[libcamera-devel] [PATCH v3] cam: Add --monitor option

[Laurent Pinchart]

Hi Kieran,

On Mon, Aug 03, 2020 at 02:13:52PM +0100, Kieran Bingham wrote:
> On 03/08/2020 14:09, Laurent Pinchart wrote:
> > On Mon, Aug 03, 2020 at 01:48:23PM +0100, Kieran Bingham wrote:
> >> From: Umang Jain <email at uajain.com>
> >>
> >> Add --monitor to monitor new hotplug and unplug camera events from
> >> the CameraManager.
> >>
> >> Signed-off-by: Umang Jain <email at uajain.com>
> >> Reviewed-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
> >> Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> >> ---
> >>  src/cam/main.cpp | 27 +++++++++++++++++++++++++++
> >>  src/cam/main.h   |  1 +
> >>  2 files changed, 28 insertions(+)
> >>
> >> v3:
> >>   - V1 rebased, and slightly modified to update the conditional
> >>     connection of the signals during CamApp::init()
> >>   - Adjust formatting of parser.addOption
> >>
> >>
> >> Hi all,
> >>
> >> I am aiming to merge Umang's patch, but because I have ended up making a
> >> more than superficial change to the code path in CamApp::init() I'm
> >> reposting as v3. This is essentially v1 of Umangs patch (thanks, and
> >> sorry for incorrectly leading you to make a v2) with the small line
> >> adjustment to the parser addition, but a more impacting adjustment to
> >> the conditional which enables the signals.
> >>
> >>
> >> If there are no objections, I can merge this patch.
> >>
> >> Testing with the two options combined shows:
> >>
> >> ./build/src/cam/cam -m -c 1 -C
> >>
> >> fps: 25.64 stream0 seq: 000052 bytesused: 36000
> >> fps: 25.00 stream0 seq: 000053 bytesused: 36024
> >> fps: 25.00 stream0 seq: 000054 bytesused: 36784
> >> fps: 25.64 stream0 seq: 000055 bytesused: 36968
> >> fps: 25.64 stream0 seq: 000056 bytesused: 36792
> >> fps: 25.00 stream0 seq: 000057 bytesused: 37040
> >> fps: 25.64 stream0 seq: 000058 bytesused: 36808
> >> fps: 25.00 stream0 seq: 000059 bytesused: 36848
> >> fps: 25.00 stream0 seq: 000060 bytesused: 37480
> >> Camera Removed: VF0520 Live! Cam Sync: VF0520 L
> >> Camera Added: VF0520 Live! Cam Sync: VF0520 L
> >> Camera Removed: VF0520 Live! Cam Sync: VF0520 L
> >>
> >> So the stream doesn't continue, but no crashing - so we're fine ;-)
> >>
> >> diff --git a/src/cam/main.cpp b/src/cam/main.cpp
> >> index f5aba041d7c4..3ceb6576960e 100644
> >> --- a/src/cam/main.cpp
> >> +++ b/src/cam/main.cpp
> >> @@ -36,6 +36,8 @@ public:
> >>  	void quit();
> >>  
> >>  private:
> >> +	void cameraAdded(std::shared_ptr<Camera> cam);
> >> +	void cameraRemoved(std::shared_ptr<Camera> cam);
> >>  	int parseOptions(int argc, char *argv[]);
> >>  	int prepareConfig();
> >>  	int listControls();
> >> @@ -123,6 +125,12 @@ int CamApp::init(int argc, char **argv)
> >>  			return ret;
> >>  	}
> >>  
> >> +	if (options_.isSet(OptMonitor)) {
> >> +		cm_->cameraAdded.connect(this, &CamApp::cameraAdded);
> >> +		cm_->cameraRemoved.connect(this, &CamApp::cameraRemoved);
> >> +		std::cout << "Monitoring new hotplug and unplug events..." << std::endl;
> >> +	}
> >> +
> >>  	loop_ = new EventLoop(cm_->eventDispatcher());
> >>  
> >>  	return 0;
> >> @@ -186,6 +194,9 @@ int CamApp::parseOptions(int argc, char *argv[])
> >>  			 "list-controls");
> >>  	parser.addOption(OptListProperties, OptionNone, "List cameras properties",
> >>  			 "list-properties");
> >> +	parser.addOption(OptMonitor, OptionNone,
> >> +			 "Monitor for hotplug and unplug camera events",
> >> +			 "monitor");
> >>  	parser.addOption(OptStrictFormats, OptionNone,
> >>  			 "Do not allow requested stream format(s) to be adjusted",
> >>  			 "strict-formats");
> >> @@ -309,6 +320,16 @@ int CamApp::infoConfiguration()
> >>  	return 0;
> >>  }
> >>  
> >> +void CamApp::cameraAdded(std::shared_ptr<Camera> cam)
> >> +{
> >> +	std::cout << "Camera Added: " << cam->name() << std::endl;
> >> +}
> >> +
> >> +void CamApp::cameraRemoved(std::shared_ptr<Camera> cam)
> >> +{
> >> +	std::cout << "Camera Removed: " << cam->name() << std::endl;
> >> +}
> >> +
> >>  int CamApp::run()
> >>  {
> >>  	int ret;
> >> @@ -346,6 +367,12 @@ int CamApp::run()
> >>  		return capture.run(options_);
> >>  	}
> >>  
> >> +	if (options_.isSet(OptMonitor)) {
> > 
> > I wonder if we should add here
> > 
> > 		std::cout << "Press Ctrl-C to interrupt" << std::endl;
> > 
> > With or without that (or with a modified version),
> 
> Well, I hope that is usually expected, but it does otherwise sit
> reasonably quietly:
> 
> The current output is:
> 
> > ./build/src/cam/cam -m
> > [5:07:13.071292781] [83575]  INFO IPAManager ipa_manager.cpp:136 libcamera is not installed. Adding '/home/libcamera/libcamera-next/build/src/ipa' to the IPA search path
> > [5:07:13.076546278] [83575]  INFO Camera camera_manager.cpp:287 libcamera v0.0.11+797-785d7418-dirty
> > [5:07:13.223619576] [83576]  INFO IPAProxy ipa_proxy.cpp:122 libcamera is not installed. Loading IPA configuration from '/home/libcamera/libcamera-next/src/ipa/vimc/data'
> > Monitoring new hotplug and unplug events...
> 
> I hope the '...' implies that it is waiting.
> 
> Would you still like to see the "Press Ctrl-C to interrupt" ?
> 
> I'm happy with that text if you think it helps, otherwise the loop does
> indeed sit there idly (excepting actual hotplug notifications of course).

If it was just me I'd remove the ... and add the Ctrl-C message, as when
specifying -C -m the ... seem a bit weird. Up to you really, I don't
mind. Pick the option you like best and push :-)

> > Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > 
> >> +		ret = loop_->exec();
> >> +		if (ret)
> >> +			std::cout << "Failed to run monitor loop" << std::endl;
> >> +	}
> >> +
> >>  	return 0;
> >>  }
> >>  
> >> diff --git a/src/cam/main.h b/src/cam/main.h
> >> index 6f95add31a63..ea8dfd330830 100644
> >> --- a/src/cam/main.h
> >> +++ b/src/cam/main.h
> >> @@ -15,6 +15,7 @@ enum {
> >>  	OptInfo = 'I',
> >>  	OptList = 'l',
> >>  	OptListProperties = 'p',
> >> +	OptMonitor = 'm',
> >>  	OptStream = 's',
> >>  	OptListControls = 256,
> >>  	OptStrictFormats = 257,

-- 
Regards,

Laurent Pinchart