Merge branch 'start-refactor' into 'main'

Start refactoring into marshalers and translators

See merge request GNOME/at-spi2-core!98

22 files changed, 628 insertions, 317 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 962946a1..740bc14d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -59,15 +59,18 @@ opensuse-x86_64:
     - meson install -C _build
     - mkdir /tmp/test+dir+with+funny+chars
     - export XDG_RUNTIME_DIR=/tmp/test+dir+with+funny+chars # See https://gitlab.gnome.org/GNOME/at-spi2-core/-/issues/48
+    - dbus-run-session -- ci/run-registryd-tests.sh
     - dbus-run-session -- ci/run-tests.sh
   artifacts:
     reports:
-      junit: "_build/meson-logs/testlog.junit.xml"
+      junit:
+        - "_build/meson-logs/testlog.junit.xml"
+        - "_build/tests/registryd/registryd-pytest.junit.xml"
     when: always
     name: "at-spi2-core-${CI_COMMIT_REF_NAME}"
     paths:
-      - "${CI_PROJECT_DIR}/_build/meson-logs"
-      - "${CI_PROJECT_DIR}/_build/atspi/Atspi-2.0.gir"
+      - "_build/meson-logs"
+      - "_build/tests/registryd"
 
 fedora-x86_64:
   stage: build
@@ -87,8 +90,7 @@ fedora-x86_64:
     when: always
     name: "at-spi2-core-${CI_COMMIT_REF_NAME}"
     paths:
-      - "${CI_PROJECT_DIR}/_build/meson-logs"
-      - "${CI_PROJECT_DIR}/_build/atspi/Atspi-2.0.gir"
+      - "_build/meson-logs"
 
 # Run static analysis on the code.
 #
@@ -153,6 +155,7 @@ coverage:
     - meson setup ${MESON_EXTRA_FLAGS} --prefix /usr _build .
     - meson compile -C _build
     - meson install -C _build
+    - dbus-run-session -- ci/run-registryd-tests.sh
     - dbus-run-session -- ci/run-tests.sh
     - mkdir -p public
     - grcov _build --source-dir ./ --prefix-dir ../ --output-type cobertura --branch --ignore-not-existing -o coverage.xml
diff --git a/atspi/atspi-accessible.c b/atspi/atspi-accessible.c
index 26cf0ba7..9c4725a4 100644
--- a/atspi/atspi-accessible.c
+++ b/atspi/atspi-accessible.c
@@ -424,7 +424,7 @@ atspi_accessible_get_parent (AtspiAccessible *obj, GError **error)
     dbus_message_iter_init (reply, &iter);
     dbus_message_iter_recurse (&iter, &iter_variant);
     g_clear_object (&obj->accessible_parent);
-    obj->accessible_parent = _atspi_dbus_return_accessible_from_iter (&iter_variant);
+    obj->accessible_parent = _atspi_dbus_consume_accessible (&iter_variant);
     dbus_message_unref (reply);
     _atspi_accessible_add_cache (obj, ATSPI_CACHE_PARENT);
   }
@@ -968,7 +968,6 @@ _atspi_accessible_is_a (AtspiAccessible *accessible,
     dbus_message_iter_init (reply, &iter);
     _atspi_dbus_set_interfaces (accessible, &iter);
     dbus_message_unref (reply);
-    _atspi_accessible_add_cache (accessible, ATSPI_CACHE_INTERFACES);
   }
 
   n = _atspi_get_iface_num (interface_name);
diff --git a/atspi/atspi-collection.c b/atspi/atspi-collection.c
index d4d15372..34fbbabe 100644
--- a/atspi/atspi-collection.c
+++ b/atspi/atspi-collection.c
@@ -91,7 +91,7 @@ return_accessibles (DBusMessage *message)
   while (dbus_message_iter_get_arg_type (&iter_array) != DBUS_TYPE_INVALID)
   {
     AtspiAccessible *accessible;
-    accessible = _atspi_dbus_return_accessible_from_iter (&iter_array);
+    accessible = _atspi_dbus_consume_accessible (&iter_array);
     ret = g_array_append_val (ret, accessible);
     /* Iter was moved already, so no need to call dbus_message_iter_next */
   }
diff --git a/atspi/atspi-event-listener.c b/atspi/atspi-event-listener.c
index d591115c..68eb921e 100644
--- a/atspi/atspi-event-listener.c
+++ b/atspi/atspi-event-listener.c
@@ -1139,7 +1139,7 @@ _atspi_dbus_handle_event (DBusConnection *bus, DBusMessage *message)
       else
       {
         AtspiAccessible *accessible;
- 	accessible = _atspi_dbus_return_accessible_from_iter (&iter_variant);
+ 	accessible = _atspi_dbus_consume_accessible (&iter_variant);
         if (!strcmp (category, "ScreenReader"))
         {
           g_object_unref (e.source);
diff --git a/atspi/atspi-misc-private.h b/atspi/atspi-misc-private.h
index e76a1a94..b3040d5d 100644
--- a/atspi/atspi-misc-private.h
+++ b/atspi/atspi-misc-private.h
@@ -81,7 +81,7 @@ AtspiAccessible *
 _atspi_dbus_return_accessible_from_message (DBusMessage *message);
 
 AtspiAccessible *
-_atspi_dbus_return_accessible_from_iter (DBusMessageIter *iter);
+_atspi_dbus_consume_accessible (DBusMessageIter *iter);
 
 AtspiHyperlink *
 _atspi_dbus_return_hyperlink_from_message (DBusMessage *message);
diff --git a/atspi/atspi-misc.c b/atspi/atspi-misc.c
index 1fb39929..18abfceb 100644
--- a/atspi/atspi-misc.c
+++ b/atspi/atspi-misc.c
@@ -410,7 +410,7 @@ add_app_to_desktop (AtspiAccessible *a, const char *bus_name)
   return (obj != NULL);
 }
 
-void
+static void
 get_reference_from_iter (DBusMessageIter *iter, const char **app_name, const char **path)
 {
   DBusMessageIter iter_struct;
@@ -426,8 +426,8 @@ static void
 add_accessible_from_iter (DBusMessageIter *iter)
 {
   DBusMessageIter iter_struct, iter_array;
-  const char *app_name, *path;
   AtspiAccessible *accessible;
+  AtspiAccessible *parent;
   const char *name, *description;
   dbus_uint32_t role;
   gboolean children_cached = FALSE;
@@ -436,8 +436,7 @@ add_accessible_from_iter (DBusMessageIter *iter)
   dbus_message_iter_recurse (iter, &iter_struct);
 
   /* get accessible */
-  get_reference_from_iter (&iter_struct, &app_name, &path);
-  accessible = ref_accessible (app_name, path);
+  accessible = _atspi_dbus_consume_accessible (&iter_struct);
   if (!accessible)
     return;
 
@@ -445,10 +444,10 @@ add_accessible_from_iter (DBusMessageIter *iter)
   dbus_message_iter_next (&iter_struct);
 
   /* get parent */
-  get_reference_from_iter (&iter_struct, &app_name, &path);
+  parent = _atspi_dbus_consume_accessible (&iter_struct);
   if (accessible->accessible_parent)
     g_object_unref (accessible->accessible_parent);
-  accessible->accessible_parent = ref_accessible (app_name, path);
+  accessible->accessible_parent = parent;
 
   if (dbus_message_iter_get_arg_type (&iter_struct) == 'i')
   {
@@ -487,8 +486,7 @@ add_accessible_from_iter (DBusMessageIter *iter)
     while (dbus_message_iter_get_arg_type (&iter_array) != DBUS_TYPE_INVALID)
     {
       AtspiAccessible *child;
-      get_reference_from_iter (&iter_array, &app_name, &path);
-      child = ref_accessible (app_name, path);
+      child = _atspi_dbus_consume_accessible (&iter_array);
       g_ptr_array_remove (accessible->children, child);
       g_ptr_array_add (accessible->children, child);
     }
@@ -661,7 +659,7 @@ _atspi_dbus_return_accessible_from_message (DBusMessage *message)
   if (!strcmp (signature, "(so)"))
   {
     dbus_message_iter_init (message, &iter);
-    retval =  _atspi_dbus_return_accessible_from_iter (&iter);
+    retval =  _atspi_dbus_consume_accessible (&iter);
   }
   else
   {
@@ -671,8 +669,9 @@ _atspi_dbus_return_accessible_from_message (DBusMessage *message)
   return retval;
 }
 
+/* Enters an iter which must be already pointing to a (so) and returns the accessible for it */
 AtspiAccessible *
-_atspi_dbus_return_accessible_from_iter (DBusMessageIter *iter)
+_atspi_dbus_consume_accessible (DBusMessageIter *iter)
 {
   const char *app_name, *path;
 
@@ -1251,7 +1250,7 @@ _atspi_dbus_get_property (gpointer obj, const char *interface, const char *name,
   }
   if (!strcmp (type, "(so)"))
   {
-    *((AtspiAccessible **)data) = _atspi_dbus_return_accessible_from_iter (&iter_variant);
+    *((AtspiAccessible **)data) = _atspi_dbus_consume_accessible (&iter_variant);
   }
   else
   {
@@ -1379,36 +1378,98 @@ _atspi_dbus_attribute_array_from_iter (DBusMessageIter *iter)
   return array;
 }
 
