Re: wcstold implementation

[Craig Howland <howland at LGSInnovations dot com>]

On 01/22/2015 12:44 PM, Craig Howland wrote:
> On 01/22/2015 11:16 AM, Corinna Vinschen wrote:
> > On Jan 22 16:28, Corinna Vinschen wrote:
> >
> >
> > On Jan 22 15:11, Nick Clifton wrote:
> > > > Hi Corinna, Hi Yaakov,
> > > >
> > > >    What do you think of the attached patch for an implementation of
> > > >    wcstold() for sizeof (long double) > sizeof (double) ? The patch is
> > > >    against the devo sources, but it could be adapted for FSF newlib
> > > >    easily enough.  One thing that you might not like is that the
> > > >    _wcstold_r implementation calls _strtold and not _strtold_r.  I can
> > > >    fix this too if you think that it is worth it.
> > > We don't have a _strtold_r function, only _strtold.  Along these lines,
> > > I think it should be sufficent to implement wcstold and just skip
> > > _wcstold_r.
> > Hmm, on second thought.
> >
> > The _strtold function in ldtoa.c is old, it never sets errno, it doesn't
> > take _localeconv_r (ptr)->decimal_point into account...
> >
> > Maybe we should in fact start with creating an _strtold_r function from
> > the _strtod_r function first?
> I actually have a _strtold_r() function that I did back in 2009 but never 
> quite got to the last step of submitting.  I had gotten an updated version of 
> ldtoa.c (the present one in Newlib is not David Gay's latest), and made a 
> wrapper for it.
>
> One thing that I did is that the function call for _strtold_r() has an 
> additional argument over strtold() to allow it to be called from scanf.  The 
> former wants errno set but the latter does not.
>
> It does not, however, have the locale thing, as that was added after I had 
> done it.
>
> I have attached it for discussion and as a possible starting point. The exact 
> method by which error or not errno is handled is a question.  As noted, I had 
> put it into the _strtold_r() call, rather than having yet another wrapper 
> level.  The reasoning is that you already need to add the reentry pointer, so 
> another argument different from the standard call is not necessarily a bad thing.
>
> The list mailer bounced with all 3 files, so here are 2, the other will follow.
>
> Craig
Here is the "new" ldtoa.c for the discussion.

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