Commit 9d79b1f564 for qemu.org

commit 9d79b1f5641bdaf726dce3eb8d3df9ef1865ab90
Author: Dongwon Kim <dongwon.kim@intel.com>
Date:   Wed Jul 29 14:44:56 2026 -0700

    ui/gtk: Handle empty notebook state in menu handlers

    When all virtual console tabs are detached (untabified) from the main
    window, the notebook contains no active pages, causing
    gtk_notebook_get_current_page() to return -1.

    Because gtk_notebook_page_num() also returns -1 for any detached VC,
    gd_vc_find_by_page(s, -1) mistakenly matches the first detached
    console. As a result, gd_vc_find_current() incorrectly returns
    a detached VC instead of NULL. Menu actions executed on the empty main
    window then unintentionally operate on that detached VC.

    Fix this by having gd_vc_find_current() explicitly check for page < 0
    and return NULL when the notebook has no active page. In addition, add
    NULL checks for the current VC across relevant UI menu callbacks so
    actions are properly bypassed or reset when no console tab is focused
    in the main window.

    Cc: Daniel P. Berrangé <berrange@redhat.com>
    Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
    Signed-off-by: Dongwon Kim <dongwon.kim@intel.com>
    Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
    Message-ID: <20260729214456.3350-1-dongwon.kim@intel.com>

diff --git a/ui/gtk.c b/ui/gtk.c
index ae28f1fbb8..a194488a0c 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -184,6 +184,11 @@ static VirtualConsole *gd_vc_find_current(GtkDisplayState *s)
     gint page;

     page = gtk_notebook_get_current_page(GTK_NOTEBOOK(s->notebook));
+
+    if (page < 0) {
+        return NULL;
+    }
+
     return gd_vc_find_by_page(s, page);
 }

@@ -1469,7 +1474,10 @@ static void gd_menu_show_tabs(GtkMenuItem *item, void *opaque)
     } else {
         gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), FALSE);
     }
-    gd_update_windowsize(vc);
+
+    if (vc) {
+        gd_update_windowsize(vc);
+    }
 }

 static int gd_vc_notebook_pos(GtkDisplayState *s, VirtualConsole *target)
@@ -1542,6 +1550,10 @@ static void gd_menu_untabify(GtkMenuItem *item, void *opaque)
     GtkDisplayState *s = opaque;
     VirtualConsole *vc = gd_vc_find_current(s);

+    if (!vc) {
+        return;
+    }
+
     if (vc->type == GD_VC_GFX &&
         qemu_console_is_graphic(vc->gfx.dcl.con)) {
         gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item),
@@ -1595,7 +1607,10 @@ static void gd_menu_show_menubar(GtkMenuItem *item, void *opaque)
     } else {
         gtk_widget_hide(s->menu_bar);
     }
-    gd_update_windowsize(vc);
+
+    if (vc) {
+        gd_update_windowsize(vc);
+    }
 }

 static void gd_accel_show_menubar(void *opaque)
@@ -1612,7 +1627,7 @@ static void gd_menu_full_screen(GtkMenuItem *item, void *opaque)
     if (!s->full_screen) {
         gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), FALSE);
         gtk_widget_hide(s->menu_bar);
-        if (vc->type == GD_VC_GFX) {
+        if (vc && vc->type == GD_VC_GFX) {
             gtk_widget_set_size_request(vc->gfx.drawing_area, -1, -1);
         }
         gtk_window_fullscreen(GTK_WINDOW(s->window));
@@ -1625,14 +1640,16 @@ static void gd_menu_full_screen(GtkMenuItem *item, void *opaque)
             gtk_widget_show(s->menu_bar);
         }
         s->full_screen = FALSE;
-        if (vc->type == GD_VC_GFX) {
+        if (vc && vc->type == GD_VC_GFX) {
             vc->gfx.scale_x = vc->gfx.preferred_scale;
             vc->gfx.scale_y = vc->gfx.preferred_scale;
             gd_update_windowsize(vc);
         }
     }

-    gd_update_cursor(vc);
+    if (vc) {
+        gd_update_cursor(vc);
+    }
 }

 static void gd_accel_full_screen(void *opaque)
@@ -1646,6 +1663,10 @@ static void gd_menu_zoom_in(GtkMenuItem *item, void *opaque)
     GtkDisplayState *s = opaque;
     VirtualConsole *vc = gd_vc_find_current(s);

+    if (!vc) {
+        return;
+    }
+
     gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->zoom_fit_item),
                                    FALSE);

@@ -1666,6 +1687,10 @@ static void gd_menu_zoom_out(GtkMenuItem *item, void *opaque)
     GtkDisplayState *s = opaque;
     VirtualConsole *vc = gd_vc_find_current(s);

+    if (!vc) {
+        return;
+    }
+
     gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->zoom_fit_item),
                                    FALSE);

@@ -1683,6 +1708,10 @@ static void gd_menu_zoom_fixed(GtkMenuItem *item, void *opaque)
     GtkDisplayState *s = opaque;
     VirtualConsole *vc = gd_vc_find_current(s);

+    if (!vc) {
+        return;
+    }
+
     vc->gfx.scale_x = vc->gfx.preferred_scale;
     vc->gfx.scale_y = vc->gfx.preferred_scale;

@@ -1694,6 +1723,10 @@ static void gd_menu_zoom_fit(GtkMenuItem *item, void *opaque)
     GtkDisplayState *s = opaque;
     VirtualConsole *vc = gd_vc_find_current(s);

+    if (!vc) {
+        return;
+    }
+
     if (gtk_check_menu_item_get_active(GTK_CHECK_MENU_ITEM(s->zoom_fit_item))) {
         s->free_scale = TRUE;
     } else {
@@ -1807,6 +1840,11 @@ static void gd_menu_grab_input(GtkMenuItem *item, void *opaque)
     VirtualConsole *vc = gd_vc_find_current(s);

     if (gd_is_grab_active(s)) {
+        if (!vc) {
+            gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item),
+                                           FALSE);
+            return;
+        }
         gd_grab_keyboard(vc, "user-request-main-window");
         gd_grab_pointer(vc, "user-request-main-window");
     } else {
@@ -1814,7 +1852,9 @@ static void gd_menu_grab_input(GtkMenuItem *item, void *opaque)
         gd_ungrab_pointer(s);
     }

-    gd_update_cursor(vc);
+    if (vc) {
+        gd_update_cursor(vc);
+    }
 }

 static void gd_change_page(GtkNotebook *nb, gpointer arg1, guint arg2,
@@ -1990,6 +2030,10 @@ static void gd_menu_copy(GtkMenuItem *item, void *opaque)
     GtkDisplayState *s = opaque;
     VirtualConsole *vc = gd_vc_find_current(s);

+    if (!vc) {
+        return;
+    }
+
 #if VTE_CHECK_VERSION(0, 50, 0)
     vte_terminal_copy_clipboard_format(VTE_TERMINAL(vc->vte.terminal),
                                        VTE_FORMAT_TEXT);