svn commit: r312296 - in head: lib/libc/sys sys/kern sys/netinet sys/netinet6 sys/sys tools/regression/sockets/udp_pingpong tools/regression/sockets/unix_cmsg

[Ian Lepore]

In my experience, enums are a superior way to define integer constants
(compared to #define), but they are pure poison as variable types in
APIs and structures because their size is a compiler implementation
choice.

-- Ian

On Tue, 2017-01-17 at 08:40 -0800, Maxim Sobolev wrote:
> That being said, is there any other socket option value in there
> implemented as enum? I don't see anything obvious, so that I am
> curious if
> it would stick out as an odd one in there. What do you think?
> 
> -Max
> 
> On Tue, Jan 17, 2017 at 6:22 AM, Maxim Sobolev <sobomax at freebsd.org>
> wrote:
> 
> > 
> > Of course it's possible. Do you guys want me to amend that patch?
> > 
> > -Max
> > 
> > On Mon, Jan 16, 2017 at 10:52 PM, Gleb Smirnoff <glebius at freebsd.or
> > g>
> > wrote:
> > 
> > > 
> > >   Hi!
> > > 
> > > On Mon, Jan 16, 2017 at 05:46:38PM +0000, Maxim Sobolev wrote:
> > > M> Author: sobomax
> > > M> Date: Mon Jan 16 17:46:38 2017
> > > M> New Revision: 312296
> > > M> URL: https://svnweb.freebsd.org/changeset/base/312296
> > > M>
> > > M> Log:
> > > M>   Add a new socket option SO_TS_CLOCK to pick from several
> > > different
> > > clock
> > > M>   sources to return timestamps when SO_TIMESTAMP is enabled.
> > > Two
> > > additional
> > > M>   clock sources are:
> > > M>
> > > M>   o nanosecond resolution realtime clock (equivalent of
> > > CLOCK_REALTIME);
> > > M>   o nanosecond resolution monotonic clock (equivalent of
> > > CLOCK_MONOTONIC).
> > > M>
> > > M>   In addition to this, this option provides unified interface
> > > to get
> > > bintime
> > > M>   (equivalent of using SO_BINTIME), except it also supported
> > > with IPv6
> > > where
> > > M>   SO_BINTIME has never been supported. The long term plan is
> > > to
> > > depreciate
> > > M>   SO_BINTIME and move everything to using SO_TS_CLOCK.
> > > M>
> > > M>   Idea for this enhancement has been briefly discussed on the
> > > Net
> > > session
> > > M>   during dev summit in Ottawa last June and the general input
> > > was
> > > positive.
> > > M>
> > > M>   This change is believed to benefit network
> > > benchmarks/profiling as
> > > well
> > > M>   as other scenarios where precise time of arrival measurement
> > > is
> > > necessary.
> > > M>
> > > M>   There are two regression test cases as part of this commit:
> > > one
> > > extends unix
> > > M>   domain test code (unix_cmsg) to test new SCM_XXX types and
> > > another
> > > one
> > > M>   implementis totally new test case which exchanges UDP
> > > packets
> > > between two
> > > M>   processes using both conventional methods (i.e. calling
> > > clock_gettime(2)
> > > M>   before recv(2) and after send(2)), as well as using
> > > setsockopt()+recv() in
> > > M>   receive path. The resulting delays are checked for sanity
> > > for all
> > > supported
> > > M>   clock types.
> > > M>
> > > M>   Reviewed by:    adrian, gnn
> > > M>   Differential Revision:  https://reviews.freebsd.org/D9171
> > > 
> > > Is it possible to declare possible values as a enum and make
> > > so_ts_clock
> > > fields of that enum type?
> > > 
> > > --
> > > Totus tuus, Glebius.
> > > 
> > >