[libcamera-devel] [PATCH 02/10] libcamera: event_notifier: Add 'enable' constructor parameter

[Laurent Pinchart]

Hi Jacopo,

Thank you for the patch.

On Thu, Oct 28, 2021 at 01:15:12PM +0200, Jacopo Mondi wrote:
> Add an 'enable' parameter to the EventNotifier class constructor.
> 
> Currently an EvenNotifier is enabled as soon as it is constructed.

s/EvenNotifier/EventNotifier/

> Add an optional parameter to the class constructor to allow post-poning

s/post-poning/postponing/

> the notifier activation.

s/activation/enablement/ (as activation refers to the notifier reporting
an event).

> As the 'enable' parameter has a default value of true, existing users
> of the class should not be updated.

s/should not be updated/don't need to be updated/

> Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
> ---
>  include/libcamera/base/event_notifier.h |  2 +-
>  src/libcamera/base/event_notifier.cpp   | 12 ++++++++----
>  2 files changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/include/libcamera/base/event_notifier.h b/include/libcamera/base/event_notifier.h
> index f7722a32ef55..4d373a5290cc 100644
> --- a/include/libcamera/base/event_notifier.h
> +++ b/include/libcamera/base/event_notifier.h
> @@ -25,7 +25,7 @@ public:
>  		Exception,
>  	};
>  
> -	EventNotifier(int fd, Type type, Object *parent = nullptr);
> +	EventNotifier(int fd, Type type, Object *parent = nullptr, bool enable = true);
>  	virtual ~EventNotifier();
>  
>  	Type type() const { return type_; }
> diff --git a/src/libcamera/base/event_notifier.cpp b/src/libcamera/base/event_notifier.cpp
> index fd93c0878c6f..40428cf24a50 100644
> --- a/src/libcamera/base/event_notifier.cpp
> +++ b/src/libcamera/base/event_notifier.cpp
> @@ -26,8 +26,11 @@ namespace libcamera {
>   *
>   * The EventNotifier models a file descriptor event source that can be
>   * monitored. It is created with the file descriptor to be monitored and the
> - * type of event, and is enabled by default. It will emit the \ref activated
> - * signal whenever an event of the monitored type occurs on the file descriptor.
> + * type of event. It will emit the \ref activated signal whenever an event of
> + * the monitored type occurs on the file descriptor.
> + *
> + * An EventNotifier is enabled by default when created, unless otherwise
> + * specified through the optional 'enable' constructor parameter.

I'd squash this with the paragraph dealing with enablement:

 * The \a enable parameter controls whether the notifier is created enabled or
 * disabled. When the notifier is disabled it ignores events and does not emit
 * the \ref activated signal. The notifier can be manually enabled or disabled
 * with the setEnabled() function.

The patch looks OK to me, so

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

I don't know how it will be used though, so I may propose an alternative
when reviewing the rest of the series.

>   *
>   * Supported type of events are EventNotifier::Read, EventNotifier::Write and
>   * EventNotifier::Exception. The type is specified when constructing the
> @@ -62,11 +65,12 @@ namespace libcamera {
>   * \param[in] fd The file descriptor to monitor
>   * \param[in] type The event type to monitor
>   * \param[in] parent The parent Object
> + * \param[in] enable Notifier enable flag
>   */
> -EventNotifier::EventNotifier(int fd, Type type, Object *parent)
> +EventNotifier::EventNotifier(int fd, Type type, Object *parent, bool enable)
>  	: Object(parent), fd_(fd), type_(type), enabled_(false)
>  {
> -	setEnabled(true);
> +	setEnabled(enable);
>  }
>  
>  EventNotifier::~EventNotifier()

-- 
Regards,

Laurent Pinchart