additional functions mp_incr and mp_decr

[czurnieden]

First batch.
The functions are interdependent, they call each other in case of negative input.

[minad]

Looks good except for the whitespace changes.

[czurnieden]

Looks good except for the whitespace changes.

But @sjaeckel was very nice and helped me to install a hook to…oh, that was only for that branch not for all. My bad, sorry.

I'm currently building the PR for mp_ilogb which won't need long (hopefully ;-) ) and clean up when that is done.

EDIT: @minad took a look at it. Run make astyle and got nothing about my functions but a bunch of files got formatted, files I didn't touch. Check in branch develop: up-to-date and the same reaction to astyle. What happened? Oh, and while we are at it: tried to use IS_ZEROin test.c but it includes tommath.h only, IS_ZERO is in tommath_private.h. What is the reason for that restriction?

[sjaeckel]

which whitespace changes?

[sjaeckel]

What is the reason for that restriction?

Tests should only use the public API. For your case there's still mp_iszero()... but I can also live with mp_cmd_d()

[sjaeckel]

which whitespace changes?

@minad *ping*

[minad]

@sjaeckel I was on mobile and I think I confused the two PRs by @czurnieden. See here https://github.com/libtom/libtommath/pull/191/files#diff-aa67c18ca27d74fae0446b5cd9376391L14.