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_set_name (idle_source, "[gio] call_in_idle_cb");
 201   g_source_attach (idle_source, client->main_context);
 202   g_source_unref (idle_source);
 203 }
 204
 205 static void
 206 do_call (Client *client, CallType call_type)
 207 {
 208   GMainContext *current_context;
 209
 210   /* only schedule in idle if we're not in the right thread */
 211   current_context = g_main_context_ref_thread_default ();
 212   if (current_context != client->main_context)
 213     schedule_call_in_idle (client, call_type);
 214   else
 215     actually_do_call (client, client->connection, call_type);
 216   g_main_context_unref (current_context);
 217 }
 218
 219 static void
 220 call_acquired_handler (Client *client)
 221 {
 222   G_LOCK (lock);
 223   if (client->previous_call != PREVIOUS_CALL_ACQUIRED)
 224     {
 225       client->previous_call = PREVIOUS_CALL_ACQUIRED;
 226       if (!client->cancelled)
 227         {
 228           G_UNLOCK (lock);
 229           do_call (client, CALL_TYPE_NAME_ACQUIRED);
 230           goto out;
 231         }
 232     }
 233   G_UNLOCK (lock);
 234  out:
 235   ;
 236 }
 237
 238 static void
 239 call_lost_handler (Client  *client)
 240 {
 241   G_LOCK (lock);
 242   if (client->previous_call != PREVIOUS_CALL_LOST)
 243     {
 244       client->previous_call = PREVIOUS_CALL_LOST;
 245       if (!client->cancelled)
 246         {
 247           G_UNLOCK (lock);
 248           do_call (client, CALL_TYPE_NAME_LOST);
 249           goto out;
 250         }
 251     }
 252   G_UNLOCK (lock);
 253  out:
 254   ;
 255 }
 256
 257 /* ---------------------------------------------------------------------------------------------------- */
 258
 259 static void
 260 on_name_lost_or_acquired (GDBusConnection  *connection,
 261                           const gchar      *sender_name,
 262                           const gchar      *object_path,
 263                           const gchar      *interface_name,
 264                           const gchar      *signal_name,
 265                           GVariant         *parameters,
 266                           gpointer          user_data)
 267 {
 268   Client *client = user_data;
 269   const gchar *name;
 270
 271   if (g_strcmp0 (object_path, "/org/freedesktop/DBus") != 0 ||
 272       g_strcmp0 (interface_name, "org.freedesktop.DBus") != 0 ||
 273       g_strcmp0 (sender_name, "org.freedesktop.DBus") != 0)
 274     goto out;
 275
 276   if (g_strcmp0 (signal_name, "NameLost") == 0)
 277     {
 278       g_variant_get (parameters, "(&s)", &name);
 279       if (g_strcmp0 (name, client->name) == 0)
 280         {
 281           call_lost_handler (client);
 282         }
 283     }
 284   else if (g_strcmp0 (signal_name, "NameAcquired") == 0)
 285     {
 286       g_variant_get (parameters, "(&s)", &name);
 287       if (g_strcmp0 (name, client->name) == 0)
 288         {
 289           call_acquired_handler (client);
 290         }
 291     }
 292  out:
 293   ;
 294 }
 295
 296 /* ---------------------------------------------------------------------------------------------------- */
 297
 298 static void
 299 process_request_name_reply (Client  *client,
 300                             guint32  request_name_reply)
 301 {
 302   gboolean subscribe;
 303
 304   subscribe = FALSE;
 305
 306   switch (request_name_reply)
 307     {
 308     case 1: /* DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER */
 309       /* We got the name - now listen for NameLost and NameAcquired */
 310       call_acquired_handler (client);
 311       subscribe = TRUE;
 312       client->needs_release = TRUE;
 313       break;
 314
 315     case 2: /* DBUS_REQUEST_NAME_REPLY_IN_QUEUE */
 316       /* Waiting in line - listen for NameLost and NameAcquired */
 317       call_lost_handler (client);
 318       subscribe = TRUE;
 319       client->needs_release = TRUE;
 320       break;
 321
 322     default:
 323       /* assume we couldn't get the name - explicit fallthrough */
 324     case 3: /* DBUS_REQUEST_NAME_REPLY_EXISTS */
 325     case 4: /* DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER */
 326       /* Some other part of the process is already owning the name */
 327       call_lost_handler (client);
 328       break;
 329     }
 330
 331
 332   if (subscribe)
 333     {
 334       GDBusConnection *connection = NULL;
 335
 336       /* if cancelled, there is no point in subscribing to signals - if not, make sure
 337        * we use a known good Connection object since it may be set to NULL at any point
 338        * after being cancelled
 339        */
 340       G_LOCK (lock);
 341       if (!client->cancelled)
