[libcamera-devel] [PATCH 5/5] libcamera: v4l2_device: Provide V4L2 Log helper

[Kieran Bingham]

Hi Laurent,

On 08/02/2019 17:33, Laurent Pinchart wrote:
> Hi Kieran,
> 
> Thank you for the patch.
> 
> On Thu, Feb 07, 2019 at 09:21:19PM +0000, Kieran Bingham wrote:
>> Add a V4L2DEVICE_LOG Macro helper to prepend the V4L2 Video Device node to
>> every log output.  This is particularly useful when more than one V4L2Device is
>> utilised in the system.
>>
>> Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> 
> I've sent a patch that adds a Loggable class, it should cover your use
> case in a more generic way.

Sure, I'll just drop this.
--
Kieran


> 
>> ---
>>  src/libcamera/v4l2_device.cpp | 48 +++++++++++++++++++----------------
>>  1 file changed, 26 insertions(+), 22 deletions(-)
>>
>> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp
>> index c2e4d0ea8db2..ce977613ff20 100644
>> --- a/src/libcamera/v4l2_device.cpp
>> +++ b/src/libcamera/v4l2_device.cpp
>> @@ -28,6 +28,8 @@ namespace libcamera {
>>  
>>  LOG_DEFINE_CATEGORY(V4L2)
>>  
>> +#define V4L2DEVICE_LOG(severity) LOG(V4L2, severity) << deviceNode_ << ": "
>> +
>>  /**
>>   * \struct V4L2Capability
>>   * \brief struct v4l2_capability object wrapper and helpers
>> @@ -254,14 +256,14 @@ int V4L2Device::open()
>>  	int ret;
>>  
>>  	if (isOpen()) {
>> -		LOG(V4L2, Error) << "Device already open";
>> +		V4L2DEVICE_LOG(Error) << "Device already open";
>>  		return -EBUSY;
>>  	}
>>  
>>  	ret = ::open(deviceNode_.c_str(), O_RDWR | O_NONBLOCK);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to open V4L2 device '" << deviceNode_
>>  			<< "': " << strerror(-ret);
>>  		return ret;
>> @@ -271,24 +273,25 @@ int V4L2Device::open()
>>  	ret = ioctl(fd_, VIDIOC_QUERYCAP, &caps_);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to query device capabilities: "
>>  			<< strerror(-ret);
>>  		return ret;
>>  	}
>>  
>> -	LOG(V4L2, Debug)
>> +	V4L2DEVICE_LOG(Debug)
>>  		<< "Opened '" << deviceNode_ << "' "
>>  		<< caps_.bus_info() << ": " << caps_.driver()
>>  		<< ": " << caps_.card();
>>  
>>  	if (!caps_.isCapture() && !caps_.isOutput()) {
>> -		LOG(V4L2, Debug) << "Device is not a supported type";
>> +		V4L2DEVICE_LOG(Debug) << "Device is not a supported type";
>>  		return -EINVAL;
>>  	}
>>  
>>  	if (!caps_.hasStreaming()) {
>> -		LOG(V4L2, Error) << "Device does not support streaming I/O";
>> +		V4L2DEVICE_LOG(Error)
>> +			<< "Device does not support streaming I/O";
>>  		return -EINVAL;
>>  	}
>>  
>> @@ -513,13 +516,13 @@ int V4L2Device::requestBuffers(unsigned int count)
>>  	ret = ioctl(fd_, VIDIOC_REQBUFS, &rb);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Unable to request " << count << " buffers: "
>>  			<< strerror(-ret);
>>  		return ret;
>>  	}
>>  
>> -	LOG(V4L2, Debug)
>> +	V4L2DEVICE_LOG(Debug)
>>  		<< deviceNode_ << ":" << rb.count << " buffers requested.";
>>  
>>  	return rb.count;
>> @@ -545,7 +548,8 @@ int V4L2Device::exportBuffers(BufferPool *pool)
>>  
>>  	allocatedBuffers = ret;
>>  	if (allocatedBuffers < pool->count()) {
>> -		LOG(V4L2, Error) << "Not enough buffers provided by V4L2Device";
>> +		V4L2DEVICE_LOG(Error)
>> +			<< "Not enough buffers provided by V4L2Device";
>>  		requestBuffers(0);
>>  		return -ENOMEM;
>>  	}
>> @@ -565,7 +569,7 @@ int V4L2Device::exportBuffers(BufferPool *pool)
