Re: [Libguestfs] [PATCH 5/7] New APIs: add-domain and add-libvirt-dom.

On Wed, Nov 10, 2010 at 01:23:50PM +0000, Richard W.M. Jones wrote: > On Wed, Nov 10, 2010 at 01:17:54PM +0000, Daniel P. Berrange wrote: > > On Wed, Nov 10, 2010 at 11:46:31AM +0000, Richard W.M. Jones wrote: > > > +# This comes from the Sys::Virt bindings. > > > +INPUT > > > +O_OBJECT_domain > > > + if (sv_isobject ($arg) && (SvTYPE (SvRV ($arg)) == SVt_PVMG)) > > > + $var = ($type)SvIV ((SV*) SvRV ($arg)); > > > + else { > > > + warn(\"${Package}::$func_name() -- $var is not a blessed SV reference\"); > > > + XSRETURN_UNDEF; > > > + } > > > > I haven't been considering this Sys::Virt type mapping to be > > part of the stable ABI/API, just an internal impl details. I'm > > wondering how other Perl XS modules allow extension, without > > exposing their internal typedef implementation detail. > > Yup, this is a general problem with providing integration for these > pointers through any non-C language bindings. It could be alleviated > by having Sys::Virt provide a little bit of C to perform the SV -> > pointer conversion -- I think if it was in Sys/Virt/Virt.so then we > would be able to link to it. > > > > + /* Connect to libvirt, find the domain. */ > > > + conn = virConnectOpenReadOnly (libvirturi); > > > + if (!conn) { > > > + err = virGetLastError (); > > > + error (g, _("could not connect to libvirt (code %d, domain %d): %s"), > > > + err->code, err->domain, err->message); > > > + goto cleanup; > > > + } > > > + > > > + dom = virDomainLookupByName (conn, domain_name); > > > + if (!dom) { > > > + err = virConnGetLastError (conn); > > > > NB, virConnGetLastError() is deprecated because it isn't threadsafe. > > Instead use virGetLastError() in all places. > > Can I call this if I don't have a connection pointer? See first case > above.