path: root/0002-local-display-factory-Fix-user-switching-with-legacy.patch

From 510566699c480226b189215c6222f7e72979baf8 Mon Sep 17 00:00:00 2001
From: Ray Strode <rstrode@redhat.com>
Date: Wed, 22 May 2024 14:05:20 -0400
Subject: [PATCH 2/2] local-display-factory: Fix user switching with legacy
 xorg

legacy-xorg sessions currently fail to completely user switch.

This is because the wrong session types are attached to the generated
login screen display.

This commit refactors the code so the same session types are used for
user switching as are used for the initial login.
---
 daemon/gdm-local-display-factory.c | 78 +++++++++++++++++++++---------
 1 file changed, 54 insertions(+), 24 deletions(-)

diff --git a/daemon/gdm-local-display-factory.c b/daemon/gdm-local-display-factory.c
index 7447b985a..4efbf0a6d 100644
--- a/daemon/gdm-local-display-factory.c
+++ b/daemon/gdm-local-display-factory.c
@@ -331,118 +331,131 @@ gdm_local_display_factory_get_session_types (GdmLocalDisplayFactory *factory,
         if (display_server_enabled (factory, fallback_display_server))
                 g_ptr_array_add (session_types_array, (gpointer) get_session_type_for_display_server (factory, fallback_display_server));
 
         if (session_types_array->len == 0)
                 return NULL;
 
         g_ptr_array_add (session_types_array, NULL);
 
         session_types = g_strdupv ((char **) session_types_array->pdata);
 
         return session_types;
 }
 
 static void
 on_display_disposed (GdmLocalDisplayFactory *factory,
                      GdmDisplay             *display)
 {
         g_debug ("GdmLocalDisplayFactory: Display %p disposed", display);
 }
 
 static void
 store_display (GdmLocalDisplayFactory *factory,
                GdmDisplay             *display)
 {
         GdmDisplayStore *store;
 
         store = gdm_display_factory_get_display_store (GDM_DISPLAY_FACTORY (factory));
         gdm_display_store_add (store, display);
 }
 
+static GdmDisplay *
+create_legacy_xorg_display (GdmLocalDisplayFactory *factory)
+{
+        guint32 display_number;
+        const char *session_types[] = { "x11", NULL };
+        GdmDisplay *display;
+
+        display_number = take_next_display_number (factory);
+
+        g_debug ("GdmLocalDisplayFactory: Creating legacy Xorg display at :%d", display_number);
+
+        display = gdm_legacy_display_new (display_number);
+        g_object_set (G_OBJECT (display),
+                      "session-type", session_types[0],
+                      "supported-session-types", session_types,
+                      NULL);
+
+        return display;
+}
+
 /*
   Example:
   dbus-send --system --dest=org.gnome.DisplayManager \
   --type=method_call --print-reply --reply-timeout=2000 \
   /org/gnome/DisplayManager/Manager \
   org.gnome.DisplayManager.Manager.GetDisplays
 */
 gboolean
 gdm_local_display_factory_create_transient_display (GdmLocalDisplayFactory *factory,
                                                     char                  **id,
                                                     GError                **error)
 {
         gboolean         ret;
         GdmDisplay      *display = NULL;
         gboolean         is_initial = FALSE;
         const char      *session_type;
         g_autofree gchar *preferred_display_server = NULL;
 
         g_return_val_if_fail (GDM_IS_LOCAL_DISPLAY_FACTORY (factory), FALSE);
 
         ret = FALSE;
 
         g_debug ("GdmLocalDisplayFactory: Creating transient display");
 
         preferred_display_server = get_preferred_display_server (factory);
 
 #ifdef ENABLE_USER_DISPLAY_SERVER
         if (g_strcmp0 (preferred_display_server, "wayland") == 0 ||
             g_strcmp0 (preferred_display_server, "xorg") == 0) {
                 g_auto(GStrv) session_types = NULL;
 
                 session_types = gdm_local_display_factory_get_session_types (factory, FALSE);
 
                 if (session_types == NULL) {
                         g_set_error_literal (error,
                                              GDM_DISPLAY_ERROR,
                                              GDM_DISPLAY_ERROR_GENERAL,
                                              "Both Wayland and Xorg are unavailable");
                         return FALSE;
                 }
 
