Make backend-specific function set a surface error on type mismatch.

If any backend-specific, surface-modifying function is called with
the wrong surface type we set an error on that surface.

4 files changed, 19 insertions, 11 deletions

diff --git a/src/cairo-surface.c b/src/cairo-surface.c
index 9a15db4f6..f905dfd05 100644
--- a/src/cairo-surface.c
+++ b/src/cairo-surface.c
@@ -108,7 +108,7 @@ const cairo_surface_t _cairo_surface_nil_read_error = {
  * breakpoint in _cairo_error() to generate a stack trace for when the
  * user causes cairo to detect an error.
  **/
-static void
+void
 _cairo_surface_set_error (cairo_surface_t *surface,
 			  cairo_status_t status)
 {
diff --git a/src/cairo-xcb-surface.c b/src/cairo-xcb-surface.c
index 78eafc0fa..1e90f10e0 100644
--- a/src/cairo-xcb-surface.c
+++ b/src/cairo-xcb-surface.c
@@ -1291,9 +1291,10 @@ cairo_xcb_surface_set_size (cairo_surface_t *surface,
 {
     cairo_xcb_surface_t *xcb_surface = (cairo_xcb_surface_t *)surface;
 
-    /* XXX: How do we want to handle this error case? */
-    if (! _cairo_surface_is_xcb (surface))
+    if (! _cairo_surface_is_xcb (surface)) {
+	_cairo_surface_set_error (surface, CAIRO_STATUS_SURFACE_TYPE_MISMATCH);
 	return;
+    }
 
     xcb_surface->width = width;
     xcb_surface->height = height;
diff --git a/src/cairo-xlib-surface.c b/src/cairo-xlib-surface.c
index 91bb178a1..3245af6cc 100644
--- a/src/cairo-xlib-surface.c
+++ b/src/cairo-xlib-surface.c
@@ -1947,18 +1947,20 @@ cairo_xlib_surface_create_with_xrender_format (Display		    *dpy,
  * this function on a surface created for a Pixmap.
  **/
 void
-cairo_xlib_surface_set_size (cairo_surface_t *surface,
+cairo_xlib_surface_set_size (cairo_surface_t *abstract_surface,
 			     int              width,
 			     int              height)
 {
-    cairo_xlib_surface_t *xlib_surface = (cairo_xlib_surface_t *)surface;
+    cairo_xlib_surface_t *surface = (cairo_xlib_surface_t *) abstract_surface;
 
-    /* XXX: How do we want to handle this error case? */
-    if (! _cairo_surface_is_xlib (surface))
+    if (! _cairo_surface_is_xlib (abstract_surface)) {
+	_cairo_surface_set_error (abstract_surface,
+				  CAIRO_STATUS_SURFACE_TYPE_MISMATCH);
 	return;
+    }
 
-    xlib_surface->width = width;
-    xlib_surface->height = height;
+    surface->width = width;
+    surface->height = height;
 }
 /**
  * cairo_xlib_surface_set_drawable:
@@ -1982,9 +1984,10 @@ cairo_xlib_surface_set_drawable (cairo_surface_t   *abstract_surface,
 {
     cairo_xlib_surface_t *surface = (cairo_xlib_surface_t *)abstract_surface;
 
-    /* XXX: How do we want to handle this error case? */
-    if (! _cairo_surface_is_xlib (abstract_surface))
+    if (! _cairo_surface_is_xlib (abstract_surface)) {
+	_cairo_surface_set_error (abstract_surface, CAIRO_STATUS_SURFACE_TYPE_MISMATCH);
 	return;
+    }
 
     /* XXX: and what about this case? */
     if (surface->owns_pixmap)
diff --git a/src/cairoint.h b/src/cairoint.h
index 65b482ff9..cfa8b7d23 100644
--- a/src/cairoint.h
+++ b/src/cairoint.h
@@ -1607,6 +1607,10 @@ extern const cairo_private cairo_surface_t _cairo_surface_nil;
 extern const cairo_private cairo_surface_t _cairo_surface_nil_read_error;
 extern const cairo_private cairo_surface_t _cairo_surface_nil_file_not_found;
 
+cairo_private void
+_cairo_surface_set_error (cairo_surface_t	*surface,
+			  cairo_status_t	 status);
+
 cairo_private cairo_surface_t *
 _cairo_surface_create_similar_scratch (cairo_surface_t *other,
 				       cairo_content_t	content,