cam: Move camera acquire to the CameraSession class

Continue moving towards making the CameraSession class the central point
to handle a camera by moving the camera acquire operation. A new
CameraSession::camera() function is needed to allow access to the camera
from CamApp.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/cam/camera_session.cpp

@@ -19,11 +19,30 @@
 
 using namespace libcamera;
 
-CameraSession::CameraSession(std::shared_ptr<Camera> camera,
+CameraSession::CameraSession(CameraManager *cm,
 			     const OptionsParser::Options &options)
-	: camera_(camera), last_(0), queueCount_(0), captureCount_(0),
+	: last_(0), queueCount_(0), captureCount_(0),
 	  captureLimit_(0), printMetadata_(false)
 {
+	const std::string &cameraId = options[OptCamera];
+	char *endptr;
+	unsigned long index = strtoul(cameraId.c_str(), &endptr, 10);
+	if (*endptr == '\0' && index > 0 && index <= cm->cameras().size())
+		camera_ = cm->cameras()[index - 1];
+	else
+		camera_ = cm->get(cameraId);
+
+	if (!camera_) {
+		std::cerr << "Camera " << cameraId << " not found" << std::endl;
+		return;
+	}
+
+	if (camera_->acquire()) {
+		std::cerr << "Failed to acquire camera " << cameraId
+			  << std::endl;
+		return;
+	}
+
 	StreamRoles roles = StreamKeyValueParser::roles(options[OptStream]);
 
 	std::unique_ptr<CameraConfiguration> config =
@@ -64,6 +83,12 @@ CameraSession::CameraSession(std::shared_ptr<Camera> camera,
 	config_ = std::move(config);
 }
 
+CameraSession::~CameraSession()
+{
+	if (camera_)
+		camera_->release();
+}
+
 int CameraSession::start(const OptionsParser::Options &options)
 {
 	int ret;

src/cam/camera_session.h

@@ -14,6 +14,7 @@
 #include <libcamera/base/signal.h>
 
 #include <libcamera/camera.h>
+#include <libcamera/camera_manager.h>
 #include <libcamera/framebuffer.h>
 #include <libcamera/framebuffer_allocator.h>
 #include <libcamera/request.h>
@@ -25,10 +26,13 @@
 class CameraSession
 {
 public:
-	CameraSession(std::shared_ptr<libcamera::Camera> camera,
+	CameraSession(libcamera::CameraManager *cm,
 		      const OptionsParser::Options &options);
+	~CameraSession();
 
 	bool isValid() const { return config_ != nullptr; }
+
+	libcamera::Camera *camera() { return camera_.get(); }
 	libcamera::CameraConfiguration *config() { return config_.get(); }
 
 	int start(const OptionsParser::Options &options);

src/cam/main.cpp

@@ -51,7 +51,6 @@ private:
 	OptionsParser::Options options_;
 	CameraManager *cm_;
 
-	std::shared_ptr<Camera> camera_;
 	std::unique_ptr<CameraSession> session_;
 
 	EventLoop loop_;
@@ -60,7 +59,7 @@ private:
 CamApp *CamApp::app_ = nullptr;
 
 CamApp::CamApp()
-	: cm_(nullptr), camera_(nullptr)
+	: cm_(nullptr)
 {
 	CamApp::app_ = this;
 }
@@ -93,37 +92,16 @@ int CamApp::init(int argc, char **argv)
 	}
 
 	if (options_.isSet(OptCamera)) {
-		const std::string &cameraId = options_[OptCamera];
+		session_ = std::make_unique<CameraSession>(cm_, options_);
-		char *endptr;
-		unsigned long index = strtoul(cameraId.c_str(), &endptr, 10);
-		if (*endptr == '\0' && index > 0 && index <= cm_->cameras().size())
-			camera_ = cm_->cameras()[index - 1];
-		else
-			camera_ = cm_->get(cameraId);
-
-		if (!camera_) {
-			std::cout << "Camera "
-				  << std::string(options_[OptCamera])
-				  << " not found" << std::endl;
-			cleanup();
-			return -ENODEV;
-		}
-
-		if (camera_->acquire()) {
-			std::cout << "Failed to acquire camera" << std::endl;
-			cleanup();
-			return -EINVAL;
-		}
-
-		std::cout << "Using camera " << camera_->id() << std::endl;
-
-		session_ = std::make_unique<CameraSession>(camera_, options_);
 		if (!session_->isValid()) {
 			std::cout << "Failed to create camera session" << std::endl;
 			cleanup();
 			return -EINVAL;
 		}
 
+		std::cout << "Using camera " << session_->camera()->id()
+			  << std::endl;
+
 		session_->captureDone.connect(this, &CamApp::captureDone);
 	}
 
@@ -138,11 +116,6 @@ int CamApp::init(int argc, char **argv)
 
 void CamApp::cleanup()
 {
-	if (camera_) {
-		camera_->release();
-		camera_.reset();
-	}
-
 	session_.reset();
 
 	cm_->stop();
@@ -214,13 +187,13 @@ int CamApp::parseOptions(int argc, char *argv[])
 
 int CamApp::listControls()
 {
-	if (!camera_) {
+	if (!session_) {
 		std::cout << "Cannot list controls without a camera"
 			  << std::endl;
 		return -EINVAL;
 	}
 
-	for (const auto &ctrl : camera_->controls()) {
+	for (const auto &ctrl : session_->camera()->controls()) {
 		const ControlId *id = ctrl.first;
 		const ControlInfo &info = ctrl.second;
 
@@ -233,13 +206,13 @@ int CamApp::listControls()
 
 int CamApp::listProperties()
 {
-	if (!camera_) {
+	if (!session_) {
 		std::cout << "Cannot list properties without a camera"
 			  << std::endl;
 		return -EINVAL;
 	}
 
-	for (const auto &prop : camera_->properties()) {
+	for (const auto &prop : session_->camera()->properties()) {
 		const ControlId *id = properties::properties.at(prop.first);
 		const ControlValue &value = prop.second;
 
@@ -252,7 +225,7 @@ int CamApp::listProperties()
 
 int CamApp::infoConfiguration()
 {
-	if (!camera_) {
+	if (!session_) {
 		std::cout << "Cannot print stream information without a camera"
 			  << std::endl;
 		return -EINVAL;
@@ -328,7 +301,7 @@ int CamApp::run()
 	}
 
 	if (options_.isSet(OptCapture)) {
-		if (!camera_) {
+		if (!session_) {
 			std::cout << "Can't capture without a camera" << std::endl;
 			return -ENODEV;
 		}