[gdal-dev] json-c 0.10 update status and json-c copy removal proposed

[Even Rouault]

> I have no idea what could be submitted and what couldn't.
> So, if you care, submit a pull request
> https://github.com/json-c/json-c
> or just forward these functions to
> https://groups.google.com/forum/#!forum/json-c

I'll try to, but not before end of week.

> I have patched json-c for Windows and Visual C++, and patches have
> been accepted,
> so I guess there is no problem with building for Windows/OSGeo4W.

Do we need json-c 0.10 to be able to build it for Windows ? Or was 0.9 already
OK ?

>
> >> I don't see any reason why GDAL couldn't rely on external json-c.
> >> So, I'd like to propose to:
> >> - remove GDAL's copy of json-c from ogr/ogrsf_frmts/geojson/jsonc
> >> - configure Unix and Windows builds to use external binaries
> >
> > I assume you will deal with the libjsonc dependency as an optional one ?
>
> If GDAL agrees to use external libjsonc, then I will make it optional
> in build config.
> If that's what you mean.

Yes

> > For the ease of using on Linux, it would be good if libjson-c 0.9 could
> still be
> > used, being the version currently packaged.
>
> I have no idea to what extent the API has changed in 0.10, but I can
> give it a try.

Hopefully the API (at least, the subset used by the GDAL/OGR drivers) hasn't
changed. If it has, I think we will have to adapt to the 0.9 and 0.10 API.

> To summary, I plan the following steps during next week or so:
>
> 0. Work will happen in trunk only
> 1. I will remove the json-c sources
> 2. I will configure build to use external libjsonc (preferably 0.9+)
> 3. I will update the drivers, if necessary.
> 4. I will update the tests, if necessary.
> 5. Once confirmed sound on Linux, I will push changes as single commit.
> 6. I continue testing on Windows (hopefully someone will be willing to
> help with testing for Windows).
>
> Do you agree?
>
> I think I'll make a ticket for reference too.

Sounds good to me. If we need libjson-c 0.10 for having something that builds
under Windows, then I think it will be best to wait for it to be officially
released before removing the internal copy from GDAL trunk.

Best regards,

Even