[libcamera-devel] [PATCH 07/10] libcamera: buffer: Add buffer completion status

[Niklas Söderlund]

Hi Laurent,

Thanks for your work.

On 2019-02-28 18:29:10 +0200, Laurent Pinchart wrote:
> Add a new field to the Buffer class to report its completion status,
> with a new cancel() method to mark the buffer as cancelled.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

Reviewed-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>

> ---
>  include/libcamera/buffer.h    | 10 ++++++++++
>  src/libcamera/buffer.cpp      | 35 +++++++++++++++++++++++++++++++++++
>  src/libcamera/v4l2_device.cpp |  2 ++
>  3 files changed, 47 insertions(+)
> 
> diff --git a/include/libcamera/buffer.h b/include/libcamera/buffer.h
> index dc9aaad12a81..f740ade9bb4f 100644
> --- a/include/libcamera/buffer.h
> +++ b/include/libcamera/buffer.h
> @@ -40,12 +40,19 @@ private:
>  class Buffer final
>  {
>  public:
> +	enum Status {
> +		BufferSuccess,
> +		BufferError,
> +		BufferCancelled,
> +	};
> +
>  	Buffer();
>  
>  	unsigned int index() const { return index_; }
>  	unsigned int bytesused() const { return bytesused_; }
>  	uint64_t timestamp() const { return timestamp_; }
>  	unsigned int sequence() const { return sequence_; }
> +	Status status() const { return status_; }
>  	std::vector<Plane> &planes() { return planes_; }
>  
>  	Signal<Buffer *> completed;
> @@ -54,10 +61,13 @@ private:
>  	friend class BufferPool;
>  	friend class V4L2Device;
>  
> +	void cancel();
> +
>  	unsigned int index_;
>  	unsigned int bytesused_;
>  	uint64_t timestamp_;
>  	unsigned int sequence_;
> +	Status status_;
>  
>  	std::vector<Plane> planes_;
>  };
> diff --git a/src/libcamera/buffer.cpp b/src/libcamera/buffer.cpp
> index 80dd9c854a4b..524eb47d4364 100644
> --- a/src/libcamera/buffer.cpp
> +++ b/src/libcamera/buffer.cpp
> @@ -181,6 +181,20 @@ void *Plane::mem()
>   * objects if the image format is multi-planar.
>   */
>  
> +/**
> + * \enum Buffer::Status
> + * Buffer completion status
> + * \var Buffer::BufferSuccess
> + * The buffer has completed with success and contains valid data. All its other
> + * metadata (such as bytesused(), timestamp() or sequence() number) are valid.
> + * \var Buffer::BufferError
> + * The buffer has completed with an error and doesn't contain valid data. Its
> + * other metadata are valid.
> + * \var Buffer::BufferCancelled
> + * The buffer has been cancelled due to capture stop. Its other metadata are
> + * invalid and shall not be used.
> + */
> +
>  Buffer::Buffer()
>  	: index_(-1)
>  {
> @@ -229,6 +243,27 @@ Buffer::Buffer()
>   * \return Sequence number of the buffer
>   */
>  
> +/**
> + * \fn Buffer::status()
> + * \brief Retrieve the buffer status
> + *
> + * The buffer status reports whether the buffer has completed successfully
> + * (BufferSuccess) or if an error occurred (BufferError).
> + *
> + * \return The buffer status
> + */
> +
> +/**
> + * \brief Mark a buffer as cancel by setting its status to BufferCancelled
> + */
> +void Buffer::cancel()
> +{
> +	bytesused_ = 0;
> +	timestamp_ = 0;
> +	sequence_ = 0;
> +	status_ = BufferCancelled;
> +}
> +
>  /**
>   * \class BufferPool
>   * \brief A pool of buffers
> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp
> index 31200a6e7d6f..054499e4b888 100644
> --- a/src/libcamera/v4l2_device.cpp
> +++ b/src/libcamera/v4l2_device.cpp
> @@ -793,6 +793,8 @@ Buffer *V4L2Device::dequeueBuffer()
>  	buffer->timestamp_ = buf.timestamp.tv_sec * 1000000000ULL
>  			   + buf.timestamp.tv_usec * 1000ULL;
>  	buffer->sequence_ = buf.sequence;
> +	buffer->status_ = buf.flags & V4L2_BUF_FLAG_ERROR
> +			? Buffer::BufferError : Buffer::BufferSuccess;
>  
>  	return buffer;
>  }
> -- 
> Regards,
> 
> Laurent Pinchart
> 
> _______________________________________________
> libcamera-devel mailing list
> libcamera-devel at lists.libcamera.org
> https://lists.libcamera.org/listinfo/libcamera-devel

-- 
Regards,
Niklas Söderlund