factor-out common client-side code

Preparing for creating standalone client-side library.

4 files changed, 335 insertions, 568 deletions

diff --git a/gsettings/Makefile.am b/gsettings/Makefile.am
index 00795cb..c19a92f 100644
--- a/gsettings/Makefile.am
+++ b/gsettings/Makefile.am
@@ -1,13 +1,13 @@
-AM_CFLAGS = $(gio_CFLAGS) -I$(top_srcdir)/gvdb
+AM_CFLAGS = $(gio_CFLAGS) -I$(top_srcdir)
 
 giomodules_LTLIBRARIES = libdconfsettings.la
 
 libdconfsettings_la_LIBADD = $(gio_LIBS)
 libdconfsettings_la_LDFLAGS = -module -avoid-version -shared
 libdconfsettings_la_SOURCES = \
+	../client/dconf-client.h\
+	../client/dconf-client.c\
 	../gvdb/gvdb-reader.c	\
-	dconfdatabase.h		\
-	dconfdatabase.c		\
 	dconfsettingsbackend.c
 
 install-data-hook:
diff --git a/gsettings/dconfdatabase.c b/gsettings/dconfdatabase.c
deleted file mode 100644
index 44ce35a..0000000
--- a/gsettings/dconfdatabase.c
+++ /dev/null
@@ -1,489 +0,0 @@
-/*
- * Copyright © 2010 Codethink Limited
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the licence, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- *
- * Author: Ryan Lortie <desrt@desrt.ca>
- */
-
-#define G_SETTINGS_ENABLE_BACKEND
-#include <gio/gsettingsbackend.h>
-#include "dconfdatabase.h"
-
-#include <gio/gio.h>
-
-#include <string.h>
-#include "gvdb-reader.h"
-
-typedef struct _Outstanding Outstanding;
-
-struct _DConfDatabase
-{
-  GStaticMutex lock;
-
-  GDBusConnection *bus;
-  GvdbTable *value_table;
-  GSList *backends;
-  const gchar *context;
-
-  Outstanding *outstanding;
-  guint64 anti_expose;
-};
-
-struct _Outstanding
-{
-  Outstanding *next;
-
-  volatile guint32 serial;
-
-  gchar *reset_path, *set_key;
-  GVariant *set_value;
-
-  GTree *tree;
-};
-
-static volatile guint32 *
-dconf_database_new_outstanding (DConfDatabase *database,
-                                const gchar   *reset_path,
-                                const gchar   *set_key,
-                                GVariant      *set_value,
-                                GTree         *tree)
-{
-  Outstanding *outstanding;
-
-  outstanding = g_slice_new (Outstanding);
-  outstanding->serial = 0;
-  outstanding->reset_path = g_strdup (reset_path);
-  outstanding->set_key = g_strdup (set_key);
-
-  if (set_value)
-    outstanding->set_value = g_variant_ref_sink (set_value);
-  else
-    outstanding->set_value = NULL;
-
-  if (tree)
-    outstanding->tree = g_tree_ref (tree);
-  else
-    outstanding->tree = NULL;
-
-  g_static_mutex_lock (&database->lock);
-  outstanding->next = database->outstanding;
-  database->outstanding = outstanding;
-  g_static_mutex_unlock (&database->lock);
-
-  return &outstanding->serial;
-}
-
-static gboolean
-dconf_database_remove_outstanding (DConfDatabase *database,
-                                   GDBusMessage  *message,
-                                   guint64       *anti_expose)
-{
-  gboolean found = FALSE;
-  Outstanding **node;
-  guint32 serial;
-
-  if G_LIKELY (database->outstanding == NULL)
-    return FALSE;
-
-  serial = g_dbus_message_get_reply_serial (message);
-
-  if (serial == 0)
-    return FALSE;
-
-  g_static_mutex_lock (&database->lock);
-
-  /* this could be made more asymptotically efficient by using a queue
-   * or a double-linked list with a 'tail' pointer but the usual case
-   * here will be one outstanding item and very rarely more than a few.
-   *
-   * so we scan...
-   */
-  for (node = &database->outstanding; *node; node = &(*node)->next)
-    if ((*node)->serial == serial)
-      {
-        Outstanding *tmp;
-
-        tmp = *node;
-        *node = tmp->next;
-
-        g_static_mutex_unlock (&database->lock);
-
-        g_variant_get (g_dbus_message_get_body (message), "(t)", anti_expose);
-
-        g_free (tmp->reset_path);
-        g_free (tmp->set_key);
-
-        if (tmp->set_value)
-          g_variant_unref (tmp->set_value);
-
-        if (tmp->tree)
-          g_tree_unref (tmp->tree);
