Minor cleanup

[sjaeckel]

Minor cleanup&lil'feature PR

The only thing really worth a review is the newly introduced copy_or_zeromem()

The rest is just cosmetics.

Reviews are as always very welcome!

[karel-m]

Ad copy_or_zeromem

• I am not sure if we want it to be part of public API
• if it'll will be part of public API then the name is quite mysterious (I do not have a better name)
• if copy_or_zeromem is handy in CCM then it should be perhaps also used in other encauth cases

[sjaeckel]

if copy_or_zeromem is handy in CCM then it should be perhaps also used in other encauth cases

I factored this out as I use it in my SIV PR as well, but I thought it doesn't really belong there, so I created this PR with other changes that belong to the features introduced there

I am not sure if we want it to be part of public API

I'll make it private for now

if it'll will be part of public API then the name is quite mysterious (I do not have a better name)

I think the name is okay'ish... probably one of the following would be better, not sure though:

1. mem_copy_or_zero
2. memcpy_or_zero
3. copy_or_zero
4. copy_or_clean

[karel-m]

If you make it private then no need to care about the name.

[sjaeckel]

If you make it private then no need to care about the name.

well I prefer to have a proper name now so we don't have to think about it in case we want to make it public ;)

Edit: I think the current name is fine and represents what the function does. Therefore we could even make it public.

[karel-m]

IIUC we are doing: "copy src to dest or zero dest (all that in constant time)" which sounds to me more like copy_or_zero_dest but I can live with copy_or_zeromem as well - I leave it up to you.

Another thing (UPDATED):

- coz &= 0x1;
+ if (coz != 0) coz = 1;

so that unexpected/accidental coz = 2 means zeromem (accidentally zeroing is better that copying)

[karel-m]

👍