Re: [iptables PATCH] configure: make libmnl and libnftnl hard requirements

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Tue, Apr 26, 2016 at 11:20:19PM +0200, Jan Engelhardt wrote:
> 
> On Tuesday 2016-04-26 21:27, Giuseppe Longo wrote:
> >index 12bffa9..b170add 100644
> >--- a/configure.ac
> >+++ b/configure.ac
> >@@ -122,8 +122,26 @@ AM_CONDITIONAL([HAVE_LIBNFNETLINK], [test "$nfnetlink" = 1])
> > if test "x$enable_nftables" = "xyes"; then
> > 	PKG_CHECK_MODULES([libmnl], [libmnl >= 1.0], [mnl=1], [mnl=0])
> > 
> >+	if test "$mnl" = 0;
> >+	then
> >+		echo "*** Error: No suitable libmnl found. ***"
> >+		echo "    Please install the 'libmnl' package"
> >+		echo "    Or consider --disable-nftables to skip"
> >+		echo "    iptables-compat over nftables support."
> >+		exit 1
> >+	fi
> 
> As told you before, I find this unnecessary large.
> Consider this instead.
> 
> 
> From afcbd592265af0c3a65c21e8f23e1c2f5a348396 Mon Sep 17 00:00:00 2001
> From: Jan Engelhardt <jengelh@inai.de>
> Date: Tue, 26 Apr 2016 23:18:26 +0200
> Subject: [PATCH] build: hard-require libmnl, libnftnl for iptables-nft
> 
> Signed-off-by: Jan Engelhardt <jengelh@inai.de>
> ---
>  configure.ac | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/configure.ac b/configure.ac
> index 12bffa9..e4eafc6 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -120,9 +120,10 @@ PKG_CHECK_MODULES([libnfnetlink], [libnfnetlink >= 1.0],
>  AM_CONDITIONAL([HAVE_LIBNFNETLINK], [test "$nfnetlink" = 1])
>  
>  if test "x$enable_nftables" = "xyes"; then
> -	PKG_CHECK_MODULES([libmnl], [libmnl >= 1.0], [mnl=1], [mnl=0])
> -
> -	PKG_CHECK_MODULES([libnftnl], [libnftnl >= 1.0.5], [nftables=1], [nftables=0])
> +	PKG_CHECK_MODULES([libmnl], [libmnl >= 1.0])
> +	PKG_CHECK_MODULES([libnftnl], [libnftnl >= 1.0.5])
> +	mnl=1
> +	nftables=1

This doesn't give a clue to users on what they can actually do.

I find Giuseppe's patch more informative.