bluetooth: Return int8_t and use -128 for unknown tx power.

device/bluetooth/bluez/bluetooth_device_bluez.cc

 // Copyright 2013 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/bluetooth/bluez/bluetooth_device_bluez.h"
 
 #include <stdio.h>
 
 #include <memory>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
+#include "base/optional.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "dbus/bus.h"
 #include "device/bluetooth/bluetooth_socket.h"
 #include "device/bluetooth/bluetooth_socket_thread.h"
 #include "device/bluetooth/bluetooth_uuid.h"
 #include "device/bluetooth/bluez/bluetooth_adapter_bluez.h"
 #include "device/bluetooth/bluez/bluetooth_gatt_connection_bluez.h"
 #include "device/bluetooth/bluez/bluetooth_pairing_bluez.h"
 #include "device/bluetooth/bluez/bluetooth_remote_gatt_service_bluez.h"
@@ skipping 106 matching lines @@
   } else if (error_name == bluetooth_device::kErrorAuthenticationCanceled) {
     error_code = BluetoothDevice::ERROR_AUTH_CANCELED;
   } else if (error_name == bluetooth_device::kErrorAuthenticationRejected) {
     error_code = BluetoothDevice::ERROR_AUTH_REJECTED;
   } else if (error_name == bluetooth_device::kErrorAuthenticationTimeout) {
     error_code = BluetoothDevice::ERROR_AUTH_TIMEOUT;
   }
   return error_code;
 }
 
+base::Optional<int8_t> EnsureValidPower(int16_t power) {
+  return ((power < INT8_MIN) || (power > INT8_MAX)) ? base::Optional<int8_t>()
+                                                    : power;
+}
+
 }  // namespace
 
 namespace bluez {
 
 BluetoothDeviceBlueZ::BluetoothDeviceBlueZ(
     BluetoothAdapterBlueZ* adapter,
     const dbus::ObjectPath& object_path,
     scoped_refptr<base::SequencedTaskRunner> ui_task_runner,
     scoped_refptr<device::BluetoothSocketThread> socket_thread)
     : BluetoothDevice(adapter),
@@ skipping 159 matching lines @@
   const std::vector<std::string>& dbus_uuids = properties->uuids.value();
   for (std::vector<std::string>::const_iterator iter = dbus_uuids.begin();
        iter != dbus_uuids.end(); ++iter) {
     device::BluetoothUUID uuid(*iter);
     DCHECK(uuid.IsValid());
     uuids.push_back(uuid);
   }
   return uuids;
 }
 
-int16_t BluetoothDeviceBlueZ::GetInquiryRSSI() const {
+base::Optional<int8_t> BluetoothDeviceBlueZ::GetInquiryRSSI() const {
   bluez::BluetoothDeviceClient::Properties* properties =
       bluez::BluezDBusManager::Get()->GetBluetoothDeviceClient()->GetProperties(
           object_path_);
   DCHECK(properties);
 
   if (!properties->rssi.is_valid())
-    return kUnknownPower;
+    return base::Optional<int8_t>();
 
-  return properties->rssi.value();
+  return EnsureValidPower(properties->rssi.value());
 }
 
-int16_t BluetoothDeviceBlueZ::GetInquiryTxPower() const {
+base::Optional<int8_t> BluetoothDeviceBlueZ::GetInquiryTxPower() const {
   bluez::BluetoothDeviceClient::Properties* properties =
       bluez::BluezDBusManager::Get()->GetBluetoothDeviceClient()->GetProperties(
           object_path_);
   DCHECK(properties);
 
   if (!properties->tx_power.is_valid())
-    return kUnknownPower;
+    return base::Optional<int8_t>();
 
-  return properties->tx_power.value();
+  return EnsureValidPower(properties->tx_power.value());
 }
 
 bool BluetoothDeviceBlueZ::ExpectingPinCode() const {
   return pairing_.get() && pairing_->ExpectingPinCode();
 }
 
 bool BluetoothDeviceBlueZ::ExpectingPasskey() const {
   return pairing_.get() && pairing_->ExpectingPasskey();
 }
 
@@ skipping 236 matching lines @@
           << "' from device: " << GetAddress();
 
   DCHECK(service->object_path() == object_path);
   std::unique_ptr<BluetoothRemoteGattService> scoped_service =
       gatt_services_.take_and_erase(iter->first);
 
   DCHECK(adapter_);
   adapter()->NotifyGattServiceRemoved(service);
 }
 
-void BluetoothDeviceBlueZ::OnGetConnInfo(const ConnectionInfoCallback& callback,
-                                         int16_t rssi,
-                                         int16_t transmit_power,
-                                         int16_t max_transmit_power) {
-  callback.Run(ConnectionInfo(rssi, transmit_power, max_transmit_power));
+void BluetoothDeviceBlueZ::OnGetConnInfo(
+    const ConnectionInfoCallback& callback,
+    const base::Optional<int16_t>& rssi,
+    const base::Optional<int16_t>& transmit_power,
+    const base::Optional<int16_t>& max_transmit_power) {
+  if (!rssi) {
+    DCHECK(!transmit_power);
+    DCHECK(!max_transmit_power);
+    callback.Run(ConnectionInfo());
+  }
+
+  callback.Run(ConnectionInfo(EnsureValidPower(rssi.value()),
+                              EnsureValidPower(transmit_power.value()),
+                              EnsureValidPower(max_transmit_power.value())));
 }
 
 void BluetoothDeviceBlueZ::OnGetConnInfoError(
     const ConnectionInfoCallback& callback,
     const std::string& error_name,
     const std::string& error_message) {
   LOG(WARNING) << object_path_.value()
                << ": Failed to get connection info: " << error_name << ": "
                << error_message;
   callback.Run(ConnectionInfo());
@@ skipping 164 matching lines @@
 void BluetoothDeviceBlueZ::OnForgetError(const ErrorCallback& error_callback,
                                          const std::string& error_name,
                                          const std::string& error_message) {
   LOG(WARNING) << object_path_.value()
                << ": Failed to remove device: " << error_name << ": "
                << error_message;
   error_callback.Run();
 }
 
 }  // namespace bluez