Factor out a BluetoothChannelMac base class and a BluetoothRfcommChannelMac subclass.

device/bluetooth/bluetooth_channel_mac.h

+// Copyright 2014 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_CHANNEL_MAC_H_
+#define DEVICE_BLUETOOTH_BLUETOOTH_CHANNEL_MAC_H_
+
+#import <IOKit/IOReturn.h>
+
+#include <string>
+
+#include "base/macros.h"
+
+namespace device {
+
+class BluetoothSocketMac;
+
+// Wraps a native RFCOMM or L2CAP channel.
+class BluetoothChannelMac {
+ public:
+  BluetoothChannelMac();
+  virtual ~BluetoothChannelMac();
+
+  // Sets the channel's owning socket to |socket|. Should only be called if the
+  // socket was previously unset. Note: This can synchronously call back into
+  // socket->OnChannelOpenComplete().
+  virtual void SetSocket(BluetoothSocketMac* socket);
+
+  // Returns the Bluetooth address for the device associated with |this|
+  // channel.
+  virtual std::string GetDeviceAddress() = 0;
+
+  // Returns the outgoing MTU (maximum transmission unit) for the channel.
+  virtual uint16_t GetOutgoingMTU() = 0;
+
+  // Writes |data| of length |length| bytes into the channel. The |refcon| is a
+  // user-supplied value that gets passed to the write callback.
+  // Returns kIOReturnSuccess if the data was buffered successfully.
+  // If the return value is an error condition none of the data was sent.
+  // The number of bytes to be sent must not exceed the channel MTU.
+  //
+  // Once the data has been successfully passed to the hardware to be
+  // transmitted, the socket's method OnChannelWriteComplete() will be called
+  // with the |refcon| that was passed to this method.
+  virtual IOReturn WriteAsync(void* data, uint16_t length, void* refcon) = 0;
+
+ protected:
+  BluetoothSocketMac* socket() { return socket_; }
+
+ private:
+  // The socket that owns |this|.
+  BluetoothSocketMac* socket_;
+
+  DISALLOW_COPY_AND_ASSIGN(BluetoothChannelMac);
+};
+
+}  // namespace device
+
+#endif  // DEVICE_BLUETOOTH_BLUETOOTH_CHANNEL_MAC_H_