gio/gdbusnameowning.c

   1 /* GDBus - GLib D-Bus Library
   2  *
   3  * Copyright (C) 2008-2010 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Author: David Zeuthen <davidz@redhat.com>
  19  */
  20
  21 #include "config.h"
  22
  23 #include <stdlib.h>
  24
  25 #include "gdbusutils.h"
  26 #include "gdbusnameowning.h"
  27 #include "gdbuserror.h"
  28 #include "gdbusprivate.h"
  29 #include "gdbusconnection.h"
  30
  31 #include "glibintl.h"
  32
  33 /**
  34  * SECTION:gdbusnameowning
  35  * @title: Owning Bus Names
  36  * @short_description: Simple API for owning bus names
  37  * @include: gio/gio.h
  38  *
  39  * Convenience API for owning bus names.
  40  *
  41  * A simple example for owning a name can be found in
  42  * [gdbus-example-own-name.c](https://git.gnome.org/browse/glib/tree/gio/tests/gdbus-example-own-name.c)
  43  */
  44
  45 G_LOCK_DEFINE_STATIC (lock);
  46
  47 /* ---------------------------------------------------------------------------------------------------- */
  48
  49 typedef enum
  50 {
  51   PREVIOUS_CALL_NONE = 0,
  52   PREVIOUS_CALL_ACQUIRED,
  53   PREVIOUS_CALL_LOST,
  54 } PreviousCall;
  55
  56 typedef struct
  57 {
  58   volatile gint             ref_count;
  59   guint                     id;
  60   GBusNameOwnerFlags        flags;
  61   gchar                    *name;
  62   GBusAcquiredCallback      bus_acquired_handler;
  63   GBusNameAcquiredCallback  name_acquired_handler;
  64   GBusNameLostCallback      name_lost_handler;
  65   gpointer                  user_data;
  66   GDestroyNotify            user_data_free_func;
  67   GMainContext             *main_context;
  68
  69   PreviousCall              previous_call;
  70
  71   GDBusConnection          *connection;
  72   gulong                    disconnected_signal_handler_id;
  73   guint                     name_acquired_subscription_id;
  74   guint                     name_lost_subscription_id;
  75
  76   volatile gboolean         cancelled; /* must hold lock when reading or modifying */
  77
  78   gboolean                  needs_release;
  79 } Client;
  80
  81 static guint next_global_id = 1;
  82 static GHashTable *map_id_to_client = NULL;
  83
  84
  85 static Client *
  86 client_ref (Client *client)
  87 {
  88   g_atomic_int_inc (&client->ref_count);
  89   return client;
  90 }
  91
  92 static void
  93 client_unref (Client *client)
  94 {
  95   if (g_atomic_int_dec_and_test (&client->ref_count))
  96     {
  97       if (client->connection != NULL)
  98         {
  99           if (client->disconnected_signal_handler_id > 0)
 100             g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 101           if (client->name_acquired_subscription_id > 0)
 102             g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 103           if (client->name_lost_subscription_id > 0)
 104             g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 105           g_object_unref (client->connection);
 106         }
 107       g_main_context_unref (client->main_context);
 108       g_free (client->name);
 109       if (client->user_data_free_func != NULL)
 110         client->user_data_free_func (client->user_data);
 111       g_free (client);
 112     }
 113 }
 114
 115 /* ---------------------------------------------------------------------------------------------------- */
 116
 117
 118 typedef enum
 119 {
 120   CALL_TYPE_NAME_ACQUIRED,
 121   CALL_TYPE_NAME_LOST
 122 } CallType;
 123
 124 typedef struct
 125 {
 126   Client *client;
 127
 128   /* keep this separate because client->connection may
 129    * be set to NULL after scheduling the call
 130    */
 131   GDBusConnection *connection;
 132
 133   /* set to TRUE to call acquired */
 134   CallType call_type;
 135 } CallHandlerData;
 136
 137 static void
 138 call_handler_data_free (CallHandlerData *data)
 139 {
 140   if (data->connection != NULL)
 141     g_object_unref (data->connection);
 142   client_unref (data->client);
 143   g_free (data);
 144 }
 145
 146 static void
 147 actually_do_call (Client *client, GDBusConnection *connection, CallType call_type)
 148 {
 149   switch (call_type)
 150     {
 151     case CALL_TYPE_NAME_ACQUIRED:
 152       if (client->name_acquired_handler != NULL)
 153         {
 154           client->name_acquired_handler (connection,
