Re: [PATCH v3 2/4] qemu-img: make --block-size optional for compare --stat

[Vladimir Sementsov-Ogievskiy]

29.10.2021 23:32, Eric Blake wrote:
> On Thu, Oct 28, 2021 at 12:24:39PM +0200, Vladimir Sementsov-Ogievskiy wrote:
> > Let's detect block-size automatically if not specified by user:
> >
> >   If both files define cluster-size, use minimum to be more precise.
> >   If both files don't specify cluster-size, use default of 64K
> >   If only one file specify cluster-size, just use it.
> >
> > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> > ---
> >   docs/tools/qemu-img.rst |  7 +++-
> >   qemu-img.c              | 71 +++++++++++++++++++++++++++++++++++++----
> >   qemu-img-cmds.hx        |  4 +--
> >   3 files changed, 72 insertions(+), 10 deletions(-)
>
> Reviewed-by: Eric Blake <eblake@redhat.com>
>
> > +    if (cluster_size1 > 0 && cluster_size2 > 0) {
> > +        if (cluster_size1 == cluster_size2) {
> > +            block_size = cluster_size1;
> > +        } else {
> > +            block_size = MIN(cluster_size1, cluster_size2);
> > +            qprintf(quiet, "%s and %s have different cluster sizes: %d and %d "
> > +                    "respectively. Using minimum as block-size for "
> > +                    "accuracy: %d. %s\n",
> > +                    fname1, fname2, cluster_size1,
> > +                    cluster_size2, block_size, note);
>
> Results in a long line; I don't know if it's worth trying to wrap it
> (if we had a generic utility function that took arbitrary text, then
> outputs it wrapped to the user's current terminal column width, I'd
> suggest using that instead - but that's NOT something I expect you to
> write, and I don't know if glib has such a utility).

Hmm. But long lines printed to the terminal are wrapped by terminal 
automatically, so we don't need to wrap to terminal width by hand..

--
Best regards,
Vladimir