SHA256 from file descriptor

[Poul-Henning Kamp]

--------
Dridi Boukelmoune writes:

> My bad, in my mind replying about mmap implied that this was indeed
> about having a convenience functtion to compute the hash of a regular
> file.

Yes, but what do we need that for ?

> Would the attached patch be welcome?

If we have a need, that's pretty much how I would do it.

> Slightly off topic, why have both definitions?
>
>     #define VSHA256_LEN             32
>     #define VSHA256_DIGEST_LENGTH   32

I think I kept it to not break any VMODs which relied on it.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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