-void
-_atspi_dbus_set_interfaces (AtspiAccessible *accessible, DBusMessageIter *iter)
+typedef enum {
+  DEMARSHAL_STATUS_SUCCESS,
+  DEMARSHAL_STATUS_INVALID_SIGNATURE,
+  DEMARSHAL_STATUS_INVALID_VALUE,
+} DemarshalStatus;
+
+typedef struct {
+  /* array of (char *) */
+  GPtrArray *names;
+} InterfaceNames;
+
+static DemarshalStatus
+interface_names_demarshal (DBusMessageIter *iter, InterfaceNames **out_interfaces)
 {
-  DBusMessageIter iter_array;
-  char *iter_sig = dbus_message_iter_get_signature (iter);
+  char *sig = dbus_message_iter_get_signature (iter);
+  gboolean matches = strcmp (sig, "as") == 0;
+  dbus_free (sig);
 
-  accessible->interfaces = 0;
-  if (strcmp (iter_sig, "as") != 0)
+  *out_interfaces = NULL;
+
+  GPtrArray *names = g_ptr_array_new_with_free_func (g_free);
+
+  if (!matches)
   {
-    g_warning ("_atspi_dbus_set_interfaces: Passed iterator with invalid signature %s", iter_sig);
-    dbus_free (iter_sig);
-    return;
+    return DEMARSHAL_STATUS_INVALID_SIGNATURE;
   }
-  dbus_free (iter_sig);
+
+  DBusMessageIter iter_array;
   dbus_message_iter_recurse (iter, &iter_array);
   while (dbus_message_iter_get_arg_type (&iter_array) != DBUS_TYPE_INVALID)
   {
     const char *iface;
-    gint n;
     dbus_message_iter_get_basic (&iter_array, &iface);
-    if (!strcmp (iface, "org.freedesktop.DBus.Introspectable")) continue;
-    n = _atspi_get_iface_num (iface);
-    if (n == -1)
+    g_ptr_array_add (names, g_strdup (iface));
+    dbus_message_iter_next (&iter_array);
+  }
+
+  InterfaceNames *ifaces = g_new0 (InterfaceNames, 1);
+  ifaces->names = names;
+  *out_interfaces = ifaces;
+  return DEMARSHAL_STATUS_SUCCESS;
+}
+
+/* Converts an array of interface names to a value suitable for AtspiAccessible.interfaces */
+static gint
+interface_names_to_bitmask (const InterfaceNames *ifaces)
+{
+  gint val = 0;
+  guint i;
+
+  g_assert (ifaces->names != NULL);
+
+  for (i = 0; i < ifaces->names->len; i++)
     {
-      g_warning ("AT-SPI: Unknown interface %s", iface);
+      const char *name = g_ptr_array_index (ifaces->names, i);
+      gint iface_num = _atspi_get_iface_num (name);
+      if (iface_num == -1)
+        {
+          g_warning ("AT-SPI: Unknown interface %s", name);
+        }
+      else
+        {
+          val |= (1 << iface_num);
+        }
     }
-    else
-      accessible->interfaces |= (1 << n);
-    dbus_message_iter_next (&iter_array);
+
+  return val;
+}
+
+static void
+interface_names_free (InterfaceNames *ifaces)
+{
+  g_ptr_array_free (ifaces->names, TRUE);
+  g_free (ifaces);
+}
+
+void
+_atspi_dbus_set_interfaces (AtspiAccessible *accessible, DBusMessageIter *iter)
+{
+  InterfaceNames *ifaces;
+
+  accessible->interfaces = 0;
+
+  if (interface_names_demarshal (iter, &ifaces) != DEMARSHAL_STATUS_SUCCESS)
+  {
+    g_warning ("Passed iterator with invalid signature");
+    return;
   }
+
+  accessible->interfaces = interface_names_to_bitmask (ifaces);
+  interface_names_free (ifaces);
+
   _atspi_accessible_add_cache (accessible, ATSPI_CACHE_INTERFACES);
 }
 
diff --git a/atspi/atspi-relation.c b/atspi/atspi-relation.c
index c441f2bb..10063439 100644
--- a/atspi/atspi-relation.c
+++ b/atspi/atspi-relation.c
@@ -99,7 +99,7 @@ _atspi_relation_new_from_iter (DBusMessageIter *iter)
   while (dbus_message_iter_get_arg_type (&iter_array) != DBUS_TYPE_INVALID)
   {
     AtspiAccessible *accessible;
-    accessible = _atspi_dbus_return_accessible_from_iter (&iter_array);
+    accessible = _atspi_dbus_consume_accessible (&iter_array);
     relation->targets = g_array_append_val (relation->targets, accessible);
     /* Iter was moved already, so no need to call dbus_message_iter_next */
   }
diff --git a/atspi/atspi-table-cell.c b/atspi/atspi-table-cell.c
index 83fe534c..a33e0a89 100644
--- a/atspi/atspi-table-cell.c
+++ b/atspi/atspi-table-cell.c
@@ -46,7 +46,7 @@ get_object_array_and_unref (DBusMessage *reply)
   dbus_message_iter_recurse (&iter, &iter_array);
   while (dbus_message_iter_get_arg_type (&iter_array) != DBUS_TYPE_INVALID)
   {
-    AtspiAccessible *accessible = _atspi_dbus_return_accessible_from_iter (&iter_array);
+    AtspiAccessible *accessible = _atspi_dbus_consume_accessible (&iter_array);
     g_ptr_array_add (array, accessible);
   }
   dbus_message_unref (reply);
diff --git a/ci/container_builds.yml b/ci/container_builds.yml
index e9d268a0..40dc6f24 100644
--- a/ci/container_builds.yml
+++ b/ci/container_builds.yml
@@ -13,7 +13,7 @@ include:
 variables:
   # When branching change the suffix to avoid conflicts with images
   # from the main branch
-  BASE_TAG: "2022-07-07.0-main"
+  BASE_TAG: "2022-07-12.0-main"
   RUST_STABLE: "1.58.1"
 
 .container.opensuse@x86_64:
@@ -23,11 +23,34 @@ variables:
     FDO_DISTRIBUTION_VERSION: "tumbleweed"
     FDO_UPSTREAM_REPO: "gnome/at-spi2-core"
     FDO_DISTRIBUTION_PACKAGES: >-
-      bzip2 clang clang-tools findutils gcc dbus-1 dbus-1-devel gettext git
-      glib2-devel gobject-introspection-devel
-      gsettings-desktop-schemas gtk-doc itstool libasan6 libxml2-devel
-      libxkbcommon-devel libXi-devel libXtst-devel lcov llvm meson ninja
-      python310 python310-python-dbusmock python310-gobject tar wget
+      bzip2
+      clang
+      clang-tools
+      dbus-1
+      dbus-1-devel
+      findutils
+      gcc
+      gettext
+      git
+      glib2-devel
+      gobject-introspection-devel
+      gsettings-desktop-schemas
+      gtk-doc
+      itstool
+      libXi-devel
+      libXtst-devel
+      libasan6
+      libxkbcommon-devel
+      libxml2-devel
+      llvm
+      meson
+      ninja
+      python310
+      python310-gobject
+      python310-pytest
+      python310-python-dbusmock
+      tar
+      wget
     FDO_DISTRIBUTION_EXEC: >-
       bash ci/install-rust.sh ${RUST_STABLE} x86_64-unknown-linux-gnu
 
@@ -44,10 +67,30 @@ opensuse-container@x86_64:
     FDO_DISTRIBUTION_VERSION: "35"
     FDO_UPSTREAM_REPO: "gnome/at-spi2-core"
     FDO_DISTRIBUTION_PACKAGES: >-
-      clang clang-tools-extra findutils gcc dbus-daemon dbus-devel dbus-tools systemd-devel
-      gettext git glib2-devel gobject-introspection-devel
-      gsettings-desktop-schemas gtk-doc itstool libasan libxml2-devel
-      libxkbcommon-devel libXi-devel libXtst-devel lcov meson procps python38
+      clang
+      clang-tools-extra
+      dbus-daemon
+      dbus-devel
+      dbus-tools
+      findutils
+      gcc
+      gettext
+      git
+      glib2-devel
+      gobject-introspection-devel
+      gsettings-desktop-schemas
+      gtk-doc
+      itstool
+      lcov
+      libXi-devel
+      libXtst-devel
+      libasan
+      libxkbcommon-devel
+      libxml2-devel
+      meson
+      procps
+      python38
+      systemd-devel
 
