surface: replace map-to-image clone's use of user_data with parent pointer

Removes an another undeclared PLT entry and prevents mixing of user_data
with internal state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

3 files changed, 7 insertions, 14 deletions

diff --git a/src/cairo-image-surface-inline.h b/src/cairo-image-surface-inline.h
index 132d553a..f6bed719 100644
--- a/src/cairo-image-surface-inline.h
+++ b/src/cairo-image-surface-inline.h
@@ -56,6 +56,12 @@ _cairo_image_surface_set_parent (cairo_image_surface_t *image,
     image->parent = parent;
 }
 
+static inline cairo_bool_t
+_cairo_image_surface_is_clone (cairo_image_surface_t *image)
+{
+    return image->parent != NULL;
+}
+
 /**
  * _cairo_surface_is_image:
  * @surface: a #cairo_surface_t
diff --git a/src/cairo-image-surface-private.h b/src/cairo-image-surface-private.h
index 8f7364cb..96601808 100644
--- a/src/cairo-image-surface-private.h
+++ b/src/cairo-image-surface-private.h
@@ -220,9 +220,6 @@ cairo_private cairo_image_surface_t *
 _cairo_image_surface_clone_subimage (cairo_surface_t             *surface,
 				     const cairo_rectangle_int_t *extents);
 
-cairo_private cairo_bool_t
-_cairo_image_surface_is_clone (cairo_image_surface_t *surface);
-
 CAIRO_END_DECLS
 
 #endif /* CAIRO_IMAGE_SURFACE_PRIVATE_H */
diff --git a/src/cairo-image-surface.c b/src/cairo-image-surface.c
index 33170cd3..23e6ca67 100644
--- a/src/cairo-image-surface.c
+++ b/src/cairo-image-surface.c
@@ -1206,8 +1206,6 @@ _cairo_image_analyze_color (cairo_image_surface_t      *image)
     return image->color = CAIRO_IMAGE_IS_COLOR;
 }
 
-static const cairo_user_data_key_t clone_key;
-
 cairo_image_surface_t *
 _cairo_image_surface_clone_subimage (cairo_surface_t             *surface,
 				     const cairo_rectangle_int_t *extents)
@@ -1242,9 +1240,7 @@ _cairo_image_surface_clone_subimage (cairo_surface_t             *surface,
     if (unlikely (status))
 	goto error;
 
-    status = cairo_surface_set_user_data (image, &clone_key, surface, NULL);
-    if (unlikely (status))
-	goto error;
+    _cairo_image_surface_set_parent (to_image_surface (image), surface);
 
     return to_image_surface (image);
 
@@ -1252,9 +1248,3 @@ error:
     cairo_surface_destroy (image);
     return to_image_surface (_cairo_surface_create_in_error (status));
 }
-
-cairo_bool_t
-_cairo_image_surface_is_clone (cairo_image_surface_t *image)
-{
-    return cairo_surface_get_user_data (&image->base, &clone_key) != NULL;
-}