 155                                          client->name,
 156                                          client->user_data);
 157         }
 158       break;
 159
 160     case CALL_TYPE_NAME_LOST:
 161       if (client->name_lost_handler != NULL)
 162         {
 163           client->name_lost_handler (connection,
 164                                      client->name,
 165                                      client->user_data);
 166         }
 167       break;
 168
 169     default:
 170       g_assert_not_reached ();
 171       break;
 172     }
 173 }
 174
 175 static gboolean
 176 call_in_idle_cb (gpointer _data)
 177 {
 178   CallHandlerData *data = _data;
 179   actually_do_call (data->client, data->connection, data->call_type);
 180   return FALSE;
 181 }
 182
 183 static void
 184 schedule_call_in_idle (Client *client, CallType  call_type)
 185 {
 186   CallHandlerData *data;
 187   GSource *idle_source;
 188
 189   data = g_new0 (CallHandlerData, 1);
 190   data->client = client_ref (client);
 191   data->connection = client->connection != NULL ? g_object_ref (client->connection) : NULL;
 192   data->call_type = call_type;
 193
 194   idle_source = g_idle_source_new ();
 195   g_source_set_priority (idle_source, G_PRIORITY_HIGH);
 196   g_source_set_callback (idle_source,
 197                          call_in_idle_cb,
 198                          data,
 199                          (GDestroyNotify) call_handler_data_free);
 200   g_source_attach (idle_source, client->main_context);
 201   g_source_unref (idle_source);
 202 }
 203
 204 static void
 205 do_call (Client *client, CallType call_type)
 206 {
 207   GMainContext *current_context;
 208
 209   /* only schedule in idle if we're not in the right thread */
 210   current_context = g_main_context_ref_thread_default ();
 211   if (current_context != client->main_context)
 212     schedule_call_in_idle (client, call_type);
 213   else
 214     actually_do_call (client, client->connection, call_type);
 215   g_main_context_unref (current_context);
 216 }
 217
 218 static void
 219 call_acquired_handler (Client *client)
 220 {
 221   G_LOCK (lock);
 222   if (client->previous_call != PREVIOUS_CALL_ACQUIRED)
 223     {
 224       client->previous_call = PREVIOUS_CALL_ACQUIRED;
 225       if (!client->cancelled)
 226         {
 227           G_UNLOCK (lock);
 228           do_call (client, CALL_TYPE_NAME_ACQUIRED);
 229           goto out;
 230         }
 231     }
 232   G_UNLOCK (lock);
 233  out:
 234   ;
 235 }
 236
 237 static void
 238 call_lost_handler (Client  *client)
 239 {
 240   G_LOCK (lock);
 241   if (client->previous_call != PREVIOUS_CALL_LOST)
 242     {
 243       client->previous_call = PREVIOUS_CALL_LOST;
 244       if (!client->cancelled)
 245         {
 246           G_UNLOCK (lock);
 247           do_call (client, CALL_TYPE_NAME_LOST);
 248           goto out;
 249         }
 250     }
 251   G_UNLOCK (lock);
 252  out:
 253   ;
 254 }
 255
 256 /* ---------------------------------------------------------------------------------------------------- */
 257
 258 static void
 259 on_name_lost_or_acquired (GDBusConnection  *connection,
 260                           const gchar      *sender_name,
 261                           const gchar      *object_path,
 262                           const gchar      *interface_name,
 263                           const gchar      *signal_name,
 264                           GVariant         *parameters,
 265                           gpointer          user_data)
 266 {
 267   Client *client = user_data;
 268   const gchar *name;
 269
 270   if (g_strcmp0 (object_path, "/org/freedesktop/DBus") != 0 ||
 271       g_strcmp0 (interface_name, "org.freedesktop.DBus") != 0 ||
 272       g_strcmp0 (sender_name, "org.freedesktop.DBus") != 0)
 273     goto out;
 274
 275   if (g_strcmp0 (signal_name, "NameLost") == 0)
 276     {
 277       g_variant_get (parameters, "(&s)", &name);
 278       if (g_strcmp0 (name, client->name) == 0)
 279         {
 280           call_lost_handler (client);
 281         }
 282     }
 283   else if (g_strcmp0 (signal_name, "NameAcquired") == 0)
 284     {
 285       g_variant_get (parameters, "(&s)", &name);
 286       if (g_strcmp0 (name, client->name) == 0)
 287         {
 288           call_acquired_handler (client);
