Re-factor the gconfaudiosink into a "GstSwitchSink" base class and a child that implements the GConf key monitoring. ...

Original commit message from CVS:
* ext/gconf/Makefile.am:
* ext/gconf/gconf.c: (gst_gconf_get_string),
(gst_gconf_get_key_for_sink_profile), (gst_gconf_set_string),
(gst_gconf_render_bin_with_default):
* ext/gconf/gconf.h:
* ext/gconf/gstgconfaudiosink.c: (gst_gconf_audio_sink_base_init),
(gst_gconf_audio_sink_reset), (gst_gconf_audio_sink_init),
(gst_gconf_audio_sink_dispose), (do_change_child),
(gst_gconf_switch_profile), (gst_gconf_audio_sink_set_property),
(cb_change_child), (gst_gconf_audio_sink_change_state):
* ext/gconf/gstgconfaudiosink.h:
* ext/gconf/gstswitchsink.c: (gst_switch_sink_base_init),
(gst_switch_sink_class_init), (gst_switch_sink_reset),
(gst_switch_sink_init), (gst_switch_sink_dispose),
(gst_switch_commit_new_kid), (gst_switch_sink_set_child),
(gst_switch_sink_set_property), (gst_switch_sink_handle_event),
(gst_switch_sink_get_property), (gst_switch_sink_change_state):
* ext/gconf/gstswitchsink.h:
* gst/autodetect/gstautoaudiosink.c:
(gst_auto_audio_sink_class_init), (gst_auto_audio_sink_dispose),
(gst_auto_audio_sink_clear_kid), (gst_auto_audio_sink_reset),
(gst_auto_audio_sink_detect):
* gst/autodetect/gstautovideosink.c:
(gst_auto_video_sink_class_init), (gst_auto_video_sink_dispose),
(gst_auto_video_sink_clear_kid), (gst_auto_video_sink_reset),
(gst_auto_video_sink_detect):
Re-factor the gconfaudiosink into a "GstSwitchSink" base class
and a child that implements the GConf key monitoring. The end goal of
this is an audio sink that can be changed on the fly, but at the
moment it still only changes on the next READY transition.

