lcameraDev: Add session mgr lib for libcamera device binding

commonLibs/lcameraDev/cameraManagerState.cpp

@@ -0,0 +1,251 @@
+#include <boostAsioLinkageFix.h>
+
+#include <cameraIdentity.h>
+#include <cameraManagerState.h>
+#include <selectorParse.h>
+#include <selectorResolve.h>
+#include <algorithm>
+#include <stdexcept>
+
+namespace lcamera_dev {
+
+namespace {
+
+static LcameraDevState lcameraDevState;
+
+void startCameraManager(CameraManagerResources& resources)
+{
+	resources.cameraManager = std::make_unique<libcamera::CameraManager>();
+
+	if (resources.cameraManager->start())
+	{
+		resources.cameraManager.reset();
+		throw std::runtime_error(
+			"lcameraDev: failed to start libcamera CameraManager");
+	}
+}
+
+void stopCameraManager(CameraManagerResources& resources)
+{
+	if (!resources.cameraManager) {
+		return;
+	}
+
+	resources.cameraManager->stop();
+	resources.cameraManager.reset();
+}
+
+std::shared_ptr<libcamera::Camera> findCameraById(
+	const std::vector<std::shared_ptr<libcamera::Camera>>& cameras,
+	const std::string& cameraId)
+{
+	for (const std::shared_ptr<libcamera::Camera>& camera : cameras)
+	{
+		if (camera && camera->id() == cameraId) {
+			return camera;
+		}
+	}
+
+	return nullptr;
+}
+
+} // namespace
+
+LcameraDevState& getLcameraDevState()
+{
+	return lcameraDevState;
+}
+
+std::vector<std::shared_ptr<libcamera::Camera>> listLibcameraCameras()
+{
+	LcameraDevState& state = getLcameraDevState();
+	if (!state.isInitialized || !state.managerState.rsrc.cameraManager) {
+		return {};
+	}
+
+	return state.managerState.rsrc.cameraManager->cameras();
+}
+
+void lcameraDevMain(
+	const std::shared_ptr<sscl::ComponentThread>& componentThread)
+{
+	LcameraDevState& state = getLcameraDevState();
+	if (state.isInitialized) {
+		return;
+	}
+
+	if (!componentThread)
+	{
+		throw std::runtime_error(
+			"lcameraDev_main: componentThread must be non-null");
+	}
+
+	startCameraManager(state.managerState.rsrc);
+	state.componentThread = componentThread;
+	state.isInitialized = true;
+}
+
+void lcameraDevExit()
+{
+	LcameraDevState& state = getLcameraDevState();
+	if (!state.isInitialized) {
+		return;
+	}
+
+	CameraManagerResources& resources = state.managerState.rsrc;
+	for (auto& entry : resources.sessionsByCameraId)
+	{
+		std::shared_ptr<CameraSession> session = entry.second;
+		if (!session || !session->s.rsrc.camera) {
+			continue;
+		}
+
+		session->s.rsrc.camera->release();
+	}
+
+	resources.sessionsByCameraId.clear();
+	stopCameraManager(resources);
+
+	state.componentThread.reset();
+	state.isInitialized = false;
+}
+
+sscl::co::ViralNonPostingInvoker<LcameraDevGetOrCreateResult>
+getOrCreateDeviceSessionCReq(const std::string& deviceSelector)
+{
+	if (deviceSelector.empty())
+	{
+		throw std::runtime_error(
+			"lcameraDev_getOrCreateDeviceCReq: deviceSelector is empty");
+	}
+
+	LcameraDevState& state = getLcameraDevState();
+
+	sscl::co::CoQutex::ReleaseHandle managerGuard =
+		co_await state.managerState.lock.getAcquireInvocationAndSuspensionPolicy();
+
+	const std::vector<SelectorCriterion> criteria =
+		parseDeviceSelector(deviceSelector);
+	const std::vector<std::shared_ptr<libcamera::Camera>> cameras =
+		state.managerState.rsrc.cameraManager->cameras();
+	const std::vector<CameraIdentityRecord> identityRecords =
+		buildIdentityRecords(cameras);
+
+	const CameraIdentityRecord resolvedRecord =
