gio/gapplication.c

   1 /*
   2  * Copyright © 2010 Codethink Limited
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License as published
   6  * by the Free Software Foundation; either version 2 of the licence or (at
   7  * your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General
  15  * Public License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  *
  19  * Authors: Ryan Lortie <desrt@desrt.ca>
  20  */
  21
  22 /* Prologue {{{1 */
  23 #include "config.h"
  24
  25 #include "gapplication.h"
  26
  27 #include "gapplicationcommandline.h"
  28 #include "gapplicationimpl.h"
  29 #include "gactiongroup.h"
  30 #include "gsettings.h"
  31
  32 #include "gioenumtypes.h"
  33 #include "gioenums.h"
  34 #include "gfile.h"
  35
  36 #include "glibintl.h"
  37
  38 #include <string.h>
  39
  40 /**
  41  * SECTION:gapplication
  42  * @title: GApplication
  43  * @short_description: Core application class
  44  *
  45  * A #GApplication is the foundation of an application, unique for a
  46  * given application identifier.  The GApplication class wraps some
  47  * low-level platform-specific services and is intended to act as the
  48  * foundation for higher-level application classes such as
  49  * #GtkApplication or #MxApplication.  In general, you should not use
  50  * this class outside of a higher level framework.
  51  *
  52  * One of the core features that GApplication provides is process
  53  * uniqueness, in the context of a "session".  The session concept is
  54  * platform-dependent, but corresponds roughly to a graphical desktop
  55  * login.  When your application is launched again, its arguments
  56  * are passed through platform communication to the already running
  57  * program. The already running instance of the program is called the
  58  * <firstterm>primary instance</firstterm>.
  59  *
  60  * Before using GApplication, you must choose an "application identifier".
  61  * The expected form of an application identifier is very close to that of
  62  * of a <ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html#message-protocol-names-interface">DBus bus name</ulink>.
  63  * Examples include: "com.example.MyApp", "org.example.internal-apps.Calculator".
  64  * For details on valid application identifiers, see
  65  * g_application_id_is_valid().
  66  *
  67  * The application identifier is claimed by the application as a
  68  * well-known bus name on the user's session bus.  This means that the
  69  * uniqueness of your application is scoped to the current session.  It
  70  * also means that your application may provide additional services
  71  * (through registration of other object paths) at that bus name.
  72  *
  73  * The registration of these object paths should be done with the shared
  74  * GDBus session bus.  Note that due to the internal architecture of
  75  * GDBus, method calls can be dispatched at any time (even if a main
  76  * loop is not running).  For this reason, you must ensure that any
  77  * object paths that you wish to register are registered before
  78  * #GApplication attempts to acquire the bus name of your application
  79  * (which happens in g_application_register()).  Unfortunately, this
  80  * means that you cannot use g_application_get_is_remote() to decide if
  81  * you want to register object paths.
  82  *
  83  * GApplication provides convenient life cycle management by maintaining
  84  * a <firstterm>use count</firstterm> for the primary application instance.
  85  * The use count can be changed using g_application_hold() and
  86  * g_application_release(). If it drops to zero, the application exits.
  87  *
  88  * GApplication also implements the #GActionGroup interface and lets you
  89  * easily export actions by adding them with g_application_set_action_group().
  90  * When invoking an action by calling g_action_group_activate_action() on
  91  * the application, it is always invoked in the primary instance.
  92  *
  93  * There is a number of different entry points into a #GApplication:
  94  * <itemizedlist>
  95  * <listitem>via 'Activate' (i.e. just starting the application)</listitem>
  96  * <listitem>via 'Open' (i.e. opening some files)</listitem>
  97  * <listitem>by handling a command-line</listitem>
  98  * <listitem>via activating an action</listitem>
  99  * </itemizedlist>
 100  * The #GApplication::startup signal lets you handle the application
 101  * initialization for all of these in a single place.
 102  *
 103  * Regardless of which of these entry points is used to start the application,
 104  * GApplication passes some <firstterm id="platform-data">platform
 105  * data</firstterm> from the launching instance to the primary instance,
 106  * in the form of a #GVariant dictionary mapping strings to variants.
 107  * To use platform data, override the @before_emit or @after_emit virtual
 108  * functions in your #GApplication subclass. When dealing with
 109  * #GApplicationCommandline objects, the platform data is directly
 110  * available via g_application_command_line_get_cwd(),
 111  * g_application_command_line_get_environ() and
 112  * g_application_command_line_get_platform_data().
 113  *
 114  * As the name indicates, the platform data may vary depending on the
 115  * operating system, but it always includes the current directory (key
 116  * "cwd"), and optionally the environment (ie the set of environment
 117  * variables and their values) of the calling process (key "environ").
 118  * The environment is only added to the platform data if the
 119  * #G_APPLICATION_SEND_ENVIONMENT flag is set. GApplication subclasses
 120  * can add their own platform data by overriding the @add_platform_data
 121  * virtual function. For instance, #GtkApplication adds startup notification
 122  * data in this way.
 123  *
 124  * To parse commandline arguments you may handle the
 125  * #GApplication::command-line signal or override the local_command_line()
 126  * vfunc, to parse them in either the primary instance or the local instance,
 127  * respectively.
