gapplication: add GApplication:version property

This property is supposed to be used by authors of applications that use GAppliaction to output the version by --version flag or otherwise if a version is needed.

Closes #3198

Signed-off-by: Maxim Moskalets <Maxim.Moskalets@kaspersky.com>

gio/gapplication.c

@@ -227,6 +227,7 @@ struct _GApplicationPrivate
 {
   GApplicationFlags  flags;
   gchar             *id;
+  gchar             *version;
   gchar             *resource_path;
 
   GActionGroup      *actions;
@@ -264,6 +265,7 @@ enum
 {
   PROP_NONE,
   PROP_APPLICATION_ID,
+  PROP_VERSION,
   PROP_FLAGS,
   PROP_RESOURCE_BASE_PATH,
   PROP_IS_REGISTERED,
@@ -478,11 +480,13 @@ g_application_pack_option_entries (GApplication *application,
 static GVariantDict *
 g_application_parse_command_line (GApplication   *application,
                                   gchar        ***arguments,
+                                  gboolean       *print_version,
                                   GError        **error)
 {
   gboolean become_service = FALSE;
   gchar *app_id = NULL;
   gboolean replace = FALSE;
+  gboolean version = FALSE;
   GVariantDict *dict = NULL;
   GOptionContext *context;
   GOptionGroup *gapplication_group;
@@ -564,6 +568,17 @@ g_application_parse_command_line (GApplication   *application,
       g_option_group_add_entries (gapplication_group, entries);
     }
 
+  if (application->priv->version)
+    {
+      GOptionEntry entries[] = {
+        { "version", '\0', 0, G_OPTION_ARG_NONE, &version,
+          N_("Print the application version"), NULL },
+        G_OPTION_ENTRY_NULL
+      };
+
+      g_option_group_add_entries (gapplication_group, entries);
+    }
+
   /* Allow replacing if the application allows it */
   if (application->priv->flags & G_APPLICATION_ALLOW_REPLACEMENT)
     {
@@ -580,6 +595,8 @@ g_application_parse_command_line (GApplication   *application,
   if (!g_option_context_parse_strv (context, arguments, error))
     goto out;
 
+  *print_version = version;
+
   /* Check for --gapplication-service */
   if (become_service)
     application->priv->flags |= G_APPLICATION_IS_SERVICE;
@@ -1101,8 +1118,9 @@ g_application_real_local_command_line (GApplication   *application,
   GError *error = NULL;
   GVariantDict *options;
   gint n_args;
+  gboolean print_version = FALSE;
 
-  options = g_application_parse_command_line (application, arguments, &error);
+  options = g_application_parse_command_line (application, arguments, &print_version, &error);
   if (!options)
     {
       g_printerr ("%s\n", error->message);
@@ -1111,6 +1129,21 @@ g_application_real_local_command_line (GApplication   *application,
       return TRUE;
     }
 
+  /* Exit quickly with --version? */
+  if (print_version)
+    {
+      const char *prgname = g_get_prgname ();
+
+      g_assert (application->priv->version != NULL);
+
+      if (prgname != NULL)
+        g_print ("%s %s\n", prgname, application->priv->version);
+      else
+        g_print ("%s\n", application->priv->version);
+      *exit_status = EXIT_SUCCESS;
+      return TRUE;
+    }
+
   g_signal_emit (application, g_application_signals[SIGNAL_HANDLE_LOCAL_OPTIONS], 0, options, exit_status);
 
   if (*exit_status >= 0)
@@ -1236,6 +1269,10 @@ g_application_set_property (GObject      *object,
                                         g_value_get_string (value));
       break;
 
+    case PROP_VERSION:
+      g_application_set_version (application, g_value_get_string (value));
+      break;
+
     case PROP_FLAGS:
       g_application_set_flags (application, g_value_get_flags (value));
       break;
@@ -1306,6 +1343,11 @@ g_application_get_property (GObject    *object,
                           g_application_get_application_id (application));
       break;
 
+    case PROP_VERSION:
+      g_value_set_string (value,
+                          g_application_get_version (application));
+      break;
+
     case PROP_FLAGS:
       g_value_set_flags (value,
                          g_application_get_flags (application));
@@ -1401,6 +1443,7 @@ g_application_finalize (GObject *object)
   g_free (application->priv->parameter_string);
   g_free (application->priv->summary);
   g_free (application->priv->description);
+  g_free (application->priv->version);
 
   g_slist_free_full (application->priv->option_strings, g_free);
 
@@ -1496,6 +1539,18 @@ g_application_class_init (GApplicationClass *class)
                          NULL, G_PARAM_READWRITE | G_PARAM_CONSTRUCT |
                          G_PARAM_STATIC_STRINGS));
 
+  /**
+   * GApplication:version:
+   *
+   * The human-readable version number of the application.
+   *
+   * Since: 2.80
+   */
+  g_object_class_install_property (object_class, PROP_VERSION,
+    g_param_spec_string ("version", NULL, NULL,
+                         NULL, G_PARAM_READWRITE |
+                         G_PARAM_STATIC_STRINGS | G_PARAM_EXPLICIT_NOTIFY));
+
   /**
    * GApplication:flags:
    *
@@ -1887,6 +1942,50 @@ g_application_set_application_id (GApplication *application,
     }
 }
 
