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 request_name_cb (GObject      *source_object,
 379                  GAsyncResult *res,
 380                  gpointer      user_data)
 381 {
 382   Client *client = user_data;
 383   GVariant *result;
 384   guint32 request_name_reply;
 385
 386   request_name_reply = 0;
 387   result = NULL;
 388
 389   /* don't use client->connection - it may be NULL already */
 390   result = g_dbus_connection_call_finish (G_DBUS_CONNECTION (source_object),
 391                                           res,
 392                                           NULL);
 393   if (result != NULL)
 394     {
 395       g_variant_get (result, "(u)", &request_name_reply);
 396       g_variant_unref (result);
 397     }
 398
 399   process_request_name_reply (client, request_name_reply);
 400
 401   client_unref (client);
 402 }
 403
 404 /* ---------------------------------------------------------------------------------------------------- */
 405
 406 static void
 407 on_connection_disconnected (GDBusConnection *connection,
 408                             gboolean         remote_peer_vanished,
 409                             GError          *error,
 410                             gpointer         user_data)
 411 {
 412   Client *client = user_data;
 413
 414   if (client->disconnected_signal_handler_id > 0)
 415     g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 416   if (client->name_acquired_subscription_id > 0)
 417     g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 418   if (client->name_lost_subscription_id > 0)
 419     g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 420   g_object_unref (client->connection);
 421   client->disconnected_signal_handler_id = 0;
 422   client->name_acquired_subscription_id = 0;
 423   client->name_lost_subscription_id = 0;
 424   client->connection = NULL;
 425
 426   call_lost_handler (client);
 427 }
 428
 429 /* ---------------------------------------------------------------------------------------------------- */
 430
 431 static void
 432 has_connection (Client *client)
 433 {
 434   /* listen for disconnection */
 435   client->disconnected_signal_handler_id = g_signal_connect (client->connection,
 436                                                              "closed",
 437                                                              G_CALLBACK (on_connection_disconnected),
 438                                                              client);
 439 #if 0
 440   /* attempt to acquire the name */
 441   if (G_IS_KDBUS_CONNECTION (g_dbus_connection_get_stream (client->connection)))
 442     {
 443       GVariant *result;
 444       guint32 request_name_reply;
 445
 446       request_name_reply = 0;
 447       result = NULL;
 448
 449       result = _g_kdbus_RequestName (client->connection, client->name, client->flags, NULL);
 450
 451       if (result != NULL)
 452         {
 453           g_variant_get (result, "(u)", &request_name_reply);
 454           g_variant_unref (result);
 455         }
 456
 457       process_request_name_reply (client, request_name_reply);
 458     }
 459   else
 460 #endif
 461     {
 462       g_dbus_connection_call (client->connection,
 463                               "org.freedesktop.DBus",  /* bus name */
 464                               "/org/freedesktop/DBus", /* object path */
 465                               "org.freedesktop.DBus",  /* interface name */
 466                               "RequestName",           /* method name */
 467                               g_variant_new ("(su)",
 468                                              client->name,
 469                                              client->flags),
 470                               G_VARIANT_TYPE ("(u)"),
 471                               G_DBUS_CALL_FLAGS_NONE,
 472                               -1,
 473                               NULL,
 474                               (GAsyncReadyCallback) request_name_cb,
 475                               client_ref (client));
 476     }
 477 }
 478
 479
 480 static void
 481 connection_get_cb (GObject      *source_object,
 482                    GAsyncResult *res,
 483                    gpointer      user_data)
 484 {
 485   Client *client = user_data;
 486
 487   /* must not do anything if already cancelled */
 488   G_LOCK (lock);
 489   if (client->cancelled)
 490     {
 491       G_UNLOCK (lock);
 492       goto out;
 493     }
 494   G_UNLOCK (lock);
 495
 496   client->connection = g_bus_get_finish (res, NULL);
 497   if (client->connection == NULL)
 498     {
 499       call_lost_handler (client);
 500       goto out;
 501     }
 502
 503   /* No need to schedule this in idle as we're already in the thread
 504    * that the user called g_bus_own_name() from. This is because
 505    * g_bus_get() guarantees that.
