LCamDev: implement configureSessionModeCReq

We can, theoretically, now change the v4l camera's mode.

commonLibs/lcameraDev/sessionModeConfigure.h

@@ -0,0 +1,34 @@
+#ifndef LCAMERA_DEV_SESSION_MODE_CONFIGURE_H
+#define LCAMERA_DEV_SESSION_MODE_CONFIGURE_H
+
+#include <cameraModeRequest.h>
+#include <cameraSession.h>
+#include <memory>
+
+namespace libcamera {
+class CameraConfiguration;
+}
+
+namespace lcamera_dev {
+
+enum class ConfigureSessionModeStatus
+{
+	Configured,
+	NoOpAlreadyConfigured,
+	RejectedConflictingRequest,
+};
+
+ConfigureSessionModeStatus applyModeRequestToSessionState(
+	CameraSessionResources& resources,
+	const LcameraDevCameraModeRequest& request,
+	const LcameraDevConfiguredCameraMode& resolvedMode,
+	std::shared_ptr<libcamera::CameraConfiguration> heldConfiguration);
+
+LcameraDevConfiguredCameraMode configureLibcameraSessionMode(
+	const std::shared_ptr<libcamera::Camera>& camera,
+	const LcameraDevCameraModeRequest& request,
+	std::shared_ptr<libcamera::CameraConfiguration>& heldConfiguration);
+
+} // namespace lcamera_dev
+
+#endif // LCAMERA_DEV_SESSION_MODE_CONFIGURE_H