-
-        found = TRUE;
-        break;
-      }
-
-  g_static_mutex_unlock (&database->lock);
-
-  return found;
-}
-
-static gboolean
-dconf_database_scan_outstanding_tree (GTree       *tree,
-                                      const gchar *key,
-                                      gsize        key_length,
-                                      gpointer    *value)
-{
-  gchar *mykey;
-
-  mykey = g_alloca (key_length + 1);
-  memcpy (mykey, key, key_length + 1);
-
-  while (!g_tree_lookup_extended (tree, mykey, NULL, value) &&
-         --key_length)
-    {
-      while (mykey[key_length - 1] != '/')
-        key_length--;
-
-      mykey[key_length] = '\0';
-    }
-
-  return key_length != 0;
-}
-
-static gboolean
-dconf_database_scan_outstanding (DConfDatabase  *database,
-                                 const gchar    *key,
-                                 GVariant      **value)
-{
-  gboolean found = FALSE;
-  Outstanding *node;
-  gsize length;
-
-  length = strlen (key);
-
-  if G_LIKELY (database->outstanding == NULL)
-    return FALSE;
-
-  g_static_mutex_lock (&database->lock);
-
-  for (node = database->outstanding; node; node = node->next)
-    {
-      if (node->reset_path)
-        {
-          if (g_str_has_prefix (key, node->reset_path))
-            {
-              *value = NULL;
-              found = TRUE;
-              break;
-            }
-        }
-
-      else if (node->set_key)
-        {
-          if (strcmp (key, node->set_key) == 0)
-            {
-              if (node->set_value != NULL)
-                *value = g_variant_ref (node->set_value);
-              else
-                *value = NULL;
-
-              found = TRUE;
-              break;
-            }
-        }
-
-      else
-        {
-          gpointer result;
-
-          if (dconf_database_scan_outstanding_tree (node->tree, key,
-                                                    length, &result))
-            {
-              if (result)
-                *value = g_variant_ref (result);
-              else
-                *value = NULL;
-
-              found = TRUE;
-              break;
-            }
-        }
-    }
-
-  g_static_mutex_unlock (&database->lock);
-
-  return found;
-}
-
-static void
-dconf_database_reopen_file (DConfDatabase *database)
-{
-  gchar *filename;
-
-  if (database->value_table != NULL)
-    gvdb_table_unref (database->value_table);
-
-  filename = g_build_filename (g_get_user_config_dir (), "dconf", NULL);
-  database->value_table = gvdb_table_new (filename, FALSE, NULL);
-  g_free (filename);
-}
-
-GVariant *
-dconf_database_read (DConfDatabase *database,
-                     const gchar   *key)
-{
-  GVariant *value;
-
-  if (dconf_database_scan_outstanding (database, key, &value))
-    return value;
-
-  if (database->value_table == NULL)
-    return NULL;
-
-  dconf_database_reopen_file (database);
-
-  return gvdb_table_get_value (database->value_table, key, NULL);
-}
-
-static void
-dconf_database_incoming_signal (DConfDatabase *database,
-                                GDBusMessage  *message)
-{
-  const gchar **keys;
-  const gchar *name;
-  gboolean is_path;
-  guint64 serial;
-
-  if (strcmp (g_dbus_message_get_interface (message),
-              "ca.desrt.dconf.Writer") != 0 ||
-      strcmp (g_dbus_message_get_member (message), "Notify") != 0)
-    return;
-
-  g_variant_get (g_dbus_message_get_body (message),
-                 "(t&s^a&s)", &serial, &name, &keys);
-
-  is_path = g_str_has_suffix (name, "/");
-
-  if (serial != database->anti_expose)
-    {
-      GSList *node;
-
-      if (keys[0] == NULL)
-        {
-          for (node = database->backends; node; node = node->next)
-            if (is_path)
-              g_settings_backend_path_changed (node->data, name, NULL);
-            else
-              g_settings_backend_changed (node->data, name, NULL);
-        }
-      else if (is_path)
-        {
