Re: GDB/XMI (XML Machine Interface)

Bob Rossi
2004-08-21T12:34:52Z

On Sat, Aug 21, 2004 at 01:20:33PM +0300, Eli Zaretskii wrote:
> > Date: Fri, 20 Aug 2004 15:59:28 -0400
> > From: Bob Rossi <bob@brasko.net>
> >
> > Changing the MI output to XML would greatly reduce the amount of time
> > and code written to interface with GDB. Period. I strongly believe there
> > is no argument against this point.
>
> Strangely enough, none of the maintainers of the GDB front ends were
> enthusiastic about your proposal. Perhaps that's because they already
> have their MI parser written, so the issue of reducing the effort of
> writing one does not bother them.

Right, this is understandably so. I would also not be interested if I
had already written my mi1 and mi2 parser. However, that doesn't mean
it's not the correct decision. Instead of writing a new parser, they
will get one for free, that they will never have to maintain. Doesn't
that sound nice?

> > BTW, how does one go about getting a yes/no answer to such an RFC? Do I
> > need the approval of the majority of GDB contributors? maintainers?
>
> If you are looking for approval before you write the code, you've just
> heard the relevant opinions. I believe this is all you can hope for.
> Whether that is enough for you to sit down and start writing is
> something you should decide on your own.
>
> The way to get something into GDB is to write code and then submit it
> for approval. Then there are designated individuals (mentioned in
> MAINTAINERS) who should review the code and either approve it or point
> out the parts that should be rewritten or corrected.

These designated individuals either are busy or refuse to even discuss
the topic at hand. This is awfully unfriendly.

> > Also, why haven't some of the maintainers of MI responded at all on this
> > subject? Andrew or Elena? Fernando are you the main contact as far as
> > decisions on the MI code goes?
>
> I'm neither Andrew nor Elena nor Fernando, but I will try to summarize
> the impression I got from this discussion so far: your proposal
> mentioned several problems with MI, but most of those problems can
> (and IMHO should) be solved without ditching MI, and the effort to
> solve those problems with XMI is not going to be smaller. One notable
> example of such problems is back compatibility, but there were others.

I believe that making GDB output XML would be trivial.

> I agree that it would be a Good Thing if GDB would come with a
> read-to-use MI parser library. If you care about easing the pains of
> a GDB front-end programmer, then the project of writing such a parsing
> library should sound important to you. But since you said quite
> explicitly that you are not interested in such a project,

I am going to have to write an MI parser, if GDB refuses to simplfy it's
output. I have already been working on a project TGDB, and anyone that
wants to use it to base there front ends on GDB is welcome.

> I suspect
> that your interest is in playing with XML rather than easing the lives
> of front-end programmers out there. There's nothing wrong with your
> interest in XML, of course, but you must understand that the interests
> of GDB maintainers are elsewhere, and rightly so.

I care nothing about XML. As I say it over and over again. If XML is
outputted by GDB, it could be binary for all I care, NO parser has to be
written. The job has already been done.

I would not have to write a parser.
I would not have to write a library.
No one would.
Ever.

This is my point. I think that might have been my very first epilogue :)

BTW, if none of the front end writers or maintainers like this idea, I
will silently drop the issue. Personally, I thought many of the front
end writers would appreciate such a transparent protocol.

Thanks,
Bob Rossi