Index: kernel/generic/src/lib/string.c
===================================================================
--- kernel/generic/src/lib/string.c	(revision 67a88c34de6b29d84b4ea8c0f06dfa98cbcf09bd)
+++ kernel/generic/src/lib/string.c	(revision 4ccdcf6996a47d3c30ec7072330cc3ed9b6b7737)
@@ -43,4 +43,73 @@
 #include <console/kconsole.h>
 
+/** Decode a single UTF-8 character from a NULL-terminated string.
+ *
+ * Decode a single UTF-8 character from a plain char NULL-terminated
+ * string. Decoding starts at @index and this index is incremented
+ * if the current UTF-8 string is encoded in more than a single byte.
+ *
+ * @param str   Plain character NULL-terminated string.
+ * @param index Index (counted in plain characters) where to start
+ *              the decoding.
+ *
+ * @return Decoded character in UTF-32 or '?' if the encoding is wrong.
+ *
+ */
+wchar_t utf8_decode(const char *str, index_t *index)
+{
+	uint8_t c1;           /* First plain character from str */
+	uint8_t c2;           /* Second plain character from str */
+	uint8_t c3;           /* Third plain character from str */
+	uint8_t c4;           /* Fourth plain character from str */
+	
+	c1 = (uint8_t) str[*index];
+	
+	if ((c1 & 0x80) == 0) {
+		/* Plain ASCII (code points 0 .. 127) */
+		return (wchar_t) c1;
+	} else if ((c1 & 0xe0) == 0xc0) {
+		/* Code points 128 .. 2047 */
+		c2 = (uint8_t) str[*index + 1];
+		if ((c2 & 0xc0) == 0x80) {
+			(*index)++;
+			return ((wchar_t) ((c1 & 0x1f) << 6) | (c2 & 0x3f));
+		} else
+			return ((wchar_t) '?');
+	} else if ((c1 & 0xf0) == 0xe0) {
+		/* Code points 2048 .. 65535 */
+		c2 = (uint8_t) str[*index + 1];
+		if ((c2 & 0xc0) == 0x80) {
+			(*index)++;
+			c3 = (uint8_t) str[*index + 1];
+			if ((c3 & 0xc0) == 0x80) {
+				(*index)++;
+				return ((wchar_t) ((c1 & 0x0f) << 12) | ((c2 & 0x3f) << 6) | (c3 & 0x3f));
+			} else
+				return ((wchar_t) '?');
+		} else
+			return ((wchar_t) '?');
+	} else if ((c1 & 0xf8) == 0xf0) {
+		/* Code points 65536 .. 1114111 */
+		c2 = (uint8_t) str[*index + 1];
+		if ((c2 & 0xc0) == 0x80) {
+			(*index)++;
+			c3 = (uint8_t) str[*index + 1];
+			if ((c3 & 0xc0) == 0x80) {
+				(*index)++;
+				c4 = (uint8_t) str[*index + 1];
+				if ((c4 & 0xc0) == 0x80) {
+					(*index)++;
+					return ((wchar_t) ((c1 & 0x07) << 18) | ((c2 & 0x3f) << 12) | ((c3 & 0x3f) << 6) | (c4 & 0x3f));
+				} else
+					return ((wchar_t) '?');
+			} else
+				return ((wchar_t) '?');
+		} else
+			return ((wchar_t) '?');
+	}
+	
+	return ((wchar_t) '?');
+}
+
 /** Return number of characters in a string.
  *