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

From
Han-Wen Nienhuys <hanwen@google.com>
Date
Feb 21, 2022, 14:32 UTC
Message-ID
<CAFQ2z_OkZwvvxY=9A8cVGVEyM49oWXQA_4zngu1QnKce-zb2gQ@mail.gmail.com>
In-Reply-To
<xmqqee4159r6.fsf@gitster.g>
On Fri, Feb 18, 2022 at 12:55 AM Junio C Hamano <gitster@pobox.com> wrote:
Show 10 quoted lines
> > @@ -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.
Show 18 quoted lines
> > --- 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.

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Previous: Junio C HamanoNext: Han-Wen Nienhuys via GitGitGadget
Message 19 of 33 in “reftable: avoid reading and writing empty keys”
  1. 0/7 reftable: avoid reading and writing empty keysHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  2. 1/7 Documentation: object_id_len goes up to 31Han-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  3. 2/7 reftable: reject 0 object_id_lenHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  4. 3/7 reftable: add a test that verifies that writing empty keys failsHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  5. 4/7 reftable: avoid writing empty keys at the block layerHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  6. Junio C HamanoJan 14, 2022
  7. Han-Wen NienhuysJan 17, 2022
  8. Junio C HamanoJan 17, 2022
  9. 5/7 reftable: ensure that obj_id_len is >= 2 on writingHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  10. 6/7 reftable: add test for length of disambiguating prefixHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  11. 7/7 reftable: rename writer_stats to reftable_writer_statsHan-Wen Nienhuys via GitGitGadget, Jan 12, 2022
  12. 0/7 reftable: avoid reading and writing empty keysHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  13. 1/7 Documentation: object_id_len goes up to 31Han-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  14. 2/7 reftable: reject 0 object_id_lenHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  15. Junio C HamanoFeb 18, 2022
  16. 3/7 reftable: add a test that verifies that writing empty keys failsHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  17. 4/7 reftable: avoid writing empty keys at the block layerHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  18. Junio C HamanoFeb 17, 2022
  19. Han-Wen NienhuysFeb 21, 2022
  20. 5/7 reftable: ensure that obj_id_len is >= 2 on writingHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  21. Junio C HamanoFeb 18, 2022
  22. 6/7 reftable: add test for length of disambiguating prefixHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  23. 7/7 reftable: rename writer_stats to reftable_writer_statsHan-Wen Nienhuys via GitGitGadget, Feb 17, 2022
  24. Junio C HamanoFeb 18, 2022
  25. 0/7 reftable: avoid reading and writing empty keysHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  26. 2/7 reftable: reject 0 object_id_lenHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  27. 1/7 Documentation: object_id_len goes up to 31Han-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  28. 4/7 reftable: avoid writing empty keys at the block layerHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  29. 3/7 reftable: add a test that verifies that writing empty keys failsHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  30. 5/7 reftable: ensure that obj_id_len is >= 2 on writingHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  31. 6/7 reftable: add test for length of disambiguating prefixHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  32. 7/7 reftable: rename writer_stats to reftable_writer_statsHan-Wen Nienhuys via GitGitGadget, Feb 21, 2022
  33. Junio C HamanoFeb 23, 2022

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