On Sun, Feb 28, 2021 at 1:40 PM Samuel Thibault <samuel.thibault@gnu.org>
wrote:

> [...]
> > Note that one issue I am leaving for later (i.e., I don't want to drag
> this
> > patch series out to include it), is whether and how to support
> ipv4-host->
> > ipv6-guest forwarding and vice versa. Can libslirp support this?
>
> That would be feasible yes: since the data flow is completely rebuilt
> between the host and the guest, there is no remnant of the IP version.
> It was simpler to have e.g. udp_listen and udp6_listen separate to keep
> uint32_t / in6_addr parameters, but there is no strict reason for this:
> the haddr is only passed to the bind() call, and the laddr is only
> recorded in the so. Put another way, a refactoring patch could be to
> just hand udp_listen two sockaddrs, and it will just work fine. We'd
> then introduce a slirp_add_hostfwd that takes two sockaddr instead of
> host/port.
>


I guess I'm not familiar enough with this code.
Help me understand how passing two addresses to udp_listen is simpler.
That feels confusing from an API viewpoint.