 128  *
 129  * <example id="gapplication-example-open"><title>Opening files with a GApplication</title>
 130  * <programlisting>
 131  * <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gapplication-example-open.c">
 132  *   <xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback>
 133  * </xi:include>
 134  * </programlisting>
 135  * </example>
 136  *
 137  * <example id="gapplication-example-actions"><title>A GApplication with actions</title>
 138  * <programlisting>
 139  * <xi:include xmlns:xi="http://www.w3.org/2001/XInclude" parse="text" href="../../../../gio/tests/gapplication-example-actions.c">
 140  *   <xi:fallback>FIXME: MISSING XINCLUDE CONTENT</xi:fallback>
 141  * </xi:include>
 142  * </programlisting>
 143  * </example>
 144  */
 145
 146 struct _GApplicationPrivate
 147 {
 148   GApplicationFlags  flags;
 149   gchar             *id;
 150
 151   GActionGroup      *actions;
 152
 153   guint              inactivity_timeout_id;
 154   guint              inactivity_timeout;
 155   guint              use_count;
 156
 157   guint              is_registered : 1;
 158   guint              is_remote : 1;
 159   guint              did_startup : 1;
 160   guint              did_shutdown : 1;
 161
 162   GActionGroup      *remote_actions;
 163   GApplicationImpl  *impl;
 164 };
 165
 166 enum
 167 {
 168   PROP_NONE,
 169   PROP_APPLICATION_ID,
 170   PROP_FLAGS,
 171   PROP_IS_REGISTERED,
 172   PROP_IS_REMOTE,
 173   PROP_INACTIVITY_TIMEOUT,
 174   PROP_ACTION_GROUP
 175 };
 176
 177 enum
 178 {
 179   SIGNAL_STARTUP,
 180   SIGNAL_SHUTDOWN,
 181   SIGNAL_ACTIVATE,
 182   SIGNAL_OPEN,
 183   SIGNAL_ACTION,
 184   SIGNAL_COMMAND_LINE,
 185   NR_SIGNALS
 186 };
 187
 188 static guint g_application_signals[NR_SIGNALS];
 189
 190 static void g_application_action_group_iface_init (GActionGroupInterface *);
 191 G_DEFINE_TYPE_WITH_CODE (GApplication, g_application, G_TYPE_OBJECT,
 192  G_IMPLEMENT_INTERFACE (G_TYPE_ACTION_GROUP,
 193    g_application_action_group_iface_init))
 194
 195 /* vfunc defaults {{{1 */
 196 static void
 197 g_application_real_before_emit (GApplication *application,
 198                                 GVariant     *platform_data)
 199 {
 200 }
 201
 202 static void
 203 g_application_real_after_emit (GApplication *application,
 204                                GVariant     *platform_data)
 205 {
 206 }
 207
 208 static void
 209 g_application_real_startup (GApplication *application)
 210 {
 211   application->priv->did_startup = TRUE;
 212 }
 213
 214 static void
 215 g_application_real_shutdown (GApplication *application)
 216 {
 217   application->priv->did_shutdown = TRUE;
 218 }
 219
 220 static void
 221 g_application_real_activate (GApplication *application)
 222 {
 223   if (!g_signal_has_handler_pending (application,
 224                                      g_application_signals[SIGNAL_ACTIVATE],
 225                                      0, TRUE) &&
 226       G_APPLICATION_GET_CLASS (application)->activate == g_application_real_activate)
 227     {
 228       static gboolean warned;
 229
 230       if (warned)
 231         return;
 232
 233       g_warning ("Your application does not implement "
 234                  "g_application_activate() and has no handlers connected "
 235                  "to the 'activate' signal.  It should do one of these.");
 236       warned = TRUE;
 237     }
 238 }
 239
 240 static void
 241 g_application_real_open (GApplication  *application,
 242                          GFile        **files,
 243                          gint           n_files,
 244                          const gchar   *hint)
 245 {
 246   if (!g_signal_has_handler_pending (application,
 247                                      g_application_signals[SIGNAL_OPEN],
 248                                      0, TRUE) &&
 249       G_APPLICATION_GET_CLASS (application)->open == g_application_real_open)
 250     {
 251       static gboolean warned;
 252
 253       if (warned)
 254         return;
 255
 256       g_warning ("Your application claims to support opening files "
 257                  "but does not implement g_application_open() and has no "
 258                  "handlers connected to the 'open' signal.");
 259       warned = TRUE;
 260     }
 261 }
 262
 263 static int
 264 g_application_real_command_line (GApplication            *application,
 265                                  GApplicationCommandLine *cmdline)
 266 {
 267   if (!g_signal_has_handler_pending (application,
 268                                      g_application_signals[SIGNAL_COMMAND_LINE],
 269                                      0, TRUE) &&
 270       G_APPLICATION_GET_CLASS (application)->command_line == g_application_real_command_line)
 271     {
 272       static gboolean warned;
 273
 274       if (warned)
 275         return 1;
 276
 277       g_warning ("Your application claims to support custom command line "
 278                  "handling but does not implement g_application_command_line() "
 279                  "and has no handlers connected to the 'command-line' signal.");
 280
 281       warned = TRUE;
 282     }
 283
 284     return 1;
 285 }
 286
 287 static gboolean
 288 g_application_real_local_command_line (GApplication   *application,
 289                                        gchar        ***arguments,
 290                                        int            *exit_status)
 291 {
 292   if (application->priv->flags & G_APPLICATION_HANDLES_COMMAND_LINE)
 293     return FALSE;
 294
 295   else
 296     {
 297       GError *error = NULL;
 298       gint n_args;
 299
 300       if (!g_application_register (application, NULL, &error))
 301         {
 302           g_critical ("%s", error->message);
 303           g_error_free (error);
 304           *exit_status = 1;
 305           return TRUE;
 306         }
 307
 308       n_args = g_strv_length (*arguments);
 309
 310       if (application->priv->flags & G_APPLICATION_IS_SERVICE)
 311         {
 312           if ((*exit_status = n_args > 1))
 313             {
 314               g_printerr ("GApplication service mode takes no arguments.\n");
 315               application->priv->flags &= ~G_APPLICATION_IS_SERVICE;
 316             }
 317
 318           return TRUE;
 319         }
 320
 321       if (n_args <= 1)
 322         {
 323           g_application_activate (application);
 324           *exit_status = 0;
 325         }
 326
 327       else
 328         {
 329           if (~application->priv->flags & G_APPLICATION_HANDLES_OPEN)
 330             {
 331               g_critical ("This application can not open files.");
 332               *exit_status = 1;
 333             }
 334           else
 335             {
 336               GFile **files;
 337               gint n_files;
 338               gint i;
 339
 340               n_files = n_args - 1;
 341               files = g_new (GFile *, n_files);
 342
 343               for (i = 0; i < n_files; i++)
 344                 files[i] = g_file_new_for_commandline_arg ((*arguments)[i + 1]);
 345
 346               g_application_open (application, files, n_files, "");
 347
 348               for (i = 0; i < n_files; i++)
 349                 g_object_unref (files[i]);
 350               g_free (files);
 351
 352               *exit_status = 0;
 353             }
 354         }
 355
 356       return TRUE;
 357     }
 358 }
 359
 360 static void
 361 g_application_real_add_platform_data (GApplication    *application,
 362                                       GVariantBuilder *builder)
 363 {
 364 }
 365
 366 /* GObject implementation stuff {{{1 */
 367 static void
 368 g_application_set_property (GObject      *object,
 369                             guint         prop_id,
 370                             const GValue *value,
 371                             GParamSpec   *pspec)
 372 {
 373   GApplication *application = G_APPLICATION (object);
 374
 375   switch (prop_id)
 376     {
 377     case PROP_APPLICATION_ID:
 378       g_application_set_application_id (application,
 379                                         g_value_get_string (value));
 380       break;
 381
 382     case PROP_FLAGS:
 383       g_application_set_flags (application, g_value_get_flags (value));
 384       break;
 385
 386     case PROP_INACTIVITY_TIMEOUT:
 387       g_application_set_inactivity_timeout (application,
 388                                             g_value_get_uint (value));
 389       break;
 390
 391     case PROP_ACTION_GROUP:
 392       g_application_set_action_group (application,
 393                                       g_value_get_object (value));
 394       break;
 395
 396     default:
 397       g_assert_not_reached ();
 398     }
 399 }
 400
 401 /**
 402  * g_application_set_action_group:
 403  * @application: a #GApplication
 404  * @action_group: (allow-none): a #GActionGroup, or %NULL
 405  *
 406  * Sets or unsets the group of actions associated with the application.
