libcamera: pipeline: virtual: Fill buffer's metadata

Fill the `FrameMetadata` object of the `FrameBuffer`s because it
should not be left uninitialized as users expect to be able to
access it and find reasonable data there.

Bug: https://bugs.libcamera.org/show_bug.cgi?id=245
Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>

src/libcamera/pipeline/virtual/virtual.cpp

@@ -286,6 +286,11 @@ int PipelineHandlerVirtual::exportFrameBuffers([[maybe_unused]] Camera *camera,
 int PipelineHandlerVirtual::start([[maybe_unused]] Camera *camera,
 				  [[maybe_unused]] const ControlList *controls)
 {
+	VirtualCameraData *data = cameraData(camera);
+
+	for (auto &s : data->streamConfigs_)
+		s.seq = 0;
+
 	return 0;
 }
 
@@ -297,13 +302,24 @@ int PipelineHandlerVirtual::queueRequestDevice([[maybe_unused]] Camera *camera,
 					       Request *request)
 {
 	VirtualCameraData *data = cameraData(camera);
+	const auto timestamp = currentTimestamp();
 
 	for (auto const &[stream, buffer] : request->buffers()) {
 		bool found = false;
 		/* map buffer and fill test patterns */
 		for (auto &streamConfig : data->streamConfigs_) {
 			if (stream == &streamConfig.stream) {
+				FrameMetadata &fmd = buffer->_d()->metadata();
+
+				fmd.status = FrameMetadata::Status::FrameSuccess;
+				fmd.sequence = streamConfig.seq++;
+				fmd.timestamp = timestamp;
+
+				for (const auto [i, p] : utils::enumerate(buffer->planes()))
+					fmd.planes()[i].bytesused = p.length;
+
 				found = true;
+
 				if (streamConfig.frameGenerator->generateFrame(
 					    stream->configuration().size, buffer))
 					buffer->_d()->cancel();
@@ -315,7 +331,7 @@ int PipelineHandlerVirtual::queueRequestDevice([[maybe_unused]] Camera *camera,
 		ASSERT(found);
 	}
 
-	request->metadata().set(controls::SensorTimestamp, currentTimestamp());
+	request->metadata().set(controls::SensorTimestamp, timestamp);
 	completeRequest(request);
 
 	return 0;

src/libcamera/pipeline/virtual/virtual.h

@@ -37,6 +37,7 @@ public:
 	struct StreamConfig {
 		Stream stream;
 		std::unique_ptr<FrameGenerator> frameGenerator;
+		unsigned int seq = 0;
 	};
 	/* The config file is parsed to the Configuration struct */
 	struct Configuration {