libcamera: pipeline_handler: Return unique_ptr from generateConfiguration()

The PipelineHandler::generateConfiguration() function allocates a
CameraConfiguration instance and returns it. The ownership of the
instance is transferred to the caller. This is a perfect match for a
std::unique_ptr<>, which the Camera::generateConfiguration() function
already returns. Update PipelineHandler::generateConfiguration() to
match it. This fixes a memory leak in one of the error return paths in
the IPU3 pipeline handler.

While at it, update the Camera::generateConfiguration() function
documentation to drop the sentence that describes the ownership
transfer, as that is implied by usage of std::unique_ptr<>.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

8 files changed, 37 insertions, 33 deletions

diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index f0575c13..c4f65c1a 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -934,8 +934,7 @@ const std::set<Stream *> &Camera::streams() const
  * \context This function is \threadsafe.
  *
  * \return A CameraConfiguration if the requested roles can be satisfied, or a
- * null pointer otherwise. The ownership of the returned configuration is
- * passed to the caller.
+ * null pointer otherwise.
  */
 std::unique_ptr<CameraConfiguration> Camera::generateConfiguration(const StreamRoles &roles)
 {
@@ -949,7 +948,8 @@ std::unique_ptr<CameraConfiguration> Camera::generateConfiguration(const StreamR
 	if (roles.size() > streams().size())
 		return nullptr;
 
-	CameraConfiguration *config = d->pipe_->generateConfiguration(this, roles);
+	std::unique_ptr<CameraConfiguration> config =
+		d->pipe_->generateConfiguration(this, roles);
 	if (!config) {
 		LOG(Camera, Debug)
 			<< "Pipeline handler failed to generate configuration";
@@ -966,7 +966,7 @@ std::unique_ptr<CameraConfiguration> Camera::generateConfiguration(const StreamR
 
 	LOG(Camera, Debug) << msg.str();
 
-	return std::unique_ptr<CameraConfiguration>(config);
+	return config;
 }
 
 /**
diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 3b892d96..e4d79ea4 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -136,7 +136,7 @@ public:
 
 	PipelineHandlerIPU3(CameraManager *manager);
 
-	CameraConfiguration *generateConfiguration(Camera *camera,
+	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
 		const StreamRoles &roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
@@ -424,11 +424,12 @@ PipelineHandlerIPU3::PipelineHandlerIPU3(CameraManager *manager)
 {
 }
 
-CameraConfiguration *PipelineHandlerIPU3::generateConfiguration(Camera *camera,
-								const StreamRoles &roles)
+std::unique_ptr<CameraConfiguration>
+PipelineHandlerIPU3::generateConfiguration(Camera *camera, const StreamRoles &roles)
 {
 	IPU3CameraData *data = cameraData(camera);
-	IPU3CameraConfiguration *config = new IPU3CameraConfiguration(data);
+	std::unique_ptr<IPU3CameraConfiguration> config =
+		std::make_unique<IPU3CameraConfiguration>(data);
 
 	if (roles.empty())
 		return config;
@@ -494,7 +495,6 @@ CameraConfiguration *PipelineHandlerIPU3::generateConfiguration(Camera *camera,
 		default:
 			LOG(IPU3, Error)
 				<< "Requested stream role not supported: " << role;
-			delete config;
 			return nullptr;
 		}
 
diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
index 1b599fcc..f15fa28b 100644
--- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
+++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
@@ -323,7 +323,8 @@ class PipelineHandlerRPi : public PipelineHandler
 public:
 	PipelineHandlerRPi(CameraManager *manager);
 
-	CameraConfiguration *generateConfiguration(Camera *camera, const StreamRoles &roles) override;
+	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
+		const StreamRoles &roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
 	int exportFrameBuffers(Camera *camera, Stream *stream,
@@ -561,11 +562,12 @@ PipelineHandlerRPi::PipelineHandlerRPi(CameraManager *manager)
 {
 }
 
-CameraConfiguration *PipelineHandlerRPi::generateConfiguration(Camera *camera,
-							       const StreamRoles &roles)
+std::unique_ptr<CameraConfiguration>
+PipelineHandlerRPi::generateConfiguration(Camera *camera, const StreamRoles &roles)
 {
 	RPiCameraData *data = cameraData(camera);
-	CameraConfiguration *config = new RPiCameraConfiguration(data);
+	std::unique_ptr<CameraConfiguration> config =
+		std::make_unique<RPiCameraConfiguration>(data);
 	V4L2SubdeviceFormat sensorFormat;
 	unsigned int bufferCount;
 	PixelFormat pixelFormat;
@@ -640,13 +642,11 @@ CameraConfiguration *PipelineHandlerRPi::generateConfiguration(Camera *camera,
 		default:
 			LOG(RPI, Error) << "Requested stream role not supported: "
 					<< role;
-			delete config;
 			return nullptr;
 		}
 
 		if (rawCount > 1 || outCount > 2) {
 			LOG(RPI, Error) << "Invalid stream roles requested";
-			delete config;
 			return nullptr;
 		}
 
diff --git a/src/libcamera/pipeline/rkisp1/rkisp1.cpp b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
index 455ee2a0..56e4a62a 100644
--- a/src/libcamera/pipeline/rkisp1/rkisp1.cpp
+++ b/src/libcamera/pipeline/rkisp1/rkisp1.cpp
@@ -142,7 +142,7 @@ class PipelineHandlerRkISP1 : public PipelineHandler
 public:
 	PipelineHandlerRkISP1(CameraManager *manager);
 
