gstreamer/ext/alsa/gstalsamixerelement.c
2011-12-22 16:37:29 +01:00

218 lines
6.3 KiB
C

/* ALSA mixer implementation.
* Copyright (C) 2003 Leif Johnson <leif@ambient.2y.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 "gstalsamixerelement.h"
#include "gstalsadeviceprobe.h"
#define DEFAULT_PROP_DEVICE "default"
#define DEFAULT_PROP_DEVICE_NAME ""
enum
{
PROP_0,
PROP_DEVICE,
PROP_DEVICE_NAME
};
static void gst_alsa_mixer_element_init_interfaces (GType type);
#define gst_alsa_mixer_element_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstAlsaMixerElement, gst_alsa_mixer_element,
GST_TYPE_ELEMENT,
gst_alsa_mixer_element_init_interfaces (g_define_type_id));
/* massive macro that takes care of all the GstMixer stuff */
GST_IMPLEMENT_ALSA_MIXER_METHODS (GstAlsaMixerElement, gst_alsa_mixer_element);
static void gst_alsa_mixer_element_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec);
static void gst_alsa_mixer_element_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec);
static void gst_alsa_mixer_element_finalize (GObject * object);
static GstStateChangeReturn gst_alsa_mixer_element_change_state (GstElement
* element, GstStateChange transition);
static void
gst_alsa_mixer_element_init_interfaces (GType type)
{
static const GInterfaceInfo mixer_iface_info = {
(GInterfaceInitFunc) gst_alsa_mixer_element_interface_init,
NULL,
NULL,
};
g_type_add_interface_static (type, GST_TYPE_MIXER, &mixer_iface_info);
#if 0
gst_alsa_type_add_device_property_probe_interface (type);
#endif
}
static void
gst_alsa_mixer_element_class_init (GstAlsaMixerElementClass * klass)
{
GstElementClass *element_class;
GObjectClass *gobject_class;
element_class = (GstElementClass *) klass;
gobject_class = (GObjectClass *) klass;
gobject_class->finalize = gst_alsa_mixer_element_finalize;
gobject_class->get_property = gst_alsa_mixer_element_get_property;
gobject_class->set_property = gst_alsa_mixer_element_set_property;
g_object_class_install_property (gobject_class, PROP_DEVICE,
g_param_spec_string ("device", "Device",
"ALSA device, as defined in an asound configuration file",
DEFAULT_PROP_DEVICE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_DEVICE_NAME,
g_param_spec_string ("device-name", "Device name",
"Human-readable name of the sound device",
DEFAULT_PROP_DEVICE_NAME, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
gst_element_class_set_details_simple (element_class,
"Alsa mixer", "Generic/Audio",
"Control sound input and output levels with ALSA",
"Leif Johnson <leif@ambient.2y.net>");
element_class->change_state =
GST_DEBUG_FUNCPTR (gst_alsa_mixer_element_change_state);
}
static void
gst_alsa_mixer_element_finalize (GObject * obj)
{
GstAlsaMixerElement *this = GST_ALSA_MIXER_ELEMENT (obj);
g_free (this->device);
G_OBJECT_CLASS (parent_class)->finalize (obj);
}
static void
gst_alsa_mixer_element_init (GstAlsaMixerElement * this)
{
this->mixer = NULL;
this->device = g_strdup (DEFAULT_PROP_DEVICE);
}
static void
gst_alsa_mixer_element_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstAlsaMixerElement *this = GST_ALSA_MIXER_ELEMENT (object);
switch (prop_id) {
case PROP_DEVICE:{
GST_OBJECT_LOCK (this);
g_free (this->device);
this->device = g_value_dup_string (value);
/* make sure we never set NULL, this is nice when we want to open the
* device. */
if (this->device == NULL)
this->device = g_strdup (DEFAULT_PROP_DEVICE);
GST_OBJECT_UNLOCK (this);
break;
}
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_alsa_mixer_element_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstAlsaMixerElement *this = GST_ALSA_MIXER_ELEMENT (object);
switch (prop_id) {
case PROP_DEVICE:{
GST_OBJECT_LOCK (this);
g_value_set_string (value, this->device);
GST_OBJECT_UNLOCK (this);
break;
}
case PROP_DEVICE_NAME:{
GST_OBJECT_LOCK (this);
if (this->mixer) {
g_value_set_string (value, this->mixer->cardname);
} else {
g_value_set_string (value, NULL);
}
GST_OBJECT_UNLOCK (this);
break;
}
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static GstStateChangeReturn
gst_alsa_mixer_element_change_state (GstElement * element,
GstStateChange transition)
{
GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
GstAlsaMixerElement *this = GST_ALSA_MIXER_ELEMENT (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
if (!this->mixer) {
this->mixer = gst_alsa_mixer_new (this->device, GST_ALSA_MIXER_ALL);
if (!this->mixer)
goto open_failed;
_gst_alsa_mixer_set_interface (this->mixer, GST_MIXER (element));
}
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret == GST_STATE_CHANGE_FAILURE)
return ret;
switch (transition) {
case GST_STATE_CHANGE_READY_TO_NULL:
if (this->mixer) {
gst_alsa_mixer_free (this->mixer);
this->mixer = NULL;
}
break;
default:
break;
}
return ret;
/* ERRORS */
open_failed:
{
GST_ELEMENT_ERROR (element, RESOURCE, OPEN_READ_WRITE, (NULL),
("Failed to open alsa mixer device '%s'", this->device));
return GST_STATE_CHANGE_FAILURE;
}
}