 fedora-container@x86_64:
   extends:
diff --git a/ci/run-registryd-tests.sh b/ci/run-registryd-tests.sh
new file mode 100755
index 00000000..62eb1118
--- /dev/null
+++ b/ci/run-registryd-tests.sh
@@ -0,0 +1,24 @@
+#!/bin/sh
+
+set -eu
+
+echo "About to run the tests.  First we'll launch a gnome-session DBus mock."
+
+python3 -m dbusmock --session org.gnome.SessionManager /org/gnome/SessionManager org.gnome.SessionManager &
+sleep 1
+
+gdbus call --session \
+      --dest org.gnome.SessionManager \
+      --object-path /org/gnome/SessionManager \
+      --method org.freedesktop.DBus.Mock.AddTemplate 'tests/dbusmock/mock-gnome-session.py' '{}'
+
+gdbus call --session \
+      --dest org.gnome.SessionManager \
+      --object-path /org/gnome/SessionManager \
+      --method org.freedesktop.DBus.Mock.SetSessionRunning true
+
+mkdir -p _build/tests/registryd
+
+cd tests/registryd
+
+pytest -v --junit-xml=../../_build/tests/registryd/registryd-pytest.junit.xml
diff --git a/dbind/dbtest.c b/dbind/dbtest.c
index d4f56906..22ea2165 100644
--- a/dbind/dbtest.c
+++ b/dbind/dbtest.c
@@ -367,9 +367,8 @@ void test_helpers ()
 
 int main (int argc, char **argv)
 {
-    DBusConnection *bus;
-
-    bus = dbus_bus_get (DBUS_BUS_SESSION, NULL);
+    DBusConnection *bus = dbus_bus_get (DBUS_BUS_SESSION, NULL);
+    g_assert (bus != NULL);
 
     test_helpers ();
     test_marshalling ();
diff --git a/registryd/de-types.h b/registryd/de-types.h
index ea05dda7..d26cc90f 100644
--- a/registryd/de-types.h
+++ b/registryd/de-types.h
@@ -51,9 +51,7 @@ typedef enum {
     Accessibility_KEY_UNLOCKMODIFIERS,
 } Accessibility_KeySynthType;
 
-typedef struct _Accessibility_DeviceEvent Accessibility_DeviceEvent;
-struct _Accessibility_DeviceEvent
-{
+typedef struct {
   Accessibility_EventType type;
   dbus_uint32_t id;
   dbus_uint32_t hw_code;
@@ -61,23 +59,19 @@ struct _Accessibility_DeviceEvent
   dbus_uint32_t timestamp;
   char * event_string;
   dbus_bool_t is_text;
-};
+} Accessibility_DeviceEvent;
 
-typedef struct _Accessibility_EventListenerMode Accessibility_EventListenerMode;
-struct _Accessibility_EventListenerMode
-{
+typedef struct {
   dbus_bool_t synchronous;
   dbus_bool_t preemptive;
   dbus_bool_t global;
-};
+} Accessibility_EventListenerMode;
 
-typedef struct _Accessibility_KeyDefinition Accessibility_KeyDefinition;
-struct _Accessibility_KeyDefinition
-{
+typedef struct {
   dbus_int32_t keycode;
   dbus_int32_t keysym;
   char *keystring;
   dbus_int32_t unused;
-};
+} Accessibility_KeyDefinition;
 
 #endif /* SPI_DE_TYPES_H_ */
diff --git a/registryd/deviceeventcontroller-x11.c b/registryd/deviceeventcontroller-x11.c
index 40973fa2..010fdf0a 100644
--- a/registryd/deviceeventcontroller-x11.c
+++ b/registryd/deviceeventcontroller-x11.c
@@ -64,11 +64,10 @@ static Accessibility_DeviceEvent pressed_event;
 static void wait_for_release_event (XEvent *event, SpiDEController *controller);
 
 static int spi_error_code = 0;
-struct _SpiPoint {
+typedef struct {
     gint x;
     gint y;
-};
-typedef struct _SpiPoint SpiPoint;
+} SpiPoint;
 static SpiPoint last_mouse_pos_static = {0, 0}; 
 static SpiPoint *last_mouse_pos = &last_mouse_pos_static;
 static unsigned int mouse_mask_state = 0;
diff --git a/registryd/deviceeventcontroller.c b/registryd/deviceeventcontroller.c
index 0fe65556..740995f4 100644
--- a/registryd/deviceeventcontroller.c
+++ b/registryd/deviceeventcontroller.c
@@ -72,11 +72,11 @@ typedef struct {
 
 /* A pointer to our parent object class */
 static int spi_error_code = 0;
-struct _SpiPoint {
+
+typedef struct {
     gint x;
     gint y;
-};
-typedef struct _SpiPoint SpiPoint;
+} SpiPoint;
 
 static unsigned int mouse_mask_state = 0;
 static unsigned int key_modifier_mask =
diff --git a/registryd/event-source.c b/registryd/event-source.c
index e82908ae..ca4340c5 100644
--- a/registryd/event-source.c
+++ b/registryd/event-source.c
@@ -24,8 +24,7 @@
 
 #include "event-source.h"
 
-typedef struct _DisplaySource
-{
+typedef struct {
   GSource source;
   
   Display *display;
diff --git a/registryd/registry.c b/registryd/registry.c
index b09c0e31..5e08f6e4 100644
--- a/registryd/registry.c
+++ b/registryd/registry.c
@@ -30,30 +30,17 @@
 #include "registry.h"
 #include "introspection.h"
 
-typedef struct event_data event_data;
-struct event_data
+typedef struct
 {
   gchar *listener_bus_name;
   gchar *app_bus_name;
   gchar **data;
   GSList *properties;
-};
-
-static void
-children_added_listener (DBusConnection * bus,
-                         gint             index,
-                         const gchar    * name,
-                         const gchar    * path);
-
-static void
-children_removed_listener (DBusConnection * bus,
-                           gint             index,
-                           const gchar    * name,
-                           const gchar    * path);
+} EventData;
 
 /*---------------------------------------------------------------------------*/
 
-typedef struct _SpiReference
+typedef struct
 {
   gchar *name;
   gchar *path;
@@ -84,9 +71,24 @@ spi_reference_free (SpiReference *ref)
 G_DEFINE_TYPE(SpiRegistry, spi_registry, G_TYPE_OBJECT)
 
 static void
+spi_registry_finalize (GObject *object)
+{
+  SpiRegistry *registry = SPI_REGISTRY (object);
+
+  g_clear_pointer (&registry->bus_unique_name, g_free);
+
+  G_OBJECT_CLASS (spi_registry_parent_class)->finalize (object);
+}
+
+static void
 spi_registry_class_init (SpiRegistryClass *klass)
 {
+  GObjectClass *gobject_class;
+
   spi_registry_parent_class = g_type_class_ref (G_TYPE_OBJECT);
+
+  gobject_class = G_OBJECT_CLASS (klass);
+  gobject_class->finalize = spi_registry_finalize;
 }
 
 static void
@@ -162,21 +164,58 @@ find_index_of_reference (GPtrArray *arr, const gchar *name, const gchar * path,
 }
 
 static void
-add_application (SpiRegistry *reg, DBusConnection *bus, const gchar *name, const gchar *path)
+emit_event (DBusConnection *bus,
+            const char *iface_name,
+            const char *signal_name,
+            const char *detail_str,
+            dbus_int32_t detail1,
+            dbus_int32_t detail2,
+            SpiReference *app)
+{
+  DBusMessage *sig;
+  DBusMessageIter iter, iter_variant, iter_array;
+
+  sig = dbus_message_new_signal(SPI_DBUS_PATH_ROOT, iface_name, signal_name);
+
+  dbus_message_iter_init_append(sig, &iter);
+
+  dbus_message_iter_append_basic(&iter, DBUS_TYPE_STRING, &detail_str);
+  dbus_message_iter_append_basic(&iter, DBUS_TYPE_INT32, &detail1);
+  dbus_message_iter_append_basic(&iter, DBUS_TYPE_INT32, &detail2);
+
+  dbus_message_iter_open_container (&iter, DBUS_TYPE_VARIANT, "(so)",
+                                    &iter_variant);
+    append_reference (&iter_variant, app->name, app->path);
+  dbus_message_iter_close_container (&iter, &iter_variant);
+
+  dbus_message_iter_open_container (&iter, DBUS_TYPE_ARRAY, "{sv}",
+                                    &iter_array);
+  dbus_message_iter_close_container (&iter, &iter_array);
+
+  dbus_connection_send(bus, sig, NULL);
+  dbus_message_unref(sig);
+}
+
+static void
+add_application (SpiRegistry *registry, SpiReference *app_root)
 {
-  g_ptr_array_add (reg->apps, spi_reference_new (name, path));
-  children_added_listener (bus, reg->apps->len - 1, name, path);
+  gint index;
+
+  g_ptr_array_add (registry->apps, app_root);
+  index = registry->apps->len - 1;
+
+  emit_event (registry->bus, SPI_DBUS_INTERFACE_EVENT_OBJECT, "ChildrenChanged", "add", index, 0, app_root);
 }
 
 static void
-set_id (SpiRegistry *reg, DBusConnection *bus, const gchar *name, const gchar *path)
+set_id (SpiRegistry *registry, SpiReference *app)
 {
   DBusMessage *message;
   DBusMessageIter iter, iter_variant;
   const char *iface_application = "org.a11y.atspi.Application";
   const char *id = "Id";
 
