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

[Kieran Bingham]

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 ;-)


--
Kieran



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)) {
+		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,
-- 
2.25.1