 289         }
 290     }
 291  out:
 292   ;
 293 }
 294
 295 /* ---------------------------------------------------------------------------------------------------- */
 296
 297 static void
 298 request_name_cb (GObject      *source_object,
 299                  GAsyncResult *res,
 300                  gpointer      user_data)
 301 {
 302   Client *client = user_data;
 303   GVariant *result;
 304   guint32 request_name_reply;
 305   gboolean subscribe;
 306
 307   request_name_reply = 0;
 308   result = NULL;
 309
 310   /* don't use client->connection - it may be NULL already */
 311   result = g_dbus_connection_call_finish (G_DBUS_CONNECTION (source_object),
 312                                           res,
 313                                           NULL);
 314   if (result != NULL)
 315     {
 316       g_variant_get (result, "(u)", &request_name_reply);
 317       g_variant_unref (result);
 318     }
 319
 320   subscribe = FALSE;
 321
 322   switch (request_name_reply)
 323     {
 324     case 1: /* DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER */
 325       /* We got the name - now listen for NameLost and NameAcquired */
 326       call_acquired_handler (client);
 327       subscribe = TRUE;
 328       client->needs_release = TRUE;
 329       break;
 330
 331     case 2: /* DBUS_REQUEST_NAME_REPLY_IN_QUEUE */
 332       /* Waiting in line - listen for NameLost and NameAcquired */
 333       call_lost_handler (client);
 334       subscribe = TRUE;
 335       client->needs_release = TRUE;
 336       break;
 337
 338     default:
 339       /* assume we couldn't get the name - explicit fallthrough */
 340     case 3: /* DBUS_REQUEST_NAME_REPLY_EXISTS */
 341     case 4: /* DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER */
 342       /* Some other part of the process is already owning the name */
 343       call_lost_handler (client);
 344       break;
 345     }
 346
 347
 348   if (subscribe)
 349     {
 350       GDBusConnection *connection = NULL;
 351
 352       /* if cancelled, there is no point in subscribing to signals - if not, make sure
 353        * we use a known good Connection object since it may be set to NULL at any point
 354        * after being cancelled
 355        */
 356       G_LOCK (lock);
 357       if (!client->cancelled)
 358         connection = g_object_ref (client->connection);
 359       G_UNLOCK (lock);
 360
 361       /* start listening to NameLost and NameAcquired messages */
 362       if (connection != NULL)
 363         {
 364           client->name_lost_subscription_id =
 365             g_dbus_connection_signal_subscribe (connection,
 366                                                 "org.freedesktop.DBus",
 367                                                 "org.freedesktop.DBus",
 368                                                 "NameLost",
 369                                                 "/org/freedesktop/DBus",
 370                                                 client->name,
 371                                                 G_DBUS_SIGNAL_FLAGS_NONE,
 372                                                 on_name_lost_or_acquired,
 373                                                 client,
 374                                                 NULL);
 375           client->name_acquired_subscription_id =
 376             g_dbus_connection_signal_subscribe (connection,
 377                                                 "org.freedesktop.DBus",
 378                                                 "org.freedesktop.DBus",
 379                                                 "NameAcquired",
 380                                                 "/org/freedesktop/DBus",
 381                                                 client->name,
 382                                                 G_DBUS_SIGNAL_FLAGS_NONE,
 383                                                 on_name_lost_or_acquired,
 384                                                 client,
 385                                                 NULL);
 386           g_object_unref (connection);
 387         }
 388     }
 389
 390   client_unref (client);
 391 }
 392
 393 /* ---------------------------------------------------------------------------------------------------- */
 394
 395 static void
 396 on_connection_disconnected (GDBusConnection *connection,
