proxy-interfaces.c

/* WirePlumber
 *
 * Copyright © 2020 Collabora Ltd.
 *    @author George Kiagiadakis <george.kiagiadakis@collabora.com>
 *
 * SPDX-License-Identifier: MIT
 */

/**
 * SECTION: proxy-interfaces
 * @title: PipeWire Object Proxy Interfaces
 */

#define G_LOG_DOMAIN "wp-proxy-ifaces"

#include "proxy-interfaces.h"
#include "properties.h"

/**
 * WpPipewireObject:
 *
 * An interface for standard PipeWire objects. The common characteristic
 * of all objects that implement this interface is the presence of
 * an "info" structure that contains additional properties for this object
 * (in the form of a spa_dict / pw_properties) and optionally also
 * some parameters that can be enumerated and set on the object.
 */
G_DEFINE_INTERFACE (WpPipewireObject, wp_pipewire_object, WP_TYPE_PROXY)

static void
wp_pipewire_object_default_init (WpPipewireObjectInterface * iface)
{
  g_object_interface_install_property (iface,
      g_param_spec_pointer ("native-info", "native-info",
          "The native info structure",
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_interface_install_property (iface,
      g_param_spec_boxed ("properties", "properties",
          "The properties of the pipewire object", WP_TYPE_PROPERTIES,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_interface_install_property (iface,
      g_param_spec_variant ("param-info", "param-info",
          "The param info of the object", G_VARIANT_TYPE ("a{ss}"), NULL,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_signal_new ("params-changed", G_TYPE_FROM_INTERFACE (iface),
      G_SIGNAL_RUN_FIRST, 0, NULL, NULL, NULL, G_TYPE_NONE, 1, G_TYPE_STRING);
}

/**
 * wp_pipewire_object_get_native_info:
 * @self: the pipewire object
 *
 * Requires %WP_PIPEWIRE_OBJECT_FEATURE_INFO
 *
 * Returns: (nullable): the native pipewire info structure of this object
 *    (pw_node_info, pw_port_info, etc...)
 */
gconstpointer
wp_pipewire_object_get_native_info (WpPipewireObject * self)
{
  g_return_val_if_fail (WP_IS_PIPEWIRE_OBJECT (self), NULL);
  g_return_val_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->get_native_info,
      NULL);

  return WP_PIPEWIRE_OBJECT_GET_IFACE (self)->get_native_info (self);
}

/**
 * wp_pipewire_object_get_properties:
 * @self: the pipewire object
 *
 * Requires %WP_PIPEWIRE_OBJECT_FEATURE_INFO
 *
 * Returns: (transfer full): the pipewire properties of this object;
 *   normally these are the properties that are part of the info structure
 */
WpProperties *
wp_pipewire_object_get_properties (WpPipewireObject * self)
{
  g_return_val_if_fail (WP_IS_PIPEWIRE_OBJECT (self), NULL);
  g_return_val_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->get_properties,
      NULL);

  return WP_PIPEWIRE_OBJECT_GET_IFACE (self)->get_properties (self);
}

/**
 * wp_pipewire_object_iterate_properties:
 * @self: the pipewire object
 *
 * Requires %WP_PIPEWIRE_OBJECT_FEATURE_INFO
 *
 * Returns: (transfer full): an iterator that iterates over the pipewire
 *   properties of this object. Use wp_properties_iterator_item_get_key() and
 *   wp_properties_iterator_item_get_value() to parse the items returned by
 *   this iterator.
 */
WpIterator *
wp_pipewire_object_iterate_properties (WpPipewireObject * self)
{
  g_autoptr (WpProperties) properties =
      wp_pipewire_object_get_properties (self);
  return properties ? wp_properties_iterate (properties) : NULL;
}

/**
 * wp_pipewire_object_get_property:
 * @self: the pipewire object
 * @key: the property name
 *
 * Returns the value of a single pipewire property. This is the same as getting
 * the whole properties structure with wp_pipewire_object_get_properties() and
 * accessing a single property with wp_properties_get(), but saves one call
 * and having to clean up the #WpProperties reference count afterwards.
 *
 * The value is owned by the proxy, but it is guaranteed to stay alive
 * until execution returns back to the event loop.
 *
 * Requires %WP_PIPEWIRE_OBJECT_FEATURE_INFO
 *
 * Returns: (transfer none) (nullable): the value of the pipewire property @key
 *   or %NULL if the property doesn't exist
 */
const gchar *
wp_pipewire_object_get_property (WpPipewireObject * self, const gchar * key)
{
  g_autoptr (WpProperties) properties =
      wp_pipewire_object_get_properties (self);
  return properties ? wp_properties_get (properties, key) : NULL;
}

