gcry_md_read fails with HASH_NONE

[Glenn McGrath]

I have a simple function which calculates the hash of a file, if the
algorithm is set to HASH_NONE then it gives this error.

Ohhhh jeeee: ... this is a bug (md.c:668:md_read)

Im using version 1.1.12

It is a pretty pointless thing to try and compute or display a hash that
doesnt exist, but it would be convenient if it would return NULL or
something.

gcry_md_write works fine, so i assume it really is a bug, i havent
looked into the gcrypt code.



Glenn