Re: Testers wanted: reentrant resolver

On Fri, 20 Feb 2004, Brian F. Feldman wrote:

> Daniel Eischen <eischen_at_vigrid.com> wrote:
> > > Other APIs have the option of failing.  __h_errno() does not have the option 
> > > of failing, so what do I do if pthread_key_create() fails?  Also, if 
> > > malloc() fails each time pthread_getspecific() returns NULL for the thread?
> > 
> > The API isn't thread-safe by design, so if malloc() fails,
> > just use the global errno.  A better design would be to
> > add the thread-safe interfaces I mention above, and have
> > the non-thread-safe interfaces first do the pthread_once(),
> > pthread_[gs]etspecific() thing and then call the thread-safe
> > interfaces.  Since the malloc() will be the first thing
> > in the entry point, you can fail right away:
> 
> Ok, just had a "good idea".  Since h_errno belongs to the resolver, too, why 
> don't I just implement __h_errno() inside res_init.c and make the storage 
> come from the same place the per-thread struct _res {} storage comes from?  
> That should make you happy, and it makes me happy because it doesn't add an 
> "extra" failure point.

That's exactly what I meant when I said:

> > Ugh, can you put h_errno inside the per-thread res stuff.

:-)

-- 
Dan Eischen