[libvirt] [PATCH v1 25/40] util: usb: use VIR_AUTOPTR for aggregate types

[Erik Skultety]

On Sat, Jul 21, 2018 at 05:36:57PM +0530, Sukrit Bhatnagar wrote:
> By making use of GNU C's cleanup attribute handled by the
> VIR_AUTOPTR macro for declaring aggregate pointer variables,
> majority of the calls to *Free functions can be dropped, which
> in turn leads to getting rid of most of our cleanup sections.
>
> Signed-off-by: Sukrit Bhatnagar <skrtbhtngr at gmail.com>
> ---
>  src/util/virusb.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/src/util/virusb.c b/src/util/virusb.c
> index c14683f..cfeac51 100644
> --- a/src/util/virusb.c
> +++ b/src/util/virusb.c
> @@ -508,8 +508,7 @@ void
>  virUSBDeviceListDel(virUSBDeviceListPtr list,
>                      virUSBDevicePtr dev)
>  {
> -    virUSBDevicePtr ret = virUSBDeviceListSteal(list, dev);
> -    virUSBDeviceFree(ret);
> +    VIR_AUTOPTR(virUSBDevice) ret = virUSBDeviceListSteal(list, dev);
>  }
>

Technically, there's also a virUSBDevicePtr instance in virUSBDeviceSearch that
could be converted to VIR_AUTOPTR, but virUSBDeviceListAdd would have to take a
double pointer to @dev instead of a single pointer. A bit more background
info - the current issue is that virUSBDeviceListAdd calls our
VIR_APPEND_ELEMENT helper which does clear the original pointer which we could
utilize here, but not while passing a single pointer.
Not a deal breaker, though, it's just a nice to have, since you're already
working in this area, because I don't suppose we'd make such a change any time
soon after your assignment is over.

(regardless)
Reviewed-by: Erik Skultety <eskultet at redhat.com>