Re: [PATCH v2 13/18] libxl: make libxl_cd_insert "eject" + "insert"

[Ian Campbell <ian.campbell@citrix.com>]

On Wed, 2014-07-30 at 19:23 +0100, Wei Liu wrote:
> A "cdrom insert" is always processed as "eject" + "insert", with JSON
> config updated in between. So that we can know the correct state of
> CDROM later when we try to retrieve domain configuration: if xenstore is
> "empty", then CDROM is "empty"; otherwise use the information presented
> in JSON.

When you say "empty" do you mean literally that the xenstore nodes do
not exist or that one of them contains the string "empty"? If, as I
suspect, you mean the former then writing 
        if xenstore nodes are not present then CDROM is "empty"
would confuse me less.

> +    rc = libxl__cdrom_insert(ctx, domid, &empty, NULL);
> +    if (rc)
> +        goto out;
> +
> +    /* Optimisation: don't insert empty disk twice, and skip
> +     * manipulating JSON. */

Do we not need to update the JSON in this case to reflect that it is now
empty?

Ian/