pipewire/src/modules/module-protocol-dbus.c

/* PipeWire
 *
 * Copyright © 2018 Wim Taymans
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <sys/socket.h>

#include <gio/gio.h>
#include <gio/gunixfdlist.h>

#include "config.h"

#include "pipewire/client/pipewire.h"
#include "pipewire/client/log.h"

#include "pipewire/server/core.h"
#include "pipewire/server/node.h"
#include "pipewire/server/module.h"
#include "pipewire/server/client-node.h"
#include "pipewire/server/client.h"
#include "pipewire/server/resource.h"
#include "pipewire/server/link.h"
#include "pipewire/server/factory.h"
#include "pipewire/server/data-loop.h"
#include "pipewire/server/main-loop.h"

#include "pipewire/dbus/org-pipewire.h"

#define PIPEWIRE_DBUS_SERVICE "org.pipewire"
#define PIPEWIRE_DBUS_OBJECT_PREFIX "/org/pipewire"
#define PIPEWIRE_DBUS_OBJECT_SERVER PIPEWIRE_DBUS_OBJECT_PREFIX "/server"
#define PIPEWIRE_DBUS_OBJECT_CLIENT PIPEWIRE_DBUS_OBJECT_PREFIX "/client"
#define PIPEWIRE_DBUS_OBJECT_NODE PIPEWIRE_DBUS_OBJECT_PREFIX "/node"
#define PIPEWIRE_DBUS_OBJECT_LINK PIPEWIRE_DBUS_OBJECT_PREFIX "/link"

struct impl {
	struct pw_core *core;
	struct spa_list link;

	struct pw_properties *properties;

	GDBusConnection *connection;
	GDBusObjectManagerServer *server_manager;

	struct spa_list client_list;
	struct spa_list object_list;

	struct pw_listener global_added;
	struct pw_listener global_removed;
};

struct object {
	struct impl *impl;
	struct spa_list link;
	struct pw_global *global;
	void *iface;
	PipeWireObjectSkeleton *skel;
	const gchar *object_path;
	pw_destroy_t destroy;
};

struct server {
	struct object parent;
	struct spa_list link;
	guint id;
};

struct client {
	struct object parent;
	struct spa_list link;
	gchar *sender;
	guint id;
};

struct node {
	struct object parent;
	struct pw_listener state_changed;
};

static void object_export(struct object *this)
{
	g_dbus_object_manager_server_export(this->impl->server_manager,
					    G_DBUS_OBJECT_SKELETON(this->skel));
	this->object_path = g_dbus_object_get_object_path(G_DBUS_OBJECT(this->skel));
	pw_log_debug("protocol-dbus %p: export object %s", this->impl, this->object_path);
}

static void object_unexport(struct object *this)
{
	if (this->object_path)
		g_dbus_object_manager_server_unexport(this->impl->server_manager,
						      this->object_path);
}

static void *object_new(size_t size,
			struct impl *impl,
			struct pw_global *global,
			void *iface,
			PipeWireObjectSkeleton * skel, bool export, pw_destroy_t destroy)
{
	struct object *this;

	this = calloc(1, size);
	this->impl = impl;
	this->global = global;
	this->iface = iface;
	this->skel = skel;
	this->destroy = destroy;

	spa_list_append(&impl->object_list, &this->link);

	if (export)
		object_export(this);

	return this;
}

static void object_destroy(struct object *this)
{
	spa_list_remove(&this->link);

	if (this->destroy)
		this->destroy(this);

	object_unexport(this);
	g_clear_object(&this->iface);
	g_clear_object(&this->skel);
	free(this);
}

static struct object *find_object(struct impl *impl, void *object)
{
	struct object *obj;
	spa_list_for_each(obj, &impl->object_list, link) {
		if (obj->global->object == object)
			return obj;
	}
	return NULL;
}

