[pacman-dev] [PATCH] libalpm: fix documentation for alpm_pkg_mtree_next

[Dave Reisner]

On Fri, Jun 14, 2019 at 02:19:52PM +0100, Morgan Adamiec wrote:
> On Fri, 14 Jun 2019 at 14:09, Dave Reisner <d at falconindy.com> wrote:
> >
> > On Fri, Jun 14, 2019 at 02:51:14AM +0100, morganamilo wrote:
> > > libarchive uses 1 for EOF, not 0. Instead of using the actual ints, use
> > > libarchive's error codes.
> > > ---
> > >
> > > By the way, not familiar with doxygen. Is my wording fine or is there
> > > some built in "see also" functionality?
> > >
> > > diff --git a/lib/libalpm/alpm.h b/lib/libalpm/alpm.h
> > > index ffb2ad96..ece894cf 100644
> > > --- a/lib/libalpm/alpm.h
> > > +++ b/lib/libalpm/alpm.h
> > > @@ -1326,7 +1326,8 @@ struct archive *alpm_pkg_mtree_open(alpm_pkg_t *pkg);
> > >   * @param pkg the package that the mtree file is being read from
> > >   * @param archive the archive structure reading from the mtree file
> > >   * @param entry an archive_entry to store the entry header information
> > > - * @return 0 if end of archive is reached, non-zero otherwise.
> > > + * @return ARCHIVE_OK on success, ARCHIVE_EOF if end of archive is reached,
> > > + * otherwise an error occured (see archive.h).
> >
> > Please, no. Let's not leak details from libarchive in our own API.
> >
> > >   */
> > >  int alpm_pkg_mtree_next(const alpm_pkg_t *pkg, struct archive *archive,
> > >               struct archive_entry **entry);
> > > --
> > > 2.21.0
> 
> Why not? The return value is exactly that. If libarchive's return
> codes suddenly changed then so would libalpms's. Plus pacman itself
> already uses ARCHIVE_OK to check the return code. And finally if we
> did not depend on magic numbers then the doc wouldn't be wrong in the
> first place.

Because users of libalpm should only need to understand libalpm and not
concern themselves with details of libarchive. Exposing ARCHIVE_* in
libalpm is a leaky abstraction.

If the code is broken (and it sounds like it is), then it should be
fixed along with the documentation.