From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira Ayuso <pablo@netfilter.org>
Subject: Re: [PATCH libmnl] nlmsg: introduce mnl_nlmsg_batch_rest to get the
 rest length
Date: Fri, 14 Apr 2017 00:27:00 +0200
Message-ID: <20170413222700.GA5024@salvia>
References: <20170403061127.GA2329@gmail.com>
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To: Ken-ichirou MATSUZAWA <chamaken@gmail.com>
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On Mon, Apr 03, 2017 at 03:11:27PM +0900, Ken-ichirou MATSUZAWA wrote:
> Recent languages implements array to hold its length. This patch
> enables to help to wrap these. As of this C library, we can use
> this like below without double sized buffer.
> 
>     char buf[MNL_SOCKET_BUFFER_SIZE];
> 
>     b = mnl_nlmsg_batch_start(buf, sizeof(buf));
>     nlbuf = mnl_nlmsg_batch_current(b);
>     rest = mnl_nlmsg_batch_rest(b);
>     if (rest < NLMSG_HDRLEN)
>             return false;

Only for this usecase above?

>     nlh = mnl_nlmsg_put_header(nlbuf);

Probably we need mnl_nlmsg_put_header_check()?

>     ...
>     if (!mnl_attr_put_u8_check(nlh, rest, 1, 2))
>             return false;
>     ...