Re: [B.A.T.M.A.N.] [PATCH-marek] batman-adv: Unify the first 3 bytes in each packet

Marek Lindner
2011-05-28T12:17:14Z

On Saturday 28 May 2011 14:07:10 Sven Eckelmann wrote:
> Why dont you use the reserverd part for the flags which are currently not
> in unicast? Then you could also remove that other align byte. It would
> still be possible to add flags to unicast packets when necessary.

The unicast_frag header assumes it looks like the unicast header plus some
extra fields:

struct unicast_frag_packet {
struct unicast_packet unicast_packet;
uint8_t flags;
uint8_t align;
uint8_t orig[6];
uint16_t seqno;
};

We probably should add a little comment there to make that clear.

Both reserved fields (unicast + unicast frag) are going to be converted to
ttvn with the tt patches.

> > + uint8_t reserved;
> > + uint8_t orig[6];
> >
> > uint32_t seqno;
> >
> > } __packed;
>
> Wouldn't that lead to an unaligned seqno?

Yes, I overlooked that the seqno is 32bit wide.

Regards,
Marek