-          for (node = database->backends; node; node = node->next)
-            g_settings_backend_keys_changed (node->data, name, keys, NULL);
-        }
-    }
-
-  g_free (keys);
-}
-
-static gboolean
-dconf_database_filter_function (GDBusConnection *connection,
-                                GDBusMessage    *message,
-                                gpointer         user_data)
-{
-  DConfDatabase *database = user_data;
-
-  switch (g_dbus_message_get_message_type (message))
-    {
-    case G_DBUS_MESSAGE_TYPE_METHOD_RETURN:
-      return dconf_database_remove_outstanding (database, message,
-                                                &database->anti_expose);
-
-    case G_DBUS_MESSAGE_TYPE_SIGNAL:
-      dconf_database_incoming_signal (database, message);
-      return FALSE;
-
-    default:
-      return FALSE;
-    }
-}
-
-GVariant *
-fake_maybe (GVariant *value)
-{
-  GVariantBuilder builder;
-
-  g_variant_builder_init (&builder, G_VARIANT_TYPE ("av"));
-
-  if (value != NULL)
-    g_variant_builder_add (&builder, "v", value);
-
-  return g_variant_builder_end (&builder);
-}
-
-void
-dconf_database_write_tree (DConfDatabase  *database,
-                           GTree          *tree,
-                           gpointer        origin_tag)
-{
-  volatile guint32 *serial;
-  const gchar **keys;
-  GVariant **values;
-  gchar *path;
-
-  serial = dconf_database_new_outstanding (database, NULL, NULL, NULL, tree);
-  g_settings_backend_flatten_tree (tree, &path, &keys, &values);
-
-  {
-    GSList *node;
-
-    for (node = database->backends; node; node = node->next)
-      g_settings_backend_keys_changed (node->data, path,
-                                       keys, origin_tag);
-  }
-
-  {
-    GDBusMessage *message;
-    GVariantBuilder args;
-    gsize i;
-
-    message =
-      g_dbus_message_new_method_call ("ca.desrt.dconf", "/",
-                                      "ca.desrt.dconf.Writer", "Write");
-
-    g_variant_builder_init (&args, G_VARIANT_TYPE ("(sa(sav))"));
-    g_variant_builder_add (&args, "s", path);
-
-    g_variant_builder_open (&args, G_VARIANT_TYPE ("a(sav)"));
-    for (i = 0; keys[i]; i++)
-      g_variant_builder_add (&args, "(s@av)", keys[i], fake_maybe (values[i]));
-
-    g_variant_builder_close (&args);
-
-    g_dbus_message_set_body (message,
-                             g_variant_builder_end (&args));
-    g_dbus_connection_send_message (database->bus,
-                                    message, serial, NULL);
-    g_object_unref (message);
-  }
-
-  g_free (path);
-  g_free (keys);
-  g_free (values);
-}
-
-gchar **
-dconf_database_list (DConfDatabase *database,
-                     const gchar   *path,
-                     gsize         *length)
-{
-  gchar **result;
-
-  result = gvdb_table_list (database->value_table, path);
-
-  if (result)
-    *length = g_strv_length (result);
-
-  return result;
-}
-
-void
-dconf_database_write (DConfDatabase *database,
-                      const gchar   *path_or_key,
-                      GVariant      *value,
-                      gpointer       origin_tag)
-{
-  volatile guint32 *serial;
-  GDBusMessage *message;
-
-  serial = dconf_database_new_outstanding (database, NULL,
-                                           path_or_key, value,
-                                           NULL);
-
-  message = g_dbus_message_new_method_call ("ca.desrt.dconf", "/",
-                                            "ca.desrt.dconf.Writer", "Write");
-  g_dbus_message_set_body (message, g_variant_new ("(s@av)", path_or_key,
-                                                   fake_maybe (value)));
-  g_dbus_connection_send_message (database->bus, message, serial, NULL);
-  g_object_unref (message);
-
-  {
-    GSList *node;
-
-    for (node = database->backends; node; node = node->next)
-      g_settings_backend_changed (node->data, path_or_key, origin_tag);
-  }
-}
-
-static void