#if 0
struct _struct pw_properties {
	GHashTable *hashtable;
};

static void add_to_variant(const gchar * key, const gchar * value, GVariantBuilder * b)
{
	g_variant_builder_add(b, "{sv}", key, g_variant_new_string(value));
}
#endif

static void pw_properties_init_builder(struct pw_properties *properties, GVariantBuilder * builder)
{
	g_variant_builder_init(builder, G_VARIANT_TYPE("a{sv}"));
//  g_hash_table_foreach (properties->hashtable, (GHFunc) add_to_variant, builder);
}

static GVariant *pw_properties_to_variant(struct pw_properties *properties)
{
	GVariantBuilder builder;
	pw_properties_init_builder(properties, &builder);
	return g_variant_builder_end(&builder);
}

static struct pw_properties *pw_properties_from_variant(GVariant * variant)
{
	struct pw_properties *props;
	GVariantIter iter;
	//GVariant *value;
	//gchar *key;

	props = pw_properties_new(NULL, NULL);

	g_variant_iter_init(&iter, variant);
//  while (g_variant_iter_loop (&iter, "{sv}", &key, &value))
	//g_hash_table_replace (props->hashtable,
	//                      g_strdup (key),
	//                      g_variant_dup_string (value, NULL));

	return props;
}

static void
client_name_appeared_handler(GDBusConnection * connection,
			     const gchar * name, const gchar * name_owner, gpointer user_data)
{
	struct client *this = user_data;
	pw_log_debug("client %p: appeared %s %s", this, name, name_owner);
	object_export(&this->parent);
}

static void client_destroy(struct client *this)
{
	if (this->sender) {
		spa_list_remove(&this->link);
		free(this->sender);
		this->sender = NULL;
	}
}

static void
client_name_vanished_handler(GDBusConnection * connection, const gchar * name, gpointer user_data)
{
	struct client *this = user_data;
	pw_log_debug("client %p: vanished %s", this, name);
	g_bus_unwatch_name(this->id);
	/* destroying the client here will trigger the global_removed, which
	 * will then destroy our wrapper */
	pw_client_destroy(this->parent.global->object);
}


static struct client *client_new(struct impl *impl, const char *sender)
{
	struct client *this;
	struct pw_client *client;

	client = pw_client_new(impl->core, NULL, NULL, 0);

	if ((this = (struct client *) find_object(impl, client))) {
		pipewire_client1_set_sender(this->parent.iface, sender);

		this->sender = strdup(sender);
		this->id = g_bus_watch_name_on_connection(impl->connection,
							  this->sender,
							  G_BUS_NAME_WATCHER_FLAGS_NONE,
							  client_name_appeared_handler,
							  client_name_vanished_handler, this, NULL);

		spa_list_append(&impl->client_list, &this->link);
	}
	return this;
}

static struct pw_client *sender_get_client(struct impl *impl, const char *sender, bool create)
{
	struct client *client;

	spa_list_for_each(client, &impl->client_list, link) {
		if (strcmp(client->sender, sender) == 0)
			return client->parent.global->object;
	}
	if (!create)
		return NULL;

	client = client_new(impl, sender);

	return client->parent.global->object;
}

static bool
handle_create_node(PipeWireDaemon1 * interface,
		   GDBusMethodInvocation * invocation,
		   const char *arg_factory_name,
		   const char *arg_name, GVariant * arg_properties, gpointer user_data)
{
	struct impl *impl = user_data;
	struct pw_node_factory *factory;
	struct pw_node *node;
	struct pw_client *client;
	const char *sender, *object_path;
	struct pw_properties *props;
	struct object *object;

	sender = g_dbus_method_invocation_get_sender(invocation);
	client = sender_get_client(impl, sender, TRUE);

	pw_log_debug("protocol-dbus %p: create node: %s", impl, sender);

	props = pw_properties_from_variant(arg_properties);

	factory = pw_core_find_node_factory(impl->core, arg_factory_name);
	if (factory == NULL)
		goto no_factory;

	node = pw_node_factory_create_node(factory, client, arg_name, props);
	pw_properties_free(props);

	if (node == NULL)
		goto no_node;

	object = find_object(impl, node);
	if (object == NULL)
		goto object_failed;

	pw_resource_new(client,
			SPA_ID_INVALID,
			impl->core->type.node, node, (pw_destroy_t) pw_node_destroy);

	object_path = object->object_path;
	pw_log_debug("protocol-dbus %p: added node %p with path %s", impl, node, object_path);
	g_dbus_method_invocation_return_value(invocation, g_variant_new("(o)", object_path));
	return TRUE;

