function show_vpop_quota ($imp) {
    $quota_html = '';
    $imapuser = $imp['user'];
    // $percent = trim(`sudo /var/vpopmail/bin/vuserinfo -Q $imapuser`);
    $percent = quota_calc($imapuser);
    if (strcmp ($percent, "NOQUOTA")) {
        $class = 'control';
        $quota_html = '<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr><td class="item">'
                      . '<table border="0" cellspacing="2" cellpadding="2" width="100%"><tr><td align="center" class="' . $class . '">'
                      . sprintf("Quota: <strong>%s</strong> used", $percent)
                      . '</td></tr></table></td></tr></table>';
    }
    return $quota_html;
}

function quota_calc ($imapuser) {
    $userquota = trim(`sudo /var/vpopmail/bin/vuserinfo -q $imapuser`);
    if ($userquota == 'NOQUOTA') {
        return ('NOQUOTA');
    }
    $userdir = trim(`sudo /var/vpopmail/bin/vuserinfo -d $imapuser`);
    $userdisk = trim(`sudo /usr/bin/du -sb $userdir`);
    if (preg_match('|(\d+)([kKmMgG])|', $userquota, $matches)) {
        $pf = strtolower($matches[2]);
        if ($pf == 'k') {
            $userquota = $matches[1] * 1024;
        } elseif ($pf == 'm') {
            $userquota = $matches[1] * 1048576;
        } else {
            $userquota = $matches[1] * 1073741824;
        }
    }
    return (sprintf('%.1f%%', (($userdisk * 100.0) / $userquota)));
}