 407  *
 408  * These actions are the actions that can be remotely invoked.
 409  *
 410  * It is an error to call this function after the application has been
 411  * registered.
 412  *
 413  * Since: 2.28
 414  **/
 415 void
 416 g_application_set_action_group (GApplication *application,
 417                                 GActionGroup *action_group)
 418 {
 419   g_return_if_fail (G_IS_APPLICATION (application));
 420   g_return_if_fail (!application->priv->is_registered);
 421
 422   if (application->priv->actions != NULL)
 423     g_object_unref (application->priv->actions);
 424
 425   application->priv->actions = action_group;
 426
 427   if (application->priv->actions != NULL)
 428     g_object_ref (application->priv->actions);
 429 }
 430
 431 static void
 432 g_application_get_property (GObject    *object,
 433                             guint       prop_id,
 434                             GValue     *value,
 435                             GParamSpec *pspec)
 436 {
 437   GApplication *application = G_APPLICATION (object);
 438
 439   switch (prop_id)
 440     {
 441     case PROP_APPLICATION_ID:
 442       g_value_set_string (value,
 443                           g_application_get_application_id (application));
 444       break;
 445
 446     case PROP_FLAGS:
 447       g_value_set_flags (value,
 448                          g_application_get_flags (application));
 449       break;
 450
 451     case PROP_IS_REGISTERED:
 452       g_value_set_boolean (value,
 453                            g_application_get_is_registered (application));
 454       break;
 455
 456     case PROP_IS_REMOTE:
 457       g_value_set_boolean (value,
 458                            g_application_get_is_remote (application));
 459       break;
 460
 461     case PROP_INACTIVITY_TIMEOUT:
 462       g_value_set_uint (value,
 463                         g_application_get_inactivity_timeout (application));
 464       break;
 465
 466     default:
 467       g_assert_not_reached ();
 468     }
 469 }
 470
 471 static void
 472 g_application_constructed (GObject *object)
 473 {
 474   GApplication *application = G_APPLICATION (object);
 475
 476   g_assert (application->priv->id != NULL);
 477
 478   if (g_application_get_default () == NULL)
 479     g_application_set_default (application);
 480 }
 481
 482 static void
 483 g_application_finalize (GObject *object)
 484 {
 485   GApplication *application = G_APPLICATION (object);
 486
 487   if (application->priv->impl)
 488     g_application_impl_destroy (application->priv->impl);
 489   g_free (application->priv->id);
 490
 491   if (g_application_get_default () == application)
 492     g_application_set_default (NULL);
 493
 494   G_OBJECT_CLASS (g_application_parent_class)
 495     ->finalize (object);
 496 }
 497
 498 static void
 499 g_application_init (GApplication *application)
 500 {
 501   application->priv = G_TYPE_INSTANCE_GET_PRIVATE (application,
 502                                                    G_TYPE_APPLICATION,
 503                                                    GApplicationPrivate);
 504 }
 505
 506 static void
 507 g_application_class_init (GApplicationClass *class)
 508 {
 509   GObjectClass *object_class = G_OBJECT_CLASS (class);
 510
 511   object_class->constructed = g_application_constructed;
 512   object_class->finalize = g_application_finalize;
 513   object_class->get_property = g_application_get_property;
 514   object_class->set_property = g_application_set_property;
 515
 516   class->before_emit = g_application_real_before_emit;
 517   class->after_emit = g_application_real_after_emit;
 518   class->startup = g_application_real_startup;
 519   class->shutdown = g_application_real_shutdown;
 520   class->activate = g_application_real_activate;
 521   class->open = g_application_real_open;
 522   class->command_line = g_application_real_command_line;
 523   class->local_command_line = g_application_real_local_command_line;
 524   class->add_platform_data = g_application_real_add_platform_data;
 525
 526   g_object_class_install_property (object_class, PROP_APPLICATION_ID,
 527     g_param_spec_string ("application-id",
 528                          P_("Application identifier"),
 529                          P_("The unique identifier for the application"),
 530                          NULL, G_PARAM_READWRITE | G_PARAM_CONSTRUCT |
 531                          G_PARAM_STATIC_STRINGS));
 532
 533   g_object_class_install_property (object_class, PROP_FLAGS,
 534     g_param_spec_flags ("flags",
 535                         P_("Application flags"),
 536                         P_("Flags specifying the behaviour of the application"),
 537                         G_TYPE_APPLICATION_FLAGS, G_APPLICATION_FLAGS_NONE,
 538                         G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 539
 540   g_object_class_install_property (object_class, PROP_IS_REGISTERED,
 541     g_param_spec_boolean ("is-registered",
 542                           P_("Is registered"),
 543                           P_("If g_application_register() has been called"),
 544                           FALSE, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
 545
 546   g_object_class_install_property (object_class, PROP_IS_REMOTE,
 547     g_param_spec_boolean ("is-remote",
 548                           P_("Is remote"),
 549                           P_("If this application instance is remote"),
 550                           FALSE, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
 551
 552   g_object_class_install_property (object_class, PROP_INACTIVITY_TIMEOUT,
 553     g_param_spec_uint ("inactivity-timeout",
 554                        P_("Inactivity timeout"),
 555                        P_("Time (ms) to stay alive after becoming idle"),
 556                        0, G_MAXUINT, 0,
 557                        G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 558
 559   g_object_class_install_property (object_class, PROP_ACTION_GROUP,
 560     g_param_spec_object ("action-group",
 561                          P_("Action group"),
 562                          P_("The group of actions that the application exports"),
 563                          G_TYPE_ACTION_GROUP,
 564                          G_PARAM_WRITABLE | G_PARAM_STATIC_STRINGS));
 565
 566   /**
 567    * GApplication::startup:
 568    * @application: the application
 569    *
 570    * The ::startup signal is emitted on the primary instance immediately
 571    * after registration. See g_application_register().