                 display = gdm_local_display_new ();
                 g_object_set (G_OBJECT (display),
                               "session-type", session_types[0],
                               "supported-session-types", session_types,
                               NULL);
                 is_initial = TRUE;
         }
 #endif
-        if (g_strcmp0 (preferred_display_server, "legacy-xorg") == 0) {
-                if (display == NULL) {
-                        guint32 num;
-
-                        num = take_next_display_number (factory);
-
-                        display = gdm_legacy_display_new (num);
-                }
-        }
+        if (g_strcmp0 (preferred_display_server, "legacy-xorg") == 0)
+                display = create_legacy_xorg_display (factory);
 
         if (display == NULL) {
                 g_set_error_literal (error,
                                      GDM_DISPLAY_ERROR,
                                      GDM_DISPLAY_ERROR_GENERAL,
                                      "Invalid preferred display server configured");
                 return FALSE;
         }
 
         g_object_set (display,
                       "seat-id", "seat0",
                       "allow-timed-login", FALSE,
                       "is-initial", is_initial,
                       NULL);
 
         store_display (factory, display);
 
         if (! gdm_display_manage (display)) {
                 display = NULL;
                 goto out;
         }
 
         if (! gdm_display_get_id (display, id, NULL)) {
                 display = NULL;
                 goto out;
         }
 
         ret = TRUE;
  out:
         /* ref either held by store or not at all */
@@ -591,70 +604,87 @@ on_display_status_changed (GdmDisplay             *display,
         case GDM_DISPLAY_WAITING_TO_FINISH:
                 break;
         default:
                 g_assert_not_reached ();
                 break;
         }
 
         g_free (seat_id);
         g_free (session_type);
         g_free (session_class);
 }
 
 static gboolean
 lookup_by_seat_id (const char *id,
                    GdmDisplay *display,
                    gpointer    user_data)
 {
         const char *looking_for = user_data;
         char *current;
         gboolean res;
 
         g_object_get (G_OBJECT (display), "seat-id", &current, NULL);
 
         res = g_strcmp0 (current, looking_for) == 0;
 
         g_free(current);
 
         return res;
 }
 
+static gboolean
+lookup_initial_display (const char *id,
+		        GdmDisplay *display)
+{
+        gboolean is_initial = FALSE;
+        int status;
+
+        status = gdm_display_get_status (display);
+
+        if (status != GDM_DISPLAY_PREPARED && status != GDM_DISPLAY_MANAGED)
+                return FALSE;
+
+        g_object_get (G_OBJECT (display), "is-initial", &is_initial, NULL);
+
+        return is_initial;
+}
+
 static gboolean
 lookup_prepared_display_by_seat_id (const char *id,
                                     GdmDisplay *display,
                                     gpointer    user_data)
 {
         int status;
 
         status = gdm_display_get_status (display);
 
-        if (status != GDM_DISPLAY_PREPARED)
+        if (status != GDM_DISPLAY_PREPARED && status != GDM_DISPLAY_MANAGED)
                 return FALSE;
 
         return lookup_by_seat_id (id, display, user_data);
 }
 
 #ifdef HAVE_UDEV
 static gboolean
 udev_is_settled (GdmLocalDisplayFactory *factory)
 {
         g_autoptr (GUdevEnumerator) enumerator = NULL;
         GList *devices;
         GList *node;
 
         gboolean is_settled = FALSE;
 
         if (factory->seat0_has_platform_graphics) {
                 g_debug ("GdmLocalDisplayFactory: udev settled, platform graphics enabled.");
                 return TRUE;
         }
 
         if (factory->seat0_has_boot_up_graphics) {
                 g_debug ("GdmLocalDisplayFactory: udev settled, boot up graphics available.");
                 return TRUE;
         }
 
         if (factory->seat0_graphics_check_timed_out) {
                 g_debug ("GdmLocalDisplayFactory: udev timed out, proceeding anyway.");
                 return TRUE;
         }
 
@@ -834,115 +864,115 @@ ensure_display_for_seat (GdmLocalDisplayFactory *factory,
                                         /* It is not yet time to force X11 fallback. */
                                         g_debug ("GdmLocalDisplayFactory: seat0 display requested when there is no graphics support before graphics check timeout.");
                                 }
 
