1 files changed, 53 insertions, 0 deletions
diff --git a/app/xcf/xcf-utils.c b/app/xcf/xcf-utils.c
new file mode 100644
index 0000000..726cad2
--- /dev/null
+++ b/app/xcf/xcf-utils.c
@@ -0,0 +1,53 @@
+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include <cairo.h>
+#include <gegl.h>
+#include <gdk-pixbuf/gdk-pixbuf.h>
+
+#include "xcf-utils.h"
+
+
+gboolean
+xcf_data_is_zero (const void *data,
+                  gint        size)
+{
+  const guint8  *data8;
+  const guint64 *data64;
+
+  for (data8 = data; size > 0 && (guintptr) data8 % 8 != 0; data8++, size--)
+    {
+      if (*data8)
+        return FALSE;
+    }
+
+  for (data64 = (gpointer) data8; size >= 8; data64++, size -= 8)
+    {
+      if (*data64)
+        return FALSE;
+    }
+
+  for (data8 = (gpointer) data64; size > 0; data8++, size--)
+    {
+      if (*data8)
+        return FALSE;
+    }
+
+  return TRUE;
+}