+		resolveSelectorAgainstRecords(criteria, identityRecords);
+	const std::string& resolvedCameraId = resolvedRecord.id;
+
+	auto sessionIt =
+		state.managerState.rsrc.sessionsByCameraId.find(resolvedCameraId);
+
+	if (sessionIt != state.managerState.rsrc.sessionsByCameraId.end())
+	{
+		std::shared_ptr<CameraSession> session = sessionIt->second;
+		sscl::co::CoQutex::ReleaseHandle sessionGuard =
+			co_await session->s.lock.getAcquireInvocationAndSuspensionPolicy();
+
+		session->incrementRefcount();
+
+		LcameraDevGetOrCreateResult result;
+		result.deviceSession = session;
+		result.resolvedIdentity = session->getIdentityRecord();
+		co_return result;
+	}
+
+	std::shared_ptr<libcamera::Camera> camera =
+		findCameraById(cameras, resolvedCameraId);
+	if (!camera)
+	{
+		throw std::runtime_error(
+			"lcameraDev: resolved camera is no longer available: "
+			+ resolvedCameraId);
+	}
+
+	if (camera->acquire())
+	{
+		throw std::runtime_error(
+			"lcameraDev: failed to acquire camera: " + resolvedCameraId);
+	}
+
+	std::shared_ptr<CameraSession> session =
+		std::make_shared<CameraSession>(resolvedRecord, camera);
+
+	session->incrementRefcount();
+	state.managerState.rsrc.sessionsByCameraId.emplace(
+		resolvedCameraId, session);
+
+	LcameraDevGetOrCreateResult result;
+	result.deviceSession = session;
+	result.resolvedIdentity = session->getIdentityRecord();
+	co_return result;
+}
+
+sscl::co::ViralNonPostingInvoker<void>
+releaseDeviceSessionCReq(
+	const std::shared_ptr<CameraSession>& deviceSession)
+{
+	if (!deviceSession) { co_return; }
+
+	LcameraDevState& state = getLcameraDevState();
+	sscl::co::CoQutex::ReleaseHandle managerGuard =
+		co_await state.managerState.lock.getAcquireInvocationAndSuspensionPolicy();
+
+	const auto sessionIt = std::find_if(
+		state.managerState.rsrc.sessionsByCameraId.begin(),
+		state.managerState.rsrc.sessionsByCameraId.end(),
+		[&deviceSession](const auto& entry) {
+			return entry.second == deviceSession;
+		});
+
+	if (sessionIt == state.managerState.rsrc.sessionsByCameraId.end()) {
+		co_return;
+	}
+
+	bool shouldDestroy = false;
+	{
+		sscl::co::CoQutex::ReleaseHandle sessionGuard =
+			co_await deviceSession->s.lock.getAcquireInvocationAndSuspensionPolicy();
+
+		shouldDestroy = deviceSession->decrementRefcount();
+	}
+
+	if (!shouldDestroy) {
+		co_return;
+	}
+
+	if (deviceSession->s.rsrc.camera) {
+		deviceSession->s.rsrc.camera->release();
+	}
+
+	state.managerState.rsrc.sessionsByCameraId.erase(sessionIt);
+	co_return;
+}
+
+sscl::co::ViralNonPostingInvoker<std::vector<LcameraDevCameraInfo>>
+enumerateCamerasCReq()
+{
+	LcameraDevState& state = getLcameraDevState();
+	sscl::co::CoQutex::ReleaseHandle managerGuard =
+		co_await state.managerState.lock.getAcquireInvocationAndSuspensionPolicy();
+
+	const std::vector<std::shared_ptr<libcamera::Camera>> cameras =
+		state.managerState.rsrc.cameraManager->cameras();
+	const std::vector<CameraIdentityRecord> identityRecords =
+		buildIdentityRecords(cameras);
+
+	std::vector<LcameraDevCameraInfo> cameraInfos;
+	cameraInfos.reserve(identityRecords.size());
+
+	for (const CameraIdentityRecord& record : identityRecords)
+	{
+		cameraInfos.push_back(LcameraDevCameraInfo{
+			record.id,
+			record.model,
+			record.locationLabel
+		});
+	}
+
+	co_return cameraInfos;
+}
+
+} // namespace lcamera_dev