Files::escape PHP Method

    function escape($filename)
    {
        return preg_replace('/[^\\w\\._]/', '_', $filename);
    }

 /**
  * Copy a file from source to destination. If unique == true, then if
  * the destination exists, it will be renamed by appending an increamenting 
  * counting number.
  * @param string $source where the file is from, full path to the files required
  * @param string $destination_file name of the new file, just the filename
  * @param string $destination_dir where the files, just the destination dir,
  * e.g., /www/html/gallery/
  * @param boolean $unique create unique destination file if true.
  * @return string the new copied filename, else error if anything goes bad.
  */
 function copyFile($source, $destination_dir, $destination_file, $unique = true)
 {
     if (!(file_exists($source) && is_file($source))) {
         return FILE_ERROR_NO_SOURCE;
     }
     $destination_dir = Files::fixPath($destination_dir);
     if (!is_dir($destination_dir)) {
         return FILE_ERROR_DST_DIR_FAILED;
     }
     $filename = Files::escape($destination_file);
     if ($unique) {
         $dotIndex = strrpos($destination_file, '.');
         $ext = '';
         if (is_int($dotIndex)) {
             $ext = substr($destination_file, $dotIndex);
             $base = substr($destination_file, 0, $dotIndex);
         }
         $counter = 0;
         while (is_file($destination_dir . $filename)) {
             $counter++;
             $filename = $base . '_' . $counter . $ext;
         }
     }
     if (!copy($source, $destination_dir . $filename)) {
         return FILE_ERROR_COPY_FAILED;
     }
     //verify that it copied, new file must exists
     if (is_file($destination_dir . $filename)) {
         return $filename;
     } else {
         return FILE_ERROR_COPY_FAILED;
     }
 }