 506    *
 507    * Also, we need to ensure that the handler is invoked *before*
 508    * we call RequestName(). Otherwise there is a race.
 509    */
 510   if (client->bus_acquired_handler != NULL)
 511     {
 512       client->bus_acquired_handler (client->connection,
 513                                     client->name,
 514                                     client->user_data);
 515     }
 516
 517   has_connection (client);
 518
 519  out:
 520   client_unref (client);
 521 }
 522
 523 /* ---------------------------------------------------------------------------------------------------- */
 524
 525 /**
 526  * g_bus_own_name_on_connection:
 527  * @connection: a #GDBusConnection
 528  * @name: the well-known name to own
 529  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 530  * @name_acquired_handler: (allow-none): handler to invoke when @name is acquired or %NULL
 531  * @name_lost_handler: (allow-none): handler to invoke when @name is lost or %NULL
 532  * @user_data: user data to pass to handlers
 533  * @user_data_free_func: (allow-none): function for freeing @user_data or %NULL
 534  *
 535  * Like g_bus_own_name() but takes a #GDBusConnection instead of a
 536  * #GBusType.
 537  *
 538  * Returns: an identifier (never 0) that an be used with
 539  *     g_bus_unown_name() to stop owning the name
 540  *
 541  * Since: 2.26
 542  */
 543 guint
 544 g_bus_own_name_on_connection (GDBusConnection          *connection,
 545                               const gchar              *name,
 546                               GBusNameOwnerFlags        flags,
 547                               GBusNameAcquiredCallback  name_acquired_handler,
 548                               GBusNameLostCallback      name_lost_handler,
 549                               gpointer                  user_data,
 550                               GDestroyNotify            user_data_free_func)
 551 {
 552   Client *client;
 553
 554   g_return_val_if_fail (G_IS_DBUS_CONNECTION (connection), 0);
 555   g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_name (name), 0);
 556
 557   G_LOCK (lock);
 558
 559   client = g_new0 (Client, 1);
 560   client->ref_count = 1;
 561   client->id = next_global_id++; /* TODO: uh oh, handle overflow */
 562   client->name = g_strdup (name);
 563   client->flags = flags;
 564   client->name_acquired_handler = name_acquired_handler;
 565   client->name_lost_handler = name_lost_handler;
 566   client->user_data = user_data;
 567   client->user_data_free_func = user_data_free_func;
 568   client->main_context = g_main_context_ref_thread_default ();
 569
 570   client->connection = g_object_ref (connection);
 571
 572   if (map_id_to_client == NULL)
 573     {
 574       map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
 575     }
 576   g_hash_table_insert (map_id_to_client,
 577                        GUINT_TO_POINTER (client->id),
 578                        client);
 579
 580   G_UNLOCK (lock);
 581
 582   has_connection (client);
 583
 584   return client->id;
 585 }
 586
 587 /**
 588  * g_bus_own_name:
 589  * @bus_type: the type of bus to own a name on
 590  * @name: the well-known name to own
 591  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 592  * @bus_acquired_handler: (allow-none): handler to invoke when connected to the bus of type @bus_type or %NULL
 593  * @name_acquired_handler: (allow-none): handler to invoke when @name is acquired or %NULL
 594  * @name_lost_handler: (allow-none): handler to invoke when @name is lost or %NULL
 595  * @user_data: user data to pass to handlers
 596  * @user_data_free_func: (allow-none): function for freeing @user_data or %NULL
 597  *
 598  * Starts acquiring @name on the bus specified by @bus_type and calls
 599  * @name_acquired_handler and @name_lost_handler when the name is
 600  * acquired respectively lost. Callbacks will be invoked in the
 601  * [thread-default main context][g-main-context-push-thread-default]
 602  * of the thread you are calling this function from.
