TYPO3 / TYPO3.CMS

            // parse_url could return an array without the key "host", the empty check works better than strict check

            if (empty($url_parts['host'])) {

                $url_parts['host'] = GeneralUtility::getIndpEnv('HTTP_HOST');

                if ($code[0] === '/') {

                    $code = GeneralUtility::getIndpEnv('TYPO3_REQUEST_HOST') . $code;

                } else {

                    $code = GeneralUtility::getIndpEnv('TYPO3_REQUEST_DIR') . $code;

                }

                $checkBaseTag = false;

            } else {

                $checkBaseTag = true;

    {

        $uI = parse_url($path);

        // relative to HOST

        if ($path[0] === '/') {

            $path = self::getIndpEnv('TYPO3_REQUEST_HOST') . $path;

        } elseif (!$uI['scheme']) {

            // No scheme either

            $path = self::getIndpEnv('TYPO3_REQUEST_DIR') . $path;

        }

        return $path;

    }