[PATCH 0/7] reftable: fixes and optimizations (pt.2)

Hi,

this is the second set of patches that fixes bugs and performs some slight memory optimizations. The series builds on top of c0cadb0576, which has been merged to `next`.

The series is structured as follows:

  - Patch 1: some hardening to not corrupt the reftable stack on
    compaction.

  - Patch 2: fix corruption of a reftable when writing multiple indices.

  - Patches 3 - 7: various smallish refactorings to optimize memory
    usage. Overall these reduce allocations when iterating many refs by
    almost 85%.

Thanks in advance for your review!

Patrick

Patrick Steinhardt (7):
  reftable/stack: do not overwrite errors when compacting
  reftable/writer: fix index corruption when writing multiple indices
  reftable/record: constify some parts of the interface
  reftable/record: store "val1" hashes as static arrays
  reftable/record: store "val2" hashes as static arrays
  reftable/merged: really reuse buffers to compute record keys
  reftable/merged: transfer ownership of records when iterating

 reftable/block_test.c      |   4 +-
 reftable/merged.c          |   8 +--
 reftable/merged_test.c     |  16 +++---
 reftable/readwrite_test.c  | 103 +++++++++++++++++++++++++++++++------
 reftable/record.c          |  17 ++----
 reftable/record_test.c     |   5 --
 reftable/reftable-record.h |  10 ++--
 reftable/stack.c           |  20 +++----
 reftable/stack_test.c      |   2 -
 reftable/writer.c          |   4 +-
 10 files changed, 117 insertions(+), 72 deletions(-)

base-commit: c0cadb0576d4920915eb3bd38a7d1abfcbd25f98