[libcamera-devel] [PATCH v1.1 2/4] libcamera: camera_manager: Use std::unique_ptr to store event dispatcher

[Laurent Pinchart]

Hi Jacopo,

On Fri, Jan 18, 2019 at 04:15:03PM +0100, Jacopo Mondi wrote:
> On Fri, Jan 18, 2019 at 02:32:01AM +0200, Laurent Pinchart wrote:
> > The CameraManager takes ownership of the dispatcher passed to the
> > setEventDispatcher() function. Enforces this by using std::unique_ptr<>.
> >
> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> > Changes since v1:
> >
> > - Use make_unique<> in CameraManager::setEventDispatcher()
> > ---
> >  include/libcamera/camera_manager.h |  4 ++--
> >  src/libcamera/camera_manager.cpp   | 12 +++++++-----
> >  2 files changed, 9 insertions(+), 7 deletions(-)
> >
> > diff --git a/include/libcamera/camera_manager.h b/include/libcamera/camera_manager.h
> > index 6cfcba3c3933..b82a8ce95b9f 100644
> > --- a/include/libcamera/camera_manager.h
> > +++ b/include/libcamera/camera_manager.h
> > @@ -29,7 +29,7 @@ public:
> >
> >  	static CameraManager *instance();
> >
> > -	void setEventDispatcher(EventDispatcher *dispatcher);
> > +	void setEventDispatcher(std::unique_ptr<EventDispatcher> dispatcher);
> >  	EventDispatcher *eventDispatcher();
> >
> >  private:
> > @@ -41,7 +41,7 @@ private:
> >  	std::unique_ptr<DeviceEnumerator> enumerator_;
> >  	std::vector<PipelineHandler *> pipes_;
> >
> > -	EventDispatcher *dispatcher_;
> > +	std::unique_ptr<EventDispatcher> dispatcher_;
> >  };
> >
> >  } /* namespace libcamera */
> > diff --git a/src/libcamera/camera_manager.cpp b/src/libcamera/camera_manager.cpp
> > index 9f554be57e33..1430bb0d75a5 100644
> > --- a/src/libcamera/camera_manager.cpp
> > +++ b/src/libcamera/camera_manager.cpp
> > @@ -12,6 +12,7 @@
> >  #include "event_dispatcher_poll.h"
> >  #include "log.h"
> >  #include "pipeline_handler.h"
> > +#include "utils.h"
> >
> >  /**
> >   * \file camera_manager.h
> > @@ -58,7 +59,6 @@ CameraManager::CameraManager()
> >
> >  CameraManager::~CameraManager()
> >  {
> > -	delete dispatcher_;
> >  }
> >
> >  /**
> > @@ -209,14 +209,14 @@ CameraManager *CameraManager::instance()
> >   * The CameraManager takes ownership of the event dispatcher and will delete it
> >   * when the application terminates.
> >   */
> > -void CameraManager::setEventDispatcher(EventDispatcher *dispatcher)
> > +void CameraManager::setEventDispatcher(std::unique_ptr<EventDispatcher> dispatcher)
> >  {
> >  	if (dispatcher_) {
> >  		LOG(Warning) << "Event dispatcher is already set";
> >  		return;
> >  	}
> >
> > -	dispatcher_ = dispatcher;
> > +	dispatcher_ = std::move(dispatcher);
> >  }
> >
> >  /**
> > @@ -226,14 +226,16 @@ void CameraManager::setEventDispatcher(EventDispatcher *dispatcher)
> >   * If no dispatcher has been set, a default poll-based implementation is created
> >   * and returned, and no custom event dispatcher may be installed anymore.
> >   *
> > + * The returned event dispatcher is valid until the camera manager is destroyed.
> > + *
> >   * \return Pointer to the event dispatcher
> >   */
> >  EventDispatcher *CameraManager::eventDispatcher()
> >  {
> >  	if (!dispatcher_)
> 
> Does this access the resources owned by the unique_ptr<> ?

If you mean does this check whether the pointer owned by the
std::unique_ptr<> dispatch_ is null, then yes, it does, through operator
bool:

https://en.cppreference.com/w/cpp/memory/unique_ptr/operator_bool

If you meant something else, then please rephrase the question :-)

> > -		dispatcher_ = new EventDispatcherPoll();
> > +		dispatcher_ = utils::make_unique<EventDispatcherPoll>();
> >
> > -	return dispatcher_;
> > +	return dispatcher_.get();
> >  }
> >
> >  } /* namespace libcamera */

-- 
Regards,

Laurent Pinchart