/**
 * wp_pipewire_object_get_param_info:
 * @self: the pipewire object
 *
 * Returns the available parameters of this pipewire object. The return value
 * is a variant of type `a{ss}`, where the key of each map entry is a spa param
 * type id (the same ids that you can pass in wp_pipewire_object_enum_params())
 * and the value is a string that can contain the following letters,
 * each of them representing a flag:
 *   - `r`: the param is readable (`SPA_PARAM_INFO_READ`)
 *   - `w`: the param is writable (`SPA_PARAM_INFO_WRITE`)
 *
 * For params that are readable, you can query them with
 * wp_pipewire_object_enum_params()
 *
 * Params that are writable can be set with wp_pipewire_object_set_param()
 *
 * Requires %WP_PIPEWIRE_OBJECT_FEATURE_INFO
 *
 * Returns: (transfer full) (nullable): a variant of type `a{ss}` or %NULL
 *   if the object does not support params at all
 */
GVariant *
wp_pipewire_object_get_param_info (WpPipewireObject * self)
{
  g_return_val_if_fail (WP_IS_PIPEWIRE_OBJECT (self), NULL);
  g_return_val_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->get_param_info,
      NULL);

  return WP_PIPEWIRE_OBJECT_GET_IFACE (self)->get_param_info (self);
}

/**
 * wp_pipewire_object_enum_params:
 * @self: the pipewire object
 * @id: (nullable): the parameter id to enumerate or %NULL for all parameters
 * @filter: (nullable): a param filter or %NULL
 * @cancellable: (nullable): a cancellable for the async operation
 * @callback: (scope async): a callback to call with the result
 * @user_data: (closure): data to pass to @callback
 *
 * Enumerate object parameters. This will asynchronously return the result,
 * or an error, by calling the given @callback. The result is going to
 * be a #WpIterator containing #WpSpaPod objects, which can be retrieved
 * with wp_pipewire_object_enum_params_finish().
 */
void
wp_pipewire_object_enum_params (WpPipewireObject * self, const gchar * id,
    WpSpaPod *filter, GCancellable * cancellable,
    GAsyncReadyCallback callback, gpointer user_data)
{
  g_return_if_fail (WP_IS_PIPEWIRE_OBJECT (self));
  g_return_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->enum_params);

  WP_PIPEWIRE_OBJECT_GET_IFACE (self)->enum_params (self, id, filter,
      cancellable, callback, user_data);
}

/**
 * wp_pipewire_object_enum_params_finish:
 * @self: the pipewire object
 * @res: the async result
 * @error: (out) (optional): the reported error of the operation, if any
 *
 * Returns: (transfer full) (nullable): an iterator to iterate over the
 *   collected params, or %NULL if the operation resulted in error;
 *   the items in the iterator are #WpSpaPod
 */
WpIterator *
wp_pipewire_object_enum_params_finish (WpPipewireObject * self,
    GAsyncResult * res, GError ** error)
{
  g_return_val_if_fail (WP_IS_PIPEWIRE_OBJECT (self), NULL);
  g_return_val_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->enum_params_finish,
      NULL);

  return WP_PIPEWIRE_OBJECT_GET_IFACE (self)->enum_params_finish (self, res,
      error);
}

/**
 * wp_pipewire_object_enum_cached_params
 * @self: the pipewire object
 * @id: the parameter id to enumerate
 *
 * This method can be used to retrieve object parameters in a synchronous way
 * (in contrast with wp_pipewire_object_enum_params(), which is async),
 * provided that the `WP_PIPEWIRE_OBJECT_FEATURE_PARAM_<something>` feature
 * that corresponds to the specified @id has been activated earlier.
 * These features enable monitoring and caching of params underneath, so that
 * they are always available for retrieval with this method.
 *
 * Note, however, that cached params may be out-of-date if they have changed
 * very recently on the remote object and the caching mechanism hasn't been
 * able to update them yet, so if you really need up-to-date information you
 * should only rely on wp_pipewire_object_enum_params() instead.
 *
 * Returns: (transfer full) (nullable): an iterator to iterate over cached
 *    parameters, or %NULL if paramteres for this @id are not cached;
 *    the items in the iterator are #WpSpaPod
 */
WpIterator *
wp_pipewire_object_enum_cached_params (WpPipewireObject * self,
    const gchar * id)
{
  g_return_val_if_fail (WP_IS_PIPEWIRE_OBJECT (self), NULL);
  g_return_val_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->enum_cached_params,
      NULL);

  return WP_PIPEWIRE_OBJECT_GET_IFACE (self)->enum_cached_params (self, id);
}

/**
 * wp_pipewire_object_set_param:
 * @self: the pipewire object
 * @id: the parameter id to set
 * @param: the parameter to set
 *
 * Sets a parameter on the object.
 */
void
wp_pipewire_object_set_param (WpPipewireObject * self, const gchar * id,
    WpSpaPod * param)
{
  g_return_if_fail (WP_IS_PIPEWIRE_OBJECT (self));
  g_return_if_fail (WP_PIPEWIRE_OBJECT_GET_IFACE (self)->set_param);

  WP_PIPEWIRE_OBJECT_GET_IFACE (self)->set_param (self, id, param);
}