 603  *
 604  * You are guaranteed that one of the @name_acquired_handler and @name_lost_handler
 605  * callbacks will be invoked after calling this function - there are three
 606  * possible cases:
 607  *
 608  * - @name_lost_handler with a %NULL connection (if a connection to the bus
 609  *   can't be made).
 610  *
 611  * - @bus_acquired_handler then @name_lost_handler (if the name can't be
 612  *   obtained)
 613  *
 614  * - @bus_acquired_handler then @name_acquired_handler (if the name was
 615  *   obtained).
 616  *
 617  * When you are done owning the name, just call g_bus_unown_name()
 618  * with the owner id this function returns.
 619  *
 620  * If the name is acquired or lost (for example another application
 621  * could acquire the name if you allow replacement or the application
 622  * currently owning the name exits), the handlers are also invoked.
 623  * If the #GDBusConnection that is used for attempting to own the name
 624  * closes, then @name_lost_handler is invoked since it is no longer
 625  * possible for other processes to access the process.
 626  *
 627  * You cannot use g_bus_own_name() several times for the same name (unless
 628  * interleaved with calls to g_bus_unown_name()) - only the first call
 629  * will work.
 630  *
 631  * Another guarantee is that invocations of @name_acquired_handler
 632  * and @name_lost_handler are guaranteed to alternate; that
 633  * is, if @name_acquired_handler is invoked then you are
 634  * guaranteed that the next time one of the handlers is invoked, it
 635  * will be @name_lost_handler. The reverse is also true.
 636  *
 637  * If you plan on exporting objects (using e.g.
 638  * g_dbus_connection_register_object()), note that it is generally too late
 639  * to export the objects in @name_acquired_handler. Instead, you can do this
 640  * in @bus_acquired_handler since you are guaranteed that this will run
 641  * before @name is requested from the bus.
 642  *
 643  * This behavior makes it very simple to write applications that wants
 644  * to [own names][gdbus-owning-names] and export objects.
 645  * Simply register objects to be exported in @bus_acquired_handler and
 646  * unregister the objects (if any) in @name_lost_handler.
 647  *
 648  * Returns: an identifier (never 0) that an be used with
 649  *     g_bus_unown_name() to stop owning the name.
 650  *
 651  * Since: 2.26
 652  */
 653 guint
 654 g_bus_own_name (GBusType                  bus_type,
 655                 const gchar              *name,
 656                 GBusNameOwnerFlags        flags,
 657                 GBusAcquiredCallback      bus_acquired_handler,
 658                 GBusNameAcquiredCallback  name_acquired_handler,
 659                 GBusNameLostCallback      name_lost_handler,
 660                 gpointer                  user_data,
 661                 GDestroyNotify            user_data_free_func)
 662 {
 663   Client *client;
 664
 665   g_return_val_if_fail (g_dbus_is_name (name) && !g_dbus_is_unique_name (name), 0);
 666
 667   G_LOCK (lock);
 668
 669   client = g_new0 (Client, 1);
 670   client->ref_count = 1;
 671   client->id = next_global_id++; /* TODO: uh oh, handle overflow */
 672   client->name = g_strdup (name);
 673   client->flags = flags;
 674   client->bus_acquired_handler = bus_acquired_handler;
 675   client->name_acquired_handler = name_acquired_handler;
 676   client->name_lost_handler = name_lost_handler;
 677   client->user_data = user_data;
 678   client->user_data_free_func = user_data_free_func;
 679   client->main_context = g_main_context_ref_thread_default ();
 680
 681   if (map_id_to_client == NULL)
 682     {
 683       map_id_to_client = g_hash_table_new (g_direct_hash, g_direct_equal);
 684     }
 685   g_hash_table_insert (map_id_to_client,
 686                        GUINT_TO_POINTER (client->id),
 687                        client);
 688
 689   g_bus_get (bus_type,