 572    */
 573   g_application_signals[SIGNAL_STARTUP] =
 574     g_signal_new ("startup", G_TYPE_APPLICATION, G_SIGNAL_RUN_LAST,
 575                   G_STRUCT_OFFSET (GApplicationClass, startup),
 576                   NULL, NULL, g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0);
 577
 578   /**
 579    * GApplication::shutdown:
 580    * @application: the application
 581    *
 582    * The ::shutdown signal is emitted only on the registered primary instance
 583    * immediately after the main loop terminates.
 584    */
 585   g_application_signals[SIGNAL_SHUTDOWN] =
 586     g_signal_new ("shutdown", G_TYPE_APPLICATION, G_SIGNAL_RUN_LAST,
 587                   G_STRUCT_OFFSET (GApplicationClass, shutdown),
 588                   NULL, NULL, g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0);
 589
 590   /**
 591    * GApplication::activate:
 592    * @application: the application
 593    *
 594    * The ::activate signal is emitted on the primary instance when an
 595    * activation occurs. See g_application_activate().
 596    */
 597   g_application_signals[SIGNAL_ACTIVATE] =
 598     g_signal_new ("activate", G_TYPE_APPLICATION, G_SIGNAL_RUN_LAST,
 599                   G_STRUCT_OFFSET (GApplicationClass, activate),
 600                   NULL, NULL, g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0);
 601
 602
 603   /**
 604    * GApplication::open:
 605    * @application: the application
 606    * @files: (array length=n_files) (element-type GFile): an array of #GFiles
 607    * @n_files: the length of @files
 608    * @hint: a hint provided by the calling instance
 609    *
 610    * The ::open signal is emitted on the primary instance when there are
 611    * files to open. See g_application_open() for more information.
 612    */
 613   g_application_signals[SIGNAL_OPEN] =
 614     g_signal_new ("open", G_TYPE_APPLICATION, G_SIGNAL_RUN_LAST,
 615                   G_STRUCT_OFFSET (GApplicationClass, open),
 616                   NULL, NULL, NULL,
 617                   G_TYPE_NONE, 3, G_TYPE_POINTER, G_TYPE_INT, G_TYPE_STRING);
 618
 619   /**
 620    * GApplication::command-line:
 621    * @application: the application
 622    * @command_line: a #GApplicationCommandLine representing the
 623    *     passed commandline
 624    *
 625    * The ::command-line signal is emitted on the primary instance when
 626    * a commandline is not handled locally. See g_application_run() and
 627    * the #GApplicationCommandline documentation for more information.
 628    *
 629    * Returns: An integer that is set as the exit status for the calling
 630    *   process. See g_application_command_line_set_exit_status().
 631    */
 632   g_application_signals[SIGNAL_COMMAND_LINE] =
 633     g_signal_new ("command-line", G_TYPE_APPLICATION, G_SIGNAL_RUN_LAST,
 634                   G_STRUCT_OFFSET (GApplicationClass, command_line),
 635                   g_signal_accumulator_first_wins, NULL,
 636                   NULL,
 637                   G_TYPE_INT, 1, G_TYPE_APPLICATION_COMMAND_LINE);
 638
 639   g_type_class_add_private (class, sizeof (GApplicationPrivate));
 640 }
 641
 642 static GVariant *
 643 get_platform_data (GApplication *application)
 644 {
 645   GVariantBuilder *builder;
 646   GVariant *result;
 647
 648   builder = g_variant_builder_new (G_VARIANT_TYPE ("a{sv}"));
 649
 650   {
 651     gchar *cwd = g_get_current_dir ();
 652     g_variant_builder_add (builder, "{sv}", "cwd",
 653                            g_variant_new_bytestring (cwd));
 654     g_free (cwd);
 655   }
 656
 657   if (application->priv->flags & G_APPLICATION_SEND_ENVIRONMENT)
 658     {
 659       GVariant *array;
 660       gchar **envp;
 661
 662       envp = g_get_environ ();
 663       array = g_variant_new_bytestring_array ((const gchar **) envp, -1);
 664       g_strfreev (envp);
 665
 666       g_variant_builder_add (builder, "{sv}", "environ", array);
 667     }
 668
 669   G_APPLICATION_GET_CLASS (application)->
 670     add_platform_data (application, builder);
 671
 672   result = g_variant_builder_end (builder);
 673   g_variant_builder_unref (builder);
 674
 675   return result;
 676 }
 677
 678 /* Application ID validity {{{1 */
 679
 680 /**
 681  * g_application_id_is_valid:
 682  * @application_id: a potential application identifier
 683  *
 684  * Checks if @application_id is a valid application identifier.
 685  *
 686  * A valid ID is required for calls to g_application_new() and
 687  * g_application_set_application_id().
 688  *
 689  * For convenience, the restrictions on application identifiers are
 690  * reproduced here:
 691  * <itemizedlist>
 692  *   <listitem>Application identifiers must contain only the ASCII characters "[A-Z][a-z][0-9]_-." and must not begin with a digit.</listitem>
 693  *   <listitem>Application identifiers must contain at least one '.' (period) character (and thus at least three elements).</listitem>
 694  *   <listitem>Application identifiers must not begin or end with a '.' (period) character.</listitem>
 695  *   <listitem>Application identifiers must not contain consecutive '.' (period) characters.</listitem>
 696  *   <listitem>Application identifiers must not exceed 255 characters.</listitem>
 697  * </itemizedlist>
 698  *
 699  * Returns: %TRUE if @application_id is valid
 700  **/
 701 gboolean
 702 g_application_id_is_valid (const gchar *application_id)
 703 {
 704   gsize len;
 705   gboolean allow_dot;
 706   gboolean has_dot;
 707
 708   len = strlen (application_id);
 709
 710   if (len > 255)
 711     return FALSE;
 712
 713   if (!g_ascii_isalpha (application_id[0]))
 714     return FALSE;
 715
 716   if (application_id[len-1] == '.')
 717     return FALSE;
 718
 719   application_id++;
 720   allow_dot = TRUE;
 721   has_dot = FALSE;
 722   for (; *application_id; application_id++)
 723     {
 724       if (g_ascii_isalnum (*application_id) ||
 725           (*application_id == '-') ||
 726           (*application_id == '_'))
 727         {
 728           allow_dot = TRUE;
 729         }
 730       else if (allow_dot && *application_id == '.')
