refactored alias.c heavily especially substituted the loop-based alias_expand() with a recursive approach. Now alias_expand() wraps alias_one() which recursively expands aliases. In principle the ``data processing'' is the same but now it's clearer structured and thus easier to understand IMO. The loop might have been faster but I don't care for speed -- the most simple solution is the best. It's fast enough, that is sufficient.

void hmac_md5(
	unsigned char* text,   /* pointer to the message */
	int textlen,           /* length of the message */
	unsigned char* key,    /* pointer to the authentication key */
	int keylen,            /* length of the key */
	unsigned char* digest  /* pointer to allocated memory to store the computed HMAC */
);