 690              NULL,
 691              connection_get_cb,
 692              client_ref (client));
 693
 694   G_UNLOCK (lock);
 695
 696   return client->id;
 697 }
 698
 699 typedef struct {
 700   GClosure *bus_acquired_closure;
 701   GClosure *name_acquired_closure;
 702   GClosure *name_lost_closure;
 703 } OwnNameData;
 704
 705 static OwnNameData *
 706 own_name_data_new (GClosure *bus_acquired_closure,
 707                    GClosure *name_acquired_closure,
 708                    GClosure *name_lost_closure)
 709 {
 710   OwnNameData *data;
 711
 712   data = g_new0 (OwnNameData, 1);
 713
 714   if (bus_acquired_closure != NULL)
 715     {
 716       data->bus_acquired_closure = g_closure_ref (bus_acquired_closure);
 717       g_closure_sink (bus_acquired_closure);
 718       if (G_CLOSURE_NEEDS_MARSHAL (bus_acquired_closure))
 719         g_closure_set_marshal (bus_acquired_closure, g_cclosure_marshal_generic);
 720     }
 721
 722   if (name_acquired_closure != NULL)
 723     {
 724       data->name_acquired_closure = g_closure_ref (name_acquired_closure);
 725       g_closure_sink (name_acquired_closure);
 726       if (G_CLOSURE_NEEDS_MARSHAL (name_acquired_closure))
 727         g_closure_set_marshal (name_acquired_closure, g_cclosure_marshal_generic);
 728     }
 729
 730   if (name_lost_closure != NULL)
 731     {
 732       data->name_lost_closure = g_closure_ref (name_lost_closure);
 733       g_closure_sink (name_lost_closure);
 734       if (G_CLOSURE_NEEDS_MARSHAL (name_lost_closure))
 735         g_closure_set_marshal (name_lost_closure, g_cclosure_marshal_generic);
 736     }
 737
 738   return data;
 739 }
 740
 741 static void
 742 own_with_closures_on_bus_acquired (GDBusConnection *connection,
 743                                    const gchar     *name,
 744                                    gpointer         user_data)
 745 {
 746   OwnNameData *data = user_data;
 747   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 748
 749   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 750   g_value_set_object (&params[0], connection);
 751
 752   g_value_init (&params[1], G_TYPE_STRING);
 753   g_value_set_string (&params[1], name);
 754
 755   g_closure_invoke (data->bus_acquired_closure, NULL, 2, params, NULL);
 756
 757   g_value_unset (params + 0);
 758   g_value_unset (params + 1);
 759 }
 760
 761 static void
 762 own_with_closures_on_name_acquired (GDBusConnection *connection,
 763                                     const gchar     *name,
 764                                     gpointer         user_data)
 765 {
 766   OwnNameData *data = user_data;
 767   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 768
 769   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 770   g_value_set_object (&params[0], connection);
 771
 772   g_value_init (&params[1], G_TYPE_STRING);
 773   g_value_set_string (&params[1], name);
 774
 775   g_closure_invoke (data->name_acquired_closure, NULL, 2, params, NULL);
 776
 777   g_value_unset (params + 0);
 778   g_value_unset (params + 1);
 779 }
 780
 781 static void
 782 own_with_closures_on_name_lost (GDBusConnection *connection,
 783                                 const gchar     *name,
 784                                 gpointer         user_data)
 785 {
 786   OwnNameData *data = user_data;
 787   GValue params[2] = { G_VALUE_INIT, G_VALUE_INIT };
 788
 789   g_value_init (&params[0], G_TYPE_DBUS_CONNECTION);
 790   g_value_set_object (&params[0], connection);
 791
 792   g_value_init (&params[1], G_TYPE_STRING);
 793   g_value_set_string (&params[1], name);
 794
 795   g_closure_invoke (data->name_lost_closure, NULL, 2, params, NULL);
 796
 797   g_value_unset (params + 0);
 798   g_value_unset (params + 1);
 799 }
 800
 801 static void
 802 bus_own_name_free_func (gpointer user_data)
 803 {
 804   OwnNameData *data = user_data;
 805
 806   if (data->bus_acquired_closure != NULL)
