[libcamera-devel] [PATCH 4/5] libcamera: Add operator<<() for V4L2 format classes

[Kieran Bingham]

Quoting Laurent Pinchart via libcamera-devel (2022-04-29 22:23:47)
> Implement the stream output operator<<() for the V4L2DeviceFormat and
> V4L2SubdeviceFormat classes to simplify printing them.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>


Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>

> ---
>  include/libcamera/internal/v4l2_subdevice.h   |  3 ++
>  include/libcamera/internal/v4l2_videodevice.h |  3 ++
>  src/libcamera/v4l2_subdevice.cpp              | 34 +++++++++++++------
>  src/libcamera/v4l2_videodevice.cpp            | 16 ++++++++-
>  4 files changed, 45 insertions(+), 11 deletions(-)
> 
> diff --git a/include/libcamera/internal/v4l2_subdevice.h b/include/libcamera/internal/v4l2_subdevice.h
> index 58d1e5114e7b..6fda52ada41b 100644
> --- a/include/libcamera/internal/v4l2_subdevice.h
> +++ b/include/libcamera/internal/v4l2_subdevice.h
> @@ -9,6 +9,7 @@
>  
>  #include <memory>
>  #include <optional>
> +#include <ostream>
>  #include <string>
>  #include <vector>
>  
> @@ -35,6 +36,8 @@ struct V4L2SubdeviceFormat {
>         uint8_t bitsPerPixel() const;
>  };
>  
> +std::ostream &operator<<(std::ostream &out, const V4L2SubdeviceFormat &f);
> +
>  class V4L2Subdevice : public V4L2Device
>  {
>  public:
> diff --git a/include/libcamera/internal/v4l2_videodevice.h b/include/libcamera/internal/v4l2_videodevice.h
> index 9c9493cc16ed..23f37f83f8e2 100644
> --- a/include/libcamera/internal/v4l2_videodevice.h
> +++ b/include/libcamera/internal/v4l2_videodevice.h
> @@ -11,6 +11,7 @@
>  #include <atomic>
>  #include <memory>
>  #include <optional>
> +#include <ostream>
>  #include <stdint.h>
>  #include <string>
>  #include <vector>
> @@ -180,6 +181,8 @@ public:
>         const std::string toString() const;
>  };
>  
> +std::ostream &operator<<(std::ostream &out, const V4L2DeviceFormat &f);
> +
>  class V4L2VideoDevice : public V4L2Device
>  {
>  public:
> diff --git a/src/libcamera/v4l2_subdevice.cpp b/src/libcamera/v4l2_subdevice.cpp
> index d5ae460571d8..b3d0ddad83db 100644
> --- a/src/libcamera/v4l2_subdevice.cpp
> +++ b/src/libcamera/v4l2_subdevice.cpp
> @@ -190,17 +190,10 @@ const std::map<uint32_t, V4L2SubdeviceFormatInfo> formatInfoMap = {
>   */
>  const std::string V4L2SubdeviceFormat::toString() const
>  {
> -       std::stringstream mbus;
> -       mbus << size << "-";
> +       std::stringstream ss;
> +       ss << *this;
>  
> -       const auto it = formatInfoMap.find(mbus_code);
> -
> -       if (it == formatInfoMap.end())
> -               mbus << utils::hex(mbus_code, 4);
> -       else
> -               mbus << it->second.name;
> -
> -       return mbus.str();
> +       return ss.str();
>  }
>  
>  /**
> @@ -220,6 +213,27 @@ uint8_t V4L2SubdeviceFormat::bitsPerPixel() const
>         return it->second.bitsPerPixel;
>  }
>  
> +/**
> + * \brief Insert a text representation of a V4L2SubdeviceFormat into an output
> + * stream
> + * \param[in] out The output stream
> + * \param[in] f The V4L2SubdeviceFormat
> + * \return The output stream \a out
> + */
> +std::ostream &operator<<(std::ostream &out, const V4L2SubdeviceFormat &f)
> +{
> +       out << f.size << "-";
> +
> +       const auto it = formatInfoMap.find(f.mbus_code);
> +
> +       if (it == formatInfoMap.end())
> +               out << utils::hex(f.mbus_code, 4);
> +       else
> +               out << it->second.name;
> +
> +       return out;
> +}
> +
>  /**
>   * \class V4L2Subdevice
>   * \brief A V4L2 subdevice as exposed by the Linux kernel
> diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
> index 5ba866ad71bb..5b4637b1a39e 100644
> --- a/src/libcamera/v4l2_videodevice.cpp
> +++ b/src/libcamera/v4l2_videodevice.cpp
> @@ -433,10 +433,24 @@ bool V4L2BufferCache::Entry::operator==(const FrameBuffer &buffer) const
>  const std::string V4L2DeviceFormat::toString() const
>  {
>         std::stringstream ss;
> -       ss << size << "-" << fourcc.toString();
> +       ss << *this;
> +
>         return ss.str();
>  }
>  
> +/**
> + * \brief Insert a text representation of a V4L2DeviceFormat into an output
> + * stream
> + * \param[in] out The output stream
> + * \param[in] f The V4L2DeviceFormat
> + * \return The output stream \a out
> + */
> +std::ostream &operator<<(std::ostream &out, const V4L2DeviceFormat &f)
> +{
> +       out << f.size << "-" << f.fourcc;
> +       return out;
> +}
> +
>  /**
>   * \class V4L2VideoDevice
>   * \brief V4L2VideoDevice object and API
> -- 
> Regards,
> 
> Laurent Pinchart
>