 342         connection = g_object_ref (client->connection);
 343       G_UNLOCK (lock);
 344
 345       /* start listening to NameLost and NameAcquired messages */
 346       if (connection != NULL)
 347         {
 348           client->name_lost_subscription_id =
 349             g_dbus_connection_signal_subscribe (connection,
 350                                                 "org.freedesktop.DBus",
 351                                                 "org.freedesktop.DBus",
 352                                                 "NameLost",
 353                                                 "/org/freedesktop/DBus",
 354                                                 client->name,
 355                                                 G_DBUS_SIGNAL_FLAGS_NONE,
 356                                                 on_name_lost_or_acquired,
 357                                                 client,
 358                                                 NULL);
 359           client->name_acquired_subscription_id =
 360             g_dbus_connection_signal_subscribe (connection,
 361                                                 "org.freedesktop.DBus",
 362                                                 "org.freedesktop.DBus",
 363                                                 "NameAcquired",
 364                                                 "/org/freedesktop/DBus",
 365                                                 client->name,
 366                                                 G_DBUS_SIGNAL_FLAGS_NONE,
 367                                                 on_name_lost_or_acquired,
 368                                                 client,
 369                                                 NULL);
 370           g_object_unref (connection);
 371         }
 372     }
 373 }
 374
 375 /* ---------------------------------------------------------------------------------------------------- */
 376
 377 static void
 378 on_connection_disconnected (GDBusConnection *connection,
 379                             gboolean         remote_peer_vanished,
 380                             GError          *error,
 381                             gpointer         user_data)
 382 {
 383   Client *client = user_data;
 384
 385   if (client->disconnected_signal_handler_id > 0)
 386     g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 387   if (client->name_acquired_subscription_id > 0)
 388     g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 389   if (client->name_lost_subscription_id > 0)
 390     g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 391   g_object_unref (client->connection);
 392   client->disconnected_signal_handler_id = 0;
 393   client->name_acquired_subscription_id = 0;
 394   client->name_lost_subscription_id = 0;
 395   client->connection = NULL;
 396
 397   call_lost_handler (client);
 398 }
 399
 400 /* ---------------------------------------------------------------------------------------------------- */
 401
 402 static void
 403 has_connection (Client *client)
 404 {
 405   GError *error = NULL;
 406   guint32 request_name_reply;
 407
 408   request_name_reply = 0;
 409
 410   /* listen for disconnection */
 411   client->disconnected_signal_handler_id = g_signal_connect (client->connection,
 412                                                              "closed",
 413                                                              G_CALLBACK (on_connection_disconnected),
 414                                                              client);
 415   /* attempt to acquire the name */
 416   request_name_reply = g_dbus_request_name (client->connection, client->name, client->flags, &error);
 417   g_assert_no_error (error);
 418
 419   process_request_name_reply (client, request_name_reply);
 420 }
 421
 422
 423 static void
 424 connection_get_cb (GObject      *source_object,
 425                    GAsyncResult *res,
 426                    gpointer      user_data)
 427 {
 428   Client *client = user_data;
 429
 430   /* must not do anything if already cancelled */
 431   G_LOCK (lock);
 432   if (client->cancelled)
 433     {
 434       G_UNLOCK (lock);
 435       goto out;
 436     }
 437   G_UNLOCK (lock);
 438
 439   client->connection = g_bus_get_finish (res, NULL);
 440   if (client->connection == NULL)
 441     {
 442       call_lost_handler (client);
 443       goto out;
 444     }
 445
 446   /* No need to schedule this in idle as we're already in the thread
 447    * that the user called g_bus_own_name() from. This is because
 448    * g_bus_get() guarantees that.
 449    *
 450    * Also, we need to ensure that the handler is invoked *before*
 451    * we call RequestName(). Otherwise there is a race.