>>  		ret = ioctl(fd_, VIDIOC_QUERYBUF, &buf);
>>  		if (ret < 0) {
>>  			ret = -errno;
>> -			LOG(V4L2, Error)
>> +			V4L2DEVICE_LOG(Error)
>>  				<< "Unable to query buffer " << i << ": "
>>  				<< strerror(-ret);
>>  			break;
>> @@ -583,7 +587,7 @@ int V4L2Device::exportBuffers(BufferPool *pool)
>>  		}
>>  
>>  		if (ret) {
>> -			LOG(V4L2, Error) << "Failed to create plane";
>> +			V4L2DEVICE_LOG(Error) << "Failed to create plane";
>>  			break;
>>  		}
>>  	}
>> @@ -605,7 +609,7 @@ int V4L2Device::createPlane(Buffer *buffer, unsigned int planeIndex,
>>  	struct v4l2_exportbuffer expbuf = {};
>>  	int ret;
>>  
>> -	LOG(V4L2, Debug)
>> +	V4L2DEVICE_LOG(Debug)
>>  		<< "Buffer " << buffer->index()
>>  		<< " plane " << planeIndex
>>  		<< ": length=" << length;
>> @@ -618,7 +622,7 @@ int V4L2Device::createPlane(Buffer *buffer, unsigned int planeIndex,
>>  	ret = ioctl(fd_, VIDIOC_EXPBUF, &expbuf);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to export buffer: " << strerror(-ret);
>>  		return ret;
>>  	}
>> @@ -648,13 +652,13 @@ int V4L2Device::importBuffers(BufferPool *pool)
>>  
>>  	allocatedBuffers = ret;
>>  	if (allocatedBuffers < pool->count()) {
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Not enough buffers provided by V4L2Device";
>>  		requestBuffers(0);
>>  		return -ENOMEM;
>>  	}
>>  
>> -	LOG(V4L2, Debug) << "Device using an externally provided pool";
>> +	V4L2DEVICE_LOG(Debug) << "Device using an externally provided pool";
>>  	bufferPool_ = pool;
>>  
>>  	return 0;
>> @@ -665,7 +669,7 @@ int V4L2Device::importBuffers(BufferPool *pool)
>>   */
>>  int V4L2Device::releaseBuffers()
>>  {
>> -	LOG(V4L2, Debug) << "Releasing bufferPool";
>> +	V4L2DEVICE_LOG(Debug) << "Releasing bufferPool";
>>  
>>  	requestBuffers(0);
>>  	bufferPool_ = nullptr;
>> @@ -715,12 +719,12 @@ int V4L2Device::queueBuffer(Buffer *buffer)
>>  		buf.m.planes = planes;
>>  	}
>>  
>> -	LOG(V4L2, Debug) << "Queueing buffer " << buf.index;
>> +	V4L2DEVICE_LOG(Debug) << "Queueing buffer " << buf.index;
>>  
>>  	ret = ioctl(fd_, VIDIOC_QBUF, &buf);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to queue buffer " << buf.index << ": "
>>  			<< strerror(-ret);
>>  		return ret;
>> @@ -757,7 +761,7 @@ Buffer *V4L2Device::dequeueBuffer()
>>  	ret = ioctl(fd_, VIDIOC_DQBUF, &buf);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to dequeue buffer: " << strerror(-ret);
>>  		return nullptr;
>>  	}
>> @@ -793,7 +797,7 @@ void V4L2Device::bufferAvailable(EventNotifier *notifier)
>>  	if (!buffer)
>>  		return;
>>  
>> -	LOG(V4L2, Debug) << "Buffer " << buffer->index() << " is available";
>> +	V4L2DEVICE_LOG(Debug) << "Buffer " << buffer->index() << " is available";
>>  
>>  	/* Notify anyone listening to the device. */
>>  	bufferReady.emit(buffer);
>> @@ -819,7 +823,7 @@ int V4L2Device::streamOn()
>>  	ret = ioctl(fd_, VIDIOC_STREAMON, &bufferType_);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to start streaming: " << strerror(-ret);
>>  		return ret;
>>  	}
>> @@ -841,7 +845,7 @@ int V4L2Device::streamOff()
>>  	ret = ioctl(fd_, VIDIOC_STREAMOFF, &bufferType_);
>>  	if (ret < 0) {
>>  		ret = -errno;
>> -		LOG(V4L2, Error)
>> +		V4L2DEVICE_LOG(Error)
>>  			<< "Failed to stop streaming: " << strerror(-ret);
>>  		return ret;
>>  	}
> 

-- 
Regards
--
Kieran