @stop given, it must be greater or equal the @start, including 
+ * when the indicated playback @rate is < 0.
+ *
+ * The @applied_rate value provides information about any rate adjustment that
+ * has already been made to the timestamps and content on the buffers of the 
+ * stream. (@rate * @applied_rate) should always equal the rate that has been 
+ * requested for playback. For example, if an element has an input segment 
+ * with intended playback @rate of 2.0 and applied_rate of 1.0, it can adjust 
+ * incoming timestamps and buffer content by half and output a newsegment event 
+ * with @rate of 1.0 and @applied_rate of 2.0
+ *
+ * After a newsegment event, the buffer stream time is calculated with:
+ *
+ *   position + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)
+ *
+ * Returns: A new newsegment event.
+ *
+ * Since: 0.10.6
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_new_segment_full (gboolean update, gdouble rate,
+    gdouble applied_rate, GstFormat format, gint64 start, gint64 stop,
+    gint64 position)
+{
+  g_return_val_if_fail (rate != 0.0, NULL);
+  g_return_val_if_fail (applied_rate != 0.0, NULL);
+
+  if (format == GST_FORMAT_TIME) {
+    GST_CAT_INFO (GST_CAT_EVENT,
+        "creating newsegment update %d, rate %lf, format GST_FORMAT_TIME, "
+        "start %" GST_TIME_FORMAT ", stop %" GST_TIME_FORMAT
+        ", position %" GST_TIME_FORMAT,
+        update, rate, GST_TIME_ARGS (start),
+        GST_TIME_ARGS (stop), GST_TIME_ARGS (position));
+  } else {
+    GST_CAT_INFO (GST_CAT_EVENT,
+        "creating newsegment update %d, rate %lf, format %d, "
+        "start %" G_GINT64_FORMAT ", stop %" G_GINT64_FORMAT ", position %"
+        G_GINT64_FORMAT, update, rate, format, start, stop, position);
+  }
+
+  g_return_val_if_fail (position != -1, NULL);
+  g_return_val_if_fail (start != -1, NULL);
+  if (stop != -1)
+    g_return_val_if_fail (start <= stop, NULL);
+
+  return gst_event_new_custom (GST_EVENT_NEWSEGMENT,
+      gst_structure_new ("GstEventNewsegment",
+          "update", G_TYPE_BOOLEAN, update,
+          "rate", G_TYPE_DOUBLE, rate,
+          "applied_rate", G_TYPE_DOUBLE, applied_rate,
+          "format", GST_TYPE_FORMAT, format,
+          "start", G_TYPE_INT64, start,
+          "stop", G_TYPE_INT64, stop,
+          "position", G_TYPE_INT64, position, NULL));
+}
+
+/**
+ * gst_event_parse_new_segment_full:
+ * @event: The event to query
+ * @update: A pointer to the update flag of the segment
+ * @rate: A pointer to the rate of the segment
+ * @applied_rate: A pointer to the applied_rate of the segment
+ * @format: A pointer to the format of the newsegment values
+ * @start: A pointer to store the start value in
+ * @stop: A pointer to store the stop value in
+ * @position: A pointer to store the stream time in
+ *
+ * Get the update, rate, applied_rate, format, start, stop and 
+ * position in the newsegment event. See gst_event_new_new_segment_full() 
+ * for a full description of the newsegment event.
+ *
+ * Since: 0.10.6
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_new_segment_full (GstEvent * event, gboolean * update,
+    gdouble * rate, gdouble * applied_rate, GstFormat * format,
+    gint64 * start, gint64 * stop, gint64 * position)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_NEWSEGMENT);
+
+  structure = gst_event_get_structure (event);
+  if (G_LIKELY (update))
+    *update =
+        g_value_get_boolean (gst_structure_get_value (structure, "update"));
+  if (G_LIKELY (rate))
+    *rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
+  if (G_LIKELY (applied_rate))
+    *applied_rate =
+        g_value_get_double (gst_structure_get_value (structure,
+            "applied_rate"));
+  if (G_LIKELY (format))
+    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
+  if (G_LIKELY (start))
+    *start = g_value_get_int64 (gst_structure_get_value (structure, "start"));
+  if (G_LIKELY (stop))
+    *stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
+  if (G_LIKELY (position))
+    *position =
+        g_value_get_int64 (gst_structure_get_value (structure, "position"));
+}
+
+/**
+ * gst_event_new_tag:
+ * @taglist: metadata list
+ *
+ * Generates a metadata tag event from the given @taglist.
