[libcamera-devel] [PATCH v6 7/9] android: camera_device: Use the new CameraMetadata helper class

Laurent Pinchart laurent.pinchart at ideasonboard.com
Thu Sep 5 22:39:17 CEST 2019


Hi Jacopo,

On Thu, Sep 05, 2019 at 10:25:03PM +0200, Jacopo Mondi wrote:
> On Thu, Sep 05, 2019 at 01:02:59PM +0300, Laurent Pinchart wrote:
> > On Thu, Sep 05, 2019 at 11:52:05AM +0200, Jacopo Mondi wrote:
> >> On Thu, Sep 05, 2019 at 12:36:57PM +0300, Laurent Pinchart wrote:
> >>> On Thu, Sep 05, 2019 at 10:18:28AM +0200, Jacopo Mondi wrote:
> >>>> On Thu, Sep 05, 2019 at 09:47:34AM +0200, Jacopo Mondi wrote:
> >>>>> From: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> >>>>>
> >>>>> Simplify the implementation of metadata handling in the CameraDevice
> >>>>> class by using the new CameraMetadata helper class.
> >>>>>
> >>>>> Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> >>>>> ---
> >>>>>  src/android/camera_device.cpp | 507 +++++++++++++---------------------
> >>>>>  src/android/camera_device.h   |  15 +-
> >>>>>  2 files changed, 198 insertions(+), 324 deletions(-)
> >>>>>
> >>>>> diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
> >>>>> index 5f8d19b9ef3d..475fa2404421 100644
> >>>>> --- a/src/android/camera_device.cpp
> >>>>> +++ b/src/android/camera_device.cpp
> >>>>> @@ -7,10 +7,10 @@
> >>>>>
> >>>>>  #include "camera_device.h"
> >>>>>
> >>>>> -#include <system/camera_metadata.h>
> >>>>> -
> >>>>>  #include "log.h"
> >>>>> +#include "utils.h"
> >>>>>
> >>>>> +#include "camera_metadata.h"
> >>>>>  #include "thread_rpc.h"
> >>>>>
> >>>>>  using namespace libcamera;
> >>>>> @@ -59,12 +59,10 @@ CameraDevice::CameraDevice(unsigned int id, const std::shared_ptr<Camera> &camer
> >>>>>  CameraDevice::~CameraDevice()
> >>>>>  {
> >>>>>  	if (staticMetadata_)
> >>>>> -		free_camera_metadata(staticMetadata_);
> >>>>> -	staticMetadata_ = nullptr;
> >>>>> +		delete staticMetadata_;
> >>>>>
> >>>>>  	if (requestTemplate_)
> >>>>> -		free_camera_metadata(requestTemplate_);
> >>>>> -	requestTemplate_ = nullptr;
> >>>>> +		delete requestTemplate_;
> >>>>>  }
> >>>>>
> >>>>>  /*
> >>>>> @@ -117,10 +115,8 @@ void CameraDevice::setCallbacks(const camera3_callback_ops_t *callbacks)
> >>>>>   */
> >>>>>  camera_metadata_t *CameraDevice::getStaticMetadata()
> >>>>>  {
> >>>>> -	int ret;
> >>>>> -
> >>>>>  	if (staticMetadata_)
> >>>>> -		return staticMetadata_;
> >>>>> +		return staticMetadata_->get();
> >>>>>
> >>>>>  	/*
> >>>>>  	 * The here reported metadata are enough to implement a basic capture
> >>>>> @@ -132,16 +128,21 @@ camera_metadata_t *CameraDevice::getStaticMetadata()
> >>>>>  	 * \todo Keep this in sync with the actual number of entries.
> >>>>>  	 * Currently: 46 entries, 390 bytes
> >>>>>  	 */
> >>>>> -	staticMetadata_ = allocate_camera_metadata(50, 500);
> >>>>> +	staticMetadata_ = new CameraMetadata(50, 500);
> >>>>> +	if (!staticMetadata_->isValid()) {
> >>>>> +		LOG(HAL, Error) << "Failed to allocate static metadata";
> >>>>> +		delete staticMetadata_;
> >>>>> +		staticMetadata_ = nullptr;
> >>>>> +		return nullptr;
> >>>>
> >>>> Empty line before return?
> >>>
> >>> I don't mind either way, but I haven't added one as the delete,
> >>> assignment to nullptr and return nullptr are logically grouped in my
> >>> opinion. Feel free to add a blank line if you prefer.
> >>
> >> Ok, if this was intentional let's keep it the way it is.
