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From: Marek Lindner <lindner_marek@yahoo.de>
Date: Sat, 28 May 2011 14:17:14 +0200
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Subject: Re: [B.A.T.M.A.N.] [PATCH-marek] batman-adv: Unify the first 3
	bytes in each packet
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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