	/* ERRORS */
      no_factory:
	pw_log_debug("protocol-dbus %p: could not find factory named %s", impl,
		     arg_factory_name);
	g_dbus_method_invocation_return_dbus_error(invocation, "org.pipewire.Error",
						   "can't find factory");
	return TRUE;
      no_node:
	pw_log_debug("protocol-dbus %p: could not create node named %s from factory %s",
		     impl, arg_name, arg_factory_name);
	g_dbus_method_invocation_return_dbus_error(invocation, "org.pipewire.Error",
						   "can't create node");
	return TRUE;
      object_failed:
	pw_log_debug("protocol-dbus %p: could not create dbus object", impl);
	g_dbus_method_invocation_return_dbus_error(invocation,
						   "org.pipewire.Error",
						   "can't create object");
	return TRUE;
}

static void
on_node_state_changed(struct pw_listener *listener,
		      struct pw_node *node, enum pw_node_state old, enum pw_node_state state)
{
	struct node *object = SPA_CONTAINER_OF(listener, struct node, state_changed);

	pw_log_debug("protocol-dbus %p: node %p state change %s -> %s", object->parent.impl, node,
		     pw_node_state_as_string(old), pw_node_state_as_string(state));

	pipewire_node1_set_state(object->parent.iface, node->state);
}

static bool
handle_create_client_node(PipeWireDaemon1 * interface,
			  GDBusMethodInvocation * invocation,
			  const char *arg_name, GVariant * arg_properties, gpointer user_data)
{
	struct impl *impl = user_data;
	struct pw_client_node *node;
	struct pw_client *client;
	int res;
	const char *sender, *object_path, *target_node;
	struct pw_properties *props;
	GError *error = NULL;
	GUnixFDList *fdlist;
	int ctrl_fd, data_rfd, data_wfd;
	int ctrl_idx, data_ridx, data_widx;
	struct object *object;
	int fd[2];

	sender = g_dbus_method_invocation_get_sender(invocation);
	client = sender_get_client(impl, sender, TRUE);

	pw_log_debug("protocol-dbus %p: create client-node: %s", impl, sender);
	props = pw_properties_from_variant(arg_properties);

	target_node = pw_properties_get(props, PW_NODE_PROP_TARGET_NODE);
	if (target_node) {
		if (strncmp(target_node, "/org/pipewire/node_", strlen("/org/pipewire/node_")) == 0) {
			pw_properties_setf(props, PW_NODE_PROP_TARGET_NODE, "%s",
					   target_node + strlen("/org/pipewire/node_"));
		}
	}

	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 0, fd) != 0)
		goto no_socket_pair;

	ctrl_fd = fd[1];

	node = pw_client_node_new(client, SPA_ID_INVALID, arg_name, props);

	object = find_object(impl, node->node);
	if (object == NULL)
		goto object_failed;

	if ((res = pw_client_node_get_fds(node, &data_rfd, &data_wfd)) < 0)
		goto no_socket;

	object_path = object->object_path;
	pw_log_debug("protocol-dbus %p: add client-node %p, %s", impl, node, object_path);

	fdlist = g_unix_fd_list_new();
	ctrl_idx = g_unix_fd_list_append(fdlist, ctrl_fd, &error);
	data_ridx = g_unix_fd_list_append(fdlist, data_rfd, &error);
	data_widx = g_unix_fd_list_append(fdlist, data_wfd, &error);

	g_dbus_method_invocation_return_value_with_unix_fd_list(invocation,
								g_variant_new("(ohhh)", object_path,
									      ctrl_idx, data_ridx,
									      data_widx), fdlist);
	g_object_unref(fdlist);

	return TRUE;

