Re: [PATCH] create: Always check for sparseness if '--hole-detection=raw'

[Doug Anderson]

Hi,

On Mon, Feb 26, 2024 at 5:46 PM Douglas Anderson <dianders@chromium.org> wrote:
>
> If we're using 'hole-detection=raw' then we're going to be manually
> looking for sparseness in our files. We don't really care about
> whether the OS thinks they're sparse, so don't do the check about the
> number of blocks the OS thinks the file takes.
>
> Without this change if I use "tar --hole-detection=raw -cf" to tar up
> a file that's got lots of zeros (but isn't marked by the OS as
> sparse), when I untar the file then it's still not sparse. With this
> change then the zeros are correctly transformed into sparseness.
>
> ---
> This is the same patch that was submitted via Savannah [1], but I'm
> not terribly familiar with the process for submitting tar patches so I
> thought I'd maybe post to this list too. Sorry if I've got this wrong.
>
> [1] https://savannah.gnu.org/patch/index.php?10432
> ---
>  src/create.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

I'm hoping for some sort of response, either positive or negative,
about this patch. I'm happy to make changes and submit a new version
if there is something folks don't like about it. IMO this is fixing a
real problem with the "--hole-detection=raw" mode and it would be nice
to get it in. If people disagree I'm happy to discuss or alternatively
go back to the drawing board and try to find a different way to solve
my problem.

If people simply need more time to evaluate this patch then I can also
step back and wait patiently. I'm not trying to be a pest but am
trying to figure out how to move forward.

Please let me know! Thanks!

-Doug