Subject: Re: [RFC net-next 0/4] ynl: YAML netlink protocol descriptions

From: Jakub Kicinski <[email-masked]>
Date: Thu, 11 Aug 2022 08:34:35 -0700

Randomly adding Michal to CC since I just realized I forgot
to CC him on the series.

On Thu, 11 Aug 2022 08:01:52 -0700 Stephen Hemminger wrote:
> > On Wed, 10 Aug 2022 21:15:34 -0700 Stephen Hemminger wrote:  
> > > Would rather this be part of iproute2 rather than requiring it
> > > to be maintained separately and part of the kernel tree.    
> > 
> > I don't understand what you're trying to say. What is "this", 
> > what is "separate" from what?  
> 
> I am saying that ynl could live as a standalone project or as
> part of the iproute2 tools collection.

It's a bit of a strange beast, because the YNL C library ends up being
relatively small:

 tools/net/ynl/lib/ynl.c                  | 528 +++++++++++++++++++++++++
 tools/net/ynl/lib/ynl.h                  | 112 ++++++

The logic is mostly in the codegen:

 gen.py                                   | 1601 +++++++++++++++++++++++++

but that part we need for kernel C code as well.

The generated code is largish:

 tools/net/ynl/generated/dpll-user.c      | 371 ++++++++++++++++++
 tools/net/ynl/generated/dpll-user.h      | 204 ++++++++++
 tools/net/ynl/generated/ethtool-user.c   | 367 ++++++++++++++++++
 tools/net/ynl/generated/ethtool-user.h   | 190 +++++++++
 tools/net/ynl/generated/fou-user.c       | 322 ++++++++++++++++
 tools/net/ynl/generated/fou-user.h       | 287 ++++++++++++++
 tools/net/ynl/generated/genetlink-user.c | 635 +++++++++++++++++++++++++++++++
 tools/net/ynl/generated/genetlink-user.h | 201 ++++++++++

but we don't have to commit it, it can be created on the fly 
(for instance when a selftest wants to make use of YNL).

Then again it would feel a lot cleaner for the user space library
to be a separate project. I've been putting off thinking about the
distribution until I'm done coding, TBH. Dunno.