-send_match_rule (DConfDatabase *database,
-                 const gchar   *method,
-                 const gchar   *name)
-{
-  GDBusMessage *message;
-  gchar *rule;
-
-  rule = g_strdup_printf ("interface='ca.desrt.dconf.Writer',"
-                          "arg1path='%s'", name);
-  message = g_dbus_message_new_method_call ("org.freedesktop.DBus", "/",
-                                            "org.freedesktop.DBus", method);
-  g_dbus_message_set_body (message, g_variant_new ("(s)", (rule)));
-  g_dbus_message_set_flags (message, G_DBUS_MESSAGE_FLAGS_NO_REPLY_EXPECTED);
-  g_dbus_connection_send_message (database->bus, message, NULL, NULL);
-  g_object_unref (message);
-  g_free (rule);
-}
-
-void
-dconf_database_subscribe (DConfDatabase *database,
-                          const gchar   *name)
-{
-  send_match_rule (database, "AddMatch", name);
-}
-
-void
-dconf_database_unsubscribe (DConfDatabase *database,
-                            const gchar   *name)
-{
-  send_match_rule (database, "RemoveMatch", name);
-}
-
-DConfDatabase *
-dconf_database_get_for_backend (gpointer backend)
-{
-  static gsize instance;
-
-  if (g_once_init_enter (&instance))
-    {
-      DConfDatabase *database;
-
-      database = g_slice_new0 (DConfDatabase);
-      g_static_mutex_init (&database->lock);
-      database->outstanding = NULL;
-      database->backends = g_slist_prepend (database->backends, backend);
-      database->bus = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, NULL);
-      g_dbus_connection_add_filter (database->bus,
-                                    dconf_database_filter_function,
-                                    database, NULL);
-      dconf_database_reopen_file (database);
-
-      g_once_init_leave (&instance, (gsize) database);
-    }
-
-  return (DConfDatabase *) instance;
-}
diff --git a/gsettings/dconfdatabase.h b/gsettings/dconfdatabase.h
deleted file mode 100644
index 8e0586d..0000000
--- a/gsettings/dconfdatabase.h
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright © 2010 Codethink Limited
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the licence, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- *
- * Author: Ryan Lortie <desrt@desrt.ca>
- */
-
-#ifndef _dconfdatabase_h_
-#define _dconfdatabase_h_
-
-#include <glib.h>
-
-typedef struct _DConfDatabase DConfDatabase;
-
-G_GNUC_INTERNAL
-DConfDatabase * dconf_database_get_for_backend  (gpointer       backend);
-
-G_GNUC_INTERNAL
-GVariant *      dconf_database_read             (DConfDatabase *database,
-                                                 const gchar   *key);
-G_GNUC_INTERNAL
-gchar **        dconf_database_list             (DConfDatabase *database,
-                                                 const gchar   *path,
-                                                 gsize         *length);
-G_GNUC_INTERNAL
-void            dconf_database_write            (DConfDatabase *database,
-                                                 const gchar   *path_or_key,
-                                                 GVariant      *value,
-                                                 gpointer       origin_tag);
-G_GNUC_INTERNAL
-void            dconf_database_write_tree       (DConfDatabase *database,
-                                                 GTree         *tree,
-                                                 gpointer       origin_tag);
-G_GNUC_INTERNAL
-void            dconf_database_subscribe        (DConfDatabase *database,
-                                                 const gchar   *name);
-G_GNUC_INTERNAL
-void            dconf_database_unsubscribe      (DConfDatabase *database,
-                                                 const gchar   *name);
-
-#endif
diff --git a/gsettings/dconfsettingsbackend.c b/gsettings/dconfsettingsbackend.c
index d5ef40d..0c49865 100644
--- a/gsettings/dconfsettingsbackend.c
+++ b/gsettings/dconfsettingsbackend.c
@@ -21,23 +21,226 @@
 
