1 files changed, 208 insertions, 0 deletions
diff --git a/src/android/camera_hal_config.cpp b/src/android/camera_hal_config.cpp
new file mode 100644
index 00000000..7ef451ef
--- /dev/null
+++ b/src/android/camera_hal_config.cpp
@@ -0,0 +1,208 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2021, Google Inc.
+ *
+ * Camera HAL configuration file manager
+ */
+#include "camera_hal_config.h"
+
+#include <stdlib.h>
+#include <string>
+
+#include <libcamera/base/file.h>
+#include <libcamera/base/log.h>
+
+#include "libcamera/internal/yaml_parser.h"
+
+#include <hardware/camera3.h>
+
+using namespace libcamera;
+
+LOG_DEFINE_CATEGORY(HALConfig)
+
+class CameraHalConfig::Private : public Extensible::Private
+{
+	LIBCAMERA_DECLARE_PUBLIC(CameraHalConfig)
+
+public:
+	Private();
+
+	int parseConfigFile(File &file, std::map<std::string, CameraConfigData> *cameras);
+
+private:
+	int parseCameraConfigData(const std::string &cameraId, const YamlObject &);
+	int parseLocation(const YamlObject &, CameraConfigData &cameraConfigData);
+	int parseRotation(const YamlObject &, CameraConfigData &cameraConfigData);
+
+	std::map<std::string, CameraConfigData> *cameras_;
+};
+
+CameraHalConfig::Private::Private()
+{
+}
+
+int CameraHalConfig::Private::parseConfigFile(File &file,
+					      std::map<std::string, CameraConfigData> *cameras)
+{
+	/*
+	 * Parse the HAL properties.
+	 *
+	 * Each camera properties block is a list of properties associated
+	 * with the ID (as assembled by CameraSensor::generateId()) of the
+	 * camera they refer to.
+	 *
+	 * cameras:
+	 *   "camera0 id":
+	 *     location: value
+	 *     rotation: value
+	 *     ...
+	 *
+	 *   "camera1 id":
+	 *     location: value
+	 *     rotation: value
+	 *     ...
+	 */
+
+	cameras_ = cameras;
+
+	std::unique_ptr<YamlObject> root = YamlParser::parse(file);
+	if (!root)
+		return -EINVAL;
+
+	if (!root->isDictionary())
+		return -EINVAL;
+
+	/* Parse property "cameras" */
+	if (!root->contains("cameras"))
+		return -EINVAL;
+
+	const YamlObject &yamlObjectCameras = (*root)["cameras"];
+
+	if (!yamlObjectCameras.isDictionary())
+		return -EINVAL;
+
+	for (const auto &[cameraId, configData] : yamlObjectCameras.asDict()) {
+		if (parseCameraConfigData(cameraId, configData))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+int CameraHalConfig::Private::parseCameraConfigData(const std::string &cameraId,
+						    const YamlObject &cameraObject)
+
+{
+	if (!cameraObject.isDictionary())
+		return -EINVAL;
+
+	CameraConfigData &cameraConfigData = (*cameras_)[cameraId];
+
+	/* Parse property "location" */
+	if (parseLocation(cameraObject, cameraConfigData))
+		return -EINVAL;
+
+	/* Parse property "rotation" */
+	if (parseRotation(cameraObject, cameraConfigData))
+		return -EINVAL;
+
+	return 0;
+}
+
+int CameraHalConfig::Private::parseLocation(const YamlObject &cameraObject,
+					    CameraConfigData &cameraConfigData)
+{
+	if (!cameraObject.contains("location"))
+		return -EINVAL;
+
+	std::string location = cameraObject["location"].get<std::string>("");
+
+	if (location == "front")
+		cameraConfigData.facing = CAMERA_FACING_FRONT;
+	else if (location == "back")
+		cameraConfigData.facing = CAMERA_FACING_BACK;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+int CameraHalConfig::Private::parseRotation(const YamlObject &cameraObject,
+					    CameraConfigData &cameraConfigData)
+{
+	if (!cameraObject.contains("rotation"))
+		return -EINVAL;
+
+	int32_t rotation = cameraObject["rotation"].get<int32_t>(-1);
+
+	if (rotation < 0 || rotation >= 360) {
+		LOG(HALConfig, Error)
+			<< "Unknown rotation: " << rotation;
+		return -EINVAL;
+	}
+
+	cameraConfigData.rotation = rotation;
+	return 0;
+}
+
+CameraHalConfig::CameraHalConfig()
+	: Extensible(std::make_unique<Private>()), exists_(false), valid_(false)
+{
+	parseConfigurationFile();
+}
+
+/*
+ * Open the HAL configuration file and validate its content.
+ * Return 0 on success, a negative error code otherwise
+ * retval -ENOENT The configuration file is not available
+ * retval -EINVAL The configuration file is available but not valid
+ */
+int CameraHalConfig::parseConfigurationFile()
+{
+	std::string filePath = LIBCAMERA_SYSCONF_DIR "/camera_hal.yaml";
+
+	File file(filePath);
+	if (!file.exists()) {
+		LOG(HALConfig, Debug)
+			<< "Configuration file: \"" << filePath << "\" not found";
+		return -ENOENT;
+	}
+
+	if (!file.open(File::OpenModeFlag::ReadOnly)) {
+		int ret = file.error();
+		LOG(HALConfig, Error) << "Failed to open configuration file "
+				      << filePath << ": " << strerror(-ret);
+		return ret;
+	}
+
+	exists_ = true;
+
+	int ret = _d()->parseConfigFile(file, &cameras_);
+	if (ret)
+		return -EINVAL;
+
+	valid_ = true;
+
+	for (const auto &c : cameras_) {
+		const std::string &cameraId = c.first;
+		const CameraConfigData &camera = c.second;
+		LOG(HALConfig, Debug) << "'" << cameraId << "' "
+				      << "(" << camera.facing << ")["
+				      << camera.rotation << "]";
+	}
+
+	return 0;
+}
+
+const CameraConfigData *CameraHalConfig::cameraConfigData(const std::string &cameraId) const
+{
+	const auto &it = cameras_.find(cameraId);
+	if (it == cameras_.end()) {
+		LOG(HALConfig, Error)
+			<< "Camera '" << cameraId
+			<< "' not described in the HAL configuration file";
+		return nullptr;
+	}
+
+	return &it->second;
+}