+ *
+ * Returns: a new #GstEvent
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_tag (GstTagList * taglist)
+{
+  g_return_val_if_fail (taglist != NULL, NULL);
+
+  return gst_event_new_custom (GST_EVENT_TAG, (GstStructure *) taglist);
+}
+
+/**
+ * gst_event_parse_tag:
+ * @event: a tag event
+ * @taglist: pointer to metadata list
+ *
+ * Parses a tag @event and stores the results in the given @taglist location.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_tag (GstEvent * event, GstTagList ** taglist)
+{
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TAG);
+
+  if (taglist)
+    *taglist = (GstTagList *) event->structure;
+}
+
+/* buffersize event */
+/**
+ * gst_event_new_buffer_size:
+ * @format: buffer format
+ * @minsize: minimum buffer size
+ * @maxsize: maximum buffer size
+ * @async: thread behavior
+ *
+ * Create a new buffersize event. The event is sent downstream and notifies
+ * elements that they should provide a buffer of the specified dimensions.
+ *
+ * When the @async flag is set, a thread boundary is prefered.
+ *
+ * Returns: a new #GstEvent
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_buffer_size (GstFormat format, gint64 minsize,
+    gint64 maxsize, gboolean async)
+{
+  GST_CAT_INFO (GST_CAT_EVENT,
+      "creating buffersize format %d, minsize %" G_GINT64_FORMAT
+      ", maxsize %" G_GINT64_FORMAT ", async %d", format,
+      minsize, maxsize, async);
+
+  return gst_event_new_custom (GST_EVENT_BUFFERSIZE,
+      gst_structure_new ("GstEventBufferSize",
+          "format", GST_TYPE_FORMAT, format,
+          "minsize", G_TYPE_INT64, minsize,
+          "maxsize", G_TYPE_INT64, maxsize,
+          "async", G_TYPE_BOOLEAN, async, NULL));
+}
+
+/**
+ * gst_event_parse_buffer_size:
+ * @event: The event to query
+ * @format: A pointer to store the format in
+ * @minsize: A pointer to store the minsize in
+ * @maxsize: A pointer to store the maxsize in
+ * @async: A pointer to store the async-flag in
+ *
+ * Get the format, minsize, maxsize and async-flag in the buffersize event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
+    gint64 * minsize, gint64 * maxsize, gboolean * async)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_BUFFERSIZE);
+
+  structure = gst_event_get_structure (event);
+  if (format)
+    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
+  if (minsize)
+    *minsize =
+        g_value_get_int64 (gst_structure_get_value (structure, "minsize"));
+  if (maxsize)
+    *maxsize =
+        g_value_get_int64 (gst_structure_get_value (structure, "maxsize"));
+  if (async)
+    *async = g_value_get_boolean (gst_structure_get_value (structure, "async"));
+}
+
+/**
+ * gst_event_new_qos:
+ * @proportion: the proportion of the qos message
+ * @diff: The time difference of the last Clock sync
+ * @timestamp: The timestamp of the buffer
+ *
+ * Allocate a new qos event with the given values.
+ * The QOS event is generated in an element that wants an upstream
+ * element to either reduce or increase its rate because of
+ * high/low CPU load or other resource usage such as network performance.
+ * Typically sinks generate these events for each buffer they receive.
+ *
+ * @proportion indicates the real-time performance of the streaming in the
+ * element that generated the QoS event (usually the sink). The value is
+ * generally computed based on more long term statistics about the streams
+ * timestamps compared to the clock.
+ * A value < 1.0 indicates that the upstream element is producing data faster
+ * than real-time. A value > 1.0 indicates that the upstream element is not
+ * producing data fast enough. 1.0 is the ideal @proportion value. The
+ * proportion value can safely be used to lower or increase the quality of
+ * the element.
+ *
+ * @diff is the difference against the clock in running time of the last
+ * buffer that caused the element to generate the QOS event. A negative value
+ * means that the buffer with @timestamp arrived in time. A positive value
+ * indicates how late the buffer with @timestamp was.
+ *
+ * @timestamp is the timestamp of the last buffer that cause the element
+ * to generate the QOS event. It is expressed in running time and thus an ever
+ * increasing value.