 452    */
 453   if (client->bus_acquired_handler != NULL)
 454     {
 455       client->bus_acquired_handler (client->connection,
 456                                     client->name,
 457                                     client->user_data);
 458     }
 459
 460   has_connection (client);
 461
 462  out:
 463   client_unref (client);
 464 }
 465
 466 /* ---------------------------------------------------------------------------------------------------- */
 467
 468 /**
 469  * g_bus_own_name_on_connection:
 470  * @connection: a #GDBusConnection
 471  * @name: the well-known name to own
 472  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 473  * @name_acquired_handler: (allow-none): handler to invoke when @name is acquired or %NULL
 474  * @name_lost_handler: (allow-none): handler to invoke when @name is lost or %NULL
 475  * @user_data: user data to pass to handlers
 476  * @user_data_free_func: (allow-none): function for freeing @user_data or %NULL
 477  *
 478  * Like g_bus_own_name() but takes a #GDBusConnection instead of a
 479  * #GBusType.
 480  *
 481  * Returns: an identifier (never 0) that an be used with
 482  *     g_bus_unown_name() to stop owning the name
 483  *
 484  * Since: 2.26
 485  */
 486 guint
 487 g_bus_own_name_on_connection (GDBusConnection          *connection,
 488                               const gchar              *name,
 489                               GBusNameOwnerFlags        flags,
 490                               GBusNameAcquiredCallback  name_acquired_handler,
 491                               GBusNameLostCallback      name_lost_handler,
 492                               gpointer                  user_data,
 493                               GDestroyNotify            user_data_free_func)
 494 {
 495   Client *client;
 496
 497   g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
 498   g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_name (name), 0);
 499
 500   G_LOCK (lock);
 501
 502   client = g_new0 (Client, 1);
 503   client->ref_count = 1;
 504   client->id = next_global_id++; /* TODO: uh oh, handle overflow */
 505   client->name = g_strdup (name);
 506   client->flags = flags;
 507   client->name_acquired_handler = name_acquired_handler;
 508   client->name_lost_handler = name_lost_handler;
 509   client->user_data = user_data;
 510   client->user_data_free_func = user_data_free_func;
 511   client->main_context = g_main_context_ref_thread_default ();
 512
 513   client->connection = g_object_ref (connection);
 514
 515   if (map_id_to_client == NULL)
 516     {
 517       map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
 518     }
 519   g_hash_table_insert (map_id_to_client,
 520                        GUINT_TO_POINTER (client->id),
 521                        client);
 522
 523   G_UNLOCK (lock);
 524
 525   has_connection (client);
 526
 527   return client->id;
 528 }
 529
 530 /**
 531  * g_bus_own_name:
 532  * @bus_type: the type of bus to own a name on
 533  * @name: the well-known name to own
 534  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 535  * @bus_acquired_handler: (allow-none): handler to invoke when connected to the bus of type @bus_type or %NULL
 536  * @name_acquired_handler: (allow-none): handler to invoke when @name is acquired or %NULL
 537  * @name_lost_handler: (allow-none): handler to invoke when @name is lost or %NULL
 538  * @user_data: user data to pass to handlers
 539  * @user_data_free_func: (allow-none): function for freeing @user_data or %NULL
 540  *
 541  * Starts acquiring @name on the bus specified by @bus_type and calls
 542  * @name_acquired_handler and @name_lost_handler when the name is
 543  * acquired respectively lost. Callbacks will be invoked in the
 544  * [thread-default main context][g-main-context-push-thread-default]
 545  * of the thread you are calling this function from.
 546  *
 547  * You are guaranteed that one of the @name_acquired_handler and @name_lost_handler
 548  * callbacks will be invoked after calling this function - there are three
 549  * possible cases:
 550  *
 551  * - @name_lost_handler with a %NULL connection (if a connection to the bus
 552  *   can't be made).
 553  *
 554  * - @bus_acquired_handler then @name_lost_handler (if the name can't be
 555  *   obtained)
 556  *
 557  * - @bus_acquired_handler then @name_acquired_handler (if the name was
 558  *   obtained).
 559  *
 560  * When you are done owning the name, just call g_bus_unown_name()
 561  * with the owner id this function returns.
 562  *
 563  * If the name is acquired or lost (for example another application
 564  * could acquire the name if you allow replacement or the application
 565  * currently owning the name exits), the handlers are also invoked.