 807     g_closure_unref (data->bus_acquired_closure);
 808
 809   if (data->name_acquired_closure != NULL)
 810     g_closure_unref (data->name_acquired_closure);
 811
 812   if (data->name_lost_closure != NULL)
 813     g_closure_unref (data->name_lost_closure);
 814
 815   g_free (data);
 816 }
 817
 818 /**
 819  * g_bus_own_name_with_closures:
 820  * @bus_type: the type of bus to own a name on
 821  * @name: the well-known name to own
 822  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 823  * @bus_acquired_closure: (allow-none): #GClosure to invoke when connected to
 824  *     the bus of type @bus_type or %NULL
 825  * @name_acquired_closure: (allow-none): #GClosure to invoke when @name is
 826  *     acquired or %NULL
 827  * @name_lost_closure: (allow-none): #GClosure to invoke when @name is lost or
 828  *     %NULL
 829  *
 830  * Version of g_bus_own_name() using closures instead of callbacks for
 831  * easier binding in other languages.
 832  *
 833  * Returns: an identifier (never 0) that an be used with
 834  *     g_bus_unown_name() to stop owning the name.
 835  *
 836  * Rename to: g_bus_own_name
 837  *
 838  * Since: 2.26
 839  */
 840 guint
 841 g_bus_own_name_with_closures (GBusType            bus_type,
 842                               const gchar        *name,
 843                               GBusNameOwnerFlags  flags,
 844                               GClosure           *bus_acquired_closure,
 845                               GClosure           *name_acquired_closure,
 846                               GClosure           *name_lost_closure)
 847 {
 848   return g_bus_own_name (bus_type,
 849           name,
 850           flags,
 851           bus_acquired_closure != NULL ? own_with_closures_on_bus_acquired : NULL,
 852           name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
 853           name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
 854           own_name_data_new (bus_acquired_closure,
 855                              name_acquired_closure,
 856                              name_lost_closure),
 857           bus_own_name_free_func);
 858 }
 859
 860 /**
 861  * g_bus_own_name_on_connection_with_closures:
 862  * @connection: a #GDBusConnection
 863  * @name: the well-known name to own
 864  * @flags: a set of flags from the #GBusNameOwnerFlags enumeration
 865  * @name_acquired_closure: (allow-none): #GClosure to invoke when @name is
 866  *     acquired or %NULL
 867  * @name_lost_closure: (allow-none): #GClosure to invoke when @name is lost
 868  *     or %NULL
 869  *
 870  * Version of g_bus_own_name_on_connection() using closures instead of
 871  * callbacks for easier binding in other languages.
 872  *
 873  * Returns: an identifier (never 0) that an be used with
 874  *     g_bus_unown_name() to stop owning the name.
 875  *
 876  * Rename to: g_bus_own_name_on_connection
 877  *
 878  * Since: 2.26
 879  */
 880 guint
 881 g_bus_own_name_on_connection_with_closures (GDBusConnection    *connection,
 882                                             const gchar        *name,
 883                                             GBusNameOwnerFlags  flags,
 884                                             GClosure           *name_acquired_closure,
 885                                             GClosure           *name_lost_closure)
 886 {
 887   return g_bus_own_name_on_connection (connection,
 888           name,
 889           flags,
 890           name_acquired_closure != NULL ? own_with_closures_on_name_acquired : NULL,
 891           name_lost_closure != NULL ? own_with_closures_on_name_lost : NULL,
 892           own_name_data_new (NULL,
 893                              name_acquired_closure,
 894                              name_lost_closure),
 895           bus_own_name_free_func);
 896 }
 897
 898 /**
 899  * g_bus_unown_name:
 900  * @owner_id: an identifier obtained from g_bus_own_name()
 901  *
 902  * Stops owning a name.