 397                             gboolean         remote_peer_vanished,
 398                             GError          *error,
 399                             gpointer         user_data)
 400 {
 401   Client *client = user_data;
 402
 403   if (client->disconnected_signal_handler_id > 0)
 404     g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 405   if (client->name_acquired_subscription_id > 0)
 406     g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 407   if (client->name_lost_subscription_id > 0)
 408     g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 409   g_object_unref (client->connection);
 410   client->disconnected_signal_handler_id = 0;
 411   client->name_acquired_subscription_id = 0;
 412   client->name_lost_subscription_id = 0;
 413   client->connection = NULL;
 414
 415   call_lost_handler (client);
 416 }
 417
 418 /* ---------------------------------------------------------------------------------------------------- */
 419
 420 static void
 421 has_connection (Client *client)
 422 {
 423   /* listen for disconnection */
 424   client->disconnected_signal_handler_id = g_signal_connect (client->connection,
 425                                                              "closed",
 426                                                              G_CALLBACK (on_connection_disconnected),
 427                                                              client);
 428
 429   /* attempt to acquire the name */
 430   g_dbus_connection_call (client->connection,
 431                           "org.freedesktop.DBus",  /* bus name */
 432                           "/org/freedesktop/DBus", /* object path */
 433                           "org.freedesktop.DBus",  /* interface name */
 434                           "RequestName",           /* method name */
 435                           g_variant_new ("(su)",
 436                                          client->name,
 437                                          client->flags),
 438                           G_VARIANT_TYPE ("(u)"),
 439                           G_DBUS_CALL_FLAGS_NONE,
 440                           -1,
 441                           NULL,
 442                           (GAsyncReadyCallback) request_name_cb,
 443                           client_ref (client));
 444 }
 445
 446
 447 static void
 448 connection_get_cb (GObject      *source_object,
 449                    GAsyncResult *res,
 450                    gpointer      user_data)
 451 {
 452   Client *client = user_data;
 453
 454   /* must not do anything if already cancelled */
 455   G_LOCK (lock);
 456   if (client->cancelled)
 457     {
 458       G_UNLOCK (lock);
 459       goto out;
 460     }
 461   G_UNLOCK (lock);
 462
 463   client->connection = g_bus_get_finish (res, NULL);
 464   if (client->connection == NULL)
 465     {
 466       call_lost_handler (client);
 467       goto out;
 468     }
 469
 470   /* No need to schedule this in idle as we're already in the thread
 471    * that the user called g_bus_own_name() from. This is because
 472    * g_bus_get() guarantees that.
 473    *
 474    * Also, we need to ensure that the handler is invoked *before*
 475    * we call RequestName(). Otherwise there is a race.
 476    */
 477   if (client->bus_acquired_handler != NULL)
 478     {
 479       client->bus_acquired_handler (client->connection,
 480                                     client->name,
 481                                     client->user_data);
 482     }
 483
 484   has_connection (client);
 485
 486  out:
 487   client_unref (client);
 488 }
 489
 490 /* ---------------------------------------------------------------------------------------------------- */
 491
 492 /**
 493  * g_bus_own_name_on_connection:
 494  * @connection: a #GDBusConnection
 495  * @name: the well-known name to own
 496  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 497  * @name_acquired_handler: (allow-none): handler to invoke when @name is acquired or %NULL
 498  * @name_lost_handler: (allow-none): handler to invoke when @name is lost or %NULL
 499  * @user_data: user data to pass to handlers
 500  * @user_data_free_func: (allow-none): function for freeing @user_data or %NULL
 501  *
 502  * Like g_bus_own_name() but takes a #GDBusConnection instead of a
 503  * #GBusType.
