Re: [PATCH v2 2/3] object-file: emit corruption errors when detected

[Junio C Hamano <gitster@pobox.com>]

Jonathan Tan <jonathantanmy@google.com> writes:

> Instead of relying on errno being preserved across function calls, teach
> do_oid_object_info_extended() to itself report object corruption when
> it first detects it. There are 3 types of corruption being detected:
>  - when a replacement object is missing
>  - when a loose object is corrupt
>  - when a packed object is corrupt and the object cannot be read
>    in another way
>
> Note that in the RHS of this patch's diff, a check for ENOENT that was
> introduced in 3ba7a06552 (A loose object is not corrupt if it cannot
> be read due to EMFILE, 2010-10-28) is also removed. The purpose of this
> check is to avoid a false report of corruption if the errno contains
> something like EMFILE (or anything that is not ENOENT), in which case
> a more generic report is presented. Because, as of this patch, we no
> longer rely on such a heuristic to determine corruption, but surface
> the error message at the point when we read something that we did not
> expect, this check is no longer necessary.
>
> Besides being more resilient, this also prepares for a future patch in
> which an indirect caller of do_oid_object_info_extended() will need
> such functionality.
>
> Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
> ---
>  object-file.c  | 63 ++++++++++++++++++++++++++------------------------
>  object-store.h |  3 +++
>  2 files changed, 36 insertions(+), 30 deletions(-)

The implementation looks very straight-forward.  Nicely done.