[PATCH 4/4] apps: cam: Print control direction information

[Laurent Pinchart]

Hi Paul,

Thank you for the patch.

On Tue, Nov 26, 2024 at 12:30:03AM +0900, Paul Elder wrote:
> Now that there is support for retrieving the allowed directions of a
> control, print this information when listing controls.
> 
> Sample output:
> $ cam --list-controls -c 2
> Using camera Virtual0 as cam0
> Control: [io] draft::FaceDetectMode:
>   - FaceDetectModeOff (0)
> Control: [i ] libcamera::FrameDurationLimits: [16666..33333]

I was expecting [in], [out] or [input], but i/o has the advantage of
aligning the controls names. We could still achieve the same with

[in   ]
[  out]
[inout]

at the cost of longer lines, or

'[in]   '
'[out]  '
'[inout]'

any opinion from anyone ?

>    Size: 2
> 
> Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
> ---
>  src/apps/cam/camera_session.cpp | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/src/apps/cam/camera_session.cpp b/src/apps/cam/camera_session.cpp
> index 6e9890ccfda1..1baf36fcfd3c 100644
> --- a/src/apps/cam/camera_session.cpp
> +++ b/src/apps/cam/camera_session.cpp
> @@ -159,12 +159,18 @@ CameraSession::~CameraSession()
>  void CameraSession::listControls() const
>  {
>  	for (const auto &[id, info] : camera_->controls()) {
> +		std::stringstream io;
> +		io << "["
> +		   << (id->isInput() ? "i" : " ")
> +		   << (id->isOutput() ? "o" : " ")
> +		   << "] ";

I wonder if a stringstream is overkill here, maybe you could fold the
"[" and "]" in the statements below, and just construct a string here.
It also depends on the outcome of the above discussion. Up to you.

> +
>  		if (info.values().empty()) {
> -			std::cout << "Control: "
> +			std::cout << "Control: " << io.str()
>  				  << id->vendor() << "::" << id->name() << ": "
>  				  << info.toString() << std::endl;
>  		} else {
> -			std::cout << "Control: "
> +			std::cout << "Control: " << io.str()
>  				  << id->vendor() << "::" << id->name() << ":"
>  				  << std::endl;
>  			for (const auto &value : info.values()) {

-- 
Regards,

Laurent Pinchart