 504  *
 505  * Returns: an identifier (never 0) that an be used with
 506  *     g_bus_unown_name() to stop owning the name
 507  *
 508  * Since: 2.26
 509  */
 510 guint
 511 g_bus_own_name_on_connection (GDBusConnection          *connection,
 512                               const gchar              *name,
 513                               GBusNameOwnerFlags        flags,
 514                               GBusNameAcquiredCallback  name_acquired_handler,
 515                               GBusNameLostCallback      name_lost_handler,
 516                               gpointer                  user_data,
 517                               GDestroyNotify            user_data_free_func)
 518 {
 519   Client *client;
 520
 521   g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
 522   g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_name (name), 0);
 523
 524   G_LOCK (lock);
 525
 526   client = g_new0 (Client, 1);
 527   client->ref_count = 1;
 528   client->id = next_global_id++; /* TODO: uh oh, handle overflow */
 529   client->name = g_strdup (name);
 530   client->flags = flags;
 531   client->name_acquired_handler = name_acquired_handler;
 532   client->name_lost_handler = name_lost_handler;
 533   client->user_data = user_data;
 534   client->user_data_free_func = user_data_free_func;
 535   client->main_context = g_main_context_ref_thread_default ();
 536
 537   client->connection = g_object_ref (connection);
 538
 539   if (map_id_to_client == NULL)
 540     {
 541       map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
 542     }
 543   g_hash_table_insert (map_id_to_client,
 544                        GUINT_TO_POINTER (client->id),
 545                        client);
 546
 547   G_UNLOCK (lock);
 548
 549   has_connection (client);
 550
 551   return client->id;
 552 }
 553
 554 /**
 555  * g_bus_own_name:
 556  * @bus_type: the type of bus to own a name on
 557  * @name: the well-known name to own
 558  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 559  * @bus_acquired_handler: (allow-none): handler to invoke when connected to the bus of type @bus_type or %NULL
 560  * @name_acquired_handler: (allow-none): handler to invoke when @name is acquired or %NULL
 561  * @name_lost_handler: (allow-none): handler to invoke when @name is lost or %NULL
 562  * @user_data: user data to pass to handlers
 563  * @user_data_free_func: (allow-none): function for freeing @user_data or %NULL
 564  *
 565  * Starts acquiring @name on the bus specified by @bus_type and calls
 566  * @name_acquired_handler and @name_lost_handler when the name is
 567  * acquired respectively lost. Callbacks will be invoked in the
 568  * [thread-default main context][g-main-context-push-thread-default]
 569  * of the thread you are calling this function from.
 570  *
 571  * You are guaranteed that one of the @name_acquired_handler and @name_lost_handler
 572  * callbacks will be invoked after calling this function - there are three
 573  * possible cases:
 574  *
 575  * - @name_lost_handler with a %NULL connection (if a connection to the bus
 576  *   can't be made).
 577  *
 578  * - @bus_acquired_handler then @name_lost_handler (if the name can't be
 579  *   obtained)
 580  *
 581  * - @bus_acquired_handler then @name_acquired_handler (if the name was
 582  *   obtained).
 583  *
 584  * When you are done owning the name, just call g_bus_unown_name()
 585  * with the owner id this function returns.
 586  *
 587  * If the name is acquired or lost (for example another application
 588  * could acquire the name if you allow replacement or the application
 589  * currently owning the name exits), the handlers are also invoked.
 590  * If the #GDBusConnection that is used for attempting to own the name
 591  * closes, then @name_lost_handler is invoked since it is no longer
 592  * possible for other processes to access the process.
 593  *
 594  * You cannot use g_bus_own_name() several times for the same name (unless
 595  * interleaved with calls to g_bus_unown_name()) - only the first call
 596  * will work.
 597  *
 598  * Another guarantee is that invocations of @name_acquired_handler
 599  * and @name_lost_handler are guaranteed to alternate; that
 600  * is, if @name_acquired_handler is invoked then you are
 601  * guaranteed that the next time one of the handlers is invoked, it
 602  * will be @name_lost_handler. The reverse is also true.
 603  *
 604  * If you plan on exporting objects (using e.g.
 605  * g_dbus_connection_register_object()), note that it is generally too late
 606  * to export the objects in @name_acquired_handler. Instead, you can do this
 607  * in @bus_acquired_handler since you are guaranteed that this will run
 608  * before @name is requested from the bus.
 609  *
 610  * This behavior makes it very simple to write applications that wants
 611  * to [own names][gdbus-owning-names] and export objects.
