Re: [PATCH 43/46] qdev: Smooth error checking manually

[Eric Blake]

On 6/24/20 11:43 AM, Markus Armbruster wrote:
> When foo(..., &err) is followed by error_propagate(errp, err), we can
> often just as well do foo(..., errp).  The previous commit did that
> for simple cases with Coccinelle.  Do it for one more manually.
>
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---
>   hw/block/fdc.c | 8 +++-----
>   1 file changed, 3 insertions(+), 5 deletions(-)

> @@ -2566,11 +2566,9 @@ static void fdctrl_connect_drives(FDCtrl *fdctrl, 
> DeviceState *fdc_dev,
>           blk_ref(blk);
>           blk_detach_dev(blk, fdc_dev);
>           fdctrl->qdev_for_drives[i].blk = NULL;
> -        qdev_prop_set_drive_err(dev, "drive", blk, &local_err);
> +        ok = qdev_prop_set_drive_err(dev, "drive", blk, errp);
>           blk_unref(blk);

Perhaps some glib g_auto* magic could make this even easier (to mark a 
variable to be blk_unref'd when it goes out of scope).  But for now, 
your pattern is fine.

> -
> -        if (local_err) {
> -            error_propagate(errp, local_err);
> +        if (!ok) {
>               return;
>           }
>   

Reviewed-by: Eric Blake <eblake@redhat.com>

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org