RE: [lwip-devel] byte order, packing, optimizations

[Stéphane Lesage]

> > Here is another patch to remove struct packing for dns_query and
> > dns_answer in dns.c, which is not needed since we memcpy them.
> >    
> Don't beat me, but I fixed it the other way round: don't
> memcpy and use pointers instead. Still, thanks for pointing this out.

Yeah that's more elegant when having 1 byte packing...
The problem is that people who optimize will use 2 bytes or no packing, 
and it won't work for them.

I was preparing another patch for
- combine load/stores and ntohX/htonX (lwip packing)
- other macros for reading/writing unaligned words for such protocols

> > - change ip_addr_is_broadcast to a more efficient macro
> >   
> That change actually changes the behaviour of ip_addr_is_broadcast().
> Was that intended? I don't think the change is correct, or is it?

I removed:
- the broadcast with 0.0.0.0 "old style comment", is it really used ?
- comparison to netif address, useful only when mask=255.255.255.255 -> 
the netif should not support broadcast

I optimize the comparison to broadcast address = network address OR (NOT 
mask)