> >>
> >>>>> +	}
> >>>>>
> >>>>>  	/* Color correction static metadata. */
> >>>>>  	std::vector<uint8_t> aberrationModes = {
> >>>>>  		ANDROID_COLOR_CORRECTION_ABERRATION_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_COLOR_CORRECTION_AVAILABLE_ABERRATION_MODES,
> >>>>> -			aberrationModes.data(), aberrationModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_COLOR_CORRECTION_AVAILABLE_ABERRATION_MODES,
> >>>>> +				  aberrationModes.data(),
> >>>>> +				  aberrationModes.size());
> >>>>>
> >>>>>  	/* Control static metadata. */
> >>>>>  	std::vector<uint8_t> aeAvailableAntiBandingModes = {
> >>>>> @@ -150,294 +151,228 @@ camera_metadata_t *CameraDevice::getStaticMetadata()
> >>>>>  		ANDROID_CONTROL_AE_ANTIBANDING_MODE_60HZ,
> >>>>>  		ANDROID_CONTROL_AE_ANTIBANDING_MODE_AUTO,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AE_AVAILABLE_ANTIBANDING_MODES,
> >>>>> -			aeAvailableAntiBandingModes.data(),
> >>>>> -			aeAvailableAntiBandingModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AE_AVAILABLE_ANTIBANDING_MODES,
> >>>>> +				  aeAvailableAntiBandingModes.data(),
> >>>>> +				  aeAvailableAntiBandingModes.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> aeAvailableModes = {
> >>>>>  		ANDROID_CONTROL_AE_MODE_ON,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AE_AVAILABLE_MODES,
> >>>>> -			aeAvailableModes.data(), aeAvailableModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AE_AVAILABLE_MODES,
> >>>>> +				  aeAvailableModes.data(),
> >>>>> +				  aeAvailableModes.size());
> >>>>>
> >>>>>  	std::vector<int32_t> availableAeFpsTarget = {
> >>>>>  		15, 30,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES,
> >>>>> -			availableAeFpsTarget.data(),
> >>>>> -			availableAeFpsTarget.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES,
> >>>>> +				  availableAeFpsTarget.data(),
> >>>>> +				  availableAeFpsTarget.size());
> >>>>>
> >>>>>  	std::vector<int32_t> aeCompensationRange = {
> >>>>>  		0, 0,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AE_COMPENSATION_RANGE,
> >>>>> -			aeCompensationRange.data(),
> >>>>> -			aeCompensationRange.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AE_COMPENSATION_RANGE,
> >>>>> +				  aeCompensationRange.data(),
> >>>>> +				  aeCompensationRange.size());
> >>>>>
> >>>>>  	const camera_metadata_rational_t aeCompensationStep[] = {
> >>>>>  		{ 0, 1 }
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AE_COMPENSATION_STEP,
> >>>>> -			aeCompensationStep, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AE_COMPENSATION_STEP,
> >>>>> +				  aeCompensationStep, 1);
> >>>>>
> >>>>>  	std::vector<uint8_t> availableAfModes = {
> >>>>>  		ANDROID_CONTROL_AF_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AF_AVAILABLE_MODES,
> >>>>> -			availableAfModes.data(), availableAfModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AF_AVAILABLE_MODES,
> >>>>> +				  availableAfModes.data(),
> >>>>> +				  availableAfModes.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> availableEffects = {
> >>>>>  		ANDROID_CONTROL_EFFECT_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AVAILABLE_EFFECTS,
> >>>>> -			availableEffects.data(), availableEffects.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AVAILABLE_EFFECTS,
> >>>>> +				  availableEffects.data(),
> >>>>> +				  availableEffects.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> availableSceneModes = {
> >>>>>  		ANDROID_CONTROL_SCENE_MODE_DISABLED,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AVAILABLE_SCENE_MODES,
> >>>>> -			availableSceneModes.data(), availableSceneModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AVAILABLE_SCENE_MODES,
> >>>>> +				  availableSceneModes.data(),
> >>>>> +				  availableSceneModes.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> availableStabilizationModes = {
> >>>>>  		ANDROID_CONTROL_VIDEO_STABILIZATION_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AVAILABLE_VIDEO_STABILIZATION_MODES,
> >>>>> -			availableStabilizationModes.data(),
> >>>>> -			availableStabilizationModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AVAILABLE_VIDEO_STABILIZATION_MODES,
> >>>>> +				  availableStabilizationModes.data(),
> >>>>> +				  availableStabilizationModes.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> availableAwbModes = {
> >>>>>  		ANDROID_CONTROL_AWB_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AWB_AVAILABLE_MODES,
> >>>>> -			availableAwbModes.data(), availableAwbModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AWB_AVAILABLE_MODES,
> >>>>> +				  availableAwbModes.data(),
> >>>>> +				  availableAwbModes.size());
> >>>>>
> >>>>>  	std::vector<int32_t> availableMaxRegions = {
> >>>>>  		0, 0, 0,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_MAX_REGIONS,
> >>>>> -			availableMaxRegions.data(), availableMaxRegions.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_MAX_REGIONS,
> >>>>> +				  availableMaxRegions.data(),
> >>>>> +				  availableMaxRegions.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> sceneModesOverride = {
> >>>>>  		ANDROID_CONTROL_AE_MODE_ON,
> >>>>>  		ANDROID_CONTROL_AWB_MODE_AUTO,
> >>>>>  		ANDROID_CONTROL_AF_MODE_AUTO,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_SCENE_MODE_OVERRIDES,
