Index: device/generic_sensor/linux/platform_sensor_utils_linux.cc |
diff --git a/device/generic_sensor/linux/platform_sensor_utils_linux.cc b/device/generic_sensor/linux/platform_sensor_utils_linux.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..49511ce8862187696eaafd1c764aee0711b44b88 |
--- /dev/null |
+++ b/device/generic_sensor/linux/platform_sensor_utils_linux.cc |
@@ -0,0 +1,94 @@ |
+// Copyright 2016 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#include "device/generic_sensor/linux/platform_sensor_utils_linux.h" |
+ |
+#include "base/files/file_enumerator.h" |
+#include "base/files/file_util.h" |
+#include "base/strings/string_number_conversions.h" |
+#include "base/strings/string_util.h" |
+#include "base/threading/thread_restrictions.h" |
+#include "device/generic_sensor/linux/sensor_data_linux.h" |
+#include "device/generic_sensor/public/cpp/sensor_reading.h" |
+ |
+namespace device { |
+ |
+namespace { |
+ |
+bool InitSensorPaths(const std::vector<std::string>& input_names, |
+ const char* base_path, |
+ std::vector<base::FilePath>* sensor_paths) { |
+ // Search the iio/devices directory for a subdirectory (eg "device0" or |
+ // "iio:device0") that contains the specified input_name file (eg |
+ // "in_illuminance_input" or "in_illuminance0_input"). |
+ base::FileEnumerator dir_enumerator(base::FilePath(base_path), false, |
+ base::FileEnumerator::DIRECTORIES); |
+ for (base::FilePath check_path = dir_enumerator.Next(); !check_path.empty(); |
+ check_path = dir_enumerator.Next()) { |
+ for (auto const& file_name : input_names) { |
+ base::FilePath full_path = check_path.Append(file_name); |
+ if (base::PathExists(full_path)) { |
+ sensor_paths->push_back(full_path); |
+ return true; |
+ } |
+ } |
+ } |
+ return false; |
+} |
+ |
+bool GetSensorFilePaths(const SensorDataLinux& data, |
+ std::vector<base::FilePath>* sensor_paths) { |
+ DCHECK(sensor_paths->empty()); |
+ // Depending on a sensor, there can be up to three sets of files that need |
+ // to be checked. If one of three files is not found, a sensor is |
+ // treated as a non-existing one. |
+ for (auto const& file_names : data.sensor_file_names) { |
+ // Supply InitSensorPaths() with a set of files. |
+ // Only one file from each set should be found. |
+ if (!InitSensorPaths(file_names, data.base_path_sensor_linux, sensor_paths)) |
+ return false; |
+ } |
+ return true; |
+} |
+ |
+} // namespace |
+ |
+// static |
+std::unique_ptr<SensorReader> SensorReader::Create( |
+ const SensorDataLinux& data) { |
+ base::ThreadRestrictions::AssertIOAllowed(); |
+ std::vector<base::FilePath> sensor_paths; |
+ if (!GetSensorFilePaths(data, &sensor_paths)) |
+ return nullptr; |
+ return base::WrapUnique(new SensorReader(std::move(sensor_paths))); |
+} |
+ |
+SensorReader::SensorReader(std::vector<base::FilePath> sensor_paths) |
+ : sensor_paths_(std::move(sensor_paths)) { |
+ DCHECK(!sensor_paths_.empty()); |
+} |
+ |
+SensorReader::~SensorReader() = default; |
+ |
+bool SensorReader::ReadSensorReading(SensorReading* reading) { |
+ base::ThreadRestrictions::AssertIOAllowed(); |
+ SensorReading readings; |
+ DCHECK_LE(sensor_paths_.size(), arraysize(readings.values)); |
+ int i = 0; |
+ for (const auto& path : sensor_paths_) { |
+ std::string new_read_value; |
+ if (!base::ReadFileToString(path, &new_read_value)) |
+ return false; |
+ |
+ double new_value = 0; |
+ base::TrimWhitespaceASCII(new_read_value, base::TRIM_ALL, &new_read_value); |
+ if (!base::StringToDouble(new_read_value, &new_value)) |
+ return false; |
+ readings.values[i++] = new_value; |
+ } |
+ *reading = readings; |
+ return true; |
+} |
+ |
+} // namespace device |