[Libguestfs] [PATCH] btrfs_subvolume_show: fix root/toplevel check w/ btrfs-progs >= 4.4

[Richard W.M. Jones]

On Mon, Jan 25, 2016 at 07:55:36PM +0100, Pino Toscano wrote:
> In trfs-progs 4.4 the error message has been changed, and our check did
> not work anymore.  Yes, parsing user messages really sucks...
> ---
>  daemon/btrfs.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/daemon/btrfs.c b/daemon/btrfs.c
> index 85dbe00..c67af83 100644
> --- a/daemon/btrfs.c
> +++ b/daemon/btrfs.c
> @@ -1029,9 +1029,12 @@ do_btrfs_subvolume_show (const char *subvolume)
>    }
>  
>    /* If the path is the btrfs root, `btrfs subvolume show' reports:
> -   *   <path> is btrfs root
> +   *   <path> is btrfs root [in btrfs-progs < 4.4]
> +   *   <path> is toplevel subvolume
>     */
> -  if (out && strstr (out, "is btrfs root") != NULL) {
> +  if (out &&
> +      (strstr (out, "is btrfs root") != NULL ||
> +       strstr (out, "is toplevel subvolume") != NULL)) {
>      reply_with_error ("%s is btrfs root", subvolume);
>      return NULL;
>    }
> -- 

Yup - machine readable output FTW.

ACK.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://people.redhat.com/~rjones/virt-df/