[libcamera-devel] [PATCH v3 06/13] libcamera: stream: Add operator<<() to print StreamRole as a string

[Jacopo Mondi]

Hi Laurent

On Mon, Oct 24, 2022 at 03:03:49AM +0300, Laurent Pinchart via libcamera-devel wrote:
> libcamera prints stream role values in log messages. To be more
> user-friendly, add a specialization of operator<<() to print the role
> name as a string instead of a numerical value.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
>  include/libcamera/stream.h |  3 +++
>  src/libcamera/stream.cpp   | 19 +++++++++++++++++++
>  2 files changed, 22 insertions(+)
>
> diff --git a/include/libcamera/stream.h b/include/libcamera/stream.h
> index f0ae7e62e0a3..efec695ad317 100644
> --- a/include/libcamera/stream.h
> +++ b/include/libcamera/stream.h
> @@ -9,6 +9,7 @@
>
>  #include <map>
>  #include <memory>
> +#include <ostream>
>  #include <string>
>  #include <vector>
>
> @@ -70,6 +71,8 @@ enum StreamRole {
>
>  using StreamRoles = std::vector<StreamRole>;
>
> +std::ostream &operator<<(std::ostream &out, StreamRole role);
> +
>  class Stream
>  {
>  public:
> diff --git a/src/libcamera/stream.cpp b/src/libcamera/stream.cpp
> index 686e693bccba..67f308157fbf 100644
> --- a/src/libcamera/stream.cpp
> +++ b/src/libcamera/stream.cpp
> @@ -417,6 +417,25 @@ std::string StreamConfiguration::toString() const
>   * acceptable.
>   */
>
> +/**
> + * \brief Insert a text representation of a StreamRole into an output stream
> + * \param[in] out The output stream
> + * \param[in] role The StreamRole
> + * \return The output stream \a out
> + */
> +std::ostream &operator<<(std::ostream &out, StreamRole role)
> +{
> +	static constexpr std::array<const char *, 4> names{
> +		"Raw",
> +		"StillCapture",
> +		"VideoRecording",
> +		"Viewfinder",
> +	};

My only concern is about the enum and the list of names going out of
sync. A map might help ?

> +
> +	out << names[static_cast<std::underlying_type_t<StreamRole>>(role)];
> +	return out;
> +}
> +
>  /**
>   * \typedef StreamRoles
>   * \brief A vector of StreamRole
> --
> Regards,
>
> Laurent Pinchart
>