Re: [Draft iproute2-next PATCH] configure: add options ability

[David Ahern <dsahern@gmail.com>]

On 5/28/21 6:35 AM, Hangbin Liu wrote:
> From: Hangbin Liu <haliu@redhat.com>
> 
> Hi David,
> 
> As we talked in my previous libbpf support patchset. You'd like to make
> configure with option settings. Here is a draft patch. Not sure if this
> is what you want.
> 
> There are also a lot variables that I not sure if we should add options
> for them. e.g. PKG_CONFIG, CC, IPTC, IPT_LIB_DIR, etc. Do you have any
> suggestions?

I think it is better to have command line options vs environment
variables. Command line options can be used with a usage / help function
to make it easier for users to learn or remember the config options.

That said, the environment variable approach should continue to work for
existing build scripts.

Your RFC looks fine to me. It would be easier to review if options are
converted with separate patches vs one big one.



> +while true; do
> +	case "$1" in
> +		--libbpf_force)
> +			if [ "$2" != 'on' ] && [ "$2" != 'off' ]; then
> +				usage 1
> +			fi
> +			LIBBPF_FORCE=$2
> +			shift 2 ;;
> +                --libbpf_dir)
> +			LIBBPF_DIR="$2"
> +                        shift 2 ;;
> +                --include_dir)
> +			# How to deal with the old INCLUDE usage?

if number of input arguments is just 1 and it does not start with '-',
then guess that it is old style INCLUDE.

Thanks for working on this.