On Tue, Sep 10, 2013 at 11:35:54AM +0200, Igor Mammedov wrote:
> On Wed, 4 Sep 2013 13:48:35 +0300
> "Michael S. Tsirkin" <m...@redhat.com> wrote:
>
> > Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
> > ---
> > include/qemu/range.h | 17 +++++++++++++++++
> > 1 file changed, 17 insertions(+)
> >
> > diff --git a/include/qemu/range.h b/include/qemu/range.h
> > index 4a0780d..1c688ca 100644
> > --- a/include/qemu/range.h
> > +++ b/include/qemu/range.h
> > @@ -17,6 +17,23 @@ struct Range {
> > uint64_t end; /* 1 + the last byte. 0 if range empty or ends at
> > ~0x0LL. */
> > };
> >
> > +static inline void range_extend(Range *range, Range *extend_by)
> doc comment what it does pls.
>
> > +{
> > + if (!extend_by->begin && !extend_by->end) {
> > + return;
> > + }
> > + if (!range->begin && !range->end) {
> > + *range = *extend_by;
> > + return;
> > + }
> > + if (range->begin > extend_by->begin) {
> > + range->begin = extend_by->begin;
> > + }
> > + if (range->end - 1 < extend_by->end - 1) {
> (foo)->end could be 0 at this point leading to overflow when subtracted,
> is it intended to be so?
Absolutely - as the comment near this field definition states:
0 means region ends at ~0x0LL.
> > + range->end = extend_by->end;
> > + }
> > +}
> > +
> > /* Get last byte of a range from offset + length.
> > * Undefined for ranges that wrap around 0. */
> > static inline uint64_t range_get_last(uint64_t offset, uint64_t len)
>