 731         {
 732           has_dot = TRUE;
 733           allow_dot = FALSE;
 734         }
 735       else
 736         return FALSE;
 737     }
 738
 739   if (!has_dot)
 740     return FALSE;
 741
 742   return TRUE;
 743 }
 744
 745 /* Public Constructor {{{1 */
 746 /**
 747  * g_application_new:
 748  * @application_id: the application id
 749  * @flags: the application flags
 750  *
 751  * Creates a new #GApplication instance.
 752  *
 753  * This function calls g_type_init() for you.
 754  *
 755  * The application id must be valid.  See g_application_id_is_valid().
 756  *
 757  * Returns: a new #GApplication instance
 758  **/
 759 GApplication *
 760 g_application_new (const gchar       *application_id,
 761                    GApplicationFlags  flags)
 762 {
 763   g_return_val_if_fail (g_application_id_is_valid (application_id), NULL);
 764
 765   g_type_init ();
 766
 767   return g_object_new (G_TYPE_APPLICATION,
 768                        "application-id", application_id,
 769                        "flags", flags,
 770                        NULL);
 771 }
 772
 773 /* Simple get/set: application id, flags, inactivity timeout {{{1 */
 774 /**
 775  * g_application_get_application_id:
 776  * @application: a #GApplication
 777  *
 778  * Gets the unique identifier for @application.
 779  *
 780  * Returns: the identifier for @application, owned by @application
 781  *
 782  * Since: 2.28
 783  **/
 784 const gchar *
 785 g_application_get_application_id (GApplication *application)
 786 {
 787   g_return_val_if_fail (G_IS_APPLICATION (application), NULL);
 788
 789   return application->priv->id;
 790 }
 791
 792 /**
 793  * g_application_set_application_id:
 794  * @application: a #GApplication
 795  * @application_id: the identifier for @application
 796  *
 797  * Sets the unique identifier for @application.
 798  *
 799  * The application id can only be modified if @application has not yet
 800  * been registered.
 801  *
 802  * The application id must be valid.  See g_application_id_is_valid().
 803  *
 804  * Since: 2.28
 805  **/
 806 void
 807 g_application_set_application_id (GApplication *application,
 808                                   const gchar  *application_id)
 809 {
 810   g_return_if_fail (G_IS_APPLICATION (application));
 811
 812   if (g_strcmp0 (application->priv->id, application_id) != 0)
 813     {
 814       g_return_if_fail (g_application_id_is_valid (application_id));
 815       g_return_if_fail (!application->priv->is_registered);
 816
 817       g_free (application->priv->id);
 818       application->priv->id = g_strdup (application_id);
 819
 820       g_object_notify (G_OBJECT (application), "application-id");
 821     }
 822 }
 823
 824 /**
 825  * g_application_get_flags:
 826  * @application: a #GApplication
 827  *
 828  * Gets the flags for @application.
 829  *
 830  * See #GApplicationFlags.
 831  *
 832  * Returns: the flags for @application
 833  *
 834  * Since: 2.28
 835  **/
 836 GApplicationFlags
 837 g_application_get_flags (GApplication *application)
 838 {
 839   g_return_val_if_fail (G_IS_APPLICATION (application), 0);
 840
 841   return application->priv->flags;
 842 }
 843
 844 /**
 845  * g_application_set_flags:
 846  * @application: a #GApplication
 847  * @flags: the flags for @application
 848  *
 849  * Sets the flags for @application.
 850  *
 851  * The flags can only be modified if @application has not yet been
 852  * registered.
 853  *
 854  * See #GApplicationFlags.
 855  *
 856  * Since: 2.28
 857  **/
 858 void
 859 g_application_set_flags (GApplication      *application,
 860                          GApplicationFlags  flags)
 861 {
 862   g_return_if_fail (G_IS_APPLICATION (application));
 863
 864   if (application->priv->flags != flags)
 865     {
 866       g_return_if_fail (!application->priv->is_registered);
 867
 868       application->priv->flags = flags;
 869
 870       g_object_notify (G_OBJECT (application), "flags");
 871     }
 872 }
 873
 874 /**
 875  * g_application_get_inactivity_timeout:
 876  * @application: a #GApplication
 877  *
 878  * Gets the current inactivity timeout for the application.
 879  *
 880  * This is the amount of time (in milliseconds) after the last call to
 881  * g_application_release() before the application stops running.
 882  *
 883  * Returns: the timeout, in milliseconds
 884  *
 885  * Since: 2.28
 886  **/
 887 guint
 888 g_application_get_inactivity_timeout (GApplication *application)
 889 {
 890   g_return_val_if_fail (G_IS_APPLICATION (application), 0);
 891
 892   return application->priv->inactivity_timeout;
 893 }
 894
 895 /**
 896  * g_application_set_inactivity_timeout:
 897  * @application: a #GApplication
 898  * @inactivity_timeout: the timeout, in milliseconds
 899  *
 900  * Sets the current inactivity timeout for the application.
 901  *
 902  * This is the amount of time (in milliseconds) after the last call to
 903  * g_application_release() before the application stops running.
 904  *
 905  * This call has no side effects of its own.  The value set here is only
 906  * used for next time g_application_release() drops the use count to
 907  * zero.  Any timeouts currently in progress are not impacted.
 908  *
 909  * Since: 2.28
 910  **/
 911 void
 912 g_application_set_inactivity_timeout (GApplication *application,
 913                                       guint         inactivity_timeout)
 914 {
 915   g_return_if_fail (G_IS_APPLICATION (application));
 916
 917   if (application->priv->inactivity_timeout != inactivity_timeout)
 918     {
 919       application->priv->inactivity_timeout = inactivity_timeout;
 920
 921       g_object_notify (G_OBJECT (application), "inactivity-timeout");
 922     }
 923 }
 924 /* Read-only property getters (is registered, is remote) {{{1 */
 925 /**
 926  * g_application_get_is_registered:
 927  * @application: a #GApplication
 928  *
 929  * Checks if @application is registered.
 930  *
 931  * An application is registered if g_application_register() has been
 932  * successfully called.
 933  *
 934  * Returns: %TRUE if @application is registered
 935  *
 936  * Since: 2.28
 937  **/
 938 gboolean
 939 g_application_get_is_registered (GApplication *application)
 940 {
 941   g_return_val_if_fail (G_IS_APPLICATION (application), FALSE);
 942
 943   return application->priv->is_registered;
 944 }
 945
 946 /**
 947  * g_application_get_is_remote:
 948  * @application: a #GApplication
 949  *
 950  * Checks if @application is remote.
