tlbmc/hal/sysfs/iio.cc

#include "tlbmc/hal/sysfs/iio.h"

#include <fstream>
#include <string>

#include "absl/status/status.h"
#include "absl/status/statusor.h"
#include "absl/strings/ascii.h"
#include "absl/strings/str_cat.h"
#include "boost/filesystem.hpp"  // NOLINT: boost::filesystem is commonly used in BMC
#include "sensor.pb.h"

namespace milotic_tlbmc {

absl::StatusOr<boost::filesystem::path> IioSysfs::GetIioDeviceDirectory(
    const std::string& root_iio_device_name) const {
  boost::filesystem::path path(config_.iio_sysfs_path);
  boost::system::error_code ec;

  if (!boost::filesystem::exists(path, ec) || ec ||
      !boost::filesystem::is_directory(path, ec) || ec) {
    return absl::NotFoundError(
        absl::StrCat("IIO sysfs path not found: ", path.string()));
  }

  boost::filesystem::directory_iterator it(path, ec);
  if (ec) {
    return absl::UnavailableError(
        absl::StrCat("Could not iterate directory: ", path.string()));
  }
  for (const auto& entry : it) {
    if (!boost::filesystem::is_directory(entry.path(), ec) || ec) {
      continue;
    }

    boost::filesystem::path name_file_path = entry.path() / "name";
    if (!boost::filesystem::exists(name_file_path, ec) || ec) {
      continue;
    }

    std::ifstream name_file(name_file_path.string());
    if (!name_file.is_open()) {
      continue;
    }
    std::string content;
    std::getline(name_file, content);

    absl::StripTrailingAsciiWhitespace(&content);

    if (content == root_iio_device_name) {
      return boost::filesystem::path(entry.path());
    }
  }

  return absl::NotFoundError(absl::StrCat("Device ", root_iio_device_name,
                                          " not found in ", path.string()));
}

absl::StatusOr<boost::filesystem::path> IioSysfs::GetSensorPath(
    const std::string& device_name, const std::string& channel_name) const {
  absl::StatusOr<boost::filesystem::path> device_path =
      GetIioDeviceDirectory(device_name);
  if (!device_path.ok()) {
    return device_path.status();
  }
  boost::filesystem::path sensor_file_path = device_path.value() / channel_name;

  boost::system::error_code ec;
  if (!boost::filesystem::exists(sensor_file_path, ec) || ec) {
    return absl::NotFoundError(
        absl::StrCat("Sensor file not found: ", sensor_file_path.string()));
  }

  return sensor_file_path;
}

}  // namespace milotic_tlbmc