[Mesa-dev] [PATCH 5/5] [v2] gbm: Export a per plane getter for offset

[Daniel Stone]

Hi,

On 8 March 2017 at 05:31, Ben Widawsky <ben at bwidawsk.net> wrote:
> Unlike stride, there was no previous offset getter, so it can be right
> on the first try.
>
> v2: Return EINVAL when plane is greater than total planes to make it
> match the similar APIs.
> Avoid leak after fromPlanar (Daniel)
> Make sure when getting offsets we consider dumb images (Daniel)
>
> v3: Use Jason's recommendation for handling the non-planar case.
>
> v4: Return int64_t so we can get real errors

I really wish I'd caught this earlier. :(

Returning int64_t is annoying because the relevant interface demands
we need uint32_t, so we need to do casts in users. Given that the
offset is useless without the handle/fd, and we have real error values
for those (0 for handle, -1 for fd) which don't require casts, I'd
much rather this was just a uint32_t returning 0 on failure.

Oh well. If it's too late to change then fine, but if we could change
it, it would make life a little easier.

Sorry for the delay ...

Cheers,
Daniel