portal: Introduce implementation stub

From now on nautilus claims to implement the FileChooser portal.

For now it's a lie. But the next few commits will make it true.

data/meson.build

@@ -146,5 +146,15 @@ if appstreamcli.found()
   )
 endif
 
+portal_impl_conf = configuration_data()
+portal_impl_conf.set('appid', application_id)
+
+configure_file(
+  input: 'nautilus.portal.in',
+  output: 'nautilus.portal',
+  configuration: portal_impl_conf,
+  install_dir: datadir / 'xdg-desktop-portal' / 'portals',
+)
+
 subdir('ontology')
 subdir('tracker')

data/nautilus.portal.in

@@ -0,0 +1,4 @@
+[portal]
+DBusName=@appid@
+Interfaces=org.freedesktop.impl.portal.FileChooser;
+UseIn=gnome

src/meson.build

@@ -210,6 +210,8 @@ libnautilus_sources = [
   'nautilus-module.h',
   'nautilus-monitor.c',
   'nautilus-monitor.h',
+  'nautilus-portal.c',
+  'nautilus-portal.h',
   'nautilus-progress-info.c',
   'nautilus-progress-info.h',
   'nautilus-progress-info-manager.c',

src/nautilus-application.c

@@ -54,6 +54,7 @@
 #include "nautilus-global-preferences.h"
 #include "nautilus-icon-info.h"
 #include "nautilus-module.h"
+#include "nautilus-portal.h"
 #include "nautilus-preferences-window.h"
 #include "nautilus-previewer.h"
 #include "nautilus-progress-persistence-handler.h"
@@ -73,6 +74,7 @@ typedef struct
     NautilusProgressPersistenceHandler *progress_handler;
     NautilusDBusManager *dbus_manager;
     NautilusFreedesktopDBus *fdb_manager;
+    NautilusPortal *portal_implementation;
 
     NautilusBookmarkList *bookmark_list;
 
@@ -1203,6 +1205,13 @@ nautilus_application_dbus_register (GApplication     *app,
         return FALSE;
     }
 
+    priv->portal_implementation = nautilus_portal_new ();
+    if (g_strcmp0 (g_getenv ("RUNNING_TESTS"), "TRUE") != 0 &&
+        !nautilus_portal_register (priv->portal_implementation, connection, error))
+    {
+        return FALSE;
+    }
+
     priv->search_provider = nautilus_shell_search_provider_new ();
     if (!nautilus_shell_search_provider_register (priv->search_provider, connection, error))
     {
@@ -1235,6 +1244,12 @@ nautilus_application_dbus_unregister (GApplication    *app,
         g_clear_object (&priv->fdb_manager);
     }
 
+    if (priv->portal_implementation != NULL)
+    {
+        nautilus_portal_unregister (priv->portal_implementation);
+        g_clear_object (&priv->portal_implementation);
+    }
+
     if (priv->search_provider)
     {
         nautilus_shell_search_provider_unregister (priv->search_provider);

src/nautilus-portal.c

@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2024 GNOME Foundation Inc.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * Original Author: António Fernandes <antoniof@gnome.org>
+ */
+
+#define G_LOG_DOMAIN "nautilus-dbus"
+
+#include "nautilus-portal.h"
+
+#include <config.h>
+#include <xdp-gnome/request.h>
+#include <xdp-gnome/xdg-desktop-portal-dbus.h>
+
+#define DESKTOP_PORTAL_OBJECT_PATH "/org/freedesktop/portal/desktop"
+
+struct _NautilusPortal
+{
+    GObject parent;
+
+    XdpImplFileChooser *implementation_skeleton;
+};
+
+G_DEFINE_TYPE (NautilusPortal, nautilus_portal, G_TYPE_OBJECT);
+
+static void
+nautilus_portal_dispose (GObject *object)
+{
+    NautilusPortal *self = (NautilusPortal *) object;
+
+    g_signal_handlers_disconnect_by_data (self->implementation_skeleton, self);
+    g_clear_object (&self->implementation_skeleton);
+
+    G_OBJECT_CLASS (nautilus_portal_parent_class)->dispose (object);
+}
+
+static void
+nautilus_portal_class_init (NautilusPortalClass *klass)
+{
+    GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+    object_class->dispose = nautilus_portal_dispose;
+}
+
+static void
+nautilus_portal_init (NautilusPortal *self)
+{
+    self->implementation_skeleton = xdp_impl_file_chooser_skeleton_new ();
+}
+
+NautilusPortal *
+nautilus_portal_new (void)
+{
+    return g_object_new (NAUTILUS_TYPE_PORTAL, NULL);
+}
+
+gboolean
+nautilus_portal_register (NautilusPortal   *self,
+                          GDBusConnection  *connection,
+                          GError          **error)
+{
+    if (!g_dbus_interface_skeleton_export (G_DBUS_INTERFACE_SKELETON (self->implementation_skeleton),
+                                           connection,
+                                           DESKTOP_PORTAL_OBJECT_PATH,
+                                           error))
+    {
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+void
+nautilus_portal_unregister (NautilusPortal *self)
+{
+    g_dbus_interface_skeleton_unexport (G_DBUS_INTERFACE_SKELETON (self->implementation_skeleton));
+}

src/nautilus-portal.h

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2024 GNOME Foundation Inc.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * Original Author: António Fernandes <antoniof@gnome.org>
+ */
+
+#pragma once
+
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+#define NAUTILUS_TYPE_PORTAL (nautilus_portal_get_type())
+
+G_DECLARE_FINAL_TYPE (NautilusPortal, nautilus_portal, NAUTILUS, PORTAL, GObject)
+
+NautilusPortal * nautilus_portal_new (void);
+
+void nautilus_portal_unregister (NautilusPortal *self);
+gboolean nautilus_portal_register (NautilusPortal   *self,
+                                   GDBusConnection  *connection,
+                                   GError          **error);
+
+G_END_DECLS