1 files changed, 168 insertions, 0 deletions
diff --git a/shell/extensions/sugar-audio-manager.c b/shell/extensions/sugar-audio-manager.c
new file mode 100644
index 0000000..6f73cbc
--- /dev/null
+++ b/shell/extensions/sugar-audio-manager.c
@@ -0,0 +1,168 @@
+/* 
+ * Copyright (C) 2006 Red Hat, Inc
+ *
+ * Sugar is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Sugar 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <gst/gst.h>
+#include <gst/audio/mixerutils.h>
+#include <gst/interfaces/mixer.h>
+#include <gst/interfaces/propertyprobe.h>
+
+#include "sugar-audio-manager.h"
+
+struct _SugarAudioManagerPrivate
+{
+	GstMixer *mixer;
+	GstMixerTrack *track;
+	guint timer_id;
+};
+
+G_DEFINE_TYPE(SugarAudioManager, sugar_audio_manager, G_TYPE_OBJECT)
+
+#define SUGAR_AUDIO_MANAGER_GET_PRIVATE(object) (G_TYPE_INSTANCE_GET_PRIVATE ((object), SUGAR_TYPE_AUDIO_MANAGER, SugarAudioManagerPrivate))
+
+/* This is a modified version of code from gnome-control-center */
+
+static gboolean
+mixer_close_real(SugarAudioManager *manager)
+{
+	if (manager->priv->mixer != NULL)
+	{
+		gst_element_set_state(GST_ELEMENT(manager->priv->mixer), GST_STATE_NULL);
+		gst_object_unref(GST_OBJECT(manager->priv->mixer));	    
+		g_object_unref(G_OBJECT(manager->priv->track));
+		manager->priv->mixer = NULL;
+		manager->priv->track = NULL;
+	}
+	
+	manager->priv->timer_id = 0;
+
+	return FALSE;
+}
+
+static gboolean
+set_mixer_helper(GstMixer *mixer, gpointer user_data)
+{
+	const GList *tracks;
+
+	tracks = gst_mixer_list_tracks(mixer);
+
+	while (tracks != NULL) {
+		GstMixerTrack *track = GST_MIXER_TRACK(tracks->data);
+
+		if (GST_MIXER_TRACK_HAS_FLAG(track, GST_MIXER_TRACK_MASTER)) {
+			SugarAudioManager *manager;
+
+			manager = SUGAR_AUDIO_MANAGER(user_data);
+
+			manager->priv->mixer = mixer;
+			manager->priv->track = track;
+
+			/* no need to ref the mixer element */
+			g_object_ref(manager->priv->track);
+			return TRUE;
+		}
+
+		tracks = tracks->next;
+	}
+
+	return FALSE;
+}
+
+static gboolean
+mixer_open(SugarAudioManager *manager)
+{
+	GList *mixer_list;
+
+	if (manager->priv->timer_id != 0) {
+		g_source_remove (manager->priv->timer_id);
+		manager->priv->timer_id = 0;
+		return TRUE;
+	}
+		
+	mixer_list = gst_audio_default_registry_mixer_filter
+					(set_mixer_helper, TRUE, manager);
+
+	if (mixer_list == NULL)
+		return FALSE;
+
+	/* do not unref the mixer as we keep the ref for manager->priv->mixer */
+	g_list_free (mixer_list);
+
+	return TRUE;
+}
+
+static void
+mixer_close(SugarAudioManager *manager)
+{
+	manager->priv->timer_id = g_timeout_add (4000, (GSourceFunc)mixer_close_real, manager);
+}
+
+void
+sugar_audio_manager_set_volume (SugarAudioManager *manager,
+				int                level)
+{
+	gint i, *volumes, volume;
+	GstMixerTrack *track;
+
+	if (mixer_open(manager) == FALSE)
+		return;
+
+	track = manager->priv->track;
+	volume = CLAMP(level, 0, 100);
+
+	/* Rescale the volume from [0, 100] to [track min, track max]. */
+	volume = (volume / 100.0) * (track->max_volume - track->min_volume) +
+		 track->min_volume;
+
+	volumes = g_new(gint, track->num_channels);
+	for (i = 0; i < track->num_channels; ++i)
+		volumes[i] = (gint)volume;
+	gst_mixer_set_volume(manager->priv->mixer, track, volumes);
+	g_free (volumes);
+ 	
+ 	mixer_close(manager);
+}
+
+static void
+sugar_audio_manager_finalize (GObject *object)
+{
+	SugarAudioManager *manager = SUGAR_AUDIO_MANAGER(object);
+
+	mixer_close_real(manager);
+
+	G_OBJECT_CLASS(sugar_audio_manager_parent_class)->finalize(object);
+}
+
+static void
+sugar_audio_manager_class_init(SugarAudioManagerClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS(klass);
+
+	gst_init (NULL, NULL);
+
+	object_class->finalize = sugar_audio_manager_finalize;
+
+	g_type_class_add_private(klass, sizeof(SugarAudioManagerPrivate));
+}
+
+static void
+sugar_audio_manager_init(SugarAudioManager *manager)
+{
+	manager->priv = SUGAR_AUDIO_MANAGER_GET_PRIVATE(manager);
+}
+
+