[Libguestfs] [PATCH nbdkit 1/2] file: Add an internal "mode"

[Eric Blake]

On Thu, Aug 18, 2022 at 10:27:11AM +0200, Laszlo Ersek wrote:
> > @@ -180,14 +181,23 @@ file_config (const char *key, const char *value)
> >     * existence checks to the last possible moment.
> >     */
> >    if (strcmp (key, "file") == 0) {
> > -    free (filename);
> > +    if (mode != mode_none) {
> > +    wrong_mode:
> 
> *shudder*
> 
> please move error handling sections to the end of the function. It's OK
> to jump forward in exceptional cases, but crossing jump lines (i.e.
> improper balancing / nesting) and backward jumps for error handling are
> terrible.
> 
> Just my opinion :)

I've used the same style in recent patches to libnbd (because it was
pre-existing), but I can also agree to favor a forward jump to a
common error handling at the bottom of the function rather than a
backward jump to a mid-if label.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org