Re: [PATCH v2 4/7] reftable: avoid writing empty keys at the block layer

[Han-Wen Nienhuys <hanwen@google.com>]

On Fri, Feb 18, 2022 at 12:55 AM Junio C Hamano <gitster@pobox.com> wrote:
> > @@ -358,6 +363,8 @@ int block_reader_first_key(struct block_reader *br, struct strbuf *key)
> >       int n = reftable_decode_key(key, &extra, empty, in);
> >       if (n < 0)
> >               return n;
> > +     if (!key->len)
> > +             return -1;
>
> It is curious that this gets a different error out of the same
> sequence, i.e. decode-key did not return an error but the length of
> the key happens to be 0, not FORMAT_ERROR.

fixed.

> > --- a/reftable/writer.c
> > +++ b/reftable/writer.c
> > @@ -240,14 +240,13 @@ static int writer_add_record(struct reftable_writer *w,
> >
> >       writer_reinit_block_writer(w, reftable_record_type(rec));
> >       err = block_writer_add(w->block_writer, rec);
> > -     if (err < 0) {
> > +     if (err == -1) {
> >               /* we are writing into memory, so an error can only mean it
> >                * doesn't fit. */
> >               err = REFTABLE_ENTRY_TOO_BIG_ERROR;
> >               goto done;
> >       }
> >
> > -     err = 0;
>
> Is this "doesn't fit" related to "we catch 0-length keys", or an
> unrelated fix was included in this step by "rebase -i" mistake?

We don't want to reinterpret API_ERROR (from block_writer_add) as
ENTRY_TOO_BIG_ERROR, so we have to tweak the condition here.

-- 
Han-Wen Nienhuys - Google Munich
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