Re: [RFC PATCH] mkfs: allow specification of default options via configuration file

["Darrick J. Wong" <djwong@kernel.org>]

On Tue, May 19, 2026 at 01:43:28AM -0700, Christoph Hellwig wrote:
> On Thu, May 14, 2026 at 08:06:53AM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> > 
> > Ted asked for the ability to set default mkfs options, but to retain the
> > ability respecify options via a separate configuration file or cli
> > options.  This would be useful for running fstests with the default
> > featureset of (say) Linux 5.15 LTS, while still allowing individual
> > testcases to provide their own overrides.  It's certainly less messy
> > than what Ted does today, which is a bash script that copies the desired
> > config file and changes things.
> 
> Looks reasonable, do you have a test for it as well?

Somewhere, yeah :)

> > +static inline int
> > +getopt_mkfs(
> 
> I don't think there's much of a point in the inline here.
> 
> > +	int			argc,
> > +	char *const		argv[],
> > +	const struct option	*longopts,
> > +	int			*longindex)
> > +{
> > +	return getopt_long(argc, argv, "b:c:d:i:l:L:m:n:KNp:qr:s:CfV",
> > +			longopts, longindex);
> > +}
> 
> Why does this hardcode the short options, but requires the caller to
> pass in the long options (which are the same for both callers)?

long_options is a local variable which contains a pointer into cli,
which is another local variable in main().

I could have made a fugly macro with implicit variable access, but that
was yuck.

> > +	while ((c = getopt_mkfs(argc, argv, long_options, &option_index)) != EOF) {
> 
> Killing the long_opts would also avoid the overly long line here and in
> the other call site.

I could just shorten it to "lopts" or something.

> > +		if (c == 'c') {
> > +			parse_subopts(c, optarg, defcfg_subopt_tab, &cli);
> > +		}
> 
> Spurious braces.

Will fix.

--D