 951  *
 952  * If @application is remote then it means that another instance of
 953  * application already exists (the 'primary' instance).  Calls to
 954  * perform actions on @application will result in the actions being
 955  * performed by the primary instance.
 956  *
 957  * The value of this property cannot be accessed before
 958  * g_application_register() has been called.  See
 959  * g_application_get_is_registered().
 960  *
 961  * Returns: %TRUE if @application is remote
 962  *
 963  * Since: 2.28
 964  **/
 965 gboolean
 966 g_application_get_is_remote (GApplication *application)
 967 {
 968   g_return_val_if_fail (G_IS_APPLICATION (application), FALSE);
 969   g_return_val_if_fail (application->priv->is_registered, FALSE);
 970
 971   return application->priv->is_remote;
 972 }
 973
 974 /* Register {{{1 */
 975 /**
 976  * g_application_register:
 977  * @application: a #GApplication
 978  * @cancellable: a #GCancellable, or %NULL
 979  * @error: a pointer to a NULL #GError, or %NULL
 980  *
 981  * Attempts registration of the application.
 982  *
 983  * This is the point at which the application discovers if it is the
 984  * primary instance or merely acting as a remote for an already-existing
 985  * primary instance.  This is implemented by attempting to acquire the
 986  * application identifier as a unique bus name on the session bus using
 987  * GDBus.
 988  *
 989  * Due to the internal architecture of GDBus, method calls can be
 990  * dispatched at any time (even if a main loop is not running).  For
 991  * this reason, you must ensure that any object paths that you wish to
 992  * register are registered before calling this function.
 993  *
 994  * If the application has already been registered then %TRUE is
 995  * returned with no work performed.
 996  *
 997  * The #GApplication::startup signal is emitted if registration succeeds
 998  * and @application is the primary instance.
 999  *
1000  * In the event of an error (such as @cancellable being cancelled, or a
1001  * failure to connect to the session bus), %FALSE is returned and @error
1002  * is set appropriately.
1003  *
1004  * Note: the return value of this function is not an indicator that this
1005  * instance is or is not the primary instance of the application.  See
1006  * g_application_get_is_remote() for that.
1007  *
1008  * Returns: %TRUE if registration succeeded
1009  *
1010  * Since: 2.28
1011  **/
1012 gboolean
1013 g_application_register (GApplication  *application,
1014                         GCancellable  *cancellable,
1015                         GError       **error)
1016 {
1017   g_return_val_if_fail (G_IS_APPLICATION (application), FALSE);
1018
1019   if (!application->priv->is_registered)
1020     {
1021       if (~application->priv->flags & G_APPLICATION_NON_UNIQUE)
1022         {
1023           application->priv->impl =
1024             g_application_impl_register (application, application->priv->id,
1025                                          application->priv->flags,
1026                                          &application->priv->remote_actions,
1027                                          cancellable, error);
1028
1029           if (application->priv->impl == NULL)
1030             return FALSE;
1031         }
1032
1033       application->priv->is_remote = application->priv->remote_actions != NULL;
1034       application->priv->is_registered = TRUE;
1035
1036       g_object_notify (G_OBJECT (application), "is-registered");
1037
1038       if (!application->priv->is_remote)
1039         {
1040           g_signal_emit (application, g_application_signals[SIGNAL_STARTUP], 0);
1041
1042           if (!application->priv->did_startup)
1043             g_critical ("GApplication subclass '%s' failed to chain up on"
1044                         " ::startup (from start of override function)",
1045                         G_OBJECT_TYPE_NAME (application));
1046         }
1047     }
1048
1049   return TRUE;
1050 }
1051
1052 /* Hold/release {{{1 */
1053 /**
1054  * g_application_hold:
1055  * @application: a #GApplication
1056  *
1057  * Increases the use count of @application.
1058  *
1059  * Use this function to indicate that the application has a reason to
1060  * continue to run.  For example, g_application_hold() is called by GTK+
1061  * when a toplevel window is on the screen.
1062  *
1063  * To cancel the hold, call g_application_release().
1064  **/
1065 void
1066 g_application_hold (GApplication *application)
1067 {
1068   if (application->priv->inactivity_timeout_id)
1069     {
1070       g_source_remove (application->priv->inactivity_timeout_id);
1071       application->priv->inactivity_timeout_id = 0;
1072     }
1073
1074   application->priv->use_count++;
1075 }
1076
1077 static gboolean
1078 inactivity_timeout_expired (gpointer data)
1079 {
1080   GApplication *application = G_APPLICATION (data);
1081
1082   application->priv->inactivity_timeout_id = 0;
1083
1084   return FALSE;
1085 }
1086
1087
1088 /**
1089  * g_application_release:
1090  * @application: a #GApplication
1091  *
1092  * Decrease the use count of @application.
1093  *
1094  * When the use count reaches zero, the application will stop running.
1095  *
1096  * Never call this function except to cancel the effect of a previous
1097  * call to g_application_hold().
1098  **/
1099 void
1100 g_application_release (GApplication *application)
1101 {
1102   application->priv->use_count--;
1103
1104   if (application->priv->use_count == 0 && application->priv->inactivity_timeout)
1105     application->priv->inactivity_timeout_id = g_timeout_add (application->priv->inactivity_timeout,
1106                                                               inactivity_timeout_expired, application);
1107 }
1108
1109 /* Activate, Open {{{1 */
1110 /**
1111  * g_application_activate:
1112  * @application: a #GApplication
1113  *
1114  * Activates the application.
1115  *
1116  * In essence, this results in the #GApplication::activate() signal being
1117  * emitted in the primary instance.
1118  *
1119  * The application must be registered before calling this function.
1120  *
1121  * Since: 2.28
1122  **/
1123 void
1124 g_application_activate (GApplication *application)
1125 {
1126   g_return_if_fail (G_IS_APPLICATION (application));
1127   g_return_if_fail (application->priv->is_registered);
1128
1129   if (application->priv->is_remote)
1130     g_application_impl_activate (application->priv->impl,
1131                                  get_platform_data (application));
1132
1133   else
1134     g_signal_emit (application, g_application_signals[SIGNAL_ACTIVATE], 0);
1135 }
1136
1137 /**
1138  * g_application_open:
1139  * @application: a #GApplication
1140  * @files: (array length=n_files): an array of #GFiles to open
1141  * @n_files: the length of the @files array
1142  * @hint: a hint (or ""), but never %NULL
1143  *
1144  * Opens the given files.
