is readable recursively. Check all sub directories and files readable
<?php
function is_readable_r($dir) {
 if (is_dir($dir)) {
 if(is_readable($dir)){
 $objects = scandir($dir);
 foreach ($objects as $object) {
 if ($object != "." && $object != "..") {
 if (!is_readable_r($dir."/".$object)) return false;
 else continue;
 }
 } 
 return true; 
 }else{
 return false;
 }
 
 }else if(file_exists($dir)){
 return (is_readable($dir));
 
 }
}
?>