 #define G_SETTINGS_ENABLE_BACKEND
 #include <gio/gsettingsbackend.h>
+#include <client/dconf-client.h>
 #include <gio/gio.h>
 
-#include "dconfdatabase.h"
+#include <string.h>
 
 typedef GSettingsBackendClass DConfSettingsBackendClass;
+typedef struct _Outstanding Outstanding;
 
 typedef struct
 {
   GSettingsBackend backend;
+  GStaticMutex lock;
 
-  DConfDatabase *database;
+  DConfClient *client;
+
+  Outstanding *outstanding;
+  GDBusConnection *bus;
+  guint64 anti_expose;
 } DConfSettingsBackend;
 
 G_DEFINE_TYPE (DConfSettingsBackend,
                dconf_settings_backend,
                G_TYPE_SETTINGS_BACKEND)
 
+
+struct _Outstanding
+{
+  Outstanding *next;
+
+  volatile guint32 serial;
+
+  gchar *reset_path, *set_key;
+  GVariant *set_value;
+
+  GTree *tree;
+};
+
+static volatile guint32 *
+dconf_settings_backend_new_outstanding (DConfSettingsBackend *dcsb,
+                                        const gchar          *set_key,
+                                        GVariant             *set_value,
+                                        GTree                *tree)
+{
+  Outstanding *outstanding;
+
+  outstanding = g_slice_new (Outstanding);
+  outstanding->reset_path = NULL;
+  outstanding->set_key = NULL;
+
+  if (!set_key || g_str_has_suffix (set_key, "/"))
+    {
+      g_assert (set_value == NULL);
+      outstanding->reset_path = g_strdup (set_key);
+    }
+  else
+    outstanding->set_key = g_strdup (set_key);
+
+  outstanding->serial = 0;
+
+  if (set_value)
+    outstanding->set_value = g_variant_ref_sink (set_value);
+  else
+    outstanding->set_value = NULL;
+
+  if (tree)
+    outstanding->tree = g_tree_ref (tree);
+  else
+    outstanding->tree = NULL;
+
+  g_static_mutex_lock (&dcsb->lock);
+  outstanding->next = dcsb->outstanding;
+  dcsb->outstanding = outstanding;
+  g_static_mutex_unlock (&dcsb->lock);
+
+  return &outstanding->serial;
+}
+
+static gboolean
+dconf_settings_backend_remove_outstanding (DConfSettingsBackend *dcsb,
+                                           GDBusMessage         *message,
+                                           guint64              *anti_expose)
+{
+  gboolean found = FALSE;
+  Outstanding **node;
+  guint32 serial;
+
+  if G_LIKELY (dcsb->outstanding == NULL)
+    return FALSE;
+
+  serial = g_dbus_message_get_reply_serial (message);
+
+  if (serial == 0)
+    return FALSE;
+
+  g_static_mutex_lock (&dcsb->lock);
+
+  /* this could be made more asymptotically efficient by using a queue
+   * or a double-linked list with a 'tail' pointer but the usual case
+   * here will be one outstanding item and very rarely more than a few.
+   *
+   * so we scan...
+   */
+  for (node = &dcsb->outstanding; *node; node = &(*node)->next)
+    if ((*node)->serial == serial)
+      {
+        Outstanding *tmp;
+
+        tmp = *node;
+        *node = tmp->next;
+
+        g_static_mutex_unlock (&dcsb->lock);
+
+        g_variant_get (g_dbus_message_get_body (message), "(t)", anti_expose);
+
+        g_free (tmp->reset_path);
+        g_free (tmp->set_key);
+
+        if (tmp->set_value)
+          g_variant_unref (tmp->set_value);
+
+        if (tmp->tree)
+          g_tree_unref (tmp->tree);
+
+        found = TRUE;
+        break;
+      }
+
+  g_static_mutex_unlock (&dcsb->lock);
+
+  return found;
+}
+
+static gboolean
+dconf_settings_backend_scan_outstanding_tree (GTree       *tree,
+                                              const gchar *key,
+                                              gsize        key_length,
+                                              gpointer    *value)
+{
+  gchar *mykey;
+
+  mykey = g_alloca (key_length + 1);
+  memcpy (mykey, key, key_length + 1);
+
+  while (!g_tree_lookup_extended (tree, mykey, NULL, value) &&
+         --key_length)
+    {
+      while (mykey[key_length - 1] != '/')
+        key_length--;
+
+      mykey[key_length] = '\0';
+    }
+
+  return key_length != 0;
+}
+
+static gboolean
+dconf_settings_backend_scan_outstanding (DConfSettingsBackend  *backend,
+                                         const gchar           *key,
+                                         GVariant             **value)
+{
+  gboolean found = FALSE;
+  Outstanding *node;
+  gsize length;
+
+  length = strlen (key);
+
+  if G_LIKELY (backend->outstanding == NULL)
+    return FALSE;
+
+  g_static_mutex_lock (&backend->lock);
+
+  for (node = backend->outstanding; node; node = node->next)
+    {
+      if (node->reset_path)
+        {
+          if (g_str_has_prefix (key, node->reset_path))
+            {
+              *value = NULL;
+              found = TRUE;
+              break;
+            }
+        }
+
+      else if (node->set_key)
+        {
+          if (strcmp (key, node->set_key) == 0)
+            {
+              if (node->set_value != NULL)
+                *value = g_variant_ref (node->set_value);
+              else
+                *value = NULL;
+
+              found = TRUE;
+              break;
+            }
+        }
+
+      else
+        {
+          gpointer result;
+
+          if (dconf_settings_backend_scan_outstanding_tree (node->tree, key,
+                                                    length, &result))
+            {
+              if (result)
+                *value = g_variant_ref (result);
+              else
+                *value = NULL;
+
+              found = TRUE;
+              break;
+            }
+        }
+    }
+
+  g_static_mutex_unlock (&backend->lock);
+
+  return found;
+}
+
 static GVariant *
 dconf_settings_backend_read (GSettingsBackend   *backend,
                              const gchar        *key,
@@ -45,21 +248,68 @@ dconf_settings_backend_read (GSettingsBackend   *backend,
                              gboolean            default_value)
 {
   DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  DConfClientReadType type;
+
+  if (!default_value)
+    {
+      GVariant *value;
 