-  message = dbus_message_new_method_call (name, path,
+  message = dbus_message_new_method_call (app->name, app->path,
                                           DBUS_INTERFACE_PROPERTIES, "Set");
   if (!message)
     return;
@@ -184,22 +223,22 @@ set_id (SpiRegistry *reg, DBusConnection *bus, const gchar *name, const gchar *p
   dbus_message_iter_append_basic (&iter, DBUS_TYPE_STRING, &iface_application);
   dbus_message_iter_append_basic (&iter, DBUS_TYPE_STRING, &id);
   dbus_message_iter_open_container (&iter, DBUS_TYPE_VARIANT, "i", &iter_variant);
-  dbus_message_iter_append_basic (&iter_variant, DBUS_TYPE_INT32, &reg->id);
+  dbus_message_iter_append_basic (&iter_variant, DBUS_TYPE_INT32, &registry->id);
   /* TODO: This will cause problems if we cycle through 2^31 ids */
-  reg->id++;
+  registry->id++;
   dbus_message_iter_close_container (&iter, &iter_variant);
-  dbus_connection_send (bus, message, NULL);
+  dbus_connection_send (registry->bus, message, NULL);
   dbus_message_unref (message);
 }
 
 static void
-remove_application (SpiRegistry *reg, DBusConnection *bus, guint index)
+remove_application (SpiRegistry *registry, guint index)
 {
-  SpiReference *ref = g_ptr_array_index (reg->apps, index);
+  SpiReference *ref = g_ptr_array_index (registry->apps, index);
 
-  spi_remove_device_listeners (reg->dec, ref->name);
-  children_removed_listener (bus, index, ref->name, ref->path);
-  g_ptr_array_remove_index (reg->apps, index);
+  spi_remove_device_listeners (registry->dec, ref->name);
+  emit_event (registry->bus, SPI_DBUS_INTERFACE_EVENT_OBJECT, "ChildrenChanged", "remove", index, 0, ref);
+  g_ptr_array_remove_index (registry->apps, index);
 }
 
 static gboolean
@@ -241,7 +280,7 @@ remove_events (SpiRegistry *registry, const char *bus_name, const char *event)
 
   for (list = registry->events; list;)
     {
-      event_data *evdata = list->data;
+      EventData *evdata = list->data;
       list = list->next;
       if (!g_strcmp0 (evdata->listener_bus_name, bus_name) &&
           event_is_subtype (evdata->data, remove_data))
@@ -275,10 +314,9 @@ remove_events (SpiRegistry *registry, const char *bus_name, const char *event)
 }
 
 static void
-handle_disconnection (DBusConnection *bus, DBusMessage *message, void *user_data)
+handle_disconnection (SpiRegistry *registry, DBusMessage *message)
 {
   char *name, *old, *new;
-  SpiRegistry *reg = SPI_REGISTRY (user_data);
 
   if (dbus_message_get_args (message, NULL,
                              DBUS_TYPE_STRING, &name,
@@ -290,17 +328,17 @@ handle_disconnection (DBusConnection *bus, DBusMessage *message, void *user_data
         {
           /* Remove all children with the application name the same as the disconnected application. */
           guint i;
-          for (i = 0; i < reg->apps->len; i++)
+          for (i = 0; i < registry->apps->len; i++)
             {
-              SpiReference *ref  = g_ptr_array_index (reg->apps, i);
+              SpiReference *ref = g_ptr_array_index (registry->apps, i);
               if (!g_strcmp0 (old, ref->name))
                 {
-                  remove_application (reg, bus, i);
+                  remove_application (registry, i);
                   i--;
                 }
-            } 
+            }
 
-          remove_events (reg, old, "");
+          remove_events (registry, old, "");
         }
     }
 }
@@ -343,7 +381,9 @@ ensure_proper_format (const char *name)
 static DBusHandlerResult
 signal_filter (DBusConnection *bus, DBusMessage *message, void *user_data)
 {
+  SpiRegistry *reg = SPI_REGISTRY (user_data);
   guint res = DBUS_HANDLER_RESULT_HANDLED;
+
   const gint   type    = dbus_message_get_type (message);
   const char *iface = dbus_message_get_interface (message);
   const char *member = dbus_message_get_member (message);
@@ -353,58 +393,83 @@ signal_filter (DBusConnection *bus, DBusMessage *message, void *user_data)
 
   if (!g_strcmp0(iface, DBUS_INTERFACE_DBUS) &&
       !g_strcmp0(member, "NameOwnerChanged"))
-      handle_disconnection (bus, message, user_data);
+      handle_disconnection (reg, message);
   else
       res = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 
   return res;
 }
 
+typedef enum {
+  DEMARSHAL_STATUS_SUCCESS,
+  DEMARSHAL_STATUS_INVALID_SIGNATURE,
+  DEMARSHAL_STATUS_INVALID_VALUE,
+} DemarshalStatus;
+
 /* org.at_spi.Socket interface */
 /*---------------------------------------------------------------------------*/
 
-static DBusMessage*
-impl_Embed (DBusConnection *bus, DBusMessage *message, void *user_data)
+static DemarshalStatus
+socket_embed_demarshal (DBusMessage *message, SpiReference **out_app_root)
 {
-  SpiRegistry *reg = SPI_REGISTRY (user_data);
   DBusMessageIter iter, iter_struct;
   const gchar *app_name, *obj_path;
-
-  DBusMessage *reply = NULL;
-  DBusMessageIter reply_iter;
+  SpiReference *app_root;
 
   dbus_message_iter_init (message, &iter);
   dbus_message_iter_recurse (&iter, &iter_struct);
   if (!(dbus_message_iter_get_arg_type (&iter_struct) == DBUS_TYPE_STRING))
-	goto error;
+    return DEMARSHAL_STATUS_INVALID_SIGNATURE;
   dbus_message_iter_get_basic (&iter_struct, &app_name);
   if (!app_name)
     app_name = dbus_message_get_sender (message);
   if (!dbus_message_iter_next (&iter_struct))
-        goto error;
+    return DEMARSHAL_STATUS_INVALID_SIGNATURE;
   if (!(dbus_message_iter_get_arg_type (&iter_struct) == DBUS_TYPE_OBJECT_PATH))
-	goto error;
+    return DEMARSHAL_STATUS_INVALID_SIGNATURE;
   dbus_message_iter_get_basic (&iter_struct, &obj_path);
 
-  add_application(reg, bus, app_name, obj_path);
+  app_root = spi_reference_new (app_name, obj_path);
+  *out_app_root = app_root;
+
+  return DEMARSHAL_STATUS_SUCCESS;
+}
+
+static SpiReference *
+socket_embed (SpiRegistry *registry, SpiReference *app_root)
+{
+  add_application (registry, app_root);
+  set_id (registry, app_root);
+  return spi_reference_new (registry->bus_unique_name, SPI_DBUS_PATH_ROOT);
+}
+
+static DBusMessage*
+impl_Embed (DBusMessage *message, SpiRegistry *registry)
+{
+  SpiReference *app_root = NULL;
+  SpiReference *result;
+
+  if (socket_embed_demarshal (message, &app_root) != DEMARSHAL_STATUS_SUCCESS)
+    {
+      return dbus_message_new_error (message, DBUS_ERROR_FAILED, "Invalid arguments");
+    }
+
+  DBusMessage *reply = NULL;
+  DBusMessageIter reply_iter;
 
-  set_id (reg, bus, app_name, obj_path);
+  result = socket_embed (registry, app_root); /* takes ownership of the app_root */
 
   reply = dbus_message_new_method_return (message);
   dbus_message_iter_init_append (reply, &reply_iter);
-  append_reference (&reply_iter, 
-                    dbus_bus_get_unique_name (bus),
-                    SPI_DBUS_PATH_ROOT);
+  append_reference (&reply_iter, result->name, result->path);
+  spi_reference_free (result);
 
   return reply;
-error:
-  return dbus_message_new_error (message, DBUS_ERROR_FAILED, "Invalid arguments");
 }
 
 static DBusMessage*
-impl_Unembed (DBusConnection *bus, DBusMessage *message, void *user_data)
+impl_Unembed (DBusMessage *message, SpiRegistry *registry)
 {
-  SpiRegistry *reg = SPI_REGISTRY (user_data);
   DBusMessageIter iter, iter_struct;
   gchar *app_name, *obj_path;
   guint index;
@@ -420,8 +485,8 @@ impl_Unembed (DBusConnection *bus, DBusMessage *message, void *user_data)
 	goto error;
   dbus_message_iter_get_basic (&iter_struct, &obj_path);
 