+ *
+ * The upstream element can use the @diff and @timestamp values to decide
+ * whether to process more buffers. For possitive @diff, all buffers with
+ * timestamp <= @timestamp + @diff will certainly arrive late in the sink
+ * as well. 
+ *
+ * The application can use general event probes to intercept the QoS
+ * event and implement custom application specific QoS handling.
+ *
+ * Returns: A new QOS event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_qos (gdouble proportion, GstClockTimeDiff diff,
+    GstClockTime timestamp)
+{
+  GST_CAT_INFO (GST_CAT_EVENT,
+      "creating qos proportion %lf, diff %" G_GINT64_FORMAT
+      ", timestamp %" GST_TIME_FORMAT, proportion,
+      diff, GST_TIME_ARGS (timestamp));
+
+  return gst_event_new_custom (GST_EVENT_QOS,
+      gst_structure_new ("GstEventQOS",
+          "proportion", G_TYPE_DOUBLE, proportion,
+          "diff", G_TYPE_INT64, diff,
+          "timestamp", G_TYPE_UINT64, timestamp, NULL));
+}
+
+/**
+ * gst_event_parse_qos:
+ * @event: The event to query
+ * @proportion: A pointer to store the proportion in
+ * @diff: A pointer to store the diff in
+ * @timestamp: A pointer to store the timestamp in
+ *
+ * Get the proportion, diff and timestamp in the qos event. See
+ * gst_event_new_qos() for more information about the different QoS values.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_qos (GstEvent * event, gdouble * proportion,
+    GstClockTimeDiff * diff, GstClockTime * timestamp)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_QOS);
+
+  structure = gst_event_get_structure (event);
+  if (proportion)
+    *proportion =
+        g_value_get_double (gst_structure_get_value (structure, "proportion"));
+  if (diff)
+    *diff = g_value_get_int64 (gst_structure_get_value (structure, "diff"));
+  if (timestamp)
+    *timestamp =
+        g_value_get_uint64 (gst_structure_get_value (structure, "timestamp"));
+}
+
+/**
+ * gst_event_new_seek:
+ * @rate: The new playback rate
+ * @format: The format of the seek values
+ * @flags: The optional seek flags
+ * @start_type: The type and flags for the new start position
+ * @start: The value of the new start position
+ * @stop_type: The type and flags for the new stop position
+ * @stop: The value of the new stop position
+ *
+ * Allocate a new seek event with the given parameters.
+ *
+ * The seek event configures playback of the pipeline between @start to @stop
+ * at the speed given in @rate, also called a playback segment.
+ * The @start and @stop values are expressed in @format.
+ *
+ * A @rate of 1.0 means normal playback rate, 2.0 means double speed.
+ * Negatives values means backwards playback. A value of 0.0 for the
+ * rate is not allowed and should be accomplished instead by PAUSING the
+ * pipeline.
+ *
+ * A pipeline has a default playback segment configured with a start
+ * position of 0, a stop position of -1 and a rate of 1.0. The currently
+ * configured playback segment can be queried with #GST_QUERY_SEGMENT. 
+ *
+ * @start_type and @stop_type specify how to adjust the currently configured 
+ * start and stop fields in @segment. Adjustments can be made relative or
+ * absolute to the last configured values. A type of #GST_SEEK_TYPE_NONE means
+ * that the position should not be updated.
+ *
+ * When the rate is positive and @start has been updated, playback will start
+ * from the newly configured start position. 
+ *
+ * For negative rates, playback will start from the newly configured stop
+ * position (if any). If the stop position if updated, it must be different from
+ * -1 for negative rates.
+ *
+ * It is not possible to seek relative to the current playback position, to do
+ * this, PAUSE the pipeline, query the current playback position with
+ * #GST_QUERY_POSITION and update the playback segment current position with a
+ * #GST_SEEK_TYPE_SET to the desired position.
