custom printing messages with your assertion trips

[rincebrain]

Motivation and Context

I kept rewriting assertions into if(assert condition) { print something; trip assertion; } and went "this probably works".

So now I want to see if the CI explodes on Debian 8 or something.

(Before merge I'd probably refactor the non-f versions into being in terms of the f versions, but this way I can test a much smaller blast radius at a time...also suggestions for better naming welcome.)

(...I also flattened freebsd's debug.h and linux's after noticing they were more or less the same file, but that's mostly orthogonal and just in here because I also want to make sure that compiles everywhere.)

Description

Gives all the ASSERT/VERIFY macros an "f" suffix variant that adds "STR, ..." arguments such that you could do, say
ASSERT3Pf(hdr->b_l1hdr.b_pabd, !=, NULL, "hdr %px buf %px", hdr, buf);
and get an error trip like
VERIFY3(hdr->b_l1hdr.b_pabd != NULL) failed (0000000000000000 != 0000000000000000) hdr 0000000000000000 buf 0000000000000000

The only big caveat is I don't think you can do something like ((void) __VA_ARGS__) so the print varargs won't always get executed, so don't put side effect things in there you need to always run...but that's not a reason not to have it, just a warning.

How Has This Been Tested?

I mean, I compiled it once, what could go wrong, right?

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Performance enhancement (non-breaking change which improves efficiency)
• Code cleanup (non-breaking change which makes code smaller or more readable)
• Breaking change (fix or feature that would cause existing functionality to change)
• Library ABI change (libzfs, libzfs_core, libnvpair, libuutil and libzfsbootenv)
• Documentation (a change to man pages or other documentation)

Checklist:

• My code follows the OpenZFS code style requirements.
• I have updated the documentation accordingly.
• I have read the contributing document.
• I have added tests to cover my changes.
• I have run the ZFS Test Suite with this change applied.
• All commit messages are properly formatted and contain Signed-off-by.

[rincebrain]

Amazing. I...can't reopen this.

[rincebrain]

Or maybe it just wanted a less stale force push? I don't really know.