 903  *
 904  * Since: 2.26
 905  */
 906 void
 907 g_bus_unown_name (guint owner_id)
 908 {
 909   Client *client;
 910
 911   g_return_if_fail (owner_id > 0);
 912
 913   client = NULL;
 914
 915   G_LOCK (lock);
 916   if (owner_id == 0 || map_id_to_client == NULL ||
 917       (client = g_hash_table_lookup (map_id_to_client, GUINT_TO_POINTER (owner_id))) == NULL)
 918     {
 919       g_warning ("Invalid id %d passed to g_bus_unown_name()", owner_id);
 920       goto out;
 921     }
 922
 923   client->cancelled = TRUE;
 924   g_warn_if_fail (g_hash_table_remove (map_id_to_client, GUINT_TO_POINTER (owner_id)));
 925
 926  out:
 927   G_UNLOCK (lock);
 928
 929   /* do callback without holding lock */
 930   if (client != NULL)
 931     {
 932       /* Release the name if needed */
 933       if (client->needs_release &&
 934           client->connection != NULL &&
 935           !g_dbus_connection_is_closed (client->connection))
 936         {
 937           GVariant *result;
 938           GError *error;
 939           guint32 release_name_reply;
 940
 941           /* TODO: it kinda sucks having to do a sync call to release the name - but if
 942            * we don't, then a subsequent grab of the name will make the bus daemon return
 943            * IN_QUEUE which will trigger name_lost().
 944            *
 945            * I believe this is a bug in the bus daemon.
 946            */
 947           error = NULL;
 948 #if 0
 949           if (G_IS_KDBUS_CONNECTION (g_dbus_connection_get_stream (client->connection)))
 950             result = _g_kdbus_ReleaseName (client->connection, client->name, &error);
 951           else
 952 #endif
 953             result = g_dbus_connection_call_sync (client->connection,
 954                                                   "org.freedesktop.DBus",  /* bus name */
 955                                                   "/org/freedesktop/DBus", /* object path */
 956                                                   "org.freedesktop.DBus",  /* interface name */
 957                                                   "ReleaseName",           /* method name */
 958                                                   g_variant_new ("(s)", client->name),
 959                                                   G_VARIANT_TYPE ("(u)"),
 960                                                   G_DBUS_CALL_FLAGS_NONE,
 961                                                   -1,
 962                                                   NULL,
 963                                                   &error);
 964           if (result == NULL)
 965             {
 966               g_warning ("Error releasing name %s: %s", client->name, error->message);
 967               g_error_free (error);
 968             }
 969           else
 970             {
 971               g_variant_get (result, "(u)", &release_name_reply);
 972               if (release_name_reply != 1 /* DBUS_RELEASE_NAME_REPLY_RELEASED */)
 973                 {
 974                   g_warning ("Unexpected reply %d when releasing name %s", release_name_reply, client->name);
 975                 }
 976               g_variant_unref (result);
 977             }
 978         }
 979
 980       if (client->disconnected_signal_handler_id > 0)
 981         g_signal_handler_disconnect (client->connection, client->disconnected_signal_handler_id);
 982       if (client->name_acquired_subscription_id > 0)
 983         g_dbus_connection_signal_unsubscribe (client->connection, client->name_acquired_subscription_id);
 984       if (client->name_lost_subscription_id > 0)
 985         g_dbus_connection_signal_unsubscribe (client->connection, client->name_lost_subscription_id);
 986       client->disconnected_signal_handler_id = 0;
 987       client->name_acquired_subscription_id = 0;
 988       client->name_lost_subscription_id = 0;
 989       if (client->connection != NULL)
 990         {
 991           g_object_unref (client->connection);
 992           client->connection = NULL;
 993         }
 994
 995       client_unref (client);
 996     }
 997 }