bug 2164 fixed: disable automatic rotation if we can't read EXIF data

git-svn-id: http://piwigo.org/svn/trunk@9021 68402e56-0260-453c-a942-63ccdbb3a9ee

admin/include/functions_upload.inc.php

@@ -601,6 +601,11 @@ function get_rotation_angle($source_filepath)
     return null;
   }
   
+  if (!function_exists('exif_read_data'))
+  {
+    return null;
+  }
+
   $rotation = null;
   
   $exif = exif_read_data($source_filepath);