Hello,
Thomas Huth, on Fri 19 Feb 2016 14:44:59 +0100, wrote:
> > + m->m_data -= sizeof(struct tcpiphdr) - (sizeof(struct ip)
> > + + sizeof(struct tcphdr));
> > + m->m_len += sizeof(struct tcpiphdr) - (sizeof(struct ip)
> > + + sizeof(struct tcphdr));
>
> I'm somewhat having a hard time to understand the "+ sizeof(struct
> tcphdr))" here.
>
> In the tcp_output.c code, there is this:
>
> m->m_data += sizeof(struct tcpiphdr) - sizeof(struct tcphdr)
> - sizeof(struct ip);
>
> So with my limited point of view, I'd rather expect this here in
> tcp_input.c:
>
> m->m_data -= sizeof(struct tcpiphdr) - (sizeof(struct ip)
> - sizeof(struct tcphdr));
> i.e. "-" instead of "+" here ----------------^
The parentheses and indentation were misleading actually, here is how it
should actually looks like:
> > + m->m_data -= sizeof(struct tcpiphdr) - ( sizeof(struct ip)
> > + + sizeof(struct tcphdr));
I've now dropped the parentheses, so it looks like the tcp_output.c code:
m->m_data -= sizeof(struct tcpiphdr) - sizeof(struct ip)
- sizeof(struct tcphdr);
Samuel