1 files changed, 265 insertions, 0 deletions

diff --git a/ext/gconf/gstswitchsink.c b/ext/gconf/gstswitchsink.c
new file mode 100644
index 00000000..d00336e9
--- /dev/null
+++ b/ext/gconf/gstswitchsink.c
@@ -0,0 +1,265 @@
+/* GStreamer
+ * (c) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net>
+ * (c) 2006 Jürg Billeter <j@bitron.ch>
+ * (c) 2007 Jan Schmidt <thaytan@noraisin.net>
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string.h>
+
+#include "gstswitchsink.h"
+
+GST_DEBUG_CATEGORY_STATIC (switch_debug);
+#define GST_CAT_DEFAULT switch_debug
+
+static void gst_switch_sink_dispose (GObject * object);
+static GstStateChangeReturn
+gst_switch_sink_change_state (GstElement * element, GstStateChange transition);
+
+enum
+{
+  PROP_0
+};
+
+GST_BOILERPLATE (GstSwitchSink, gst_switch_sink, GstBin, GST_TYPE_BIN);
+
+static void gst_switch_sink_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec);
+static void gst_switch_sink_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec);
+
+static void
+gst_switch_sink_base_init (gpointer klass)
+{
+  GST_DEBUG_CATEGORY_INIT (switch_debug, "switchsink", 0, "switchsink element");
+}
+
+static void
+gst_switch_sink_class_init (GstSwitchSinkClass * klass)
+{
+  GObjectClass *oklass = G_OBJECT_CLASS (klass);
+  GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
+  GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
+      GST_PAD_SINK,
+      GST_PAD_ALWAYS,
+      GST_STATIC_CAPS_ANY);
+  GstPadTemplate *child_pad_templ;
+
+  oklass->set_property = gst_switch_sink_set_property;
+  oklass->get_property = gst_switch_sink_get_property;
+  oklass->dispose = gst_switch_sink_dispose;
+  eklass->change_state = gst_switch_sink_change_state;
+
+  /* Provide a default pad template if the child didn't */
+  child_pad_templ = gst_element_class_get_pad_template (eklass, "sink");
+  if (child_pad_templ == NULL) {
+    gst_element_class_add_pad_template (eklass,
+        gst_static_pad_template_get (&sink_template));
+  }
+}
+
+static void
+gst_switch_sink_reset (GstSwitchSink * sink)
+{
+  /* fakesink */
+  if (sink->kid == NULL) {
+    gst_switch_sink_set_child (sink, NULL);
+  }
+}
+
+static void
+gst_switch_sink_init (GstSwitchSink * sink, GstSwitchSinkClass * g_class)
+{
+  sink->pad = gst_ghost_pad_new_no_target ("sink", GST_PAD_SINK);
+  gst_element_add_pad (GST_ELEMENT (sink), sink->pad);
+
+  gst_switch_sink_reset (sink);
+}
+
+static void
+gst_switch_sink_dispose (GObject * object)
+{
+  GstSwitchSink *sink = GST_SWITCH_SINK (object);
+  GstElement **p_kid = &sink->kid;
+
+  gst_object_replace ((GstObject **) p_kid, NULL);
+
+  GST_CALL_PARENT (G_OBJECT_CLASS, dispose, (object));
+}
+
+gboolean
+gst_switch_commit_new_kid (GstSwitchSink * sink)
+{
+  GstPad *targetpad;
+  GstState cur_state;
+  GstElement *new_kid, *old_kid;
+  gboolean is_fakesink = FALSE;
+
+  /* need locking around member accesses */
+  GST_OBJECT_LOCK (sink);
+  cur_state = GST_STATE (sink);
+  new_kid = sink->new_kid;
+  sink->new_kid = NULL;
+  GST_OBJECT_UNLOCK (sink);
+
+  /* Fakesink by default if NULL is passed as the new child */
+  if (new_kid == NULL) {
+    GST_DEBUG_OBJECT (sink, "Replacing kid with fakesink");
+    new_kid = gst_element_factory_make ("fakesink", "testsink");
+    g_object_set (new_kid, "sync", TRUE, NULL);
+    is_fakesink = TRUE;
+  } else {
+    GST_DEBUG_OBJECT (sink, "Setting new kid");
+  }
+
+  if (gst_element_set_state (new_kid, cur_state) == GST_STATE_CHANGE_FAILURE) {
+    GST_ELEMENT_ERROR (sink, CORE, STATE_CHANGE, (NULL),
+        ("Failed to set state on new child."));
+    gst_object_unref (new_kid);
+    return FALSE;
+  }
+  gst_bin_add (GST_BIN (sink), new_kid);
+
+  /* Now, replace the existing child */
+  GST_OBJECT_LOCK (sink);
+  old_kid = sink->kid;
+  sink->kid = new_kid;
+  GST_OBJECT_UNLOCK (sink);
+
+  /* kill old element */
+  if (old_kid) {
+    GST_DEBUG_OBJECT (sink, "Removing old kid %" GST_PTR_FORMAT, old_kid);
+    gst_element_set_state (old_kid, GST_STATE_NULL);
+    gst_bin_remove (GST_BIN (sink), old_kid);
+  }
+
+  /* re-attach ghostpad */
+  GST_DEBUG_OBJECT (sink, "Creating new ghostpad");
+  targetpad = gst_element_get_pad (sink->kid, "sink");
+  gst_ghost_pad_set_target (GST_GHOST_PAD (sink->pad), targetpad);
+  gst_object_unref (targetpad);
+  GST_DEBUG_OBJECT (sink, "done changing child of switchsink");
+
+  /* FIXME: Push new-segment info and pre-roll buffer(s) into the kid */
+
+  /* Unblock the target pad if necessary */
+  if (sink->awaiting_block) {
+    gst_pad_set_blocked (sink->pad, FALSE);
+    sink->awaiting_block = FALSE;
+  }
+
+  return TRUE;
+}
+
+gboolean
+gst_switch_sink_set_child (GstSwitchSink * sink, GstElement * new_kid)
+{
+  GstState cur, next;
+  GstElement **p_kid;
+
+  /* Nothing to do if clearing the child and we don't have one anyway */
+  if (new_kid == NULL && sink->have_kid == FALSE)
+    return TRUE;
+
+  GST_OBJECT_LOCK (sink);
+  cur = GST_STATE (sink);
+  next = GST_STATE_NEXT (sink);
+  p_kid = &sink->new_kid;
+  gst_object_replace ((GstObject **) p_kid, (GstObject *) new_kid);
+  GST_OBJECT_UNLOCK (sink);
+
+  if (cur == GST_STATE_PAUSED && next == GST_STATE_READY) {
+    return gst_switch_commit_new_kid (sink);
+  }
+  /* Sometime, it would be lovely to allow sink changes even when
+   * already running, but this involves sending an appropriate new-segment
+   * and possibly prerolling etc */
+  /* FIXME: Block the pad and replace the kid when it completes */
+  if (cur > GST_STATE_READY || next == GST_STATE_PAUSED) {
+    GST_DEBUG_OBJECT (sink,
+        "Switch-sink is already running. Ignoring change of child.");
+    gst_object_unref (new_kid);
+    return TRUE;
+  }
+
+  return gst_switch_commit_new_kid (sink);
+}
+
+static void
+gst_switch_sink_set_property (GObject * object, guint prop_id,
+    const GValue * value, GParamSpec * pspec)
+{
+  GstSwitchSink *sink;
+
+  g_return_if_fail (GST_IS_SWITCH_SINK (object));
+
+  sink = GST_SWITCH_SINK (object);
+
+  switch (prop_id) {
+      break;
+    default:
+      break;
+  }
+}
+
+#if 0
+static gboolean
+gst_switch_sink_handle_event (GstPad * pad, GstEvent * event)
+{
+}
+#endif
+
+static void
+gst_switch_sink_get_property (GObject * object, guint prop_id,
+    GValue * value, GParamSpec * pspec)
+{
+  GstSwitchSink *sink;
+
+  g_return_if_fail (GST_IS_SWITCH_SINK (object));
+
+  sink = GST_SWITCH_SINK (object);
+
+  switch (prop_id) {
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+  }
+}
+
+static GstStateChangeReturn
+gst_switch_sink_change_state (GstElement * element, GstStateChange transition)
+{
+  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
+  GstSwitchSink *sink = GST_SWITCH_SINK (element);
+
+  ret = GST_CALL_PARENT_WITH_DEFAULT (GST_ELEMENT_CLASS, change_state,
+      (element, transition), GST_STATE_CHANGE_SUCCESS);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_READY_TO_NULL:
+      gst_switch_sink_reset (sink);
+      break;
+    default:
+      break;
+  }
+
+  return ret;
+}