-  if (find_index_of_reference (reg->apps, app_name, obj_path, &index))
-      remove_application(reg, bus, index);
+  if (find_index_of_reference (registry->apps, app_name, obj_path, &index))
+    remove_application (registry, index);
 
   return NULL;
 error:
@@ -432,7 +497,7 @@ error:
 /*---------------------------------------------------------------------------*/
 
 static DBusMessage *
-impl_Contains (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_Contains (DBusMessage * message, SpiRegistry *registry)
 {
   dbus_bool_t retval = FALSE;
   DBusMessage *reply;
@@ -444,8 +509,7 @@ impl_Contains (DBusConnection * bus, DBusMessage * message, void *user_data)
 }
 
 static DBusMessage *
-impl_GetAccessibleAtPoint (DBusConnection * bus, DBusMessage * message,
-                           void *user_data)
+impl_GetAccessibleAtPoint (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply = NULL;
   DBusMessageIter iter;
@@ -453,14 +517,14 @@ impl_GetAccessibleAtPoint (DBusConnection * bus, DBusMessage * message,
   reply = dbus_message_new_method_return (message);
   dbus_message_iter_init_append (reply, &iter);
   append_reference (&iter, 
-                    dbus_bus_get_unique_name (bus),
+                    registry->bus_unique_name,
                     SPI_DBUS_PATH_NULL);
 
   return reply;
 }
 
 static DBusMessage *
-impl_GetExtents (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GetExtents (DBusMessage * message, SpiRegistry *registry)
 {
   dbus_int32_t x = 0, y = 0, width = 1024, height = 768;
   DBusMessage *reply;
@@ -479,8 +543,7 @@ impl_GetExtents (DBusConnection * bus, DBusMessage * message, void *user_data)
 }
 
 static DBusMessage *
-impl_GetPosition (DBusConnection * bus, DBusMessage * message,
-                  void *user_data)
+impl_GetPosition (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   dbus_int32_t x = 0, y = 0;
@@ -492,7 +555,7 @@ impl_GetPosition (DBusConnection * bus, DBusMessage * message,
 }
 
 static DBusMessage *
-impl_GetSize (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GetSize (DBusMessage * message, SpiRegistry *registry)
 {
   /* TODO - Get the screen size */
   DBusMessage *reply;
@@ -507,7 +570,7 @@ impl_GetSize (DBusConnection * bus, DBusMessage * message, void *user_data)
 #define LAYER_WIDGET 3;
 
 static DBusMessage *
-impl_GetLayer (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GetLayer (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   dbus_uint32_t rv = LAYER_WIDGET;
@@ -519,8 +582,7 @@ impl_GetLayer (DBusConnection * bus, DBusMessage * message, void *user_data)
 }
 
 static DBusMessage *
-impl_GetMDIZOrder (DBusConnection * bus, DBusMessage * message,
-                   void *user_data)
+impl_GetMDIZOrder (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   dbus_int16_t rv = 0;
@@ -532,7 +594,7 @@ impl_GetMDIZOrder (DBusConnection * bus, DBusMessage * message,
 }
 
 static DBusMessage *
-impl_GrabFocus (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GrabFocus (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   dbus_bool_t retval = FALSE;
@@ -544,7 +606,7 @@ impl_GrabFocus (DBusConnection * bus, DBusMessage * message, void *user_data)
 }
 
 static DBusMessage *
-impl_GetAlpha (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GetAlpha (DBusMessage * message, SpiRegistry *registry)
 {
   double rv = 1.0;
   DBusMessage *reply;
@@ -559,21 +621,21 @@ impl_GetAlpha (DBusConnection * bus, DBusMessage * message, void *user_data)
 /*---------------------------------------------------------------------------*/
 
 static dbus_bool_t
-impl_get_Name (DBusMessageIter * iter, void *user_data)
+impl_get_Name (DBusMessageIter * iter, SpiRegistry *registry)
 {
   const gchar *name = "main";
   return return_v_string (iter, name);
 }
 
 static dbus_bool_t
-impl_get_Description (DBusMessageIter * iter, void *user_data)
+impl_get_Description (DBusMessageIter * iter, SpiRegistry *registry)
 {
   const gchar *description = "";
   return return_v_string (iter, description);
 }
 
 static dbus_bool_t
-impl_get_Parent (DBusMessageIter * iter, void *user_data)
+impl_get_Parent (DBusMessageIter * iter, SpiRegistry *registry)
 {
   const gchar *name = "";
   DBusMessageIter iter_variant;
@@ -588,10 +650,9 @@ impl_get_Parent (DBusMessageIter * iter, void *user_data)
 }
 
 static dbus_bool_t
-impl_get_ChildCount (DBusMessageIter * iter, void *user_data)
+impl_get_ChildCount (DBusMessageIter * iter, SpiRegistry *registry)
 {
-  SpiRegistry *reg = SPI_REGISTRY (user_data);
-  dbus_int32_t rv = reg->apps->len;
+  dbus_int32_t rv = registry->apps->len;
   dbus_bool_t result;
   DBusMessageIter iter_variant;
 
@@ -604,22 +665,20 @@ impl_get_ChildCount (DBusMessageIter * iter, void *user_data)
 }
 
 static dbus_bool_t
-impl_get_ToolkitName (DBusMessageIter * iter, void *user_data)
+impl_get_ToolkitName (DBusMessageIter * iter, SpiRegistry *registry)
 {
   return return_v_string (iter, "at-spi-registry");
 }
 
 static dbus_bool_t
-impl_get_ToolkitVersion (DBusMessageIter * iter, void *user_data)
+impl_get_ToolkitVersion (DBusMessageIter * iter, SpiRegistry *registry)
 {
   return return_v_string (iter, "2.0");
 }
 
 static DBusMessage *
-impl_GetChildAtIndex (DBusConnection * bus,
-                      DBusMessage * message, void *user_data)
+impl_GetChildAtIndex (DBusMessage * message, SpiRegistry *registry)
 {
-  SpiRegistry *reg = SPI_REGISTRY (user_data);
   DBusMessage *reply;
   DBusMessageIter iter;
   DBusError error;
@@ -636,11 +695,11 @@ impl_GetChildAtIndex (DBusConnection * bus,
   reply = dbus_message_new_method_return (message);
   dbus_message_iter_init_append (reply, &iter);
 
-  if (i < 0 || i >= reg->apps->len)
+  if (i < 0 || i >= registry->apps->len)
     append_reference (&iter, SPI_DBUS_NAME_REGISTRY, SPI_DBUS_PATH_NULL);
   else
     {
-      ref = g_ptr_array_index (reg->apps, i);
+      ref = g_ptr_array_index (registry->apps, i);
       append_reference (&iter, ref->name, ref->path);
     }
 
@@ -648,21 +707,19 @@ impl_GetChildAtIndex (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetChildren (DBusConnection * bus,
-                  DBusMessage * message, void *user_data)
+impl_GetChildren (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply = NULL;
   DBusMessageIter iter, iter_array;
-  SpiRegistry *reg = SPI_REGISTRY (user_data);
   int i;
 
   reply = dbus_message_new_method_return (message);
 
   dbus_message_iter_init_append (reply, &iter);
   dbus_message_iter_open_container(&iter, DBUS_TYPE_ARRAY, "(so)", &iter_array);
-  for (i=0; i < reg->apps->len; i++)
+  for (i=0; i < registry->apps->len; i++)
     {
-      SpiReference *current = g_ptr_array_index (reg->apps, i);
+      SpiReference *current = g_ptr_array_index (registry->apps, i);
       append_reference (&iter_array, current->name, current->path);
     }
   dbus_message_iter_close_container(&iter, &iter_array);
@@ -670,8 +727,7 @@ impl_GetChildren (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetIndexInParent (DBusConnection * bus,
-                       DBusMessage * message, void *user_data)
+impl_GetIndexInParent (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   dbus_uint32_t rv = 0;
@@ -682,8 +738,7 @@ impl_GetIndexInParent (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetRelationSet (DBusConnection * bus,
-                     DBusMessage * message, void *user_data)
+impl_GetRelationSet (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   DBusMessageIter iter, iter_array;
@@ -697,7 +752,7 @@ impl_GetRelationSet (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetRole (DBusConnection * bus, DBusMessage * message, void * user_data)
+impl_GetRole (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   dbus_uint32_t rv = 14;	/* TODO: Get DESKTOP_FRAME from somewhere */
@@ -708,8 +763,7 @@ impl_GetRole (DBusConnection * bus, DBusMessage * message, void * user_data)
 }
 
 static DBusMessage *
-impl_GetRoleName (DBusConnection * bus,
-                  DBusMessage * message, void *user_data)
+impl_GetRoleName (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   const char *role_name = "desktop frame";
@@ -721,8 +775,7 @@ impl_GetRoleName (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetLocalizedRoleName (DBusConnection * bus,
-                           DBusMessage * message, void *user_data)
+impl_GetLocalizedRoleName (DBusMessage * message, SpiRegistry *registry)
 {
   /* TODO - Localize this */
   DBusMessage *reply;
@@ -735,7 +788,7 @@ impl_GetLocalizedRoleName (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetState (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GetState (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply = NULL;
   DBusMessageIter iter, iter_array;
@@ -757,8 +810,7 @@ impl_GetState (DBusConnection * bus, DBusMessage * message, void *user_data)
 }
 
 static DBusMessage *
-impl_GetAttributes (DBusConnection * bus,
-                    DBusMessage * message, void *user_data)
+impl_GetAttributes (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply = NULL;
   DBusMessageIter iter, array;
@@ -772,8 +824,7 @@ impl_GetAttributes (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetApplication (DBusConnection * bus,
-                     DBusMessage * message, void *user_data)
+impl_GetApplication (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply = NULL;
   DBusMessageIter iter;
@@ -781,15 +832,14 @@ impl_GetApplication (DBusConnection * bus,
   reply = dbus_message_new_method_return (message);
   dbus_message_iter_init_append (reply, &iter);
   append_reference (&iter,
-                    dbus_bus_get_unique_name (bus),
+                    registry->bus_unique_name,
                     SPI_DBUS_PATH_NULL);
 
