Re: [Libguestfs] [PATCH 3/3] Add APIs for resolving the appliance kernel/initrd
On Tue, Jul 06, 2010 at 12:15:12PM +0100, Daniel P. Berrange wrote:
On Tue, Jul 06, 2010 at 08:30:21AM +0100, Richard W.M. Jones wrote:
> On Mon, Jul 05, 2010 at 12:26:01PM -0400, Daniel P. Berrange wrote:
>
> > + ("get_kernel", (RConstString "kernel", []), -1, [],
>
> RConstString is the wrong type to use here, I think.
>
> If users should call find_appliance before this, then it should be an
> error not to have called it, so RString would be the correct return
> type.
Using RString introduces a needless strdup & free between
libguestfs & the caller, so I chose RConstString to avoid
this. Both RString and RConstString declare that NULL is
an error condition, so I'm not sure why we need to change
this to RString since they're appear to be equivalent in
their error reporting semantics.
OK I think you're right. It's RConstOptString which is the one which
should [nearly] never be used.
But you should still alter the code so that it calls error() if the
internal g->kernel (or g->initrd) field is NULL.
Rich.
--
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