/* SPDX-License-Identifier: LGPL-2.1-or-later */ /* * Copyright (C) 2021, Google Inc. * * camera_hal_config.cpp - Camera HAL configuration file manager */ #include "camera_hal_config.h" #if defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE < 8 #include <experimental/filesystem> namespace std { namespace filesystem = std::experimental::filesystem; } #else #include <filesystem> #endif #include <stdlib.h> #include <string> #include <hardware/camera3.h> #include <libcamera/base/log.h> #include <libcamera/internal/yaml_parser.h> using namespace libcamera; LOG_DEFINE_CATEGORY(HALConfig) class CameraHalConfig::Private : public Extensible::Private { LIBCAMERA_DECLARE_PUBLIC(CameraHalConfig) public: Private(); int parseConfigFile(FILE *fh, 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 *fh, 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(fh); 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; std::vector<std::string> cameraIds = yamlObjectCameras.memberNames(); for (const std::string &cameraId : cameraIds) { if (parseCameraConfigData(cameraId, yamlObjectCameras[cameraId])) 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::filesystem::path filePath = LIBCAMERA_SYSCONF_DIR; filePath /= "camera_hal.yaml"; if (!std::filesystem::is_regular_file(filePath)) { LOG(HALConfig, Debug) << "Configuration file: \"" << filePath << "\" not found"; return -ENOENT; } FILE *fh = fopen(filePath.c_str(), "r"); if (!fh) { int ret = -errno; LOG(HALConfig, Error) << "Failed to open configuration file " << filePath << ": " << strerror(-ret); return ret; } exists_ = true; int ret = _d()->parseConfigFile(fh, &cameras_); fclose(fh); 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; }