function utf8_to_escaped_sjis($str) {
    $utf8 = preg_split('//u', $str, -1, PREG_SPLIT_NO_EMPTY);
    $sjis = $utf8;
    mb_convert_variables('SJIS', 'UTF-8', $sjis);
    $table = get_html_translation_table(HTML_SPECIALCHARS | ENT_QUOTES);
    foreach ($sjis as $i => &$char) {
        if ($char === '?' && $utf8[$i] !== '?') {
            $char = mb_convert_encoding($utf8[$i], 'HTML-ENTITIES', 'UTF-8');
        } elseif (isset($table[$char])) {
            $char = $table[$char];
        }
    }
    return implode('', $sjis);
}