Bluetooth: macOS: Implementing read/write for descriptors

device/bluetooth/bluetooth_remote_gatt_characteristic_mac.h

 // 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.
 
 #ifndef DEVICE_BLUETOOTH_BLUETOOTH_REMOTE_GATT_CHARACTERISTIC_MAC_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_REMOTE_GATT_CHARACTERISTIC_MAC_H_
 
 #include "device/bluetooth/bluetooth_remote_gatt_characteristic.h"
 
+#import <CoreBluetooth/CoreBluetooth.h>
 #include <unordered_map>
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/memory/weak_ptr.h"
 
-#if defined(__OBJC__)
-#import <CoreBluetooth/CoreBluetooth.h>
-#else
-@class CBCharacteristic;
-typedef NS_ENUM(NSInteger, CBCharacteristicWriteType);
-#endif  // defined(__OBJC__)
-
 namespace device {
 
 class BluetoothAdapterMac;
 class BluetoothRemoteGattDescriptorMac;
 class BluetoothRemoteGattServiceMac;
 
 // The BluetoothRemoteGattCharacteristicMac class implements
 // BluetoothRemoteGattCharacteristic for remote GATT services on OS X.
 class DEVICE_BLUETOOTH_EXPORT BluetoothRemoteGattCharacteristicMac
     : public BluetoothRemoteGattCharacteristic {
@@ skipping 27 matching lines @@
  protected:
   void SubscribeToNotifications(BluetoothRemoteGattDescriptor* ccc_descriptor,
                                 const base::Closure& callback,
                                 const ErrorCallback& error_callback) override;
   void UnsubscribeFromNotifications(
       BluetoothRemoteGattDescriptor* ccc_descriptor,
       const base::Closure& callback,
       const ErrorCallback& error_callback) override;
 
  private:
+  friend class BluetoothLowEnergyDeviceMac;
   friend class BluetoothRemoteGattDescriptorMac;
   friend class BluetoothRemoteGattServiceMac;
   friend class BluetoothTestMac;
 
   void DiscoverDescriptors();
   // Called by the BluetoothRemoteGattServiceMac instance when the
   // characteristics value has been read.
   void DidUpdateValue(NSError* error);
   // Updates value_.
   void UpdateValue();
@@ skipping 57 matching lines @@
 };
 
 // Stream operator for logging.
 DEVICE_BLUETOOTH_EXPORT std::ostream& operator<<(
     std::ostream& out,
     const BluetoothRemoteGattCharacteristicMac& characteristic);
 
 }  // namespace device
 
 #endif  // DEVICE_BLUETOOTH_BLUETOOTH_REMOTE_GATT_CHARACTERISTIC_MAC_H_