+ *
+ * Returns: A new seek event.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+GstEvent *
+gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
+    GstSeekType start_type, gint64 start, GstSeekType stop_type, gint64 stop)
+{
+  g_return_val_if_fail (rate != 0.0, NULL);
+
+  if (format == GST_FORMAT_TIME) {
+    GST_CAT_INFO (GST_CAT_EVENT,
+        "creating seek rate %lf, format TIME, flags %d, "
+        "start_type %d, start %" GST_TIME_FORMAT ", "
+        "stop_type %d, stop %" GST_TIME_FORMAT,
+        rate, flags, start_type, GST_TIME_ARGS (start),
+        stop_type, GST_TIME_ARGS (stop));
+  } else {
+    GST_CAT_INFO (GST_CAT_EVENT,
+        "creating seek rate %lf, format %d, flags %d, "
+        "start_type %d, start %" G_GINT64_FORMAT ", "
+        "stop_type %d, stop %" G_GINT64_FORMAT,
+        rate, format, flags, start_type, start, stop_type, stop);
+  }
+
+  return gst_event_new_custom (GST_EVENT_SEEK,
+      gst_structure_new ("GstEventSeek", "rate", G_TYPE_DOUBLE, rate,
+          "format", GST_TYPE_FORMAT, format,
+          "flags", GST_TYPE_SEEK_FLAGS, flags,
+          "cur_type", GST_TYPE_SEEK_TYPE, start_type,
+          "cur", G_TYPE_INT64, start,
+          "stop_type", GST_TYPE_SEEK_TYPE, stop_type,
+          "stop", G_TYPE_INT64, stop, NULL));
+}
+
+/**
+ * gst_event_parse_seek:
+ * @event: a seek event
+ * @rate: result location for the rate
+ * @format: result location for the stream format
+ * @flags:  result location for the #GstSeekFlags
+ * @start_type: result location for the #GstSeekType of the start position
+ * @start: result location for the start postion expressed in @format
+ * @stop_type:  result location for the #GstSeekType of the stop position
+ * @stop: result location for the stop postion expressed in @format
+ *
+ * Parses a seek @event and stores the results in the given result locations.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_seek (GstEvent * event, gdouble * rate,
+    GstFormat * format, GstSeekFlags * flags, GstSeekType * start_type,
+    gint64 * start, GstSeekType * stop_type, gint64 * stop)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEEK);
+
+  structure = gst_event_get_structure (event);
+  if (rate)
+    *rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
+  if (format)
+    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
+  if (flags)
+    *flags = g_value_get_flags (gst_structure_get_value (structure, "flags"));
+  if (start_type)
+    *start_type =
+        g_value_get_enum (gst_structure_get_value (structure, "cur_type"));
+  if (start)
+    *start = g_value_get_int64 (gst_structure_get_value (structure, "cur"));
+  if (stop_type)
+    *stop_type =
+        g_value_get_enum (gst_structure_get_value (structure, "stop_type"));
+  if (stop)
+    *stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
+}
+
+/**
+ * gst_event_new_navigation:
+ * @structure: description of the event
+ *
+ * Create a new navigation event from the given description.
+ *
+ * Returns: a new #GstEvent
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_navigation (GstStructure * structure)
+{
+  g_return_val_if_fail (structure != NULL, NULL);
+
+  return gst_event_new_custom (GST_EVENT_NAVIGATION, structure);
+}
+
+/**
+ * gst_event_new_latency:
+ * @latency: the new latency value
+ *
+ * Create a new latency event. The event is sent upstream from the sinks and
+ * notifies elements that they should add an additional @latency to the
+ * timestamps before synchronising against the clock.
+ *
+ * The latency is mostly used in live sinks and is always expressed in
+ * the time format.
+ *
+ * Returns: a new #GstEvent
+ *
+ * Since: 0.10.12
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstEvent *
+gst_event_new_latency (GstClockTime latency)
+{
+  GST_CAT_INFO (GST_CAT_EVENT,
+      "creating latency event %" GST_TIME_FORMAT, GST_TIME_ARGS (latency));
+
+  return gst_event_new_custom (GST_EVENT_LATENCY,
+      gst_structure_new ("GstEventLatency",
+          "latency", G_TYPE_UINT64, latency, NULL));
+}
+
+/**
+ * gst_event_parse_latency:
+ * @event: The event to query
+ * @latency: A pointer to store the latency in.
+ *
+ * Get the latency in the latency event.
+ *
+ * Since: 0.10.12
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_event_parse_latency (GstEvent * event, GstClockTime * latency)
+{
+  const GstStructure *structure;
+
+  g_return_if_fail (GST_IS_EVENT (event));
+  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_LATENCY);
+
+  structure = gst_event_get_structure (event);
+  if (latency)
+    *latency =
+        g_value_get_uint64 (gst_structure_get_value (structure, "latency"));
+}