-  if (default_value)
-    return NULL;
+      if (dconf_settings_backend_scan_outstanding (dcsb, key, &value))
+        return value;
 
-  return dconf_database_read (dcsb->database, key);
+      type = DCONF_CLIENT_READ_NORMAL;
+    }
+  else
+    type = DCONF_CLIENT_READ_RESET;
+
+  return dconf_client_read (dcsb->client, key, expected_type, type);
 }
 
-static gchar **
-dconf_settings_backend_list (GSettingsBackend   *backend,
-                             const gchar        *path,
-                             gsize              *length)
+static void
+dconf_settings_backend_send (GDBusConnection    *bus,
+                             DConfClientMessage *dccm,
+                             volatile guint32   *serial)
 {
-  DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  GDBusMessage *message;
+
+  message = g_dbus_message_new_method_call (dccm->destination,
+                                            dccm->object_path,
+                                            dccm->interface,
+                                            dccm->method);
+  g_dbus_message_set_body (message, dccm->body);
+
+  if (serial)
+    g_dbus_connection_send_message (bus, message, serial, NULL);
+  else
+    g_dbus_connection_send_message_with_reply_sync (bus, message, -1,
+                                                    NULL, NULL, NULL);
+
+  g_variant_unref (dccm->body);
+  g_object_unref (message);
+}
+
+static gboolean
+dconf_settings_backend_get_bus (GDBusConnection    **bus,
+                                DConfClientMessage  *dccm)
+{
+  switch (dccm->bus_type)
+    {
+    case 'e':
+      *bus = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, NULL);
+      break;
+
+    case 'y':
+      *bus = g_bus_get_sync (G_BUS_TYPE_SYSTEM, NULL, NULL);
+      break;
 
-  return dconf_database_list (dcsb->database, path, length);
+    default:
+      g_assert_not_reached ();
+    }
+
+  if (*bus == NULL && dccm->body)
+    g_variant_unref (dccm->body);
+
+  return *bus != NULL;
 }
 
 static gboolean
@@ -69,8 +319,27 @@ dconf_settings_backend_write (GSettingsBackend *backend,
                               gpointer          origin_tag)
 {
   DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  DConfClientMessage message;
+  volatile guint32 *serial;
+  GDBusConnection *bus;
+
+  if (!dconf_client_write (dcsb->client, &message, path_or_key, value))
+    return FALSE;
 
