[libcamera-devel] [PATCH v3 2/3] libcamera: Add V4L2 Device object

[Jacopo Mondi]

Hi Niklas,

On Wed, Jan 16, 2019 at 03:54:23PM +0100, Niklas Söderlund wrote:
> Hi Kieran, Jacopo
>
>
>
> On 2019-01-16 09:44:55 +0100, Jacopo Mondi wrote:
>
> [snip]
>
> > > +int V4L2Device::open()
> > > +{
> > > +	int ret;
> > > +
> > > +	if (isOpen()) {
> > > +		LOG(Error) << "Device already open";
> > > +		return -EBUSY;
> > > +	}
> > > +
> > > +	ret = ::open(devnode_.c_str(), O_RDWR);
> > > +	if (ret < 0) {
> > > +		ret = -errno;
> > > +		LOG(Error) << "Failed to open V4L2 device " << devnode_
> > > +			   << " : " << strerror(ret);
> >
> > strerror(-ret)
> >
> > Even if in this case you could have used errno directly. Sorry, my
> > comment might has mis-lead you
>
> No you can't use errno in the call to strerror() as it might already
> have been been changed by the previous strings passed to LOG(Error),
> unfortunately it needs to be cached.
>

Right, that's why we standardized on that patter... sorry, I've been
sloppy commenting this...

Kieran, pay attention to this in the IOCTL error handling you have a
few lines below these ones...

Thanks
  j

> >
> > > +		return ret;
> > > +	}
>
> --
> Regards,
> Niklas Söderlund
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <https://lists.libcamera.org/pipermail/libcamera-devel/attachments/20190116/1d972698/attachment.sig>