      object_failed:
	pw_log_debug("protocol-dbus %p: could not create object", impl);
	goto exit_error;
      no_socket_pair:
	pw_log_debug("protocol-dbus %p: could not create socketpair: %s", impl,
		     strerror(errno));
	goto exit_error;
      no_socket:
	pw_log_debug("protocol-dbus %p: could not create socket: %s", impl,
		     strerror(errno));
	pw_client_node_destroy(node);
	goto exit_error;
      exit_error:
	g_dbus_method_invocation_return_gerror(invocation, error);
	g_clear_error(&error);
	return TRUE;
}

static void bus_acquired_handler(GDBusConnection * connection, const char *name, gpointer user_data)
{
	struct impl *impl = user_data;
	GDBusObjectManagerServer *manager = impl->server_manager;

	impl->connection = connection;
	g_dbus_object_manager_server_set_connection(manager, connection);
}

static void
name_acquired_handler(GDBusConnection * connection, const char *name, gpointer user_data)
{
}

static void name_lost_handler(GDBusConnection * connection, const char *name, gpointer user_data)
{
	struct impl *impl = user_data;
	GDBusObjectManagerServer *manager = impl->server_manager;

	g_dbus_object_manager_server_set_connection(manager, connection);
	impl->connection = connection;
}

static bool
handle_node_remove(PipeWireNode1 * interface,
		   GDBusMethodInvocation * invocation, gpointer user_data)
{
	struct pw_node *this = user_data;

	pw_log_debug("node %p: remove", this);

	g_dbus_method_invocation_return_value(invocation, g_variant_new("()"));
	return true;
}

static void
on_global_added(struct pw_listener *listener, struct pw_core *core, struct pw_global *global)
{
	struct impl *impl = SPA_CONTAINER_OF(listener, struct impl, global_added);
	PipeWireObjectSkeleton *skel;

	if (global->type == impl->core->type.client) {
		PipeWireClient1 *iface;
		struct pw_client *client = global->object;
		struct pw_properties *props = client->properties;
		char *path;

		asprintf(&path, "%s_%u", PIPEWIRE_DBUS_OBJECT_CLIENT, global->id);
		skel = pipewire_object_skeleton_new(path);
		free(path);

		iface = pipewire_client1_skeleton_new();
		pipewire_client1_set_properties(iface,
						props ? pw_properties_to_variant(props) : NULL);
		pipewire_object_skeleton_set_client1(skel, iface);

		object_new(sizeof(struct client),
			   impl, global, iface, skel, false, (pw_destroy_t) client_destroy);

	} else if (global->type == impl->core->type.node) {
		PipeWireNode1 *iface;
		struct pw_node *node = global->object;
		struct pw_properties *props = node->properties;
		char *path;
		struct node *obj;

		asprintf(&path, "%s_%u", PIPEWIRE_DBUS_OBJECT_NODE, global->id);
		skel = pipewire_object_skeleton_new(path);
		free(path);

		iface = pipewire_node1_skeleton_new();
		g_signal_connect(iface, "handle-remove", (GCallback) handle_node_remove, node);
		pipewire_node1_set_state(iface, node->state);
		pipewire_node1_set_owner(iface, "/");
		pipewire_node1_set_name(iface, node->name);
		pipewire_node1_set_properties(iface,
					      props ? pw_properties_to_variant(props) : NULL);
		pipewire_object_skeleton_set_node1(skel, iface);

		obj = object_new(sizeof(struct node), impl, global, iface, skel, true, NULL);
		pw_signal_add(&node->state_changed, &obj->state_changed, on_node_state_changed);
	} else if (global->object == impl) {
		struct impl *proto = global->object;
		struct server *server;
		PipeWireDaemon1 *iface;
		char *path;

		iface = pipewire_daemon1_skeleton_new();
		g_signal_connect(iface, "handle-create-node", (GCallback) handle_create_node,
				 proto);
		g_signal_connect(iface, "handle-create-client-node",
				 (GCallback) handle_create_client_node, proto);

		asprintf(&path, "%s_%u", PIPEWIRE_DBUS_OBJECT_SERVER, global->id);
		skel = pipewire_object_skeleton_new(path);
		free(path);