   return reply;
 }
 
 static DBusMessage *
-impl_GetInterfaces (DBusConnection * bus,
-                    DBusMessage * message, void *user_data)
+impl_GetInterfaces (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   DBusMessageIter iter, iter_array;
@@ -810,7 +860,7 @@ impl_GetInterfaces (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_GetItems (DBusConnection * bus, DBusMessage * message, void *user_data)
+impl_GetItems (DBusMessage * message, SpiRegistry *registry)
 {
   DBusMessage *reply;
   DBusMessageIter iter, iter_array;
@@ -829,12 +879,11 @@ impl_GetItems (DBusConnection * bus, DBusMessage * message, void *user_data)
  * a method call and signal for now.
  */
 static DBusMessage *
-impl_register_event (DBusConnection *bus, DBusMessage *message, void *user_data)
+impl_RegisterEvent (DBusMessage *message, SpiRegistry *registry)
 {
-  SpiRegistry *registry = SPI_REGISTRY (user_data);
   const char *orig_name;
   gchar *name;
-  event_data *evdata;
+  EventData *evdata;
   gchar **data;
   DBusMessage *signal;
   const char *sender = dbus_message_get_sender (message);
@@ -854,7 +903,7 @@ impl_register_event (DBusConnection *bus, DBusMessage *message, void *user_data)
   dbus_message_iter_next (&iter);
   name = ensure_proper_format (orig_name);
 
-  evdata = g_new0 (event_data, 1);
+  evdata = g_new0 (EventData, 1);
   data = g_strsplit (name, ":", 3);
   evdata->listener_bus_name = g_strdup (sender);
   evdata->data = data;
@@ -907,7 +956,7 @@ impl_register_event (DBusConnection *bus, DBusMessage *message, void *user_data)
       ls = g_slist_next (ls);
     }
     dbus_message_iter_close_container (&iter, &iter_array);
-    dbus_connection_send (bus, signal, NULL);
+    dbus_connection_send (registry->bus, signal, NULL);
     dbus_message_unref (signal);
   }
 
@@ -916,9 +965,8 @@ impl_register_event (DBusConnection *bus, DBusMessage *message, void *user_data)
 }
 
 static DBusMessage *
-impl_deregister_event (DBusConnection *bus, DBusMessage *message, void *user_data)
+impl_DeregisterEvent (DBusMessage *message, SpiRegistry *registry)
 {
-  SpiRegistry *registry = SPI_REGISTRY (user_data);
   const char *orig_name;
   gchar *name;
   const char *sender = dbus_message_get_sender (message);
@@ -935,10 +983,9 @@ impl_deregister_event (DBusConnection *bus, DBusMessage *message, void *user_dat
 }
 
 static DBusMessage *
-impl_get_registered_events (DBusConnection *bus, DBusMessage *message, void *user_data)
+impl_GetRegisteredEvents (DBusMessage *message, SpiRegistry *registry)
 {
-  SpiRegistry *registry = SPI_REGISTRY (user_data);
-  event_data *evdata;
+  EventData *evdata;
   DBusMessage *reply;
   DBusMessageIter iter, iter_struct, iter_array;
   GList *list;
@@ -999,8 +1046,7 @@ static const char *introspection_footer =
 "</node>";
 
 static DBusMessage *
-impl_Introspect_root (DBusConnection * bus,
-                 DBusMessage * message, void *user_data)
+impl_Introspect_root (DBusMessage * message, SpiRegistry *registry)
 {
   GString *output;
   gchar *final;
@@ -1027,8 +1073,7 @@ impl_Introspect_root (DBusConnection * bus,
 }
 
 static DBusMessage *
-impl_Introspect_registry (DBusConnection * bus,
-                 DBusMessage * message, void *user_data)
+impl_Introspect_registry (DBusMessage * message, SpiRegistry *registry)
 {
   GString *output;
   gchar *final;
@@ -1055,88 +1100,10 @@ impl_Introspect_registry (DBusConnection * bus,
 