+/**
+ * g_application_get_version:
+ * @application: a #GApplication
+ *
+ * Gets the version of @application.
+ *
+ * Returns: (nullable): the version of @application
+ *
+ * Since: 2.80
+ **/
+const gchar *
+g_application_get_version (GApplication *application)
+{
+  g_return_val_if_fail (G_IS_APPLICATION (application), NULL);
+
+  return application->priv->version;
+}
+
+/**
+ * g_application_set_version
+ * @application: a #GApplication
+ * @version: the version of @application
+ *
+ * Sets the version number of @application. This will be used to implement
+ * a `--version` command line argument
+ *
+ * The application version can only be modified if @application has not yet
+ * been registered.
+ *
+ * Since: 2.80
+ **/
+void
+g_application_set_version (GApplication *application,
+                           const gchar  *version)
+{
+  g_return_if_fail (G_IS_APPLICATION (application));
+  g_return_if_fail (version != NULL);
+  g_return_if_fail (!application->priv->is_registered);
+
+  if (g_set_str (&application->priv->version, version))
+    g_object_notify (G_OBJECT (application), "version");
+}
+
+
 /**
  * g_application_get_flags:
  * @application: a #GApplication

gio/gapplication.h

@@ -139,6 +139,12 @@ GIO_AVAILABLE_IN_ALL
 void                    g_application_set_application_id                (GApplication             *application,
                                                                          const gchar              *application_id);
 
+GIO_AVAILABLE_IN_2_80
+const gchar *           g_application_get_version                       (GApplication             *application);
+GIO_AVAILABLE_IN_2_80
+void                    g_application_set_version                       (GApplication             *application,
+                                                                         const gchar              *version);
+
 GIO_AVAILABLE_IN_2_34
 GDBusConnection *       g_application_get_dbus_connection               (GApplication             *application);
 GIO_AVAILABLE_IN_2_34

gio/tests/gapplication-example-cmdline.c

@@ -34,6 +34,7 @@ main (int argc, char **argv)
                            G_APPLICATION_HANDLES_COMMAND_LINE);
   g_signal_connect (app, "command-line", G_CALLBACK (command_line), NULL);
   g_application_set_inactivity_timeout (app, 10000);
+  g_application_set_version (app, "2.3");
 
   status = g_application_run (app, argc, argv);
 

gio/tests/gapplication.c

@@ -369,6 +369,7 @@ properties (void)
   GDBusConnection *c;
   GObject *app;
   gchar *id;
+  gchar *version;
   GApplicationFlags flags;
   gboolean registered;
   guint timeout;
@@ -381,20 +382,25 @@ properties (void)
 
   app = g_object_new (G_TYPE_APPLICATION,
                       "application-id", "org.gtk.TestApplication",
+                      "version", "1.0",
                       NULL);
 
   g_object_get (app,
                 "application-id", &id,
+                "version", &version,
                 "flags", &flags,
                 "is-registered", &registered,
                 "inactivity-timeout", &timeout,
                 NULL);
 
   g_assert_cmpstr (id, ==, "org.gtk.TestApplication");
+  g_assert_cmpstr (version, ==, "1.0");
   g_assert_cmpint (flags, ==, G_APPLICATION_DEFAULT_FLAGS);
   g_assert (!registered);
   g_assert_cmpint (timeout, ==, 0);
 
+  g_clear_pointer (&version, g_free);
+
   ret = g_application_register (G_APPLICATION (app), NULL, &error);
   g_assert (ret);
   g_assert_no_error (error);
@@ -1085,6 +1091,37 @@ test_api (void)
   g_object_unref (app);
 }
 
+static void
+test_version (void)
+{
+  GApplication *app;
+  gchar *version = NULL;
+  gchar *version_orig = NULL;
+
+  app = g_application_new ("org.gtk.TestApplication", 0);
+
+  version_orig = "1.2";
+  g_object_set (G_OBJECT (app), "version", version_orig, NULL);
+  g_object_get (app, "version", &version, NULL);
+  g_assert_cmpstr (version, ==, version_orig);
+  g_free (version);
+
+  /* test attempting to set the same version again */
+  version_orig = "1.2";
+  g_object_set (G_OBJECT (app), "version", version_orig, NULL);
+  g_object_get (app, "version", &version, NULL);
+  g_assert_cmpstr (version, ==, version_orig);
+  g_free (version);
+
+  version_orig = "2.4";
+  g_object_set (G_OBJECT (app), "version", version_orig, NULL);
+  g_object_get (app, "version", &version, NULL);
+  g_assert_cmpstr (version, ==, version_orig);
+  g_free (version);
+
+  g_object_unref (app);
+}
+
 /* Check that G_APPLICATION_ALLOW_REPLACEMENT works. To do so, we launch
  * a GApplication in this process that allows replacement, and then
  * launch a subprocess with --gapplication-replace. We have to do our
@@ -1830,6 +1867,7 @@ main (int argc, char **argv)
   g_test_add_func ("/gapplication/test-handle-local-options2", test_handle_local_options_failure);
   g_test_add_func ("/gapplication/test-handle-local-options3", test_handle_local_options_passthrough);
   g_test_add_func ("/gapplication/api", test_api);
+  g_test_add_func ("/gapplication/version", test_version);
   g_test_add_data_func ("/gapplication/replace", GINT_TO_POINTER (TRUE), test_replace);
   g_test_add_data_func ("/gapplication/no-replace", GINT_TO_POINTER (FALSE), test_replace);
   g_test_add_func ("/gapplication/dbus/activate", test_dbus_activate);