Re: [PATCH v3 16/19] sha1_file: introduce an nth_packed_object_oid function

> 
> 
> On 18/02/17 00:06, brian m. carlson wrote:
> > There are places in the code where we would like to provide a struct
> > object_id *, yet read the hash directly from the pack.  Provide an
> > nth_packed_object_oid function that is similar to the
> > nth_packed_object_sha1 function.
> > 
> > In order to avoid a potentially invalid cast, nth_packed_object_oid
> > provides a variable into which to store the value, which it returns on
> > success; on error, it returns NULL, as nth_packed_object_sha1 does.
> > 
> > Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
> > ---
> >  cache.h     |  6 ++++++
> >  sha1_file.c | 17 ++++++++++++++---
> >  2 files changed, 20 insertions(+), 3 deletions(-)
> > 
> > diff --git a/cache.h b/cache.h
> > index e03a672d15..4f3bfc5ee7 100644
> > --- a/cache.h
> > +++ b/cache.h
> > @@ -1608,6 +1608,12 @@ extern void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
> >   * error.
> >   */
> >  extern const unsigned char *nth_packed_object_sha1(struct packed_git *, uint32_t n);
> > +/*
> > + * Like nth_packed_object_oid, but write the data into the object specified by
>                              ^^^
> ... Like nth_packed_object_sha1, but ...