 /*---------------------------------------------------------------------------*/
 
-/*
- * Emits an AT-SPI event.
- * AT-SPI events names are split into three parts:
- * class:major:minor
- * This is mapped onto D-Bus events as:
- * D-Bus Interface:Signal Name:Detail argument
- *
- * Marshals a basic type into the 'any_data' attribute of
- * the AT-SPI event.
- */
-static void 
-emit_event (DBusConnection *bus,
-            const char *klass,
-            const char *major,
-            const char *minor,
-            dbus_int32_t detail1,
-            dbus_int32_t detail2,
-            const char *name,
-            const char *path)
-{
-  DBusMessage *sig;
-  DBusMessageIter iter, iter_variant, iter_array;
-  
-  sig = dbus_message_new_signal(SPI_DBUS_PATH_ROOT, klass, major);
-
-  dbus_message_iter_init_append(sig, &iter);
-
-  dbus_message_iter_append_basic(&iter, DBUS_TYPE_STRING, &minor);
-  dbus_message_iter_append_basic(&iter, DBUS_TYPE_INT32, &detail1);
-  dbus_message_iter_append_basic(&iter, DBUS_TYPE_INT32, &detail2);
-
-  dbus_message_iter_open_container (&iter, DBUS_TYPE_VARIANT, "(so)",
-                                    &iter_variant);
-    append_reference (&iter_variant, name, path);
-  dbus_message_iter_close_container (&iter, &iter_variant);
-
-  dbus_message_iter_open_container (&iter, DBUS_TYPE_ARRAY, "{sv}",
-                                    &iter_array);
-  dbus_message_iter_close_container (&iter, &iter_array);
-
-  dbus_connection_send(bus, sig, NULL);
-  dbus_message_unref(sig);
-}
-
-/*---------------------------------------------------------------------------*/
-
-/*
- * Children changed signal converter and forwarder.
- *
- * Klass (Interface) org.a11y.atspi.Event.Object
- * Major is the signal name.
- * Minor is 'add' or 'remove'
- * detail1 is the index.
- * detail2 is 0.
- * any_data is the child reference.
- */
-
-static void
-children_added_listener (DBusConnection * bus,
-                         gint             index,
-                         const gchar    * name,
-                         const gchar    * path)
-{
-  emit_event (bus, SPI_DBUS_INTERFACE_EVENT_OBJECT, "ChildrenChanged", "add", index, 0,
-              name, path);
-}
-
-static void
-children_removed_listener (DBusConnection * bus,
-                           gint             index,
-                           const gchar    * name,
-                           const gchar    * path)
-{
-  emit_event (bus, SPI_DBUS_INTERFACE_EVENT_OBJECT, "ChildrenChanged", "remove", index, 0,
-              name, path);
-}
-
-/*---------------------------------------------------------------------------*/
-
 static DBusHandlerResult
 handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
 {
+  SpiRegistry *registry = SPI_REGISTRY (user_data);
   DBusHandlerResult result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 
   const gchar *iface   = dbus_message_get_interface (message);
@@ -1177,13 +1144,13 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
               if (!strcmp (prop_iface, SPI_DBUS_INTERFACE_ACCESSIBLE))
                 {
                   if      (!strcmp (prop_member, "Name"))
-                    impl_get_Name (&iter, user_data);
+                    impl_get_Name (&iter, registry);
                   else if (!strcmp (prop_member, "Description"))
-                    impl_get_Description (&iter, user_data);
+                    impl_get_Description (&iter, registry);
                   else if (!strcmp (prop_member, "Parent"))
-                    impl_get_Parent (&iter, user_data);
+                    impl_get_Parent (&iter, registry);
                   else if (!strcmp (prop_member, "ChildCount"))
-                    impl_get_ChildCount (&iter, user_data);
+                    impl_get_ChildCount (&iter, registry);
                   else
                     {
                       dbus_message_unref (reply); 
@@ -1193,9 +1160,9 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
               else if (!strcmp (prop_iface, SPI_DBUS_INTERFACE_APPLICATION))
                 {
                   if (!strcmp (prop_member, "ToolkitName"))
-                    impl_get_ToolkitName (&iter, user_data);
+                    impl_get_ToolkitName (&iter, registry);
                   else if (!strcmp (prop_member, "ToolkitVersion"))
-                    impl_get_ToolkitVersion (&iter, user_data);
+                    impl_get_ToolkitVersion (&iter, registry);
                   else
                     {
                       dbus_message_unref (reply); 
@@ -1224,27 +1191,27 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if      (!strcmp (member, "GetChildAtIndex"))
-          reply = impl_GetChildAtIndex (bus, message, user_data);
+          reply = impl_GetChildAtIndex (message, registry);
       else if (!strcmp (member, "GetChildren"))
-          reply = impl_GetChildren (bus, message, user_data);
+          reply = impl_GetChildren (message, registry);
       else if (!strcmp (member, "GetIndexInParent"))
-          reply = impl_GetIndexInParent (bus, message, user_data);
+          reply = impl_GetIndexInParent (message, registry);
       else if (!strcmp (member, "GetRelationSet"))
-          reply = impl_GetRelationSet (bus, message, user_data);
+          reply = impl_GetRelationSet (message, registry);
       else if (!strcmp (member, "GetRole"))
-          reply = impl_GetRole (bus, message, user_data);
+          reply = impl_GetRole (message, registry);
       else if (!strcmp (member, "GetRoleName"))
-          reply = impl_GetRoleName (bus, message, user_data);
+          reply = impl_GetRoleName (message, registry);
       else if (!strcmp (member, "GetLocalizedRoleName"))
-          reply = impl_GetLocalizedRoleName (bus, message, user_data);
+          reply = impl_GetLocalizedRoleName (message, registry);
       else if (!strcmp (member, "GetState"))
-          reply = impl_GetState (bus, message, user_data);
+          reply = impl_GetState (message, registry);
       else if (!strcmp (member, "GetAttributes"))
-          reply = impl_GetAttributes (bus, message, user_data);
+          reply = impl_GetAttributes (message, registry);
       else if (!strcmp (member, "GetApplication"))
-          reply = impl_GetApplication (bus, message, user_data);
+          reply = impl_GetApplication (message, registry);
       else if (!strcmp (member, "GetInterfaces"))
-          reply = impl_GetInterfaces (bus, message, user_data);
+          reply = impl_GetInterfaces (message, registry);
       else
          result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1253,23 +1220,23 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if      (!strcmp (member, "Contains"))
-          reply = impl_Contains (bus, message, user_data);
+          reply = impl_Contains (message, registry);
       else if (!strcmp (member, "GetAccessibleAtPoint"))
-          reply = impl_GetAccessibleAtPoint (bus, message, user_data);
+          reply = impl_GetAccessibleAtPoint (message, registry);
       else if (!strcmp (member, "GetExtents"))
-          reply = impl_GetExtents (bus, message, user_data);
+          reply = impl_GetExtents (message, registry);
       else if (!strcmp (member, "GetPosition"))
-          reply = impl_GetPosition (bus, message, user_data);
+          reply = impl_GetPosition (message, registry);
       else if (!strcmp (member, "GetSize"))
-          reply = impl_GetSize (bus, message, user_data);
+          reply = impl_GetSize (message, registry);
       else if (!strcmp (member, "GetLayer"))
-          reply = impl_GetLayer (bus, message, user_data);
+          reply = impl_GetLayer (message, registry);
       else if (!strcmp (member, "GetMDIZOrder"))
-          reply = impl_GetMDIZOrder (bus, message, user_data);
+          reply = impl_GetMDIZOrder (message, registry);
       else if (!strcmp (member, "GrabFocus"))
-          reply = impl_GrabFocus (bus, message, user_data);
+          reply = impl_GrabFocus (message, registry);
       else if (!strcmp (member, "GetAlpha"))
-          reply = impl_GetAlpha (bus, message, user_data);
+          reply = impl_GetAlpha (message, registry);
       else
          result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1278,9 +1245,9 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if      (!strcmp (member, "Embed"))
-          reply = impl_Embed (bus, message, user_data);
+          reply = impl_Embed (message, registry);
       else if (!strcmp (member, "Unembed"))
-          reply = impl_Unembed (bus, message, user_data);
+          reply = impl_Unembed (message, registry);
       else
           result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1289,7 +1256,7 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if      (!strcmp (member, "Introspect"))
-          reply = impl_Introspect_root (bus, message, user_data);
+          reply = impl_Introspect_root (message, registry);
       else
           result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1317,6 +1284,7 @@ handle_method_root (DBusConnection *bus, DBusMessage *message, void *user_data)
 static DBusHandlerResult
 handle_method_cache (DBusConnection *bus, DBusMessage *message, void *user_data)
 {
+  SpiRegistry *registry = SPI_REGISTRY (user_data);
   DBusHandlerResult result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 
   const gchar *iface   = dbus_message_get_interface (message);
@@ -1335,7 +1303,7 @@ handle_method_cache (DBusConnection *bus, DBusMessage *message, void *user_data)
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if      (!strcmp (member, "GetItems"))
-          reply = impl_GetItems (bus, message, user_data);
+          reply = impl_GetItems (message, registry);
       else
          result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1356,6 +1324,7 @@ handle_method_cache (DBusConnection *bus, DBusMessage *message, void *user_data)
 static DBusHandlerResult
 handle_method_registry (DBusConnection *bus, DBusMessage *message, void *user_data)
 {
+  SpiRegistry *registry = SPI_REGISTRY (user_data);
   DBusHandlerResult result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 
   const gchar *iface   = dbus_message_get_interface (message);
@@ -1374,11 +1343,11 @@ handle_method_registry (DBusConnection *bus, DBusMessage *message, void *user_da
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if (!strcmp(member, "RegisterEvent"))
-      reply = impl_register_event (bus, message, user_data);
+      reply = impl_RegisterEvent (message, registry);
       else if (!strcmp(member, "DeregisterEvent"))
-        reply = impl_deregister_event (bus, message, user_data);
+        reply = impl_DeregisterEvent (message, registry);
       else if (!strcmp(member, "GetRegisteredEvents"))
-        reply = impl_get_registered_events (bus, message, user_data);
+        reply = impl_GetRegisteredEvents (message, registry);
       else
           result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1387,7 +1356,7 @@ handle_method_registry (DBusConnection *bus, DBusMessage *message, void *user_da
     {
       result = DBUS_HANDLER_RESULT_HANDLED;
       if      (!strcmp (member, "Introspect"))
-          reply = impl_Introspect_registry (bus, message, user_data);
+          reply = impl_Introspect_registry (message, registry);
       else
           result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
     }
@@ -1441,24 +1410,29 @@ static gchar *app_sig_match_name_owner =
 SpiRegistry *
 spi_registry_new (DBusConnection *bus)
 {
-  SpiRegistry *reg = g_object_new (SPI_REGISTRY_TYPE, NULL);
+  SpiRegistry *registry = g_object_new (SPI_REGISTRY_TYPE, NULL);
+  const char *bus_unique_name;
+
+  bus_unique_name = dbus_bus_get_unique_name (bus);
+  g_assert (bus_unique_name != NULL);
 
-  reg->bus = bus;
+  registry->bus = bus;
+  registry->bus_unique_name = g_strdup (bus_unique_name);
 
   dbus_bus_add_match (bus, app_sig_match_name_owner, NULL);
-  dbus_connection_add_filter (bus, signal_filter, reg, NULL);
+  dbus_connection_add_filter (bus, signal_filter, registry, NULL);
 
-  dbus_connection_register_object_path (bus, SPI_DBUS_PATH_ROOT, &root_vtable, reg);
+  dbus_connection_register_object_path (bus, SPI_DBUS_PATH_ROOT, &root_vtable, registry);
 
-  dbus_connection_register_object_path (bus, SPI_DBUS_PATH_CACHE, &cache_vtable, reg);
+  dbus_connection_register_object_path (bus, SPI_DBUS_PATH_CACHE, &cache_vtable, registry);
 
-  dbus_connection_register_object_path (bus, SPI_DBUS_PATH_REGISTRY, &registry_vtable, reg);
+  dbus_connection_register_object_path (bus, SPI_DBUS_PATH_REGISTRY, &registry_vtable, registry);
 
   emit_Available (bus);
 
-  reg->events = NULL;
+  registry->events = NULL;
 
-  return reg;
+  return registry;
 }
 
 /*END------------------------------------------------------------------------*/
diff --git a/registryd/registry.h b/registryd/registry.h
index 19b1a8f0..394a9986 100644
--- a/registryd/registry.h
+++ b/registryd/registry.h
@@ -49,6 +49,7 @@ struct _SpiRegistry {
   dbus_int32_t id;
 