 566  * If the #GDBusConnection that is used for attempting to own the name
 567  * closes, then @name_lost_handler is invoked since it is no longer
 568  * possible for other processes to access the process.
 569  *
 570  * You cannot use g_bus_own_name() several times for the same name (unless
 571  * interleaved with calls to g_bus_unown_name()) - only the first call
 572  * will work.
 573  *
 574  * Another guarantee is that invocations of @name_acquired_handler
 575  * and @name_lost_handler are guaranteed to alternate; that
 576  * is, if @name_acquired_handler is invoked then you are
 577  * guaranteed that the next time one of the handlers is invoked, it
 578  * will be @name_lost_handler. The reverse is also true.
 579  *
 580  * If you plan on exporting objects (using e.g.
 581  * g_dbus_connection_register_object()), note that it is generally too late
 582  * to export the objects in @name_acquired_handler. Instead, you can do this
 583  * in @bus_acquired_handler since you are guaranteed that this will run
 584  * before @name is requested from the bus.
 585  *
 586  * This behavior makes it very simple to write applications that wants
 587  * to [own names][gdbus-owning-names] and export objects.
 588  * Simply register objects to be exported in @bus_acquired_handler and
 589  * unregister the objects (if any) in @name_lost_handler.
 590  *
 591  * Returns: an identifier (never 0) that an be used with
 592  *     g_bus_unown_name() to stop owning the name.
 593  *
 594  * Since: 2.26
 595  */
 596 guint
 597 g_bus_own_name (GBusType                  bus_type,
 598                 const gchar              *name,
 599                 GBusNameOwnerFlags        flags,
 600                 GBusAcquiredCallback      bus_acquired_handler,
 601                 GBusNameAcquiredCallback  name_acquired_handler,
 602                 GBusNameLostCallback      name_lost_handler,
 603                 gpointer                  user_data,
 604                 GDestroyNotify            user_data_free_func)
 605 {
 606   Client *client;
 607
 608   g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_name (name), 0);
 609
 610   G_LOCK (lock);
 611
 612   client = g_new0 (Client, 1);
 613   client->ref_count = 1;
 614   client->id = next_global_id++; /* TODO: uh oh, handle overflow */
 615   client->name = g_strdup (name);
 616   client->flags = flags;
 617   client->bus_acquired_handler = bus_acquired_handler;
 618   client->name_acquired_handler = name_acquired_handler;
 619   client->name_lost_handler = name_lost_handler;
 620   client->user_data = user_data;
 621   client->user_data_free_func = user_data_free_func;
 622   client->main_context = g_main_context_ref_thread_default ();
 623
 624   if (map_id_to_client == NULL)
 625     {
 626       map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
 627     }
 628   g_hash_table_insert (map_id_to_client,
 629                        GUINT_TO_POINTER (client->id),
 630                        client);
 631
 632   g_bus_get (bus_type,
 633              NULL,
 634              connection_get_cb,
 635              client_ref (client));
 636
 637   G_UNLOCK (lock);
 638
 639   return client->id;
 640 }
 641
 642 typedef struct {
 643   GClosure *bus_acquired_closure;
 644   GClosure *name_acquired_closure;
 645   GClosure *name_lost_closure;
 646 } OwnNameData;
 647
 648 static OwnNameData *
 649 own_name_data_new (GClosure *bus_acquired_closure,
 650                    GClosure *name_acquired_closure,
 651                    GClosure *name_lost_closure)
 652 {
 653   OwnNameData *data;
 654
 655   data = g_new0 (OwnNameData, 1);
 656
 657   if (bus_acquired_closure != NULL)
 658     {
 659       data->bus_acquired_closure = g_closure_ref (bus_acquired_closure);
 660       g_closure_sink (bus_acquired_closure);
 661       if (G_CLOSURE_NEEDS_MARSHAL (bus_acquired_closure))
 662         g_closure_set_marshal (bus_acquired_closure, g_cclosure_marshal_generic);
 663     }
 664
 665   if (name_acquired_closure != NULL)
 666     {
 667       data->name_acquired_closure = g_closure_ref (name_acquired_closure);
 668       g_closure_sink (name_acquired_closure);
 669       if (G_CLOSURE_NEEDS_MARSHAL (name_acquired_closure))
 670         g_closure_set_marshal (name_acquired_closure, g_cclosure_marshal_generic);
 671     }
 672
 673   if (name_lost_closure != NULL)
 674     {
 675       data->name_lost_closure = g_closure_ref (name_lost_closure);
 676       g_closure_sink (name_lost_closure);
 677       if (G_CLOSURE_NEEDS_MARSHAL (name_lost_closure))
 678         g_closure_set_marshal (name_lost_closure, g_cclosure_marshal_generic);
 679     }
 680
 681   return data;
 682 }
 683
 684 static void
 685 own_with_closures_on_bus_acquired (GDBusConnection *connection,
 686                                    const gchar     *name,
