[sensors] Introduce Generic Sensor API interfaces

device/sensors/public/interfaces/sensor_struct_traits.cc

+// 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/sensors/public/interfaces/sensor_struct_traits.h"
+
+#define CHECK_ENUM(VALUE1, VALUE2)                                            \
+  static_assert(static_cast<int32_t>(VALUE1) == static_cast<int32_t>(VALUE2), \
+                "Enum value mismatch.")
+
+namespace mojo {
+
+// static
+double StructTraits<device::mojom::SensorConfiguration,
+                    device::PlatformSensorConfiguration>::
+    frequency(const device::PlatformSensorConfiguration& input) {
+  return input.GetFrequency();
+}
+
+// static
+bool StructTraits<device::mojom::SensorConfiguration,
+                  device::PlatformSensorConfiguration>::
+    Read(device::mojom::SensorConfigurationDataView data,
+         device::PlatformSensorConfiguration* out) {
+  out->SetFrequency(data.frequency());

[dcheng, 2016/07/06 02:07:29]

Is there an upper limit on frequency that to enforce here? Or is that enforced
somewhere else in the stack?

[shalamov, 2016/07/06 07:15:10]

Configuration is validated by concrete sensor implementation using bool
PlatformSensor::CheckSensorConfiguration(const PlatformSensorConfiguration&
configuration); method. Used in platform_sensor.cc
PlatformSensor::StartListening

[dcheng, 2016/07/06 09:12:04]

I think we can still provide an upper limit to clamp it here: then we don't need
to duplicate the validation in each PlatformSensor implementation. For example,
I think we clamp to 60Hz to reduce the risk of info leaks:
https://crbug.com/421691

+  return true;
+}
+
+// static asserts to verify that enums are in sync
+CHECK_ENUM(device::ReportingMode::ON_CHANGE,
+           device::mojom::ReportingMode::ON_CHANGE);
+CHECK_ENUM(device::ReportingMode::CONTINUOUS,
+           device::mojom::ReportingMode::CONTINUOUS);
+
+device::mojom::ReportingMode
+EnumTraits<device::mojom::ReportingMode, device::ReportingMode>::ToMojom(
+    device::ReportingMode reporting_mode) {
+  switch (reporting_mode) {
+    case device::ReportingMode::ON_CHANGE:
+      return device::mojom::ReportingMode::ON_CHANGE;
+    case device::ReportingMode::CONTINUOUS:
+      return device::mojom::ReportingMode::CONTINUOUS;
+  }
+  NOTREACHED();
+  return device::mojom::ReportingMode::ON_CHANGE;
+}
+
+// static
+bool EnumTraits<device::mojom::ReportingMode, device::ReportingMode>::FromMojom(
+    device::mojom::ReportingMode input,
+    device::ReportingMode* out) {
+  switch (input) {
+    case device::mojom::ReportingMode::ON_CHANGE:
+      *out = device::ReportingMode::ON_CHANGE;
+      return true;
+    case device::mojom::ReportingMode::CONTINUOUS:
+      *out = device::ReportingMode::CONTINUOUS;
+      return true;
+  }
+  return false;
+}
+
+// static asserts to verify that enums are in sync
+CHECK_ENUM(device::SensorType::FIRST, device::mojom::SensorType::FIRST);
+CHECK_ENUM(device::SensorType::AMBIENT_LIGHT,
+           device::mojom::SensorType::AMBIENT_LIGHT);
+CHECK_ENUM(device::SensorType::PROXIMITY, device::mojom::SensorType::PROXIMITY);
+CHECK_ENUM(device::SensorType::ACCELEROMETER,
+           device::mojom::SensorType::ACCELEROMETER);
+CHECK_ENUM(device::SensorType::GYROSCOPE, device::mojom::SensorType::GYROSCOPE);
+CHECK_ENUM(device::SensorType::PRESSURE, device::mojom::SensorType::PRESSURE);
+CHECK_ENUM(device::SensorType::LAST, device::mojom::SensorType::LAST);
+
+// static
+device::mojom::SensorType
+EnumTraits<device::mojom::SensorType, device::SensorType>::ToMojom(
+    device::SensorType sensor_type) {
+  switch (sensor_type) {
+    case device::SensorType::AMBIENT_LIGHT:
+      return device::mojom::SensorType::AMBIENT_LIGHT;
+    case device::SensorType::PROXIMITY:
+      return device::mojom::SensorType::PROXIMITY;
+    case device::SensorType::ACCELEROMETER:
+      return device::mojom::SensorType::ACCELEROMETER;
+    case device::SensorType::GYROSCOPE:
+      return device::mojom::SensorType::GYROSCOPE;
+    case device::SensorType::PRESSURE:
+      return device::mojom::SensorType::PRESSURE;
+  }
+  NOTREACHED();
+  return device::mojom::SensorType::AMBIENT_LIGHT;
+}
+
+// static
+bool EnumTraits<device::mojom::SensorType, device::SensorType>::FromMojom(
+    device::mojom::SensorType input,
+    device::SensorType* out) {
+  switch (input) {
+    case device::mojom::SensorType::AMBIENT_LIGHT:
+      *out = device::SensorType::AMBIENT_LIGHT;
+      return true;
+    case device::mojom::SensorType::PROXIMITY:
+      *out = device::SensorType::PROXIMITY;
+      return true;
+    case device::mojom::SensorType::ACCELEROMETER:
+      *out = device::SensorType::ACCELEROMETER;
+      return true;
+    case device::mojom::SensorType::GYROSCOPE:
+      *out = device::SensorType::GYROSCOPE;
+      return true;
+    case device::mojom::SensorType::PRESSURE:
+      *out = device::SensorType::PRESSURE;
+      return true;
+  }

[timvolodine, 2016/07/04 11:32:46]

NOTREACHED?

[shalamov, 2016/07/04 12:11:46]

Thanks, missed that.

+  return false;
+}
+
+}  // namespace mojo