gio/gnullsettingsbackend.c

   1 /*
   2  * Copyright © 2010 Codethink Limited
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the licence, or (at 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 Public
  15  * 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  * Author: Ryan Lortie <desrt@desrt.ca>
  20  */
  21
  22 #include "config.h"
  23
  24 #include "gsettingsbackendinternal.h"
  25 #include "giomodule.h"
  26 #include "gsimplepermission.h"
  27
  28
  29 #define G_TYPE_NULL_SETTINGS_BACKEND    (g_null_settings_backend_get_type ())
  30 #define G_NULL_SETTINGS_BACKEND(inst)   (G_TYPE_CHECK_INSTANCE_CAST ((inst), \
  31                                          G_TYPE_NULL_SETTINGS_BACKEND,       \
  32                                          GNullSettingsBackend))
  33
  34
  35 typedef GSettingsBackendClass GNullSettingsBackendClass;
  36 typedef GSettingsBackend      GNullSettingsBackend;
  37
  38 G_DEFINE_TYPE_WITH_CODE (GNullSettingsBackend,
  39                          g_null_settings_backend,
  40                          G_TYPE_SETTINGS_BACKEND,
  41                          g_io_extension_point_implement (G_SETTINGS_BACKEND_EXTENSION_POINT_NAME,
  42                                                          g_define_type_id, "null", 10))
  43
  44 static GVariant *
  45 g_null_settings_backend_read (GSettingsBackend   *backend,
  46                               const gchar        *key,
  47                               const GVariantType *expected_type,
  48                               gboolean            default_value)
  49 {
  50   return NULL;
  51 }
  52
  53 static gboolean
  54 g_null_settings_backend_write (GSettingsBackend *backend,
  55                                const gchar      *key,
  56                                GVariant         *value,
  57                                gpointer          origin_tag)
  58 {
  59   return FALSE;
  60 }
  61
  62 static gboolean
  63 g_null_settings_backend_write_tree (GSettingsBackend *backend,
  64                                     GTree            *tree,
  65                                     gpointer          origin_tag)
  66 {
  67   return FALSE;
  68 }
  69
  70 static void
  71 g_null_settings_backend_reset (GSettingsBackend *backend,
  72                                const gchar      *key,
  73                                gpointer          origin_tag)
  74 {
  75 }
  76
  77 static gboolean
  78 g_null_settings_backend_get_writable (GSettingsBackend *backend,
  79                                       const gchar      *name)
  80 {
  81   return FALSE;
  82 }
  83
  84 static GPermission *
  85 g_null_settings_backend_get_permission (GSettingsBackend *backend,
  86                                         const gchar      *path)
  87 {
  88   return g_simple_permission_new (FALSE);
  89 }
  90
  91 static void
  92 g_null_settings_backend_init (GNullSettingsBackend *memory)
  93 {
  94 }
  95
  96 static void
  97 g_null_settings_backend_class_init (GNullSettingsBackendClass *class)
  98 {
  99   GSettingsBackendClass *backend_class = G_SETTINGS_BACKEND_CLASS (class);
 100
 101   backend_class->read = g_null_settings_backend_read;
 102   backend_class->write = g_null_settings_backend_write;
 103   backend_class->write_tree = g_null_settings_backend_write_tree;
 104   backend_class->reset = g_null_settings_backend_reset;
 105   backend_class->get_writable = g_null_settings_backend_get_writable;
 106   backend_class->get_permission = g_null_settings_backend_get_permission;
 107 }
 108
 109 GSettingsBackend *
 110 g_null_settings_backend_new (void)
 111 {
 112   return g_object_new (G_TYPE_NULL_SETTINGS_BACKEND, NULL);
 113 }