> >>>>> -			sceneModesOverride.data(), sceneModesOverride.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_SCENE_MODE_OVERRIDES,
> >>>>> +				  sceneModesOverride.data(),
> >>>>> +				  sceneModesOverride.size());
> >>>>>
> >>>>>  	uint8_t aeLockAvailable = ANDROID_CONTROL_AE_LOCK_AVAILABLE_FALSE;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AE_LOCK_AVAILABLE,
> >>>>> -			&aeLockAvailable, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AE_LOCK_AVAILABLE,
> >>>>> +				  &aeLockAvailable, 1);
> >>>>>
> >>>>>  	uint8_t awbLockAvailable = ANDROID_CONTROL_AWB_LOCK_AVAILABLE_FALSE;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AWB_LOCK_AVAILABLE,
> >>>>> -			&awbLockAvailable, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AWB_LOCK_AVAILABLE,
> >>>>> +				  &awbLockAvailable, 1);
> >>>>>
> >>>>>  	char availableControlModes = ANDROID_CONTROL_MODE_AUTO;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_CONTROL_AVAILABLE_MODES,
> >>>>> -			&availableControlModes, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_CONTROL_AVAILABLE_MODES,
> >>>>> +				  &availableControlModes, 1);
> >>>>>
> >>>>>  	/* JPEG static metadata. */
> >>>>>  	std::vector<int32_t> availableThumbnailSizes = {
> >>>>>  		0, 0,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES,
> >>>>> -			availableThumbnailSizes.data(),
> >>>>> -			availableThumbnailSizes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES,
> >>>>> +				  availableThumbnailSizes.data(),
> >>>>> +				  availableThumbnailSizes.size());
> >>>>>
> >>>>>  	/* Sensor static metadata. */
> >>>>>  	int32_t pixelArraySize[] = {
> >>>>>  		2592, 1944,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_INFO_PIXEL_ARRAY_SIZE,
> >>>>> -				&pixelArraySize, 2);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_PIXEL_ARRAY_SIZE,
> >>>>> +				  &pixelArraySize, 2);
> >>>>>
> >>>>>  	int32_t sensorSizes[] = {
> >>>>>  		0, 0, 2560, 1920,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE,
> >>>>> -				&sensorSizes, 4);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE,
> >>>>> +				  &sensorSizes, 4);
> >>>>>
> >>>>>  	int32_t sensitivityRange[] = {
> >>>>>  		32, 2400,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_INFO_SENSITIVITY_RANGE,
> >>>>> -				&sensitivityRange, 2);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_SENSITIVITY_RANGE,
> >>>>> +				  &sensitivityRange, 2);
> >>>>>
> >>>>>  	uint16_t filterArr = ANDROID_SENSOR_INFO_COLOR_FILTER_ARRANGEMENT_GRBG;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_INFO_COLOR_FILTER_ARRANGEMENT,
> >>>>> -				&filterArr, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_COLOR_FILTER_ARRANGEMENT,
> >>>>> +				  &filterArr, 1);
> >>>>>
> >>>>>  	int64_t exposureTimeRange[] = {
> >>>>>  		100000, 200000000,
> >>>>>  	};
> >>>>
> >>>> I've been thinking for a while to stabilize on the use of std::vector in
> >>>> place of arrays, so e can always use .data() and .size() and have
> >>>> guaranteed we should only change the declaration and not the
> >>>> parameters to the addEntry() operation.
> >>>>
> >>>> This might be a good time to do so. What do you think?
> >>>
> >>> I've thought about it, and constructing a vector is a bit costly
> >>> compared to arrays. I'd rather used std::array<>, but that requires
> >>> specifying the size explicitly :-S I've been thinking about overloading
> >>> the addEntry() method, in order to be able to write
> >>>
> >>> 	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_EXPOSURE_TIME_RANGE,
> >>> 				  { 100000, 200000000 });
> >>>
> >>> I'm not sure if that will be possible as we need to handle different
> >>> data types, but I think it's worth a try. Other overloaded methods
> >>> should also be added for the arrays of a single element:
> >>>
> >>> 	staticMetadata_->addEntry(ANDROID_SENSOR_ORIENTATION, 0);
> >>>
> >>> I would prefer handling the standardisation of vector vs. array in a
> >>> separate patch, when dealing with overloaded versions of addEntry(), as
> >>> this patch is big enough already.
> >>
> >> Agreed
> >>
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_INFO_EXPOSURE_TIME_RANGE,
> >>>>> -				&exposureTimeRange, 2);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_EXPOSURE_TIME_RANGE,
> >>>>> +				  &exposureTimeRange, 2);
> >>>>>
> >>>>>  	int32_t orientation = 0;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_ORIENTATION,
> >>>>> -				&orientation, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_ORIENTATION,
> >>>>> +				  &orientation, 1);
> >>>>
> >>>> Fits in 1 line
> >>>
> >>> I've kept it on two lines to use similar constructs through the whole
> >>> function, but I don't mind much, so please feel free to change it if you
> >>> prefer.
> >>
> >> If it was intentional, let's keep it the way it is
> >>
> >>>>>
> >>>>>  	std::vector<int32_t> testPatterModes = {
> >>>>>  		ANDROID_SENSOR_TEST_PATTERN_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_AVAILABLE_TEST_PATTERN_MODES,
> >>>>> -				testPatterModes.data(), testPatterModes.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_AVAILABLE_TEST_PATTERN_MODES,
> >>>>> +				  testPatterModes.data(),
> >>>>> +				  testPatterModes.size());
> >>>>>
