Spa Device

struct WpSpaDevice

A WpSpaDevice allows running a spa_device object locally, loading the implementation from a SPA factory. This is useful to run device monitors inside the session manager and have control over creating the actual nodes that the spa_device requests to create.

To enable the spa device, call wp_object_activate() requesting WP_SPA_DEVICE_FEATURE_ENABLED.

For actual devices (not device monitors) it also possible and desirable to export the device to PipeWire, which can be done by requesting WP_PROXY_FEATURE_BOUND from wp_object_activate(). When exporting, the export should be done before enabling the device, by requesting both features at the same time.

GObject Properties

properties

Properties of the spa device

WpProperties *

G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY

spa-device-handle

The spa device handle

gpointer

G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY

GObject Signals

create-object

void
create_object_callback (WpSpaDevice * self,
                        guint id,
                        gchar * type,
                        gchar * factory,
                        WpProperties * properties,
                        gpointer user_data)

This signal is emitted when the device is creating a managed object The handler is expected to actually construct the object using the requested SPA factory and with the given properties. The handler should then store the object with wp_spa_device_store_managed_object. The WpSpaDevice will later unref the reference stored by this function when the managed object is to be destroyed.

Parameters:

id - the id of the managed object
type - the SPA type that the managed object should have
factory - the name of the SPA factory to use to construct the managed object
properties - additional properties that the managed object should have

Flags: G_SIGNAL_RUN_FIRST

object-removed

void
object_removed_callback (WpSpaDevice * self,
                         guint id,
                         gpointer user_data)

This signal is emitted when the device has deleted a managed object. The handler may optionally release additional resources associated with this object.

It is not necessary to call wp_spa_device_store_managed_object() to remove the managed object, as this is done internally after this signal is fired.

Parameters:

id - the id of the managed object

Flags: G_SIGNAL_RUN_FIRST

enum WpSpaDeviceFeatures

Flags to be used as WpObjectFeatures for WpSpaDevice.

Values:

enumerator WP_SPA_DEVICE_FEATURE_ENABLED = (WP_PROXY_FEATURE_CUSTOM_START << 0): enables a spa device

WpSpaDevice *wp_spa_device_new_wrap(WpCore *core, gpointer spa_device_handle, WpProperties *properties)

Constructs an SPA Device object from an existing device handle.

Parameters

core – the wireplumber core
spa_device_handle – the spa device handle
properties – (nullable) (transfer full): additional properties of the device

Returns

(transfer full): A new WpSpaDevice

WpSpaDevice *wp_spa_device_new_from_spa_factory(WpCore *core, const gchar *factory_name, WpProperties *properties)

Constructs a SPA_TYPE_INTERFACE_Device by loading the given SPA factory_name.

To export this device to the PipeWire server, you need to call wp_object_activate() requesting WP_PROXY_FEATURE_BOUND and wait for the operation to complete.

Parameters

core – the wireplumber core
factory_name – the name of the SPA factory
properties – (nullable) (transfer full): properties to be passed to device constructor

Returns

(nullable) (transfer full): A new WpSpaDevice wrapping the device that was constructed by the factory, or NULL if the factory does not exist or was unable to construct the device

WpProperties *wp_spa_device_get_properties(WpSpaDevice *self)

Gets the properties of this device.

Parameters

self – the spa device

Returns

(transfer full): the device properties

GObject *wp_spa_device_get_managed_object(WpSpaDevice *self, guint id)

Gets one of the objects managed by this device.

Parameters

self – the spa device
id – the (device-internal) id of the object to get

Returns

(transfer full): the managed object associated with id

void wp_spa_device_store_managed_object(WpSpaDevice *self, guint id, GObject *object)

Stores or removes a managed object into/from a device.

Parameters

self – the spa device
id – the (device-internal) id of the object
object – (transfer full) (nullable): the object to store or NULL to remove the managed object associated with id

WP_TYPE_SPA_DEVICE (wp_spa_device_get_type ()): The WpSpaDevice GType.