 612  * Simply register objects to be exported in @bus_acquired_handler and
 613  * unregister the objects (if any) in @name_lost_handler.
 614  *
 615  * Returns: an identifier (never 0) that an be used with
 616  *     g_bus_unown_name() to stop owning the name.
 617  *
 618  * Since: 2.26
 619  */
 620 guint
 621 g_bus_own_name (GBusType                  bus_type,
 622                 const gchar              *name,
 623                 GBusNameOwnerFlags        flags,
 624                 GBusAcquiredCallback      bus_acquired_handler,
 625                 GBusNameAcquiredCallback  name_acquired_handler,
 626                 GBusNameLostCallback      name_lost_handler,
 627                 gpointer                  user_data,
 628                 GDestroyNotify            user_data_free_func)
 629 {
 630   Client *client;
 631
 632   g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_name (name), 0);
 633
 634   G_LOCK (lock);
 635
 636   client = g_new0 (Client, 1);
 637   client->ref_count = 1;
 638   client->id = next_global_id++; /* TODO: uh oh, handle overflow */
 639   client->name = g_strdup (name);
 640   client->flags = flags;
 641   client->bus_acquired_handler = bus_acquired_handler;
 642   client->name_acquired_handler = name_acquired_handler;
 643   client->name_lost_handler = name_lost_handler;
 644   client->user_data = user_data;
 645   client->user_data_free_func = user_data_free_func;
 646   client->main_context = g_main_context_ref_thread_default ();
 647
 648   if (map_id_to_client == NULL)
 649     {
 650       map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
 651     }
 652   g_hash_table_insert (map_id_to_client,
 653                        GUINT_TO_POINTER (client->id),
 654                        client);
 655
 656   g_bus_get (bus_type,
 657              NULL,
 658              connection_get_cb,
 659              client_ref (client));
 660
 661   G_UNLOCK (lock);
 662
 663   return client->id;
 664 }
 665
 666 typedef struct {
 667   GClosure *bus_acquired_closure;
 668   GClosure *name_acquired_closure;
 669   GClosure *name_lost_closure;
 670 } OwnNameData;
 671
 672 static OwnNameData *
 673 own_name_data_new (GClosure *bus_acquired_closure,
 674                    GClosure *name_acquired_closure,
 675                    GClosure *name_lost_closure)
 676 {
 677   OwnNameData *data;
 678
 679   data = g_new0 (OwnNameData, 1);
 680
 681   if (bus_acquired_closure != NULL)
 682     {
 683       data->bus_acquired_closure = g_closure_ref (bus_acquired_closure);
 684       g_closure_sink (bus_acquired_closure);
 685       if (G_CLOSURE_NEEDS_MARSHAL (bus_acquired_closure))
 686         g_closure_set_marshal (bus_acquired_closure, g_cclosure_marshal_generic);
 687     }
 688
 689   if (name_acquired_closure != NULL)
 690     {
 691       data->name_acquired_closure = g_closure_ref (name_acquired_closure);
 692       g_closure_sink (name_acquired_closure);
 693       if (G_CLOSURE_NEEDS_MARSHAL (name_acquired_closure))
 694         g_closure_set_marshal (name_acquired_closure, g_cclosure_marshal_generic);
 695     }
 696
 697   if (name_lost_closure != NULL)
 698     {
 699       data->name_lost_closure = g_closure_ref (name_lost_closure);
 700       g_closure_sink (name_lost_closure);
 701       if (G_CLOSURE_NEEDS_MARSHAL (name_lost_closure))
 702         g_closure_set_marshal (name_lost_closure, g_cclosure_marshal_generic);
 703     }
 704
 705   return data;
 706 }
 707
 708 static void
 709 own_with_closures_on_bus_acquired (GDBusConnection *connection,
 710                                    const gchar     *name,
 711                                    gpointer         user_data)
 712 {
 713   OwnNameData *data = user_data;
 714   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 715
 716   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 717   g_value_set_object (&params[0], connection);
 718
 719   g_value_init (&params[1], G_TYPE_STRING);
 720   g_value_set_string (&params[1], name);
 721
 722   g_closure_invoke (data->bus_acquired_closure, NULL, 2, params, NULL);
 723
 724   g_value_unset (params + 0);
 725   g_value_unset (params + 1);
 726 }
 727
 728 static void
 729 own_with_closures_on_name_acquired (GDBusConnection *connection,