> >>>>>  	std::vector<float> physicalSize = {
> >>>>>  		2592, 1944,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_SENSOR_INFO_PHYSICAL_SIZE,
> >>>>> -				physicalSize.data(), physicalSize.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_PHYSICAL_SIZE,
> >>>>> +				  physicalSize.data(),
> >>>>> +				  physicalSize.size());
> >>>>
> >>>> Fits in 1 line
> >>>>
> >>>>>
> >>>>>  	uint8_t timestampSource = ANDROID_SENSOR_INFO_TIMESTAMP_SOURCE_UNKNOWN;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SENSOR_INFO_TIMESTAMP_SOURCE,
> >>>>> -			&timestampSource, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SENSOR_INFO_TIMESTAMP_SOURCE,
> >>>>> +				  &timestampSource, 1);
> >>>>>
> >>>>>  	/* Statistics static metadata. */
> >>>>>  	uint8_t faceDetectMode = ANDROID_STATISTICS_FACE_DETECT_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES,
> >>>>> -			&faceDetectMode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES,
> >>>>> +				  &faceDetectMode, 1);
> >>>>>
> >>>>>  	int32_t maxFaceCount = 0;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_STATISTICS_INFO_MAX_FACE_COUNT,
> >>>>> -			&maxFaceCount, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_STATISTICS_INFO_MAX_FACE_COUNT,
> >>>>> +				  &maxFaceCount, 1);
> >>>>>
> >>>>>  	/* Sync static metadata. */
> >>>>>  	int32_t maxLatency = ANDROID_SYNC_MAX_LATENCY_UNKNOWN;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SYNC_MAX_LATENCY, &maxLatency, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SYNC_MAX_LATENCY, &maxLatency, 1);
> >>>>>
> >>>>>  	/* Flash static metadata. */
> >>>>>  	char flashAvailable = ANDROID_FLASH_INFO_AVAILABLE_FALSE;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_FLASH_INFO_AVAILABLE,
> >>>>> -			&flashAvailable, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_FLASH_INFO_AVAILABLE,
> >>>>> +				  &flashAvailable, 1);
> >>>>>
> >>>>>  	/* Lens static metadata. */
> >>>>>  	std::vector<float> lensApertures = {
> >>>>>  		2.53 / 100,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_LENS_INFO_AVAILABLE_APERTURES,
> >>>>> -				lensApertures.data(), lensApertures.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_LENS_INFO_AVAILABLE_APERTURES,
> >>>>> +				  lensApertures.data(),
> >>>>> +				  lensApertures.size());
> >>>>>
> >>>>>  	uint8_t lensFacing = ANDROID_LENS_FACING_FRONT;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_LENS_FACING, &lensFacing, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_LENS_FACING, &lensFacing, 1);
> >>>>>
> >>>>>  	std::vector<float> lensFocalLenghts = {
> >>>>>  		1,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_LENS_INFO_AVAILABLE_FOCAL_LENGTHS,
> >>>>> -				lensFocalLenghts.data(),
> >>>>> -				lensFocalLenghts.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_LENS_INFO_AVAILABLE_FOCAL_LENGTHS,
> >>>>> +				  lensFocalLenghts.data(),
> >>>>> +				  lensFocalLenghts.size());
> >>>>>
> >>>>>  	std::vector<uint8_t> opticalStabilizations = {
> >>>>>  		ANDROID_LENS_OPTICAL_STABILIZATION_MODE_OFF,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION,
> >>>>> -				opticalStabilizations.data(),
> >>>>> -				opticalStabilizations.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION,
> >>>>> +				  opticalStabilizations.data(),
> >>>>> +				  opticalStabilizations.size());
> >>>>>
> >>>>>  	float hypeFocalDistance = 0;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_LENS_INFO_HYPERFOCAL_DISTANCE,
> >>>>> -				&hypeFocalDistance, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_LENS_INFO_HYPERFOCAL_DISTANCE,
> >>>>> +				  &hypeFocalDistance, 1);
> >>>>>
> >>>>>  	float minFocusDistance = 0;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_LENS_INFO_MINIMUM_FOCUS_DISTANCE,
> >>>>> -				&minFocusDistance, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_LENS_INFO_MINIMUM_FOCUS_DISTANCE,
> >>>>> +				  &minFocusDistance, 1);
> >>>>>
> >>>>>  	/* Noise reduction modes. */
> >>>>>  	uint8_t noiseReductionModes = ANDROID_NOISE_REDUCTION_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -				ANDROID_NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES,
> >>>>> -				&noiseReductionModes, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES,
> >>>>> +				  &noiseReductionModes, 1);
> >>>>>
> >>>>>  	/* Scaler static metadata. */
> >>>>>  	float maxDigitalZoom = 1;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SCALER_AVAILABLE_MAX_DIGITAL_ZOOM,
> >>>>> -			&maxDigitalZoom, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SCALER_AVAILABLE_MAX_DIGITAL_ZOOM,
> >>>>> +				  &maxDigitalZoom, 1);
> >>>>>
> >>>>>  	std::vector<uint32_t> availableStreamFormats = {
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_BLOB,
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_YCbCr_420_888,
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_IMPLEMENTATION_DEFINED,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SCALER_AVAILABLE_FORMATS,
> >>>>> -			availableStreamFormats.data(),
> >>>>> -			availableStreamFormats.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SCALER_AVAILABLE_FORMATS,
> >>>>> +				  availableStreamFormats.data(),
> >>>>> +				  availableStreamFormats.size());
> >>>>>
> >>>>>  	std::vector<uint32_t> availableStreamConfigurations = {
