src/java.desktop/unix/native/libpipewire/include/pipewire/proxy.h

/* PipeWire */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-License-Identifier: MIT */

#ifndef PIPEWIRE_PROXY_H
#define PIPEWIRE_PROXY_H

#ifdef __cplusplus
extern "C" {
#endif

#include <spa/utils/hook.h>

/** \page page_proxy Proxy
 *
 * \see \ref pw_proxy
 *
 * \section sec_page_proxy_overview Overview
 *
 * The proxy object is a client side representation of a resource
 * that lives on a remote PipeWire instance.
 *
 * It is used to communicate with the remote object.
 *
 * \section sec_page_proxy_core Core proxy
 *
 * A proxy for a remote core object can be obtained by making
 * a remote connection with \ref pw_context_connect.
 * See \ref pw_proxy
 *
 * Some methods on proxy object allow creation of more proxy objects or
 * create a binding between a local proxy and global resource.
 *
 * \section sec_page_proxy_create Create
 *
 * A client first creates a new proxy object with pw_proxy_new(). A
 * type must be provided for this object.
 *
 * The protocol of the context will usually install an interface to
 * translate method calls and events to the wire format.
 *
 * The creator of the proxy will usually also install an event
 * implementation of the particular object type.
 *
 * \section sec_page_proxy_bind Bind
 *
 * To actually use the proxy object, one needs to create a server
 * side resource for it. This can be done by, for example, binding
 * to a global object or by calling a method that creates and binds
 * to a new remote object. In all cases, the local id is passed to
 * the server and is used to create a resource with the same id.
 *
 * \section sec_page_proxy_methods Methods
 *
 * To call a method on the proxy use the interface methods. Calling
 * any interface method will result in a request to the server to
 * perform the requested action on the corresponding resource.
 *
 * \section sec_page_proxy_events Events
 *
 * Events send from the server to the proxy will be demarshalled by
 * the protocol and will then result in a call to the installed
 * implementation of the proxy.
 *
 * \section sec_page_proxy_destroy Destroy
 *
 * Use pw_proxy_destroy() to destroy the client side object. This
 * is usually done automatically when the server removes the resource
 * associated to the proxy.
 */

/** \defgroup pw_proxy Proxy
 *
 * \brief Represents an object on the client side.
 *
 * A pw_proxy acts as a client side proxy to an object existing in a remote
 * pipewire instance. The proxy is responsible for converting interface functions
 * invoked by the client to PipeWire messages. Events will call the handlers
 * set in listener.
 *
 * \see \ref page_proxy
 */

/**
 * \addtogroup pw_proxy
 * \{
 */
struct pw_proxy;

#include <pipewire/protocol.h>

/** Proxy events, use \ref pw_proxy_add_listener */
struct pw_proxy_events {
#define PW_VERSION_PROXY_EVENTS        1
        uint32_t version;

    /** The proxy is destroyed */
        void (*destroy) (void *data);

    /** a proxy is bound to a global id */
        void (*bound) (void *data, uint32_t global_id);

    /** a proxy is removed from the server. Use pw_proxy_destroy to
     * free the proxy. */
        void (*removed) (void *data);

    /** a reply to a sync method completed */
        void (*done) (void *data, int seq);

    /** an error occurred on the proxy */
        void (*error) (void *data, int seq, int res, const char *message);

        void (*bound_props) (void *data, uint32_t global_id, const struct spa_dict *props);
};

/* Make a new proxy object. The id can be used to bind to a remote object and
 * can be retrieved with \ref pw_proxy_get_id . */
struct pw_proxy *
pw_proxy_new(struct pw_proxy *factory,
         const char *type,        /* interface type */
         uint32_t version,        /* interface version */
         size_t user_data_size    /* size of user data */);

/** Add an event listener to proxy */
void pw_proxy_add_listener(struct pw_proxy *proxy,
               struct spa_hook *listener,
               const struct pw_proxy_events *events,
               void *data);

/** Add a listener for the events received from the remote object. The
  * events depend on the type of the remote object type. */
void pw_proxy_add_object_listener(struct pw_proxy *proxy,    /**< the proxy */
                 struct spa_hook *listener,    /**< listener */
                 const void *funcs,        /**< proxied functions */
                 void *data            /**< data passed to events */);

/** destroy a proxy */
void pw_proxy_destroy(struct pw_proxy *proxy);

void pw_proxy_ref(struct pw_proxy *proxy);
void pw_proxy_unref(struct pw_proxy *proxy);

/** Get the user_data. The size was given in \ref pw_proxy_new */
void *pw_proxy_get_user_data(struct pw_proxy *proxy);

/** Get the local id of the proxy */
uint32_t pw_proxy_get_id(struct pw_proxy *proxy);

/** Get the type and version of the proxy */
const char *pw_proxy_get_type(struct pw_proxy *proxy, uint32_t *version);

/** Get the protocol used for the proxy */
struct pw_protocol *pw_proxy_get_protocol(struct pw_proxy *proxy);

/** Generate an sync method for a proxy. This will generate a done event
 * with the same seq number of the reply. */
int pw_proxy_sync(struct pw_proxy *proxy, int seq);

/** Set the global id this proxy is bound to. This is usually used internally
 * and will also emit the bound event */
int pw_proxy_set_bound_id(struct pw_proxy *proxy, uint32_t global_id);
/** Get the global id bound to this proxy of SPA_ID_INVALID when not bound
 * to a global */
uint32_t pw_proxy_get_bound_id(struct pw_proxy *proxy);

/** Generate an error for a proxy */
int pw_proxy_error(struct pw_proxy *proxy, int res, const char *error);
int pw_proxy_errorf(struct pw_proxy *proxy, int res, const char *error, ...) SPA_PRINTF_FUNC(3, 4);

/** Get the listener of proxy */
struct spa_hook_list *pw_proxy_get_object_listeners(struct pw_proxy *proxy);

/** Get the marshal functions for the proxy */
const struct pw_protocol_marshal *pw_proxy_get_marshal(struct pw_proxy *proxy);

/** Install a marshal function on a proxy */
int pw_proxy_install_marshal(struct pw_proxy *proxy, bool implementor);

#define pw_proxy_notify(p,type,event,version,...)            \
    spa_hook_list_call(pw_proxy_get_object_listeners(p),        \
            type, event, version, ## __VA_ARGS__)

#define pw_proxy_call(p,type,method,version,...)            \
    spa_interface_call((struct spa_interface*)p,            \
            type, method, version, ##__VA_ARGS__)

#define pw_proxy_call_res(p,type,method,version,...)            \
({                                    \
    int _res = -ENOTSUP;                        \
    spa_interface_call_res((struct spa_interface*)p,        \
            type, _res, method, version, ##__VA_ARGS__);    \
    _res;                                \
})

/**
 * \}
 */

#ifdef __cplusplus
}
#endif

#endif /* PIPEWIRE_PROXY_H */