Re: [PATCH v6 1/2] libxl: Introduce functions to add and remove USB devices to an HVM guest

[Anthony PERARD <anthony.perard@citrix.com>]

On 19/04/13 16:59, George Dunlap wrote:
> diff --git a/tools/libxl/libxl_qmp.c b/tools/libxl/libxl_qmp.c
> index 644d2c0..9ad3e59 100644
> --- a/tools/libxl/libxl_qmp.c
> +++ b/tools/libxl/libxl_qmp.c
> @@ -42,6 +42,7 @@
>
>  #define QMP_RECEIVE_BUFFER_SIZE 4096
>  #define PCI_PT_QDEV_ID "pci-pt-%02x_%02x.%01x"
> +#define HOST_USB_QDEV_ID "usb-hostdev-%04x.%04x"
>
>  typedef int (*qmp_callback_t)(libxl__qmp_handler *qmp,
>                                const libxl__json_object *tree,
> @@ -929,6 +930,70 @@ int libxl__qmp_insert_cdrom(libxl__gc *gc, int domid,
>      }
>  }
>
> +static int libxl__qmp_usb_hostdev_add(libxl__gc *gc, int domid,
> +                                      libxl__device_usb *dev)
> +{
> +    libxl__json_object *args = NULL;
> +    char *id;
> +
> +    id = GCSPRINTF(HOST_USB_QDEV_ID,
> +                   (uint16_t)dev->u.hostdev.hostbus,
> +                   (uint16_t)dev->u.hostdev.hostaddr);
> +
> +    qmp_parameters_add_string(gc, &args, "driver", "usb-host");
> +    QMP_PARAMETERS_SPRINTF(&args, "hostbus", "0x%x",
dev->u.hostdev.hostbus);
> +    QMP_PARAMETERS_SPRINTF(&args, "hostaddr", "0x%x",
dev->u.hostdev.hostaddr);
> +
> +    qmp_parameters_add_string(gc, &args, "id", id);

You can use QMP_PARAMETERS_SPRINTF here instead of having a separate
GCSPRINTF call. The former do the same call to sprintf as the later.

> +
> +    return qmp_run_command(gc, domid, "device_add", args, NULL, NULL);
> +}
> +
> +int libxl__qmp_usb_add(libxl__gc *gc, int domid, libxl__device_usb
*usbdev)
> +{
> +    int rc;
> +    switch (usbdev->type) {
> +    case LIBXL_DEVICE_USB_TYPE_HOSTDEV:
> +        rc = libxl__qmp_usb_hostdev_add(gc, domid, usbdev);
> +        break;
> +    default:
> +        return ERROR_INVAL;
> +    }
> +    return rc;
> +}
> +
> +
> +static int libxl__qmp_usb_hostdev_remove(libxl__gc *gc, int domid,
> +                                         libxl__device_usb *dev)
> +{
> +    libxl__json_object *args = NULL;
> +    char *id;
> +
> +    id = GCSPRINTF(HOST_USB_QDEV_ID,
> +                   (uint16_t)dev->u.hostdev.hostbus,
> +                   (uint16_t)dev->u.hostdev.hostaddr);
> +
> +    qmp_parameters_add_string(gc, &args, "id", id);
> +
> +    return qmp_run_command(gc, domid, "device_del", args, NULL, NULL);

There is already a "device_del" which can be called:
static int qmp_device_del(libxl__gc *gc, int domid, char *id);

-- 
Anthony PERARD