patch: portable dirhash

[Robert Watson]

On Wed, 17 Dec 2003, Alexander Kabaev wrote:

> On Tue, 16 Dec 2003 22:12:08 -0500 (EST)
> Ted Unangst <tedu at zeitbombe.org> wrote:
> 
> > can somebody please review/commit this to freebsd?  it is most of the 
> > differences to permit openbsd to use the code.  it should not change
> > the code in any functional way.
> 
> I do not think there is any point in this code ever hitting FreeBSD CVS
> repository. Rather, OpenBSD should just take cleaned-out copy of this
> code and be done with it. 

Well, it's true the #ifdef OpenBSD's probably don't help the readability
of our code, abstracting a step by using macros to wrap specific locking
primitives is a widely used approach in the FreeBSD tree, especially where
it's not clear a final locking strategy has been developed due to a lack
of profiling.  For example, in both the network code and process
management code, we wrap mutexes/sxlocks in macros to avoid committing to
either, and to make changing the strategy easier.  I wouldn't object to
our adopting the macro wrapping, which would have the side effect of
helping the OpenBSD patch size a lot also, even leaving out the #ifdef's.

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Senior Research Scientist, McAfee Research