Re: [PATCH v4 2/3] module: add Error arguments to module_load_one and module_load_qom_one

["Daniel P. Berrangé" <berrange@redhat.com>]

On Thu, Sep 22, 2022 at 11:20:07AM +0200, Claudio Fontana wrote:
> On 9/22/22 10:28, Daniel P. Berrangé wrote:
> > 
> >> Another interface that does: return -1 for error, 0 for module not found
> >> (no error), and 1 for loaded.
> > 
> > IMHO this pattern is generally easier to understand when looking at
> > the callers, as the fatal error scenario is always clear.
> > 
> > That said I would suggest neither approach as the public facing
> > API. Rather stop trying to overload 3 states onto an error reporting
> > pattern that inherantly wants to be 2 states. Instead just have
> > distinct methods
> > 
> >   bool module_load_one(const char *prefix, const char *name, Error *errp)
> >   bool module_try_load_one(const char *prefix, const char *name, Error *errp)
> 
> 
> Here we are murking again the normal behavior and the error path.
> 
> What is the meaning of try? It's not as though we would error out inside the function module_load_one,
> it's the _caller_ that needs to decide how to treat a return value of found/not found, and the exception (Error).

I suggested "try" as in the  g_malloc vs g_try_malloc API naming pattern,
where the latter ignores the OOM error condition.

So in this case 'try' means try to load the module, but don't fail if
the module is missing on disk.

With regards,
Daniel
-- 
|: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org         -o-            https://fstop138.berrange.com :|
|: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|