[libcamera-devel] [PATCH v5 4/4] libcamera: v4l2: Standardize return value checks

[Laurent Pinchart]

Hi Jacopo,

Thank you for the patch.

On Wed, Jun 19, 2019 at 01:05:48PM +0200, Jacopo Mondi wrote:
> Standardize all return values checks on the 'if (ret)' style where
> appropriate.

Just curious, why did you choose (ret) over (ret < 0) ? I would have
gone the other way around :-)

> 
> No functional changes intended.
> 
> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  src/libcamera/v4l2_subdevice.cpp   |  2 +-
>  src/libcamera/v4l2_videodevice.cpp | 18 +++++++++---------
>  2 files changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/src/libcamera/v4l2_subdevice.cpp b/src/libcamera/v4l2_subdevice.cpp
> index d0e1d717b26c..7f887e377c97 100644
> --- a/src/libcamera/v4l2_subdevice.cpp
> +++ b/src/libcamera/v4l2_subdevice.cpp
> @@ -340,7 +340,7 @@ int V4L2Subdevice::setSelection(unsigned int pad, unsigned int target,
>  	sel.r.height = rect->h;
>  
>  	int ret = ioctl(VIDIOC_SUBDEV_S_SELECTION, &sel);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Unable to set rectangle " << target << " on pad "
>  			<< pad << ": " << strerror(-ret);
> diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
> index bcbac79e82e9..d1409fcafa04 100644
> --- a/src/libcamera/v4l2_videodevice.cpp
> +++ b/src/libcamera/v4l2_videodevice.cpp
> @@ -305,11 +305,11 @@ int V4L2VideoDevice::open()
>  	int ret;
>  
>  	ret = V4L2Device::open(O_RDWR | O_NONBLOCK);
> -	if (ret < 0)
> +	if (ret)
>  		return ret;
>  
>  	ret = ioctl(VIDIOC_QUERYCAP, &caps_);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Failed to query device capabilities: "
>  			<< strerror(-ret);
> @@ -633,7 +633,7 @@ int V4L2VideoDevice::requestBuffers(unsigned int count)
>  	rb.memory = memoryType_;
>  
>  	ret = ioctl(VIDIOC_REQBUFS, &rb);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Unable to request " << count << " buffers: "
>  			<< strerror(-ret);
> @@ -684,7 +684,7 @@ int V4L2VideoDevice::exportBuffers(BufferPool *pool)
>  		buf.m.planes = planes;
>  
>  		ret = ioctl(VIDIOC_QUERYBUF, &buf);
> -		if (ret < 0) {
> +		if (ret) {
>  			LOG(V4L2, Error)
>  				<< "Unable to query buffer " << i << ": "
>  				<< strerror(-ret);
> @@ -736,7 +736,7 @@ int V4L2VideoDevice::createPlane(Buffer *buffer, unsigned int planeIndex,
>  	expbuf.flags = O_RDWR;
>  
>  	ret = ioctl(VIDIOC_EXPBUF, &expbuf);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Failed to export buffer: " << strerror(-ret);
>  		return ret;
> @@ -927,7 +927,7 @@ int V4L2VideoDevice::queueBuffer(Buffer *buffer)
>  	LOG(V4L2, Debug) << "Queueing buffer " << buf.index;
>  
>  	ret = ioctl(VIDIOC_QBUF, &buf);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Failed to queue buffer " << buf.index << ": "
>  			<< strerror(-ret);
> @@ -963,7 +963,7 @@ Buffer *V4L2VideoDevice::dequeueBuffer()
>  	}
>  
>  	ret = ioctl(VIDIOC_DQBUF, &buf);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Failed to dequeue buffer: " << strerror(-ret);
>  		return nullptr;
> @@ -1022,7 +1022,7 @@ int V4L2VideoDevice::streamOn()
>  	int ret;
>  
>  	ret = ioctl(VIDIOC_STREAMON, &bufferType_);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Failed to start streaming: " << strerror(-ret);
>  		return ret;
> @@ -1044,7 +1044,7 @@ int V4L2VideoDevice::streamOff()
>  	int ret;
>  
>  	ret = ioctl(VIDIOC_STREAMOFF, &bufferType_);
> -	if (ret < 0) {
> +	if (ret) {
>  		LOG(V4L2, Error)
>  			<< "Failed to stop streaming: " << strerror(-ret);
>  		return ret;

-- 
Regards,

Laurent Pinchart