From: Jeff King <peff@peff.net>
Date: Thu, 01 Dec 2016 20:26:03 GMT
Subject: Re: [PATCH 1/3] compat: add qsort_s()
Message-ID: <20161201202602.sfs6ycmh32ib5ed7@sigill.intra.peff.net>
In-Reply-To: <xmqqy3zz8kmq.fsf@gitster.mtv.corp.google.com>

On Thu, Dec 01, 2016 at 12:22:37PM -0800, Junio C Hamano wrote:

> Junio C Hamano <gitster@pobox.com> writes:
> 
> > Eh, wait.  BSD and Microsoft have paramters reordered in the
> > callback comparison function.  I suspect that would not fly very
> > well.
> 
> Hmm.  We could do it like this, which may not be too bad.

Heh. Exactly, but I was too lazy to write it out in my other email. :)

The no-cost version would be more like:

#ifdef APPLE_QSORT_R
#define DECLARE_CMP(func) int func(void *data, const void *va, const void *vb)
#else
#define DECLARE_CMP(func) int func(const void *va, const void *vb, void *data)
#endif

and then:

  DECLARE_CMP(foocmp);
  ...

  DECLARE_CMP(foocmp)
  {
	const struct foo *a = va, *b = vb;
	... etc ...
  }

-Peff