Re: [PATCH 08/10] revert: Introduce HEAD, TODO files to persist state, plan

[Ramkumar Ramachandra <artagnon@gmail.com>]

Hi Jonathan and others,

Jonathan Nieder writes:
> Ramkumar Ramachandra wrote:
> Almost there.  To comfort overly-worried people like me that think we
> have not finished converted all die() calls yet, wouldn't this need to
> look like
>
>        persist_head(head);
>        while ((commit = ...)) {
>                int status_or_error;
>
>                /*
>                 * Checkpoint.  If do_pick_commit exits, make sure the user
>                 * can still use "git cherry-pick --continue" to recover.
>                 */
>                persist_todo(revs.commits, opts);
>
>                status_or_error = do_pick_commit(...);
>                if (status_or_error)
>                        return status_or_error;
>        }
>
>        /* Success! */
>        remove_todo(opts);
>        remove_head();
>        return 0;

It's a little embarrassing, but I'm not able to figure out how to
persist the TODO early. prepare_revs() sets up the revision walker and
populates the rev_info struct: it contains a commit_list * in its
commits member, but I apparently can't access those directly -- I went
through some literature about revision walking and inspected how
get_revision must be used to iterate over all the individual commits.
Now, to persist the TODO, I need a commit_list to use: is there some
API I can use to avoid iterating over all the commits twice? Once to
populate the commit_list to persist the TODO, and the second time to
actually pick them?

Thanks.

-- Ram