Re: [PATCH] parser: Fix VSLENGTH parsing with trailing garbage

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

On Mon, Jun 21, 2021 at 04:21:40PM +0200, Denys Vlasenko wrote:
>
> > diff --git a/src/parser.c b/src/parser.c
> > index 3c80d17..13c2df5 100644
> > --- a/src/parser.c
> > +++ b/src/parser.c
> > @@ -1252,7 +1252,8 @@ varname:
> >                         do {
> >                                 STPUTC(c, out);
> >                                 c = pgetc_eatbnl();
> > -                       } while (!subtype && is_digit(c));
> > +                       } while ((subtype <= 0 || subtype >= VSLENGTH) &&
> > +                                is_digit(c));
> 
> ... you use (subtype == 0 || subtype == VSLENGTH) here.
> Also, (subtype == 0 || subtype == VSLENGTH) is less confusing:
> it says "loop if ${VAR} or ${#VAR} syntax", whereas <= >=
> are a bit misleading.

Yes it looks a bit confusing, but it turns into a single branch
instead of two.  Perhaps I should add a helper function for it.

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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