[libvirt] [PATCH] 2/3 Store the range size when adding a DHCP range

[Daniel P. Berrange]

On Wed, Oct 14, 2009 at 02:31:29PM +0200, Daniel Veillard wrote:
> On Wed, Oct 14, 2009 at 12:33:36PM +0100, Daniel P. Berrange wrote:
> > > > 
> > > > It would be nice to have this in a callable function too
> > > > 
> > > >      int virSocketAddrRange(struct sockaddr_storage *start,
> > > >                             struct sockaddr_storage *end);
> > > 
> > >   Are you supposed to look struct sockaddr_storage ? As posted in my
> > > last mail this seems a completely opaque structure at least in theory
> > > and if you want to keep the portability it's supposed to bring.
> > 
> > You cast to one of the address specific structs according
> > to the ss_family field.
> 
>   humpf ... okay it has to be cast to be accessed, that's weird,
> definitely.

Yeah, ideally it would have been in a union, but POSIX the way it was
defined when sockets API were first designed, didn't allow a union to
be retrofitted. 

We could consider a union ourselves though for our API if it might 
make it a little clearer, eg

   typedef union {
      struct sockaddr_storage stor;
      struct sockaddr_in inet4;
      struct sockaddr_in6 inet6;
   } virSocketAddr;

to allow more direct access without the casting

Daniel
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