-	CameraConfiguration *generateConfiguration(Camera *camera,
+	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
 		const StreamRoles &roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
@@ -539,7 +539,8 @@ PipelineHandlerRkISP1::PipelineHandlerRkISP1(CameraManager *manager)
  * Pipeline Operations
  */
 
-CameraConfiguration *PipelineHandlerRkISP1::generateConfiguration(Camera *camera,
+std::unique_ptr<CameraConfiguration>
+PipelineHandlerRkISP1::generateConfiguration(Camera *camera,
 	const StreamRoles &roles)
 {
 	RkISP1CameraData *data = cameraData(camera);
@@ -550,7 +551,8 @@ CameraConfiguration *PipelineHandlerRkISP1::generateConfiguration(Camera *camera
 		return nullptr;
 	}
 
-	CameraConfiguration *config = new RkISP1CameraConfiguration(camera, data);
+	std::unique_ptr<CameraConfiguration> config =
+		std::make_unique<RkISP1CameraConfiguration>(camera, data);
 	if (roles.empty())
 		return config;
 
@@ -595,7 +597,6 @@ CameraConfiguration *PipelineHandlerRkISP1::generateConfiguration(Camera *camera
 		default:
 			LOG(RkISP1, Warning)
 				<< "Requested stream role not supported: " << role;
-			delete config;
 			return nullptr;
 		}
 
diff --git a/src/libcamera/pipeline/simple/simple.cpp b/src/libcamera/pipeline/simple/simple.cpp
index 37b3e7ac..a32de7f3 100644
--- a/src/libcamera/pipeline/simple/simple.cpp
+++ b/src/libcamera/pipeline/simple/simple.cpp
@@ -311,8 +311,8 @@ class SimplePipelineHandler : public PipelineHandler
 public:
 	SimplePipelineHandler(CameraManager *manager);
 
-	CameraConfiguration *generateConfiguration(Camera *camera,
-						   const StreamRoles &roles) override;
+	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
+		const StreamRoles &roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
 	int exportFrameBuffers(Camera *camera, Stream *stream,
@@ -1037,12 +1037,12 @@ SimplePipelineHandler::SimplePipelineHandler(CameraManager *manager)
 {
 }
 
-CameraConfiguration *SimplePipelineHandler::generateConfiguration(Camera *camera,
-								  const StreamRoles &roles)
+std::unique_ptr<CameraConfiguration>
+SimplePipelineHandler::generateConfiguration(Camera *camera, const StreamRoles &roles)
 {
 	SimpleCameraData *data = cameraData(camera);
-	CameraConfiguration *config =
-		new SimpleCameraConfiguration(camera, data);
+	std::unique_ptr<CameraConfiguration> config =
+		std::make_unique<SimpleCameraConfiguration>(camera, data);
 
 	if (roles.empty())
 		return config;
diff --git a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
index a2819545..277465b7 100644
--- a/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo/uvcvideo.cpp
@@ -74,7 +74,7 @@ class PipelineHandlerUVC : public PipelineHandler
 public:
 	PipelineHandlerUVC(CameraManager *manager);
 
-	CameraConfiguration *generateConfiguration(Camera *camera,
+	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
 		const StreamRoles &roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
@@ -178,11 +178,13 @@ PipelineHandlerUVC::PipelineHandlerUVC(CameraManager *manager)
 {
 }
 
-CameraConfiguration *PipelineHandlerUVC::generateConfiguration(Camera *camera,
+std::unique_ptr<CameraConfiguration>
+PipelineHandlerUVC::generateConfiguration(Camera *camera,
 	const StreamRoles &roles)
 {
 	UVCCameraData *data = cameraData(camera);
-	CameraConfiguration *config = new UVCCameraConfiguration(data);
+	std::unique_ptr<CameraConfiguration> config =
+		std::make_unique<UVCCameraConfiguration>(data);
 
 	if (roles.empty())
 		return config;
diff --git a/src/libcamera/pipeline/vimc/vimc.cpp b/src/libcamera/pipeline/vimc/vimc.cpp
index f85d05f7..204f5ad7 100644
--- a/src/libcamera/pipeline/vimc/vimc.cpp
+++ b/src/libcamera/pipeline/vimc/vimc.cpp
@@ -84,7 +84,7 @@ class PipelineHandlerVimc : public PipelineHandler
 public:
 	PipelineHandlerVimc(CameraManager *manager);
 
-	CameraConfiguration *generateConfiguration(Camera *camera,
+	std::unique_ptr<CameraConfiguration> generateConfiguration(Camera *camera,
 		const StreamRoles &roles) override;
 	int configure(Camera *camera, CameraConfiguration *config) override;
 
@@ -189,11 +189,13 @@ PipelineHandlerVimc::PipelineHandlerVimc(CameraManager *manager)
 {
 }
 
-CameraConfiguration *PipelineHandlerVimc::generateConfiguration(Camera *camera,
+std::unique_ptr<CameraConfiguration>
+PipelineHandlerVimc::generateConfiguration(Camera *camera,
 	const StreamRoles &roles)
 {
 	VimcCameraData *data = cameraData(camera);
-	CameraConfiguration *config = new VimcCameraConfiguration(data);
+	std::unique_ptr<CameraConfiguration> config =
+		std::make_unique<VimcCameraConfiguration>(data);
 
 	if (roles.empty())
 		return config;
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 588a3db3..825aff5a 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -233,8 +233,7 @@ void PipelineHandler::unlockMediaDevices()
  * handler.
  *
  * \return A valid CameraConfiguration if the requested roles can be satisfied,
- * or a null pointer otherwise. The ownership of the returned configuration is
- * passed to the caller.
+ * or a null pointer otherwise.
  */
 
 /**