wayland: avoid 0 width/height anchor rectangle

Passing a rectangle with zero width or height to xdg_shell-v6
set_anchor_rect() will cause a protocol error and terminate the client,
as with gedit when pressing the Win key.

Reason for this is because the rectangle used to set the anchor comes
from gtk_text_layout_get_iter_location() which uses the pango layout
width/height, which can be empty if there is not character at the given
location.

Make sure we don't use 0 as width or height as an anchor rectangle to
avoid the protocol error, and compensate the logical position of the
given rectangle if the size is changed, so that the actual position
remains as expected by the client.

https://bugzilla.gnome.org/show_bug.cgi?id=777176

diff --git a/gdk/wayland/gdkwindow-wayland.c b/gdk/wayland/gdkwindow-wayland.c
index 8fce48bf28727b3820c1dd7c9b89bfb51eab7371..d6292885d76bddb61d8ae81a3093c2f35bcc7286 100644 (file)
--- a/gdk/wayland/gdkwindow-wayland.c
+++ b/gdk/wayland/gdkwindow-wayland.c
@@ -2668,6 +2668,34 @@ gdk_window_wayland_move_resize (GdkWindow *window,
     gdk_wayland_window_maybe_configure (window, width, height, impl->scale);
 }
 
+/* Avoid zero width/height as this is a protocol error */
+static void
+sanitize_anchor_rect (GdkWindow    *window,
+                      GdkRectangle *rect)
+{
+  gint original_width = rect->width;
+  gint original_height = rect->height;
+  GdkWindow *parent = get_popup_parent (window);
+
+  rect->width  = MAX (1, rect->width);
+  rect->height = MAX (1, rect->height);
+  rect->x -= rect->width - original_width;
+  rect->y -= rect->height - original_height;
+
+  /* Make sure the anchor rectangle does not extend outside the window
+   * geometry of the parent surface.
+   */
+  if (parent)
+    {
+      GdkRectangle geometry;
+
+      /* The rectangle is relative to the parent window geometry */
+      gdk_wayland_window_get_window_geometry (parent, &geometry);
+      rect->x = CLAMP (rect->x, 0, geometry.width);
+      rect->y = CLAMP (rect->y, 0, geometry.height);
+    }
+}
+
 static void
 gdk_window_wayland_move_to_rect (GdkWindow          *window,
                                  const GdkRectangle *rect,
@@ -2680,6 +2708,8 @@ gdk_window_wayland_move_to_rect (GdkWindow          *window,
   GdkWindowImplWayland *impl = GDK_WINDOW_IMPL_WAYLAND (window->impl);
 
   impl->pending_move_to_rect.rect = *rect;
+  sanitize_anchor_rect (window, &impl->pending_move_to_rect.rect);
+
   impl->pending_move_to_rect.rect_anchor = rect_anchor;
   impl->pending_move_to_rect.window_anchor = window_anchor;
   impl->pending_move_to_rect.anchor_hints = anchor_hints;