1145  *
1146  * In essence, this results in the #GApplication::open signal being emitted
1147  * in the primary instance.
1148  *
1149  * @n_files must be greater than zero.
1150  *
1151  * @hint is simply passed through to the ::open signal.  It is
1152  * intended to be used by applications that have multiple modes for
1153  * opening files (eg: "view" vs "edit", etc).  Unless you have a need
1154  * for this functionality, you should use "".
1155  *
1156  * The application must be registered before calling this function
1157  * and it must have the %G_APPLICATION_HANDLES_OPEN flag set.
1158  *
1159  * Since: 2.28
1160  **/
1161 void
1162 g_application_open (GApplication  *application,
1163                     GFile        **files,
1164                     gint           n_files,
1165                     const gchar   *hint)
1166 {
1167   g_return_if_fail (G_IS_APPLICATION (application));
1168   g_return_if_fail (application->priv->flags &
1169                     G_APPLICATION_HANDLES_OPEN);
1170   g_return_if_fail (application->priv->is_registered);
1171
1172   if (application->priv->is_remote)
1173     g_application_impl_open (application->priv->impl,
1174                              files, n_files, hint,
1175                              get_platform_data (application));
1176
1177   else
1178     g_signal_emit (application, g_application_signals[SIGNAL_OPEN],
1179                    0, files, n_files, hint);
1180 }
1181
1182 /* Run {{{1 */
1183 /**
1184  * g_application_run:
1185  * @application: a #GApplication
1186  * @argc: the argc from main() (or 0 if @argv is %NULL)
1187  * @argv: (array length=argc) (allow-none): the argv from main(), or %NULL
1188  *
1189  * Runs the application.
1190  *
1191  * This function is intended to be run from main() and its return value
1192  * is intended to be returned by main(). Although you are expected to pass
1193  * the @argc, @argv parameters from main() to this function, it is possible
1194  * to pass %NULL if @argv is not available or commandline handling is not
1195  * required.
1196  *
1197  * First, the local_command_line() virtual function is invoked.
1198  * This function always runs on the local instance. It gets passed a pointer
1199  * to a %NULL-terminated copy of @argv and is expected to remove the arguments
1200  * that it handled (shifting up remaining arguments). See
1201  * <xref linkend="gapplication-example-cmdline2"/> for an example of
1202  * parsing @argv manually. Alternatively, you may use the #GOptionContext API,
1203  * after setting <literal>argc = g_strv_length (argv);</literal>.
1204  *
1205  * The last argument to local_command_line() is a pointer to the @status
1206  * variable which can used to set the exit status that is returned from
1207  * g_application_run().
1208  *
1209  * If local_command_line() returns %TRUE, the command line is expected
1210  * to be completely handled, including possibly registering as the primary
1211  * instance, calling g_application_activate() or g_application_open(), etc.
1212  *
1213  * If local_command_line() returns %FALSE then the application is registered
1214  * and the #GApplication::command-line signal is emitted in the primary
1215  * instance (which may or may not be this instance). The signal handler
1216  * gets passed a #GApplicationCommandline object that (among other things)
1217  * contains the remaining commandline arguments that have not been handled
1218  * by local_command_line().
1219  *
1220  * If the application has the %G_APPLICATION_HANDLES_COMMAND_LINE
1221  * flag set then the default implementation of local_command_line()
1222  * always returns %FALSE immediately, resulting in the commandline
1223  * always being handled in the primary instance.
1224  *
1225  * Otherwise, the default implementation of local_command_line() tries
1226  * to do a couple of things that are probably reasonable for most
1227  * applications.  First, g_application_register() is called to attempt
1228  * to register the application.  If that works, then the command line
1229  * arguments are inspected.  If no commandline arguments are given, then
1230  * g_application_activate() is called.  If commandline arguments are
1231  * given and the %G_APPLICATION_HANDLES_OPEN flag is set then they
1232  * are assumed to be filenames and g_application_open() is called.
1233  *
1234  * If you need to handle commandline arguments that are not filenames,
1235  * and you don't mind commandline handling to happen in the primary
1236  * instance, you should set %G_APPLICATION_HANDLED_COMMAND_LINE and
1237  * process the commandline arguments in your #GApplication::command-line
1238  * signal handler, either manually or using the #GOptionContext API.
1239  *
1240  * If you are interested in doing more complicated local handling of the
1241  * commandline then you should implement your own #GApplication subclass
1242  * and override local_command_line(). In this case, you most likely want
1243  * to return %TRUE from your local_command_line() implementation to
1244  * suppress the default handling. See
1245  * <xref linkend="gapplication-example-cmdline2"/> for an example.
1246  *
1247  * If, after the above is done, the use count of the application is zero
1248  * then the exit status is returned immediately.  If the use count is
1249  * non-zero then the default main context is iterated until the use count
1250  * falls to zero, at which point 0 is returned.
1251  *
1252  * If the %G_APPLICATION_IS_SERVICE flag is set, then the exiting at
1253  * use count of zero is delayed for a while (ie: the instance stays
1254  * around to provide its <emphasis>service</emphasis> to others).