 730                                     const gchar     *name,
 731                                     gpointer         user_data)
 732 {
 733   OwnNameData *data = user_data;
 734   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 735
 736   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 737   g_value_set_object (&params[0], connection);
 738
 739   g_value_init (&params[1], G_TYPE_STRING);
 740   g_value_set_string (&params[1], name);
 741
 742   g_closure_invoke (data->name_acquired_closure, NULL, 2, params, NULL);
 743
 744   g_value_unset (params + 0);
 745   g_value_unset (params + 1);
 746 }
 747
 748 static void
 749 own_with_closures_on_name_lost (GDBusConnection *connection,
 750                                 const gchar     *name,
 751                                 gpointer         user_data)
 752 {
 753   OwnNameData *data = user_data;
 754   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 755
 756   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 757   g_value_set_object (&params[0], connection);
 758
 759   g_value_init (&params[1], G_TYPE_STRING);
 760   g_value_set_string (&params[1], name);
 761
 762   g_closure_invoke (data->name_lost_closure, NULL, 2, params, NULL);
 763
 764   g_value_unset (params + 0);
 765   g_value_unset (params + 1);
 766 }
 767
 768 static void
 769 bus_own_name_free_func (gpointer user_data)
 770 {
 771   OwnNameData *data = user_data;
 772
 773   if (data->bus_acquired_closure != NULL)
 774     g_closure_unref (data->bus_acquired_closure);
 775
 776   if (data->name_acquired_closure != NULL)
 777     g_closure_unref (data->name_acquired_closure);
 778
 779   if (data->name_lost_closure != NULL)
 780     g_closure_unref (data->name_lost_closure);
 781
 782   g_free (data);
 783 }
 784
 785 /**
 786  * g_bus_own_name_with_closures:
 787  * @bus_type: the type of bus to own a name on
 788  * @name: the well-known name to own
 789  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 790  * @bus_acquired_closure: (allow-none): #GClosure to invoke when connected to
 791  *     the bus of type @bus_type or %NULL
 792  * @name_acquired_closure: (allow-none): #GClosure to invoke when @name is
 793  *     acquired or %NULL
 794  * @name_lost_closure: (allow-none): #GClosure to invoke when @name is lost or
 795  *     %NULL
 796  *
 797  * Version of g_bus_own_name() using closures instead of callbacks for
 798  * easier binding in other languages.
 799  *
 800  * Returns: an identifier (never 0) that an be used with
 801  *     g_bus_unown_name() to stop owning the name.
 802  *
 803  * Rename to: g_bus_own_name
 804  *
 805  * Since: 2.26
 806  */
 807 guint
 808 g_bus_own_name_with_closures (GBusType            bus_type,
 809                               const gchar        *name,
 810                               GBusNameOwnerFlags  flags,
 811                               GClosure           *bus_acquired_closure,
 812                               GClosure           *name_acquired_closure,
 813                               GClosure           *name_lost_closure)
 814 {
 815   return g_bus_own_name (bus_type,
 816           name,
 817           flags,
 818           bus_acquired_closure != NULL ? own_with_closures_on_bus_acquired : NULL,
 819           name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
 820           name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
 821           own_name_data_new (bus_acquired_closure,
 822                              name_acquired_closure,
 823                              name_lost_closure),
 824           bus_own_name_free_func);
 825 }
 826
 827 /**
 828  * g_bus_own_name_on_connection_with_closures:
 829  * @connection: a #GDBusConnection
 830  * @name: the well-known name to own
 831  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 832  * @name_acquired_closure: (allow-none): #GClosure to invoke when @name is
 833  *     acquired or %NULL
 834  * @name_lost_closure: (allow-none): #GClosure to invoke when @name is lost
 835  *     or %NULL
 836  *
 837  * Version of g_bus_own_name_on_connection() using closures instead of
 838  * callbacks for easier binding in other languages.
 839  *
 840  * Returns: an identifier (never 0) that an be used with
 841  *     g_bus_unown_name() to stop owning the name.
