Re: [v3,1/4] tools: bpftool: add net attach command to attach XDP on interface

[Jakub Kicinski]

On Thu, 8 Aug 2019 07:15:22 +0900, Daniel T. Lee wrote:
> > > +             return -EINVAL;
> > > +     }
> > > +
> > > +     NEXT_ARG();  
> >
> > nit: the new line should be before NEXT_ARG(), IOV NEXT_ARG() belongs
> > to the code which consumed the argument
> >  
> 
> I'm not sure I'm following.
> Are you saying that, at here the newline shouldn't be necessary?

I mean this is better:

        if (!is_prefix(*argv, "bla-bla"))
                return -EINVAL;
        NEXT_ARG();

        if (!is_prefix(*argv, "bla-bla"))
                return -EINVAL;
        NEXT_ARG();

Than this:

        if (!is_prefix(*argv, "bla-bla"))
                return -EINVAL;

        NEXT_ARG();
        if (!is_prefix(*argv, "bla-bla"))
                return -EINVAL;

        NEXT_ARG();

Because the NEXT_ARG() "belongs" to the code that "consumed" the option.

So instead of this:

     attach_type = parse_attach_type(*argv);
     if (attach_type == max_net_attach_type) {
             p_err("invalid net attach/detach type");  
             return -EINVAL;
     }

     NEXT_ARG();  
     progfd = prog_parse_fd(&argc, &argv);
     if (progfd < 0)
             return -EINVAL;

This seems more logical to me:

     attach_type = parse_attach_type(*argv);
     if (attach_type == max_net_attach_type) {
             p_err("invalid net attach/detach type");  
             return -EINVAL;
     }
     NEXT_ARG();  

     progfd = prog_parse_fd(&argc, &argv);
     if (progfd < 0)
             return -EINVAL;