   DBusConnection *bus;
+  char *bus_unique_name;
   GList *events;
 };
 
diff --git a/tests/dbusmock/mock_accessible_app.py b/tests/dbusmock/mock_accessible_app.py
new file mode 100644
index 00000000..11856865
--- /dev/null
+++ b/tests/dbusmock/mock_accessible_app.py
@@ -0,0 +1,75 @@
+import dbus
+import dbus.service
+
+PROPERTIES_IFACE = 'org.freedesktop.DBus.Properties'
+ACCESSIBLE_IFACE = 'org.a11y.atspi.Accessible'
+APPLICATION_IFACE = 'org.a11y.atspi.Application'
+SOCKET_IFACE = 'org.a11y.atspi.Socket'
+
+ROOT_PATH = '/org/a11y/atspi/accessible/root'
+
+def accessible_get_property(prop_name):
+    if prop_name == 'Name':
+        pass # s
+    elif prop_name == 'Description':
+        pass # s
+    elif prop_name == 'Parent':
+        pass # (so)
+    elif prop_name == 'ChildCount':
+        pass # i
+    elif prop_name == 'Locale':
+        pass # s
+    elif prop_name == 'AccessibleId':
+        pass # s
+    else:
+        raise ValueError(f'unknown property name {prop_name}')
+
+def application_get_property(prop_name):
+    return None
+
+@dbus.service.method(PROPERTIES_IFACE, in_signature='ss', out_signature='v')
+def Get(self, iface_name, prop_name):
+    if iface_name == ACCESSIBLE_IFACE:
+        return accessible_get_property(prop_name)
+    elif iface_name == PROPERTY_IFACE:
+        return application_get_property(prop_name)
+
+@dbus.service.method(PROPERTIES_IFACE, in_signature='ssv', out_signature='')
+def Set(self, iface_name, prop_name, value):
+    if iface_name == APPLICATION_IFACE:
+        pass # FIXME
+
+def get_accesssibility_bus_address():
+    bus = dbus.SessionBus()
+    bus_launcher = bus.get_object('org.a11y.Bus', '/org/a11y/bus')
+    return str(bus_launcher.GetAddress(dbus_interface='org.a11y.Bus'))
+
+def get_registry_root(a11y_bus):
+    return a11y_bus.get_object('org.a11y.atspi.Registry', ROOT_PATH)
+
+class MyObject(dbus.service.Object):
+    def __init__(self, a11y_bus, path):
+        dbus.service.Object.__init__(self, a11y_bus, path)
+
+if __name__ == '__main__':
+    from dbus.mainloop.glib import DBusGMainLoop
+    from gi.repository import GLib
+
+    DBusGMainLoop(set_as_default=True)
+    main_loop = GLib.MainLoop()
+
+    a11y_address = get_accesssibility_bus_address()
+    a11y_bus = dbus.bus.BusConnection(a11y_address)
+
+    registry = get_registry_root(a11y_bus)
+    assert registry is not None
+
+    my_unique_name = a11y_bus.get_unique_name()
+    my_root = MyObject(a11y_bus, ROOT_PATH)
+    
+    (registry_bus_name, registry_root_path) = registry.Embed((my_unique_name, my_root), dbus_interface=SOCKET_IFACE)
+
+    print("registry bus name:", registry_bus_name)
+    print("registry_root_path:", registry_root_path)
+
+    # main_loop.run()
diff --git a/tests/registryd/__init__.py b/tests/registryd/__init__.py
new file mode 100644
index 00000000..d18f92c6
--- /dev/null
+++ b/tests/registryd/__init__.py
@@ -0,0 +1 @@
+dummy = "hello"
diff --git a/tests/registryd/conftest.py b/tests/registryd/conftest.py
new file mode 100644
index 00000000..a80af69f
--- /dev/null
+++ b/tests/registryd/conftest.py
@@ -0,0 +1,74 @@
+# This file contains common test fixtures for registryd's tests.
+# Using pytest's terminology for a test's steps:
+#
+# 1. Arrange: create a test fixture; this usually involves a running registry and an accessible app stub.
+#
+# 2. Act: manipulate the app or the registry.
+#
+# 3. Assert: ensure that the thing being manipulated is in the expected state.
+#
+# 4. Cleanup: Terminate the registry and the app.  It is important that the registry exits cleanly,
+#    so it can write out its code coverage information.
+#
+# This module exports the following fixtures:
+#
+# * main_loop - a GLib.MainLoop integrated with the DBusGMainLoop.
+#
+# * session_manager - A mock gnome-session to control the lifetime of daemons.  In
+#   reality, the fixture assumes that there is a gnome-session mock running (see
+#   ci/run-registryd-tests.sh) and just tells that mock to Logout at fixture teardown
+#   time, so that all daemons that monitor the session's lifetime will exit at teardown.
+#
+# * registry - A dbus.proxies.ProxyObject for the registry's root object.  This automatically
+#   depends on a session_manager fixture to control its lifetime.
+
+import pytest
+import dbus
+
+@pytest.fixture
+def main_loop():
+    from dbus.mainloop.glib import DBusGMainLoop
+    from gi.repository import GLib
+
+    DBusGMainLoop(set_as_default=True)
+    loop = GLib.MainLoop()
+    return loop
+
+def get_accesssibility_bus_address():
+    bus = dbus.SessionBus()
+    bus_launcher = bus.get_object('org.a11y.Bus', '/org/a11y/bus')
+    return str(bus_launcher.GetAddress(dbus_interface='org.a11y.Bus'))
+
+def get_registry_root(a11y_bus):
+    return a11y_bus.get_object('org.a11y.atspi.Registry', '/org/a11y/atspi/accessible/root')
+
+@pytest.fixture
+def session_manager():
+    # This assumes that pytest is running in this environment:
+    #
+    # * A session dbus daemon is running
+    #
+    # * There is a gnome-session mock running
+    #
+    # See the ci/run-registryd-tests.sh script to see how that environment is set up.
+
+    import time
+
+    bus = dbus.SessionBus()
+    mock_session = bus.get_object('org.gnome.SessionManager', '/org/gnome/SessionManager')
+
+    # return a dummy object as a fixture
+    yield object()
+
+    # Tell all session clients to terminate
+    mock_session.Logout(0, dbus_interface='org.gnome.SessionManager')
+
+    # Reset mock session back to its starting state
+    mock_session.Reset(dbus_interface='org.freedesktop.DBus.Mock')
+
+@pytest.fixture
+def registry(main_loop, session_manager):
+    a11y_address = get_accesssibility_bus_address()
+    a11y_bus = dbus.bus.BusConnection(a11y_address)
+
+    return get_registry_root(a11y_bus)
diff --git a/tests/registryd/test_registry_startup.py b/tests/registryd/test_registry_startup.py
new file mode 100644
index 00000000..ee00c4b9
--- /dev/null
+++ b/tests/registryd/test_registry_startup.py
@@ -0,0 +1,26 @@
+# Pytest will pick up this module automatically when running just "pytest".
+#
+# Each test_*() function gets passed test fixtures, which are defined
+# in conftest.py.  So, a function "def test_foo(bar)" will get a bar()
+# fixture created for it.
+
+PROPERTIES_IFACE = 'org.freedesktop.DBus.Properties'
+ACCESSIBLE_IFACE = 'org.a11y.atspi.Accessible'
+
+def get_property(proxy, iface_name, prop_name):
+    return proxy.Get(iface_name, prop_name, dbus_interface=PROPERTIES_IFACE)
+
+def test_accessible_iface_properties(registry, session_manager):
+    values = [
+        ('Name',        'main'),
+        ('Description', ''),
+    ]
+
+    for prop_name, expected in values:
+        assert get_property(registry, ACCESSIBLE_IFACE, prop_name) == expected
+
+def test_registry_root_has_null_parent(registry, session_manager):
+    assert get_property(registry, ACCESSIBLE_IFACE, 'Parent') == ('', '/org/a11y/atspi/null')
+
+def test_empty_registry_has_zero_children(registry, session_manager):
+    assert get_property(registry, ACCESSIBLE_IFACE, 'ChildCount') == 0
diff --git a/xml/Socket.xml b/xml/Socket.xml
index ab51850f..a1d19754 100644
--- a/xml/Socket.xml
+++ b/xml/Socket.xml
@@ -1,7 +1,30 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<node>
+<node xmlns:doc="http://www.freedesktop.org/dbus/1.0/doc.dtd">
+  <!--
+      org.a11y.atspi.Socket:
+      @short_description: Interface to register an application on the registry.
+  -->
   <interface name="org.a11y.atspi.Socket">
 
+    <!--
+        Embed:
+        @plug: a string for the unique bus name of the application, and an object path
+        for the application's' root object.
+
+        This is the entry point for an application that wants to register itself against
+        the accessibility registry.  The application's root object, which it passes in
+        @plug, must support the org.a11y.atspi.Application interface.
+
+        When an application calls this method on the registry, the following handshake happens:
+
+        * Application calls this method on the registry to identify itself.
+
+        * The registry sets the "Id" property on the org.a11y.atspi.Application interface on the @plug object.
+
+        * The Embed method returns with the bus name and object path for the registry's root object.
+
+        Returns: the bus name and object path of the registry's root object.
+    -->
     <method name="Embed">
       <arg direction="in" name="plug" type="(so)"/>
       <annotation name="org.qtproject.QtDBus.QtTypeName.In0" value="QSpiObjectReference"/>
@@ -9,11 +32,27 @@
       <annotation name="org.qtproject.QtDBus.QtTypeName.Out0" value="QSpiObjectReference"/>
     </method>
 
+    <!--
+        Unembed:
+        @plug: a string for the unique bus name of the application, and an object path
+        for the application's' root object.
+
+        Unregisters an application from the accesibility registry.  It is not necessary to
+        call this method; the accessibility registry detects when an application
+        disconnects from the bus.
+    -->
     <method name="Unembed">
       <arg direction="in" name="plug" type="(so)"/>
       <annotation name="org.qtproject.QtDBus.QtTypeName.In0" value="QSpiObjectReference"/>
     </method>
 
+    <!--
+        Available:
+        @socket: application and object path for the registry's root object.
+
+        The accessibility registry emits this signal early during startup, when it has
+        registered with the DBus daemon and is available for calls from applications.
+    -->
     <signal name="Available">
       <arg name="socket" type="(so)"/>
       <annotation name="org.qtproject.QtDBus.QtTypeName.In0" value="QSpiObjectReference"/>