Re: [REVIEW PATCH 01/14] V4L: Int if: Dummy slave

[Sakari Ailus <sakari.ailus@nokia.com>]

Mauro Carvalho Chehab wrote:
> On Mon, 12 Jan 2009 20:03:08 -0600
> "Aguirre Rodriguez, Sergio Alberto" <saaguirre@ti.com> wrote:
> 
>> +static struct v4l2_int_slave dummy_slave = {
>> +	/* Dummy pointer to avoid underflow in find_ioctl. */
>> +	.ioctls = (void *)0x80000000,
> 
> Why are you using here a magic number?

Not really a reason. It could be or actually perhaps anything equal to
or bigger than sizeof(struct v4l2_int_ioctl_desc) so that last doesn't
underflow:

         const struct v4l2_int_ioctl_desc *first = slave->ioctls;
         const struct v4l2_int_ioctl_desc *last =
                 first + slave->num_ioctls - 1;

num_ioctls is zero. See find_ioctl in drivers/media/video/v4l2-int-device.c.

I guess that should be changed to sizeof(struct v4l2_int_ioctl_desc).

-- 
Sakari Ailus
sakari.ailus@nokia.com