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_BLOB, 2560, 1920,
> >>>>> @@ -447,65 +382,57 @@ camera_metadata_t *CameraDevice::getStaticMetadata()
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_IMPLEMENTATION_DEFINED, 2560, 1920,
> >>>>>  		ANDROID_SCALER_AVAILABLE_STREAM_CONFIGURATIONS_OUTPUT,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SCALER_AVAILABLE_STREAM_CONFIGURATIONS,
> >>>>> -			availableStreamConfigurations.data(),
> >>>>> -			availableStreamConfigurations.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SCALER_AVAILABLE_STREAM_CONFIGURATIONS,
> >>>>> +				  availableStreamConfigurations.data(),
> >>>>> +				  availableStreamConfigurations.size());
> >>>>>
> >>>>>  	std::vector<int64_t> availableStallDurations = {
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_BLOB, 2560, 1920, 33333333,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SCALER_AVAILABLE_STALL_DURATIONS,
> >>>>> -			availableStallDurations.data(),
> >>>>> -			availableStallDurations.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SCALER_AVAILABLE_STALL_DURATIONS,
> >>>>> +				  availableStallDurations.data(),
> >>>>> +				  availableStallDurations.size());
> >>>>>
> >>>>>  	std::vector<int64_t> minFrameDurations = {
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_BLOB, 2560, 1920, 33333333,
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_IMPLEMENTATION_DEFINED, 2560, 1920, 33333333,
> >>>>>  		ANDROID_SCALER_AVAILABLE_FORMATS_YCbCr_420_888, 2560, 1920, 33333333,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SCALER_AVAILABLE_MIN_FRAME_DURATIONS,
> >>>>> -			minFrameDurations.data(), minFrameDurations.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SCALER_AVAILABLE_MIN_FRAME_DURATIONS,
> >>>>> +				  minFrameDurations.data(),
> >>>>> +				  minFrameDurations.size());
> >>>>>
> >>>>>  	uint8_t croppingType = ANDROID_SCALER_CROPPING_TYPE_CENTER_ONLY;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_SCALER_CROPPING_TYPE, &croppingType, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_SCALER_CROPPING_TYPE, &croppingType, 1);
> >>>>>
> >>>>>  	/* Info static metadata. */
> >>>>>  	uint8_t supportedHWLevel = ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL,
> >>>>> -			&supportedHWLevel, 1);
> >>>>> +	staticMetadata_->addEntry(ANDROID_INFO_SUPPORTED_HARDWARE_LEVEL,
> >>>>> +				  &supportedHWLevel, 1);
> >>>>>
> >>>>>  	/* Request static metadata. */
> >>>>>  	int32_t partialResultCount = 1;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_REQUEST_PARTIAL_RESULT_COUNT,
> >>>>> -			&partialResultCount, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_REQUEST_PARTIAL_RESULT_COUNT,
> >>>>> +				  &partialResultCount, 1);
> >>>>>
> >>>>>  	uint8_t maxPipelineDepth = 2;
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_REQUEST_PIPELINE_MAX_DEPTH,
> >>>>> -			&maxPipelineDepth, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_REQUEST_PIPELINE_MAX_DEPTH,
> >>>>> +				  &maxPipelineDepth, 1);
> >>>>>
> >>>>>  	std::vector<uint8_t> availableCapabilities = {
> >>>>>  		ANDROID_REQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(staticMetadata_,
> >>>>> -			ANDROID_REQUEST_AVAILABLE_CAPABILITIES,
> >>>>> -			availableCapabilities.data(),
> >>>>> -			availableCapabilities.size());
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	staticMetadata_->addEntry(ANDROID_REQUEST_AVAILABLE_CAPABILITIES,
> >>>>> +				  availableCapabilities.data(),
> >>>>> +				  availableCapabilities.size());
> >>>>> +
> >>>>> +	if (!staticMetadata_->isValid()) {
> >>>>> +		delete staticMetadata_;
> >>>>> +		staticMetadata_ = nullptr;
> >>>>> +		return nullptr;
> >>>>> +	}
> >>>>>
> >>>>> -	return staticMetadata_;
> >>>>> +	return staticMetadata_->get();
> >>>>>  }
> >>>>>
> >>>>>  /*
> >>>>> @@ -513,8 +440,6 @@ camera_metadata_t *CameraDevice::getStaticMetadata()
> >>>>>   */
> >>>>>  const camera_metadata_t *CameraDevice::constructDefaultRequestSettings(int type)
> >>>>>  {
> >>>>> -	int ret;
> >>>>> -
> >>>>>  	/*
> >>>>>  	 * \todo Inspect type and pick the right metadata pack.
> >>>>>  	 * As of now just use a single one for all templates.
> >>>>> @@ -545,89 +470,73 @@ const camera_metadata_t *CameraDevice::constructDefaultRequestSettings(int type)
> >>>>>  	}
> >>>>>
> >>>>>  	if (requestTemplate_)
> >>>>> -		return requestTemplate_;
> >>>>> +		return requestTemplate_->get();
> >>>>>
> >>>>>  	/*
> >>>>>  	 * \todo Keep this in sync with the actual number of entries.
> >>>>>  	 * Currently: 12 entries, 15 bytes
> >>>>>  	 */
> >>>>> -	requestTemplate_ = allocate_camera_metadata(15, 20);
> >>>>> +	requestTemplate_ = new CameraMetadata(15, 20);
> >>>>>  	if (!requestTemplate_) {
> >>>>>  		LOG(HAL, Error) << "Failed to allocate template metadata";
> >>>>> +		delete requestTemplate_;
> >>>>> +		requestTemplate_ = nullptr;
> >>>>
> >>>> Empty line before return ?
> >>>>
> >>>>>  		return nullptr;
> >>>>>  	}
> >>>>>
> >>>>>  	uint8_t aeMode = ANDROID_CONTROL_AE_MODE_ON;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AE_MODE,
> >>>>> -			&aeMode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AE_MODE,
> >>>>> +				   &aeMode, 1);
> >>>>
> >>>> This and many others entries here and below fit in 1 line.
