Commit graph

4 commits

Author SHA1 Message Date
Junio C Hamano
1c4411cce1 Merge branch 'cm/reftable-0-length-memset'
Code clean-up.

* cm/reftable-0-length-memset:
  reftable: avoid undefined behaviour breaking t0032
2022-05-04 09:51:29 -07:00
Carlo Marcelo Arenas Belón
e6b2582da3 reftable: avoid undefined behaviour breaking t0032
1214aa841b (reftable: add blocksource, an abstraction for random
access reads, 2021-10-07), makes the assumption that it is ok to
free a reftable_block pointing to NULL if the size is also set to
0, but implements that using a memset call that at least in glibc
based system will trigger a runtime exception if called with a
NULL pointer as its first parameter.

Avoid doing so by adding a conditional to check for the size in all
three identically looking functions that were affected, and therefore,
still allow memset to help catch callers that might incorrectly pass
a NULL pointer with a non zero size, but avoiding the exception for
the valid cases.

Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-04-15 09:24:02 -07:00
Han-Wen Nienhuys
27e27ee224 reftable: fix resource leak blocksource.c
This would be triggered in the unlikely event of fstat() failing on an
opened file.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-01-20 11:31:52 -08:00
Han-Wen Nienhuys
1214aa841b reftable: add blocksource, an abstraction for random access reads
The reftable format is usually used with files for storage. However, we abstract
away this using the blocksource data structure. This has two advantages:

* log blocks are zlib compressed, and handling them is simplified if we can
  discard byte segments from within the block layer.

* for unittests, it is useful to read and write in-memory. The blocksource
  allows us to abstract the data away from on-disk files.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00