[libcamera-devel] [RFC PATCH v2 3/5] android: camera_stream: Notify process() status with a Signal

[Umang Jain]

CameraStream takes care of any post-processing required via the
CameraStream::process(). Since the post-processor will be moved
to a separate thread (in subsequent commit), the caller of
CameraStream::process() should be able to get notified about the
status, in order to proceed further for completing the callbacks
to android framework.

Therefore, chain up to PostProcessor::processComplete signal in its
signal handler. Currently, we have only one post-processor in-use,
hence emit the corresponding CameraStream::PostProcessing value
according to the  PostProcessor::status received in the signal handler.

Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>
---
 src/android/camera_stream.cpp | 10 ++++++++++
 src/android/camera_stream.h   | 13 ++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/android/camera_stream.cpp b/src/android/camera_stream.cpp
index a3c65562..92dd745b 100644
--- a/src/android/camera_stream.cpp
+++ b/src/android/camera_stream.cpp
@@ -81,6 +81,8 @@ int CameraStream::configure()
 		int ret = postProcessor_->configure(configuration(), output);
 		if (ret)
 			return ret;
+
+		postProcessor_->processComplete.connect(this, &CameraStream::handlePostProcessing);
 	}
 
 	if (allocator_) {
@@ -121,6 +123,14 @@ int CameraStream::process(const libcamera::FrameBuffer *source,
 	return postProcessor_->process(source, &dest, requestMetadata, resultMetadata);
 }
 
+void CameraStream::handlePostProcessing(PostProcessor::Status status)
+{
+	if (status == PostProcessor::Status::Success)
+		processComplete.emit(ProcessStatus::Success);
+	else
+		processComplete.emit(ProcessStatus::Failed);
+}
+
 FrameBuffer *CameraStream::getBuffer()
 {
 	if (!allocator_)
diff --git a/src/android/camera_stream.h b/src/android/camera_stream.h
index 5c232cb6..f9b11e5d 100644
--- a/src/android/camera_stream.h
+++ b/src/android/camera_stream.h
@@ -13,15 +13,18 @@
 
 #include <hardware/camera3.h>
 
+#include <libcamera/base/signal.h>
+
 #include <libcamera/camera.h>
 #include <libcamera/framebuffer.h>
 #include <libcamera/framebuffer_allocator.h>
 #include <libcamera/geometry.h>
 #include <libcamera/pixel_format.h>
 
+#include "post_processor.h"
+
 class CameraDevice;
 class CameraMetadata;
-class PostProcessor;
 
 class CameraStream
 {
@@ -125,7 +128,15 @@ public:
 	libcamera::FrameBuffer *getBuffer();
 	void putBuffer(libcamera::FrameBuffer *buffer);
 
+	enum ProcessStatus {
+		Failed,
+		Success,
+	};
+	libcamera::Signal<ProcessStatus> processComplete;
+
 private:
+	void handlePostProcessing(PostProcessor::Status status);
+
 	CameraDevice *const cameraDevice_;
 	const libcamera::CameraConfiguration *config_;
 	const Type type_;
-- 
2.31.1