LionsAd / service_container

          }

        }

      }

      elseif ($start < 0) {

        // Count all the characters except continuation bytes from the end

        // until we have found abs($start) characters.

        $start = abs($start);

        $bytes = $strlen; $chars = 0;

        while ($bytes > 0 && $chars < $start) {

          $bytes--;

          $c = ord($text[$bytes]);

          if ($c < 0x80 || $c >= 0xC0) {

            $chars++;

          }

        }

      }

      $istart = $bytes;

      // Find the ending byte offset.

          $iend--;

        }

      }

      elseif ($length < 0) {

        // Count all the characters except continuation bytes from the end

        // until we have found abs($start) characters, then backtrace one byte.

        $length = abs($length);

        $iend = $strlen; $chars = 0;

        while ($iend > 0 && $chars < $length) {

          $iend--;

          $c = ord($text[$iend]);

          if ($c < 0x80 || $c >= 0xC0) {

            $chars++;

          }

        }

        // Backtrace one byte if we are not at the beginning of the string.

        if ($iend > 0) {

          $iend--;

        }

      }

      else {

        // $length == 0, return an empty string.

        return '';