[Libguestfs] [PATCH] drives: force format=raw for /dev/null dummy drives

[Richard W.M. Jones]

On Wed, May 18, 2016 at 05:28:12PM +0200, Pino Toscano wrote:
> When creating the dummy scratch disk for a /dev/null drive, force its
> format as raw if it was not specified already.  After all, raw was
> already the only format allowed for this kind of drives, so it makes
> sense to specify the format explicitly and avoid the autodetection in
> qemu.
> ---
>  src/drives.c | 12 +++++++++---
>  1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/src/drives.c b/src/drives.c
> index c55b87e..1a4ae27 100644
> --- a/src/drives.c
> +++ b/src/drives.c
> @@ -410,9 +410,15 @@ create_drive_dev_null (guestfs_h *g,
>  {
>    CLEANUP_FREE char *tmpfile = NULL;
>  
> -  if (data->format && STRNEQ (data->format, "raw")) {
> -    error (g, _("for device '/dev/null', format must be 'raw'"));
> -    return NULL;
> +  if (data->format) {
> +    if (data->format && STRNEQ (data->format, "raw")) {
> +      error (g, _("for device '/dev/null', format must be 'raw'"));
> +      return NULL;
> +    }
> +  } else {
> +    /* Manual set format=raw for /dev/null drives, if that was not
> +     * already manually specified.  */
> +    data->format = "raw";
>    }
>  
>    if (guestfs_int_lazy_make_tmpdir (g) == -1)
> -- 
> 2.5.5

Makes sense, ACK.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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