Eric Blake <ebl...@redhat.com> writes:
> On 07/24/2015 06:01 AM, Markus Armbruster wrote:
>
>>> It might be worth tweaking the generator to output a C comment either
>>> here (at the start of the larger struct)...
>>>
>>>> char *string;
>>>> EnumOne enum1;
>>>
>>> ...or here (at the end of the base struct) mentioning that
>>> UserDefFlatUnion can be cast into its base struct UserDefUnionBase, to
>>> make it easier when reading the generated code to trace back to that
>>> "inheritance" relationship. Right now, there is nothing in the
>>> generated UserDefFlatUnion that points you back to the qapi relationship
>>> of a base class. But it's not a show-stopper if you don't like my
>>> suggestion.
>>
>> I do like it. Perhaps something like
>>
>> struct UserDefFlatUnion
>> {
>> /* Members inherited from UserDefUnionBase: */
>> char *string;
>> EnumOne enum1;
>> /* Own members: */
>> ...
>> };
>
> What about nested types? Whatever we pick has to look good when
> indirect bases are involved. Suppose we have Base -> Mid -> Derived as a
> struct inheritance. If we generate a comment at both start and end of
> visiting a base class (and visit base classes recursively), we'd have
> something like:
>
> struct Derived
> {
> /* Members inherited from Mid */
> /* Members inherited from Base */
> int one;
> /* End members inherited from Base */
> int two;
> /* End members inherited from Mid */
> /* own members */
> int three;
> ...
> };
Documenting the direct ancestor in the code is more important than the
others, because you can always peruse the direct ancestor to find the
next one.
> Don't know if that helps you think about it more, but now I'm just
> painting a bikeshed that just adds the tail comment. Here's the
> resulting RFC:
>
> http://thread.gmane.org/gmane.comp.emulators.qemu/353204
>
> and the resulting generated structs:
>
> struct BlockdevOptionsQcow2 {
> - BlockdevOptionsGenericCOWFormat *base;
> + BlockdevRef *file;
> + /* End fields inherited from BlockdevOptionsGenericFormat. */
> + bool has_backing;
> + BlockdevRef *backing;
> + /* End fields inherited from BlockdevOptionsGenericCOWFormat. */
> bool has_lazy_refcounts;
> bool lazy_refcounts;
> ...
This and other followup patches are encouraging. I'll gladly review
them when I can spare the cycles. Right now, I need to focus them on
introspection.