		pipewire_daemon1_set_user_name(iface, g_get_user_name());
		pipewire_daemon1_set_host_name(iface, g_get_host_name());
		pipewire_daemon1_set_version(iface, PACKAGE_VERSION);
		pipewire_daemon1_set_name(iface, PACKAGE_NAME);
		pipewire_daemon1_set_cookie(iface, g_random_int());
		pipewire_daemon1_set_properties(iface, proto->properties ?
						pw_properties_to_variant(proto->properties) : NULL);
		pipewire_object_skeleton_set_daemon1(skel, iface);

		server = object_new(sizeof(struct server), impl, global, iface, skel, true, NULL);
		server->id = g_bus_own_name(G_BUS_TYPE_SESSION,
					    PIPEWIRE_DBUS_SERVICE,
					    G_BUS_NAME_OWNER_FLAGS_REPLACE,
					    bus_acquired_handler,
					    name_acquired_handler, name_lost_handler, proto, NULL);
	} else if (global->type == impl->core->type.link) {
		PipeWireLink1 *iface;
		struct pw_link *link = global->object;
		struct object *obj;
		char *path;

		asprintf(&path, "%s_%u", PIPEWIRE_DBUS_OBJECT_LINK, global->id);
		skel = pipewire_object_skeleton_new(path);
		free(path);

		iface = pipewire_link1_skeleton_new();

		obj = link->output ? find_object(impl, link->output->node) : NULL;
		if (obj) {
			pipewire_link1_set_output_node(iface, obj->object_path);
			pipewire_link1_set_output_port(iface, link->output->port_id);
		} else {
			pipewire_link1_set_output_node(iface, "/");
			pipewire_link1_set_output_port(iface, SPA_ID_INVALID);
		}
		obj = link->input ? find_object(impl, link->input->node) : NULL;
		if (obj) {
			pipewire_link1_set_input_node(iface, obj->object_path);
			pipewire_link1_set_input_port(iface, link->input->port_id);
		} else {
			pipewire_link1_set_output_node(iface, "/");
			pipewire_link1_set_output_port(iface, SPA_ID_INVALID);
		}
		pipewire_object_skeleton_set_link1(skel, iface);

		object_new(sizeof(struct object), impl, global, iface, skel, true, NULL);
	}
}

static void
on_global_removed(struct pw_listener *listener, struct pw_core *core, struct pw_global *global)
{
	struct impl *impl = SPA_CONTAINER_OF(listener, struct impl, global_removed);
	struct object *object;

	if ((object = find_object(impl, global->object)))
		 object_destroy(object);
}

static struct impl *pw_protocol_dbus_new(struct pw_core *core, struct pw_properties *properties)
{
	struct impl *impl;

	impl = calloc(1, sizeof(struct impl));
	pw_log_debug("protocol-dbus %p: new", impl);

	impl->core = core;
	impl->properties = properties;

	spa_list_init(&impl->client_list);
	spa_list_init(&impl->object_list);

	pw_signal_add(&core->global_added, &impl->global_added, on_global_added);
	pw_signal_add(&core->global_removed, &impl->global_removed, on_global_removed);

	impl->server_manager = g_dbus_object_manager_server_new(PIPEWIRE_DBUS_OBJECT_PREFIX);

	return impl;
}

#if 0
static void pw_protocol_dbus_destroy(struct impl *impl)
{
	struct object *object, *tmp;

	pw_log_debug("protocol-dbus %p: destroy", impl);

	pw_global_destroy(impl->global);

	spa_list_for_each_safe(object, tmp, &impl->object_list, link)
	    object_destroy(object);

#if 0
	if (impl->id != 0)
		g_bus_unown_name(impl->id);
#endif

	pw_signal_remove(&impl->global_added);
	pw_signal_remove(&impl->global_removed);
	pw_signal_remove(&impl->node_state_changed);

	g_clear_object(&impl->server_manager);

	free(impl);
}
#endif

int pipewire__module_init(struct pw_module *module, const char *args)
{
	pw_protocol_dbus_new(module->core, NULL);
	return 0;
}