                                 return;
                         }
 
                         g_debug ("GdmLocalDisplayFactory: Assuming we can use seat0 for X11 even though system says it doesn't support graphics!");
                         g_debug ("GdmLocalDisplayFactory: This might indicate an issue where the framebuffer device is not tagged as master-of-seat in udev.");
                         seat_supports_graphics = TRUE;
                         wayland_enabled = FALSE;
                         g_strfreev (session_types);
                         session_types = g_strdupv ((char **) legacy_session_types);
                 } else {
                         g_clear_handle_id (&factory->seat0_graphics_check_timeout_id, g_source_remove);
                 }
         }
 
         if (!seat_supports_graphics)
                 return;
 
         if (session_types != NULL)
                 g_debug ("GdmLocalDisplayFactory: %s login display for seat %s requested",
                          session_types[0], seat_id);
         else if (g_strcmp0 (preferred_display_server, "legacy-xorg") == 0)
                 g_debug ("GdmLocalDisplayFactory: Legacy Xorg login display for seat %s requested",
                          seat_id);
 
         store = gdm_display_factory_get_display_store (GDM_DISPLAY_FACTORY (factory));
 
-        if (is_seat0)
-                display = gdm_display_store_find (store, lookup_prepared_display_by_seat_id, (gpointer) seat_id);
-        else
+        if (is_seat0) {
+		display = gdm_display_store_find (store, lookup_prepared_display_by_seat_id, (gpointer) seat_id);
+		if (display != NULL && g_strcmp0 (preferred_display_server, "legacy-xorg") == 0) {
+                        GdmDisplay *initial_display = NULL;
+
+                        initial_display = gdm_display_store_find (store, lookup_initial_display, (gpointer) NULL);
+
+			if (initial_display == NULL)
+				display = NULL;
+		}
+	} else {
                 display = gdm_display_store_find (store, lookup_by_seat_id, (gpointer) seat_id);
+	}
 
         /* Ensure we don't create the same display more than once */
         if (display != NULL) {
                 g_debug ("GdmLocalDisplayFactory: display already created");
                 return;
         }
 
         /* If we already have a login window, switch to it */
         if (gdm_get_login_window_session_id (seat_id, &login_session_id)) {
                 GdmDisplay *display;
 
                 display = gdm_display_store_find (store,
                                                   lookup_by_session_id,
                                                   (gpointer) login_session_id);
                 if (display != NULL &&
                     (gdm_display_get_status (display) == GDM_DISPLAY_MANAGED ||
                      gdm_display_get_status (display) == GDM_DISPLAY_WAITING_TO_FINISH)) {
                         g_object_set (G_OBJECT (display), "status", GDM_DISPLAY_MANAGED, NULL);
                         g_debug ("GdmLocalDisplayFactory: session %s found, activating.",
                                  login_session_id);
                         gdm_activate_session_by_id (factory->connection, seat_id, login_session_id);
                         return;
                 }
         }
 
         g_debug ("GdmLocalDisplayFactory: Adding display on seat %s", seat_id);
 
 #ifdef ENABLE_USER_DISPLAY_SERVER
         if (g_strcmp0 (preferred_display_server, "wayland") == 0 ||
             g_strcmp0 (preferred_display_server, "xorg") == 0) {
                 if (is_seat0) {
                         display = gdm_local_display_new ();
                         g_object_set (G_OBJECT (display),
                                       "session-type", session_types[0],
                                       "supported-session-types", session_types,
                                       NULL);
                 }
         }
 #endif
 
-        if (display == NULL) {
-                guint32 num;
-
-                num = take_next_display_number (factory);
-
-                display = gdm_legacy_display_new (num);
-                g_object_set (G_OBJECT (display),
-                              "session-type", legacy_session_types[0],
-                              "supported-session-types", legacy_session_types,
-                              NULL);
-        }
+        if (display == NULL)
+                display = create_legacy_xorg_display (factory);
 
         g_object_set (display, "seat-id", seat_id, NULL);
         g_object_set (display, "is-initial", is_seat0, NULL);
 
         store_display (factory, display);
 
         /* let store own the ref */
         g_object_unref (display);
 
         if (! gdm_display_manage (display)) {
                 gdm_display_unmanage (display);
         }
 
         return;
 }
 
 static void
 delete_display (GdmLocalDisplayFactory *factory,
                 const char             *seat_id) {
 
         GdmDisplayStore *store;
 
         g_debug ("GdmLocalDisplayFactory: Removing used_display_numbers on seat %s", seat_id);
 
         store = gdm_display_factory_get_display_store (GDM_DISPLAY_FACTORY (factory));
         gdm_display_store_foreach_remove (store, lookup_by_seat_id, (gpointer) seat_id);
 }
 
 static gboolean
 gdm_local_display_factory_sync_seats (GdmLocalDisplayFactory *factory)
-- 
2.40.0