> >>>>
> >>>>>
> >>>>>  	int32_t aeExposureCompensation = 0;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION,
> >>>>> -			&aeExposureCompensation, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AE_EXPOSURE_COMPENSATION,
> >>>>> +				   &aeExposureCompensation, 1);
> >>>>>
> >>>>>  	uint8_t aePrecaptureTrigger = ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER_IDLE;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER,
> >>>>> -			&aePrecaptureTrigger, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AE_PRECAPTURE_TRIGGER,
> >>>>> +				   &aePrecaptureTrigger, 1);
> >>>>>
> >>>>>  	uint8_t aeLock = ANDROID_CONTROL_AE_LOCK_OFF;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AE_LOCK,
> >>>>> -			&aeLock, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AE_LOCK,
> >>>>> +				   &aeLock, 1);
> >>>>>
> >>>>>  	uint8_t afTrigger = ANDROID_CONTROL_AF_TRIGGER_IDLE;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AF_TRIGGER,
> >>>>> -			&afTrigger, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AF_TRIGGER,
> >>>>> +				   &afTrigger, 1);
> >>>>>
> >>>>>  	uint8_t awbMode = ANDROID_CONTROL_AWB_MODE_AUTO;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AWB_MODE,
> >>>>> -			&awbMode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AWB_MODE,
> >>>>> +				   &awbMode, 1);
> >>>>>
> >>>>>  	uint8_t awbLock = ANDROID_CONTROL_AWB_LOCK_OFF;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_AWB_LOCK,
> >>>>> -			&awbLock, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_AWB_LOCK,
> >>>>> +				   &awbLock, 1);
> >>>>>
> >>>>>  	uint8_t flashMode = ANDROID_FLASH_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_FLASH_MODE,
> >>>>> -			&flashMode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_FLASH_MODE,
> >>>>> +				   &flashMode, 1);
> >>>>>
> >>>>>  	uint8_t faceDetectMode = ANDROID_STATISTICS_FACE_DETECT_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_STATISTICS_FACE_DETECT_MODE,
> >>>>> -			&faceDetectMode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_STATISTICS_FACE_DETECT_MODE,
> >>>>> +				   &faceDetectMode, 1);
> >>>>>
> >>>>>  	uint8_t noiseReduction = ANDROID_NOISE_REDUCTION_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_NOISE_REDUCTION_MODE, &noiseReduction, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_NOISE_REDUCTION_MODE,
> >>>>> +				   &noiseReduction, 1);
> >>>>>
> >>>>>  	uint8_t aberrationMode = ANDROID_COLOR_CORRECTION_ABERRATION_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_COLOR_CORRECTION_ABERRATION_MODE,
> >>>>> -			&aberrationMode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	requestTemplate_->addEntry(ANDROID_COLOR_CORRECTION_ABERRATION_MODE,
> >>>>> +				   &aberrationMode, 1);
> >>>>> +
> >>>>> +	requestTemplate_->addEntry(ANDROID_CONTROL_CAPTURE_INTENT,
> >>>>> +				   &captureIntent, 1);
> >>>>>
> >>>>> -	ret = add_camera_metadata_entry(requestTemplate_,
> >>>>> -			ANDROID_CONTROL_CAPTURE_INTENT,
> >>>>> -			&captureIntent, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	if (!requestTemplate_->isValid()) {
> >>>>> +		delete requestTemplate_;
> >>>>> +		requestTemplate_ = nullptr;
> >>>>
> >>>> You should return nullptr here, otherwise the below requestTemplate_->get();
> >>>> will de-reference a nullptr.
> >>>
> >>> Absolutely, my bad.
> >>>
> >>>>> +	}
> >>>>>
> >>>>> -	return requestTemplate_;
> >>>>> +	return requestTemplate_->get();
> >>>>>  }
> >>>>>
> >>>>>  /*
> >>>>> @@ -799,7 +708,7 @@ void CameraDevice::requestComplete(Request *request,
> >>>>>  {
> >>>>>  	Buffer *libcameraBuffer = buffers.begin()->second;
> >>>>>  	camera3_buffer_status status = CAMERA3_BUFFER_STATUS_OK;
> >>>>> -	camera_metadata_t *resultMetadata = nullptr;
> >>>>> +	std::unique_ptr<CameraMetadata> resultMetadata;
> >>>>>
> >>>>>  	if (request->status() != Request::RequestComplete) {
> >>>>>  		LOG(HAL, Error) << "Request not succesfully completed: "
> >>>>> @@ -837,16 +746,12 @@ void CameraDevice::requestComplete(Request *request,
> >>>>>  		captureResult.partial_result = 1;
> >>>>>  		resultMetadata = getResultMetadata(descriptor->frameNumber,
> >>>>>  						   libcameraBuffer->timestamp());
> >>>>> -		captureResult.result = resultMetadata;
> >>>>> +		captureResult.result = resultMetadata->get();
> >>>>>  	}
> >>>>>
> >>>>>  	callbacks_->process_capture_result(callbacks_, &captureResult);
> >>>>>
> >>>>>  	delete descriptor;
> >>>>> -	if (resultMetadata)
> >>>>> -		free_camera_metadata(resultMetadata);
> >>>>> -
> >>>>> -	return;
> >>>>>  }
> >>>>>
> >>>>>  void CameraDevice::notifyShutter(uint32_t frameNumber, uint64_t timestamp)
> >>>>> @@ -875,89 +780,63 @@ void CameraDevice::notifyError(uint32_t frameNumber, camera3_stream_t *stream)
> >>>>>  /*
> >>>>>   * Produce a set of fixed result metadata.
> >>>>>   */
> >>>>> -camera_metadata_t *CameraDevice::getResultMetadata(int frame_number,
> >>>>> -						   int64_t timestamp)
> >>>>> +std::unique_ptr<CameraMetadata> CameraDevice::getResultMetadata(int frame_number,
> >>>>
> >>>> Not a fan of smart pointers, you know already. How does this work?
> >>>> Because the compiler applies copy-elision or because of the move
> >>>> semantic applied on the return value?
> >>>
> >>> std::unique_ptr<> has an operator= that takes an rvalue reference to
> >>> another std::unique_ptr<>, and uses move semantic. As explained in
> >>> https://en.cppreference.com/w/cpp/language/value_category, an rvalue is
> >>> either a prvalue or an xvalue, and a prvalue can be "a function call or
> >>> an overloaded operator expression, whose return type is non-reference".