 842  *
 843  * Rename to: g_bus_own_name_on_connection
 844  *
 845  * Since: 2.26
 846  */
 847 guint
 848 g_bus_own_name_on_connection_with_closures (GDBusConnection    *connection,
 849                                             const gchar        *name,
 850                                             GBusNameOwnerFlags  flags,
 851                                             GClosure           *name_acquired_closure,
 852                                             GClosure           *name_lost_closure)
 853 {
 854   return g_bus_own_name_on_connection (connection,
 855           name,
 856           flags,
 857           name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
 858           name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
 859           own_name_data_new (NULL,
 860                              name_acquired_closure,
 861                              name_lost_closure),
 862           bus_own_name_free_func);
 863 }
 864
 865 /**
 866  * g_bus_unown_name:
 867  * @owner_id: an identifier obtained from g_bus_own_name()
 868  *
 869  * Stops owning a name.
 870  *
 871  * Since: 2.26
 872  */
 873 void
 874 g_bus_unown_name (guint owner_id)
 875 {
 876   Client *client;
 877
 878   g_return_if_fail (owner_id > 0);
 879
 880   client = NULL;
 881
 882   G_LOCK (lock);
 883   if (owner_id == 0 || map_id_to_client == NULL ||
 884       (client = g_hash_table_lookup (map_id_to_client, GUINT_TO_POINTER (owner_id))) == NULL)
 885     {
 886       g_warning ("Invalid id %d passed to g_bus_unown_name()", owner_id);
 887       goto out;
 888     }
 889
 890   client->cancelled = TRUE;
 891   g_warn_if_fail (g_hash_table_remove (map_id_to_client, GUINT_TO_POINTER (owner_id)));
 892
 893  out:
 894   G_UNLOCK (lock);
 895
 896   /* do callback without holding lock */
 897   if (client != NULL)
 898     {
 899       /* Release the name if needed */
 900       if (client->needs_release &&
 901           client->connection != NULL &&
 902           !g_dbus_connection_is_closed (client->connection))
 903         {
 904           GVariant *result;
 905           GError *error;
 906           guint32 release_name_reply;
 907
 908           /* TODO: it kinda sucks having to do a sync call to release the name - but if
 909            * we don't, then a subsequent grab of the name will make the bus daemon return
 910            * IN_QUEUE which will trigger name_lost().
 911            *
 912            * I believe this is a bug in the bus daemon.
 913            */
 914           error = NULL;
 915           result = g_dbus_connection_call_sync (client->connection,
 916                                                 "org.freedesktop.DBus",  /* bus name */
 917                                                 "/org/freedesktop/DBus", /* object path */
 918                                                 "org.freedesktop.DBus",  /* interface name */
 919                                                 "ReleaseName",           /* method name */
 920                                                 g_variant_new ("(s)", client->name),
 921                                                 G_VARIANT_TYPE ("(u)"),
 922                                                 G_DBUS_CALL_FLAGS_NONE,
 923                                                 -1,
 924                                                 NULL,
 925                                                 &error);
 926           if (result == NULL)
 927             {
 928               g_warning ("Error releasing name %s: %s", client->name, error->message);
 929               g_error_free (error);
 930             }
 931           else
 932             {
 933               g_variant_get (result, "(u)", &release_name_reply);
 934               if (release_name_reply != 1 /* DBUS_RELEASE_NAME_REPLY_RELEASED */)
 935                 {
 936                   g_warning ("Unexpected reply %d when releasing name %s", release_name_reply, client->name);
 937                 }
 938               g_variant_unref (result);
 939             }
 940         }
 941
 942       if (client->disconnected_signal_handler_id > 0)
 943         g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 944       if (client->name_acquired_subscription_id > 0)
 945         g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 946       if (client->name_lost_subscription_id > 0)
 947         g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 948       client->disconnected_signal_handler_id = 0;
 949       client->name_acquired_subscription_id = 0;
 950       client->name_lost_subscription_id = 0;
 951       if (client->connection != NULL)
 952         {
 953           g_object_unref (client->connection);
 954           client->connection = NULL;
 955         }
 956
 957       client_unref (client);
 958     }
 959 }