 687                                    gpointer         user_data)
 688 {
 689   OwnNameData *data = user_data;
 690   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 691
 692   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 693   g_value_set_object (&params[0], connection);
 694
 695   g_value_init (&params[1], G_TYPE_STRING);
 696   g_value_set_string (&params[1], name);
 697
 698   g_closure_invoke (data->bus_acquired_closure, NULL, 2, params, NULL);
 699
 700   g_value_unset (params + 0);
 701   g_value_unset (params + 1);
 702 }
 703
 704 static void
 705 own_with_closures_on_name_acquired (GDBusConnection *connection,
 706                                     const gchar     *name,
 707                                     gpointer         user_data)
 708 {
 709   OwnNameData *data = user_data;
 710   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 711
 712   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 713   g_value_set_object (&params[0], connection);
 714
 715   g_value_init (&params[1], G_TYPE_STRING);
 716   g_value_set_string (&params[1], name);
 717
 718   g_closure_invoke (data->name_acquired_closure, NULL, 2, params, NULL);
 719
 720   g_value_unset (params + 0);
 721   g_value_unset (params + 1);
 722 }
 723
 724 static void
 725 own_with_closures_on_name_lost (GDBusConnection *connection,
 726                                 const gchar     *name,
 727                                 gpointer         user_data)
 728 {
 729   OwnNameData *data = user_data;
 730   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 731
 732   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 733   g_value_set_object (&params[0], connection);
 734
 735   g_value_init (&params[1], G_TYPE_STRING);
 736   g_value_set_string (&params[1], name);
 737
 738   g_closure_invoke (data->name_lost_closure, NULL, 2, params, NULL);
 739
 740   g_value_unset (params + 0);
 741   g_value_unset (params + 1);
 742 }
 743
 744 static void
 745 bus_own_name_free_func (gpointer user_data)
 746 {
 747   OwnNameData *data = user_data;
 748
 749   if (data->bus_acquired_closure != NULL)
 750     g_closure_unref (data->bus_acquired_closure);
 751
 752   if (data->name_acquired_closure != NULL)
 753     g_closure_unref (data->name_acquired_closure);
 754
 755   if (data->name_lost_closure != NULL)
 756     g_closure_unref (data->name_lost_closure);
 757
 758   g_free (data);
 759 }
 760
 761 /**
 762  * g_bus_own_name_with_closures:
 763  * @bus_type: the type of bus to own a name on
 764  * @name: the well-known name to own
 765  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 766  * @bus_acquired_closure: (allow-none): #GClosure to invoke when connected to
 767  *     the bus of type @bus_type or %NULL
 768  * @name_acquired_closure: (allow-none): #GClosure to invoke when @name is
 769  *     acquired or %NULL
 770  * @name_lost_closure: (allow-none): #GClosure to invoke when @name is lost or
 771  *     %NULL
 772  *
 773  * Version of g_bus_own_name() using closures instead of callbacks for
 774  * easier binding in other languages.
 775  *
 776  * Returns: an identifier (never 0) that an be used with
 777  *     g_bus_unown_name() to stop owning the name.
 778  *
 779  * Rename to: g_bus_own_name
 780  *
 781  * Since: 2.26
 782  */
 783 guint
 784 g_bus_own_name_with_closures (GBusType            bus_type,
 785                               const gchar        *name,
 786                               GBusNameOwnerFlags  flags,
 787                               GClosure           *bus_acquired_closure,
 788                               GClosure           *name_acquired_closure,
 789                               GClosure           *name_lost_closure)
 790 {
 791   return g_bus_own_name (bus_type,
 792           name,
 793           flags,
 794           bus_acquired_closure != NULL ? own_with_closures_on_bus_acquired : NULL,
 795           name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
 796           name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
 797           own_name_data_new (bus_acquired_closure,
 798                              name_acquired_closure,
 799                              name_lost_closure),
 800           bus_own_name_free_func);
 801 }
 802
 803 /**
 804  * g_bus_own_name_on_connection_with_closures:
 805  * @connection: a #GDBusConnection
 806  * @name: the well-known name to own
 807  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 808  * @name_acquired_closure: (allow-none): #GClosure to invoke when @name is
 809  *     acquired or %NULL
 810  * @name_lost_closure: (allow-none): #GClosure to invoke when @name is lost
 811  *     or %NULL
 812  *
 813  * Version of g_bus_own_name_on_connection() using closures instead of
 814  * callbacks for easier binding in other languages.
