Branko Čibej wrote on Wed, May 11, 2011 at 22:15:58 +0200:
> On 11.05.2011 22:11, Daniel Shahaf wrote:
> > Greg Stein wrote on Wed, May 11, 2011 at 15:35:19 -0400:
> >> On May 11, 2011 2:05 PM, "C. Michael Pilato" <cmpil...@collab.net> wrote:
> >>> On 05/11/2011 12:00 PM, Daniel Shahaf wrote:
> >>> ...
> >>>> When wrapping apr_status_t's returned by serf, shouldn't we decorate
> >>>> them in some way so that code that interprets them knows to look them up
> >>>> in serf.h:SERF_ERROR_* rather than in svn_error_codes.h ?
> >>>>
> >>>> Not sure, perhaps a wrapper err->apr_err link that signals to
> >>>> subr/error.c to call into serf to stringify the child link...?
> >>> I'm actually not sure that Serf even provides a stringification function
> >> at
> >>> all.
> >> Good idea. I can fix that.
> >>
> >>> svn_error_wrap_apr() will use 'status' as the err->apr_err value, but
> >>> will call APR's stringification function which, I would expect, would just
> >>> drop some generic string in place (since the Serf error code range is
> >>> outside of APR's own). Of course, there's no guarantee that Subversion's
> >>> and Serf's error code ranges won't overlap,
> >> You have a guarantee :-)
> > Since svn_error_t.apr_err may contain either an svn error code or a serf
> > error code, do we care to have an API that tells people which one it is?
> >
> > Use case: API consumers who don't log err->message and want to
> > call svn_strerror(err->apr_err).
>
> It would be much better if the interface code converted Serf error codes
> to an interval that does not conflict with either APR or Subverison
> codes. Otherwise you'll never see the end of hacking special-case error
> normalization APIs every time we happen to start using another library
> that works on top of APR.
>
We don't add dependencies very often.
That said, if Greg can guarantee that Serf will never use more than 5000
error codes, we could use
svn_error_t *
svn_error_wrap_serf(apr_status_t serf_err, ...)
{
return svn_error_wrap_apr(serf_err + SVN_ERROR_SERF_CATEGORY_START, ...);
}
> (It doesn't help that APR does a poor job of aiding code-space
> reservation, but crying over spilt milk won't solve the problem at hand.)
>
> -- Brane