1255  *
1256  * Returns: the exit status
1257  *
1258  * Since: 2.28
1259  **/
1260 int
1261 g_application_run (GApplication  *application,
1262                    int            argc,
1263                    char         **argv)
1264 {
1265   gchar **arguments;
1266   int status;
1267   gint i;
1268
1269   g_return_val_if_fail (G_IS_APPLICATION (application), 1);
1270   g_return_val_if_fail (argc == 0 || argv != NULL, 1);
1271
1272   arguments = g_new (gchar *, argc + 1);
1273   for (i = 0; i < argc; i++)
1274     arguments[i] = g_strdup (argv[i]);
1275   arguments[i] = NULL;
1276
1277   if (g_get_prgname () == NULL && argc > 0)
1278     {
1279       gchar *prgname;
1280
1281       prgname = g_path_get_basename (argv[0]);
1282       g_set_prgname (prgname);
1283       g_free (prgname);
1284     }
1285
1286   if (!G_APPLICATION_GET_CLASS (application)
1287         ->local_command_line (application, &arguments, &status))
1288     {
1289       GError *error = NULL;
1290
1291       if (!g_application_register (application, NULL, &error))
1292         {
1293           g_printerr ("%s", error->message);
1294           g_error_free (error);
1295           return 1;
1296         }
1297
1298       if (application->priv->is_remote)
1299         {
1300           GVariant *platform_data;
1301
1302           platform_data = get_platform_data (application);
1303           status = g_application_impl_command_line (application->priv->impl,
1304                                                     arguments, platform_data);
1305         }
1306       else
1307         {
1308           GApplicationCommandLine *cmdline;
1309           GVariant *v;
1310
1311           v = g_variant_new_bytestring_array ((const gchar **) arguments, -1);
1312           cmdline = g_object_new (G_TYPE_APPLICATION_COMMAND_LINE,
1313                                   "arguments", v, NULL);
1314           g_signal_emit (application,
1315                          g_application_signals[SIGNAL_COMMAND_LINE],
1316                          0, cmdline, &status);
1317           g_object_unref (cmdline);
1318         }
1319     }
1320
1321   g_strfreev (arguments);
1322
1323   if (application->priv->flags & G_APPLICATION_IS_SERVICE &&
1324       application->priv->is_registered &&
1325       !application->priv->use_count &&
1326       !application->priv->inactivity_timeout_id)
1327     {
1328       application->priv->inactivity_timeout_id =
1329         g_timeout_add (10000, inactivity_timeout_expired, application);
1330     }
1331
1332   while (application->priv->use_count || application->priv->inactivity_timeout_id)
1333     {
1334       g_main_context_iteration (NULL, TRUE);
1335       status = 0;
1336     }
1337
1338   if (!application->priv->is_remote)
1339     {
1340       g_signal_emit (application, g_application_signals[SIGNAL_SHUTDOWN], 0);
1341
1342       if (!application->priv->did_shutdown)
1343         g_critical ("GApplication subclass '%s' failed to chain up on"
1344                     " ::shutdown (from end of override function)",
1345                     G_OBJECT_TYPE_NAME (application));
1346     }
1347
1348   if (application->priv->impl)
1349     g_application_impl_flush (application->priv->impl);
1350
1351   g_settings_sync ();
1352
1353   return status;
1354 }
1355
1356 static gchar **
1357 g_application_list_actions (GActionGroup *action_group)
1358 {
1359   GApplication *application = G_APPLICATION (action_group);
1360
1361   g_return_val_if_fail (application->priv->is_registered, NULL);
1362
1363   if (application->priv->remote_actions != NULL)
1364     return g_action_group_list_actions (application->priv->remote_actions);
1365
1366   else if (application->priv->actions != NULL)
1367     return g_action_group_list_actions (application->priv->actions);
1368
1369   else
1370     /* empty string array */
1371     return g_new0 (gchar *, 1);
1372 }
1373
1374 static gboolean
1375 g_application_query_action (GActionGroup        *group,
1376                             const gchar         *action_name,
1377                             gboolean            *enabled,
1378                             const GVariantType **parameter_type,
1379                             const GVariantType **state_type,
1380                             GVariant           **state_hint,
1381                             GVariant           **state)
1382 {
1383   GApplication *application = G_APPLICATION (group);
1384
1385   g_return_val_if_fail (application->priv->is_registered, FALSE);
1386
1387   if (application->priv->remote_actions != NULL)
1388     return g_action_group_query_action (application->priv->remote_actions,
1389                                         action_name,
1390                                         enabled,
1391                                         parameter_type,
1392                                         state_type,
1393                                         state_hint,
1394                                         state);
1395
1396   if (application->priv->actions != NULL)
1397     return g_action_group_query_action (application->priv->actions,
1398                                         action_name,
1399                                         enabled,
1400                                         parameter_type,
1401                                         state_type,
1402                                         state_hint,
1403                                         state);
1404
1405   return FALSE;
1406 }
1407
1408 static void
1409 g_application_change_action_state (GActionGroup *action_group,
1410                                    const gchar  *action_name,
1411                                    GVariant     *value)
1412 {
1413   GApplication *application = G_APPLICATION (action_group);
1414
1415   g_return_if_fail (application->priv->is_remote ||
1416                     application->priv->actions != NULL);
1417   g_return_if_fail (application->priv->is_registered);
1418
1419   if (application->priv->remote_actions)
1420     return g_action_group_change_action_state (application->priv->remote_actions, action_name, value);
1421
1422   else
1423     g_action_group_change_action_state (application->priv->actions,
1424                                         action_name, value);
1425 }
1426
1427 static void
1428 g_application_activate_action (GActionGroup *action_group,
1429                                const gchar  *action_name,
1430                                GVariant     *parameter)
1431 {
1432   GApplication *application = G_APPLICATION (action_group);
1433
1434   g_return_if_fail (application->priv->is_remote ||
1435                     application->priv->actions != NULL);
1436   g_return_if_fail (application->priv->is_registered);
1437
1438   if (application->priv->remote_actions)
1439     return g_action_group_change_action_state (application->priv->remote_actions, action_name, parameter);
1440
1441   else
1442     g_action_group_activate_action (application->priv->actions,
1443                                     action_name, parameter);
1444 }
1445
1446 static void
1447 g_application_action_group_iface_init (GActionGroupInterface *iface)
1448 {
1449   iface->list_actions = g_application_list_actions;
1450   iface->query_action = g_application_query_action;
1451   iface->change_action_state = g_application_change_action_state;
1452   iface->activate_action = g_application_activate_action;
1453 }
1454
1455 /* Default Application {{{1 */
1456
1457 static GApplication *default_app;
1458
1459 /**
1460  * g_application_get_default:
1461  * @returns: (transfer none): the default application for this process, or %NULL
1462  *
1463  * Returns the default #GApplication instance for this process.
1464  *
1465  * Normally there is only one #GApplication per process and it becomes
1466  * the default when it is created.  You can exercise more control over
1467  * this by using g_application_set_default().
1468  *
1469  * If there is no default application then %NULL is returned.
1470  *
1471  * Since: 2.32
1472  **/
1473 GApplication *
1474 g_application_get_default (void)
1475 {
1476   return default_app;
1477 }
1478
1479 /**
1480  * g_application_set_default:
1481  * @application: the application to set as default, or %NULL
1482  *
1483  * Sets or unsets the default application for the process, as returned
1484  * by g_application_get_default().
1485  *
1486  * This function does not take its own reference on @application.  If
1487  * @application is destroyed then the default application will revert
1488  * back to %NULL.
1489  *
1490  * Since: 2.32
1491  **/
1492 void
1493 g_application_set_default (GApplication *application)
1494 {
1495   default_app = application;
1496 }
1497
1498 /* Epilogue {{{1 */
1499 /* vim:set foldmethod=marker: */