 815  *
 816  * Returns: an identifier (never 0) that an be used with
 817  *     g_bus_unown_name() to stop owning the name.
 818  *
 819  * Rename to: g_bus_own_name_on_connection
 820  *
 821  * Since: 2.26
 822  */
 823 guint
 824 g_bus_own_name_on_connection_with_closures (GDBusConnection    *connection,
 825                                             const gchar        *name,
 826                                             GBusNameOwnerFlags  flags,
 827                                             GClosure           *name_acquired_closure,
 828                                             GClosure           *name_lost_closure)
 829 {
 830   return g_bus_own_name_on_connection (connection,
 831           name,
 832           flags,
 833           name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
 834           name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
 835           own_name_data_new (NULL,
 836                              name_acquired_closure,
 837                              name_lost_closure),
 838           bus_own_name_free_func);
 839 }
 840
 841 /**
 842  * g_bus_unown_name:
 843  * @owner_id: an identifier obtained from g_bus_own_name()
 844  *
 845  * Stops owning a name.
 846  *
 847  * Since: 2.26
 848  */
 849 void
 850 g_bus_unown_name (guint owner_id)
 851 {
 852   Client *client;
 853
 854   g_return_if_fail (owner_id > 0);
 855
 856   client = NULL;
 857
 858   G_LOCK (lock);
 859   if (owner_id == 0 || map_id_to_client == NULL ||
 860       (client = g_hash_table_lookup (map_id_to_client, GUINT_TO_POINTER (owner_id))) == NULL)
 861     {
 862       g_warning ("Invalid id %d passed to g_bus_unown_name()", owner_id);
 863       goto out;
 864     }
 865
 866   client->cancelled = TRUE;
 867   g_warn_if_fail (g_hash_table_remove (map_id_to_client, GUINT_TO_POINTER (owner_id)));
 868
 869  out:
 870   G_UNLOCK (lock);
 871
 872   /* do callback without holding lock */
 873   if (client != NULL)
 874     {
 875       /* Release the name if needed */
 876       if (client->needs_release &&
 877           client->connection != NULL &&
 878           !g_dbus_connection_is_closed (client->connection))
 879         {
 880           guint32 release_name_reply;
 881           GError *error;
 882
 883           error = NULL;
 884
 885           /* TODO: it kinda sucks having to do a sync call to release the name - but if
 886            * we don't, then a subsequent grab of the name will make the bus daemon return
 887            * IN_QUEUE which will trigger name_lost().
 888            *
 889            * I believe this is a bug in the bus daemon.
 890            */
 891
 892           release_name_reply = g_dbus_release_name (client->connection, client->name, &error);
 893           if (release_name_reply == G_BUS_RELEASE_NAME_FLAGS_ERROR)
 894             {
 895               g_warning ("Error releasing name %s: %s", client->name, error->message);
 896               g_error_free (error);
 897             }
 898           else
 899             if (release_name_reply != G_BUS_RELEASE_NAME_FLAGS_RELEASED)
 900               g_warning ("Unexpected reply %d when releasing name %s", release_name_reply, client->name);
 901         }
 902
 903       if (client->disconnected_signal_handler_id > 0)
 904         g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 905       if (client->name_acquired_subscription_id > 0)
 906         g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 907       if (client->name_lost_subscription_id > 0)
 908         g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 909       client->disconnected_signal_handler_id = 0;
 910       client->name_acquired_subscription_id = 0;
 911       client->name_lost_subscription_id = 0;
 912       if (client->connection != NULL)
 913         {
 914           g_object_unref (client->connection);
 915           client->connection = NULL;
 916         }
 917
 918       client_unref (client);
 919     }
 920 }