> >>> As far as I can tell, that's why we don't need an std::move() in the
> >>> caller.
> >>
> >> I see.. This seems to suggest both RVO and move semantic can play a
> >> role https://stackoverflow.com/a/46571941
> >>
> >> Ah, c++
> >>
> >>>> difficult to follow in my opinion.
> >>>
> >>> I think we should standardise as much as possible on std::unique_ptr<>
> >>> when passing ownership of a returned pointer. That's documented in
> >>> Documentation/coding-style.rst.
> >>
> >> Ack, let's keep it the way it is then.
> >>
> >>>>> +								int64_t timestamp)
> >>>>>  {
> >>>>> -	int ret;
> >>>>> -
> >>>>>  	/*
> >>>>>  	 * \todo Keep this in sync with the actual number of entries.
> >>>>>  	 * Currently: 13 entries, 36 bytes
> >>>>>  	 */
> >>>>> -	camera_metadata_t *resultMetadata = allocate_camera_metadata(15, 50);
> >>>>> +	std::unique_ptr<CameraMetadata> resultMetadata =
> >>>>> +		utils::make_unique<CameraMetadata>(15, 50);
> >>>>> +	if (!resultMetadata->isValid()) {
> >>>>> +		LOG(HAL, Error) << "Failed to allocate static metadata";
> >>>>> +		return nullptr;
> >>>>> +	}
> >>>>>
> >>>>>  	const uint8_t ae_state = ANDROID_CONTROL_AE_STATE_CONVERGED;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata, ANDROID_CONTROL_AE_STATE,
> >>>>> -					&ae_state, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_CONTROL_AE_STATE, &ae_state, 1);
> >>>>>
> >>>>>  	const uint8_t ae_lock = ANDROID_CONTROL_AE_LOCK_OFF;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata, ANDROID_CONTROL_AE_LOCK,
> >>>>> -					&ae_lock, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_CONTROL_AE_LOCK, &ae_lock, 1);
> >>>>>
> >>>>>  	uint8_t af_state = ANDROID_CONTROL_AF_STATE_INACTIVE;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata, ANDROID_CONTROL_AF_STATE,
> >>>>> -					&af_state, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_CONTROL_AF_STATE, &af_state, 1);
> >>>>>
> >>>>>  	const uint8_t awb_state = ANDROID_CONTROL_AWB_STATE_CONVERGED;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_CONTROL_AWB_STATE,
> >>>>> -					&awb_state, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_CONTROL_AWB_STATE, &awb_state, 1);
> >>>>>
> >>>>>  	const uint8_t awb_lock = ANDROID_CONTROL_AWB_LOCK_OFF;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_CONTROL_AWB_LOCK,
> >>>>> -					&awb_lock, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_CONTROL_AWB_LOCK, &awb_lock, 1);
> >>>>>
> >>>>>  	const uint8_t lens_state = ANDROID_LENS_STATE_STATIONARY;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_LENS_STATE,
> >>>>> -					&lens_state, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_LENS_STATE, &lens_state, 1);
> >>>>>
> >>>>>  	int32_t sensorSizes[] = {
> >>>>>  		0, 0, 2560, 1920,
> >>>>>  	};
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_SCALER_CROP_REGION,
> >>>>> -					sensorSizes, 4);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_SCALER_CROP_REGION, sensorSizes, 4);
> >>>>>
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_SENSOR_TIMESTAMP,
> >>>>> -					&timestamp, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_SENSOR_TIMESTAMP, &timestamp, 1);
> >>>>>
> >>>>>  	/* 33.3 msec */
> >>>>>  	const int64_t rolling_shutter_skew = 33300000;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_SENSOR_ROLLING_SHUTTER_SKEW,
> >>>>> -					&rolling_shutter_skew, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_SENSOR_ROLLING_SHUTTER_SKEW,
> >>>>> +				 &rolling_shutter_skew, 1);
> >>>>>
> >>>>>  	/* 16.6 msec */
> >>>>>  	const int64_t exposure_time = 16600000;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_SENSOR_EXPOSURE_TIME,
> >>>>> -					&exposure_time, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_SENSOR_EXPOSURE_TIME,
> >>>>> +				 &exposure_time, 1);
> >>>>>
> >>>>>  	const uint8_t lens_shading_map_mode =
> >>>>>  				ANDROID_STATISTICS_LENS_SHADING_MAP_MODE_OFF;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_STATISTICS_LENS_SHADING_MAP_MODE,
> >>>>> -					&lens_shading_map_mode, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_STATISTICS_LENS_SHADING_MAP_MODE,
> >>>>> +				 &lens_shading_map_mode, 1);
> >>>>>
> >>>>>  	const uint8_t scene_flicker = ANDROID_STATISTICS_SCENE_FLICKER_NONE;
> >>>>> -	ret = add_camera_metadata_entry(resultMetadata,
> >>>>> -					ANDROID_STATISTICS_SCENE_FLICKER,
> >>>>> -					&scene_flicker, 1);
> >>>>> -	METADATA_ASSERT(ret);
> >>>>> +	resultMetadata->addEntry(ANDROID_STATISTICS_SCENE_FLICKER,
> >>>>> +				 &scene_flicker, 1);
> >>>>
> >>>> Shouldn't you check if the metadata pack is valid ?
> >>>
> >>> Good point. Should we check here or in the caller ? As the caller would
> >>> then need a nullptr check I'm tempted to do so in the caller. Actually,
> >>> without a change to the code, the caller will operate correctly I
> >>> believe
> >>>
> >>>                 resultMetadata = getResultMetadata(descriptor->frameNumber,
> >>>                                                    libcameraBuffer->timestamp());
> >>>                 captureResult.result = resultMetadata->get();
> >>>
> >>> which will set captureResult.result to nullptr if resultMetadata is not
> >>> valid.
