Re: [PATCH] btrfs-progs: subvolume: output the prompt line only when the ioctl succeeded

[Boris Burkov <boris@bur.io>]

On Fri, Mar 01, 2024 at 01:56:31PM +0100, David Sterba wrote:
> On Tue, Feb 27, 2024 at 02:41:16PM +1030, Qu Wenruo wrote:
> > [BUG]
> > With the latest kernel patch to reject invalid qgroupids in
> > btrfs_qgroup_inherit structure, "btrfs subvolume create" or "btrfs
> > subvolume snapshot" can lead to the following output:
> > 
> >  # mkfs.btrfs -O quota -f $dev
> >  # mount $dev $mnt
> >  # btrfs subvolume create -i 2/0 $mnt/subv1
> >  Create subvolume '/mnt/btrfs/subv1'
> >  ERROR: cannot create subvolume: No such file or directory
> > 
> > The "btrfs subvolume" command output the first line, seemingly to
> > indicate a successful subvolume creation, then followed by an error
> > message.
> > 
> > This can be a little confusing on whether if the subvolume is created or
> > not.
> > 
> > [FIX]
> > Fix the output by only outputting the regular line if the ioctl
> > succeeded.
> > 
> > Signed-off-by: Qu Wenruo <wqu@suse.com>
> 
> Added to devel, thanks.

This patch breaks every test that creates snapshots or subvolumes and
expects the output in the outfile.

That's because it did:
s/Create a snapshot/Create snapshot/

Please run the tests when making changes! This failed on btrfs/001, so
it would have taken 1 second to see.