On Fri, 12 Nov 2010 15:16:33 +0100 Markus Armbruster <arm...@redhat.com> wrote:
> Luiz Capitulino <lcapitul...@redhat.com> writes: > > > On Fri, 12 Nov 2010 11:21:57 +0100 > > Markus Armbruster <arm...@redhat.com> wrote: > > > >> Luiz Capitulino <lcapitul...@redhat.com> writes: > [...] > >> > +QString *qemu_chr_mem_to_qs(CharDriverState *chr) > >> > +{ > >> > + MemoryDriver *d = chr->opaque; > >> > + > >> > + if (d->outbuf_size == 0) { > >> > + return qstring_new(); > >> > + } > >> > >> Why is this necessary? Is qstring_from_substr() broken for empty > >> substrings? If it is, it ought to be fixed! > > > > qstring_from_substr() takes a character range; outbuf_size stores a size, > > not a string length. So we do: > > > >> > + return qstring_from_substr((char *) d->outbuf, 0, d->outbuf_size - > >> > 1); > > > > If outbuf_size is 0, we'll be passing a negative value down. > > What's wrong with that? Although it's going to work with the current QString implementation, I don't think it's it's a good idea to rely on a negative index. Maybe, we could have: return qstring_from_substr((char *) d->outbuf, 0, d->outbuf_size > 0 ? d->outbuf_size - 1 : 0); A bit harder to read, but makes the function smaller.