> >>
> >> Yeah, but in that case we should notify an error back to the stack.
> >
> > That makes sense. It should be a faily uncommon case though, is it would
> > be the result of a bug in our code, but bugs happen. I wonder what the
> > proper error recovery would be in that case.
> >
> >> What about:
> >>
> >>         resultMetadata = getResultMetadata(descriptor->frameNumber,
> >>                                            libcameraBuffer->timestamp());
> >> 	if (status == CAMERA3_BUFFER_STATUS_ERROR || !resultMetadata) {
> >> 		/* \todo Improve error handling. */
> >> 		notifyError(descriptor->frameNumber,
> >> 			    descriptor->buffers[0].stream);
> >> 	} else {
> >> 		notifyShutter(descriptor->frameNumber,
> >> 			      libcameraBuffer->timestamp());
> >>
> >> 		captureResult.partial_result = 1;
> >> 		captureResult.result = resultMetadata->get();
> >> 	}
> >>
> >> The drawback is that we're generating the result metadata even if
> >> status is set to CAMERA3_BUFFER_STATUS_ERROR.
> >
> > That I don't think we should do, as I expect the result metadata
> > generation will not be possible in case of CAMERA3_BUFFER_STATUS_ERROR
> > when we'll stop generating fake metadata.
> >
> > How about this ?
> >
> > 	if (status == CAMERA3_BUFFER_STATUS_OK) {
> > 		notifyShutter(descriptor->frameNumber,
> > 			      libcameraBuffer->timestamp());
> >
> > 		captureResult.partial_result = 1;
> > 		resultMetadata = getResultMetadata(descriptor->frameNumber,
> > 						   libcameraBuffer->timestamp());
> > 		captureResult.result = resultMetadata->get();
> > 	}
> >
> > 	if (status == CAMERA3_BUFFER_STATUS_ERROR || !captureResult.result) {
> > 		/* \todo Improve error handling. */
> > 		notifyError(descriptor->frameNumber,
> > 			    descriptor->buffers[0].stream);
> > 	}
> >
> > The last condition could be written if (!captureResult.result) as
> > CAMERA3_BUFFER_STATUS_ERROR implies !captureResult.result, but I'd
> > rather have both to make it explicit.
> 
> The only difference I see here is that we send up a shutter event and
> the if metadata generation fails we send back an error.
> 
> In the previous version was either an error or the shutter
> notification, not both.
> 
> I can't tell if this makes any difference to the camera stack to be
> honest.

Neither can I, and this shouldn't happen in the first place :-) If you
want to avoid it,

 	if (status == CAMERA3_BUFFER_STATUS_OK) {
 		captureResult.partial_result = 1;
 		resultMetadata = getResultMetadata(descriptor->frameNumber,
 						   libcameraBuffer->timestamp());
 		captureResult.result = resultMetadata->get();
 	}

 	if (status == CAMERA3_BUFFER_STATUS_OK && captureResult.result) {
 		notifyShutter(descriptor->frameNumber,
 			      libcameraBuffer->timestamp());
	} else {
 		/* \todo Improve error handling. */
 		notifyError(descriptor->frameNumber,
 			    descriptor->buffers[0].stream);
 	}

> >>>>>
> >>>>>  	return resultMetadata;
> >>>>>  }
> >>>>> diff --git a/src/android/camera_device.h b/src/android/camera_device.h
> >>>>> index 7897ba9dc5c7..65ba877a02ea 100644
> >>>>> --- a/src/android/camera_device.h
> >>>>> +++ b/src/android/camera_device.h
> >>>>> @@ -19,13 +19,7 @@
> >>>>>
> >>>>>  #include "message.h"
> >>>>>
> >>>>> -#define METADATA_ASSERT(_r)		\
> >>>>> -	do {				\
> >>>>> -		if (!(_r)) break;	\
> >>>>> -		LOG(HAL, Error) << "Error: " << __func__ << ":" << __LINE__; \
> >>>>> -		return nullptr;		\
> >>>>> -	} while(0);
> >>>>> -
> >>>>> +class CameraMetadata;
> >>>>>  class ThreadRpc;
> >>>>>
> >>>>>  class CameraDevice : public libcamera::Object
> >>>>> @@ -59,14 +53,15 @@ private:
> >>>>>
> >>>>>  	void notifyShutter(uint32_t frameNumber, uint64_t timestamp);
> >>>>>  	void notifyError(uint32_t frameNumber, camera3_stream_t *stream);
> >>>>> -	camera_metadata_t *getResultMetadata(int frame_number, int64_t timestamp);
> >>>>> +	std::unique_ptr<CameraMetadata> getResultMetadata(int frame_number,
> >>>>> +							  int64_t timestamp);
> >>>>>
> >>>>>  	bool running_;
> >>>>>  	std::shared_ptr<libcamera::Camera> camera_;
> >>>>>  	std::unique_ptr<libcamera::CameraConfiguration> config_;
> >>>>>
> >>>>> -	camera_metadata_t *staticMetadata_;
> >>>>> -	camera_metadata_t *requestTemplate_;
> >>>>> +	CameraMetadata *staticMetadata_;
> >>>>> +	CameraMetadata *requestTemplate_;
> >>>>>  	const camera3_callback_ops_t *callbacks_;
> >>>>>  };
> >>>>>

-- 
Regards,

Laurent Pinchart


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