[libvirt] [PATCH v2] Fix cast errors with clang

[Roman Bogorodskiy]

  Eric Blake wrote:

> On 10/21/2014 08:22 AM, Roman Bogorodskiy wrote:
> > Build with clang fails with:
> > 
> >   CC       util/libvirt_util_la-virsocketaddr.lo
> > util/virsocketaddr.c:904:17: error: cast from 'struct sockaddr *' to
> > 'struct sockaddr_in *' increases required alignment from 1 to 4
> > [-Werror,-Wcast-align]
> >         inet4 = (struct sockaddr_in*) res->ai_addr;
> >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > util/virsocketaddr.c:909:17: error: cast from 'struct sockaddr *' to
> > 'struct sockaddr_in6 *' increases required alignment from 1 to 4
> > [-Werror,-Wcast-align]
> >         inet6 = (struct sockaddr_in6*) res->ai_addr;
> >                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > 2 errors generated.
> > 
> > Fix that by replacing virSocketAddrParseInternal() call with
> > virSocketAddrParse() in the virSocketAddrIsNumericLocalhost() function.
> > virSocketAddrParse stores an address in virSocketAddr.
> > virSocketAddr uses a union to store an address, so it doesn't
> > need casting.
> > ---
> >  src/util/virsocketaddr.c | 20 ++++++--------------
> >  1 file changed, 6 insertions(+), 14 deletions(-)
> > 
> 
> >      bool ret = false;
> 
> You could drop this...
> 
> >  
> > -    if (virSocketAddrParseInternal(&res, addr, AF_UNSPEC, false) < 0)
> > +    if (virSocketAddrParse(&res, addr, AF_UNSPEC) < 0)
> >          return ret;
> 
> by making this 'return false'
> 
> >  
> > -    switch (res->ai_addr->sa_family) {
> > +    switch (res.data.stor.ss_family) {
> >      case AF_INET:
> > -        inet4 = (struct sockaddr_in*) res->ai_addr;
> > -        ret = memcmp(&inet4->sin_addr.s_addr, &tmp.s_addr,
> > -                     sizeof(inet4->sin_addr.s_addr)) == 0;
> > -        break;
> > +        return memcmp(&res.data.inet4.sin_addr.s_addr, &tmp.s_addr,
> > +                     sizeof(res.data.inet4.sin_addr.s_addr)) == 0;
> >      case AF_INET6:
> > -        inet6 = (struct sockaddr_in6*) res->ai_addr;
> > -        ret = IN6_IS_ADDR_LOOPBACK(&(inet6->sin6_addr));
> > -        break;
> > +        return IN6_IS_ADDR_LOOPBACK(&res.data.inet6.sin6_addr);
> >      }
> >  
> > -    freeaddrinfo(res);
> >      return ret;
> 
> and also this one. (ret is never assigned anything else in the
> function).  Whether or not you make that additional cleanup,
> 
> ACK.

Thanks; pushed with the 'ret' dropped.

Roman Bogorodskiy