-  dconf_database_write (dcsb->database, path_or_key, value, origin_tag);
+  if (!dconf_settings_backend_get_bus (&bus, &message))
+    return FALSE;
+
+  serial = dconf_settings_backend_new_outstanding (dcsb,
+                                                   path_or_key,
+                                                   value,
+                                                   NULL);
+
+  dconf_settings_backend_send (bus, &message, serial);
+
+  if (g_str_has_suffix (path_or_key, "/"))
+    g_settings_backend_changed_path (backend, path_or_key, origin_tag);
+  else
+    g_settings_backend_changed (backend, path_or_key, origin_tag);
 
   return TRUE;
 }
@@ -81,10 +350,35 @@ dconf_settings_backend_write_tree (GSettingsBackend *backend,
                                    gpointer          origin_tag)
 {
   DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  DConfClientMessage message;
+  volatile guint32 *serial;
+  GDBusConnection *bus;
+  const gchar **keys;
+  GVariant **values;
+  gchar *prefix;
 
-  dconf_database_write_tree (dcsb->database, tree, origin_tag);
+  g_settings_backend_flatten_tree (tree, &prefix, &keys, &values);
 
-  return TRUE;
+  if (dconf_client_write_many (dcsb->client, &message, prefix, keys, values))
+    {
+      if (dconf_settings_backend_get_bus (&bus, &message))
+        {
+          serial = dconf_settings_backend_new_outstanding (dcsb, NULL,
+                                                           NULL, tree);
+
+          dconf_settings_backend_send (bus, &message, serial);
+
+          g_settings_backend_keys_changed (backend, prefix, keys, origin_tag);
+
+          return TRUE;
+        }
+    }
+
+  g_free (prefix);
+  g_free (values);
+  g_free (keys);
+
+  return FALSE;
 }
 
 static void
@@ -92,14 +386,21 @@ dconf_settings_backend_reset (GSettingsBackend *backend,
                               const gchar      *path_or_key,
                               gpointer          origin_tag)
 {
-  dconf_settings_backend_write (backend, path_or_key, NULL, origin_tag);
+  g_assert_not_reached ();
 }
 
 static gboolean
 dconf_settings_backend_get_writable (GSettingsBackend *backend,
-                                     const gchar      *key)
+                                     const gchar      *name)
 {
-  return TRUE;
+  DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  DConfClientMessage message;
+  GDBusConnection *bus;
+
+  if (!dconf_client_is_writable (dcsb->client, &message, name))
+    return FALSE;
+
+  return dconf_settings_backend_get_bus (&bus, &message);
 }
 
 static void
@@ -107,8 +408,13 @@ dconf_settings_backend_subscribe (GSettingsBackend *backend,
                                   const gchar      *name)
 {
   DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  DConfClientMessage message;
+  GDBusConnection *bus;
 
-  dconf_database_subscribe (dcsb->database, name);
+  dconf_client_watch (dcsb->client, &message, name);
+
+  if (dconf_settings_backend_get_bus (&bus, &message))
+    dconf_settings_backend_send (bus, &message, NULL);
 }
 
 static void
@@ -116,8 +422,13 @@ dconf_settings_backend_unsubscribe (GSettingsBackend *backend,
                                     const gchar      *name)
 {
   DConfSettingsBackend *dcsb = (DConfSettingsBackend *) backend;
+  DConfClientMessage message;
+  GDBusConnection *bus;
+
+  dconf_client_unwatch (dcsb->client, &message, name);
 
-  dconf_database_unsubscribe (dcsb->database, name);
+  if (dconf_settings_backend_get_bus (&bus, &message))
+    dconf_settings_backend_send (bus, &message, NULL);
 }
 
 static void
@@ -128,14 +439,14 @@ dconf_settings_backend_sync (GSettingsBackend *backend)
 static void
 dconf_settings_backend_init (DConfSettingsBackend *dcsb)
 {
-  dcsb->database = dconf_database_get_for_backend (dcsb);
+  dcsb->client = dconf_client_new (NULL);
 }
 
 static void
 dconf_settings_backend_class_init (GSettingsBackendClass *class)
 {
   class->read = dconf_settings_backend_read;
-  class->list = dconf_settings_backend_list;
+  // class->list = dconf_settings_backend_list;
   class->write = dconf_settings_backend_write;
   class->write_keys = dconf_settings_backend_write_tree;
   class->reset = dconf_settings_backend_reset;