efi/libstub: Add UTF-8 decoding to efi_puts

		       output_string, str);

}

static

u32 utf8_to_utf32(const u8 **s8)

{

	u32 c32;

	u8 c0, cx;

	size_t clen, i;

	c0 = cx = *(*s8)++;

	/*

	 * The position of the most-significant 0 bit gives us the length of

	 * a multi-octet encoding.

	 */

	for (clen = 0; cx & 0x80; ++clen)

		cx <<= 1;

	/*

	 * If the 0 bit is in position 8, this is a valid single-octet

	 * encoding. If the 0 bit is in position 7 or positions 1-3, the

	 * encoding is invalid.

	 * In either case, we just return the first octet.

	 */

	if (clen < 2 || clen > 4)

		return c0;

	/* Get the bits from the first octet. */

	c32 = cx >> clen--;

	for (i = 0; i < clen; ++i) {

		/* Trailing octets must have 10 in most significant bits. */

		cx = (*s8)[i] ^ 0x80;

		if (cx & 0xc0)

			return c0;

		c32 = (c32 << 6) | cx;

	}

	/*

	 * Check for validity:

	 * - The character must be in the Unicode range.

	 * - It must not be a surrogate.

	 * - It must be encoded using the correct number of octets.

	 */

	if (c32 > 0x10ffff ||

	    (c32 & 0xf800) == 0xd800 ||

	    clen != (c32 >= 0x80) + (c32 >= 0x800) + (c32 >= 0x10000))

		return c0;

	*s8 += clen;

	return c32;

}

void efi_puts(const char *str)

{

	efi_char16_t buf[128];

	size_t pos = 0, lim = ARRAY_SIZE(buf);

	const u8 *s8 = (const u8 *)str;

	u32 c32;

	while (*str) {

		if (*str == '\n')

	while (*s8) {

		if (*s8 == '\n')

			buf[pos++] = L'\r';

		/* Cast to unsigned char to avoid sign-extension */

		buf[pos++] = (unsigned char)(*str++);

		if (*str == '\0' || pos >= lim - 2) {

		c32 = utf8_to_utf32(&s8);

		if (c32 < 0x10000) {

			/* Characters in plane 0 use a single word. */

			buf[pos++] = c32;

		} else {

			/*

			 * Characters in other planes encode into a surrogate

			 * pair.

			 */

			buf[pos++] = (0xd800 - (0x10000 >> 10)) + (c32 >> 10);

			buf[pos++] = 0xdc00 + (c32 & 0x3ff);

		}

		if (*s8 == '\0' || pos >= lim - 2) {

			buf[pos] = L'\0';

			efi_char16_puts(buf);

			pos = 0;