bt/vendor_libs/test_vendor_lib/include/hci_transport.h

//
// Copyright 2015 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

#pragma once

#include <functional>
#include <list>
#include <memory>

#include "base/files/scoped_file.h"
#include "command_packet.h"
#include "event_packet.h"
#include "packet.h"
#include "packet_stream.h"

namespace test_vendor_lib {

// Manages communication channel between HCI and the controller by providing the
// socket mechanisms for sending HCI [commands|events] [to|from] the controller.
class HciTransport {
 public:
  HciTransport();

  virtual ~HciTransport() = default;

  void CloseHciFd();

  void CloseVendorFd();

  int GetHciFd() const;

  int GetVendorFd() const;

  // Creates the underlying socketpair to be used as a communication channel
  // between the HCI and the vendor library/controller. Returns false if an
  // error occurs.
  bool SetUp();

  // Sets the callback that is run when command packets are received.
  void RegisterCommandHandler(
      const std::function<void(std::unique_ptr<CommandPacket>)>& callback);

  // Blocks while it tries to writes the event to the vendor file descriptor.
  void SendEvent(std::unique_ptr<EventPacket> event);

  // Called when there is a command to read on |fd|.
  void OnCommandReady(int fd);

 private:
  // Callback executed in ReceiveReadyCommand() to pass the incoming command
  // over to the handler for further processing.
  std::function<void(std::unique_ptr<CommandPacket>)> command_handler_;

  // For performing packet-based IO.
  PacketStream packet_stream_;

  // The two ends of the socketpair. |hci_fd_| is handed back to the HCI in
  // bt_vendor.cc and |vendor_fd_| is used by |packet_stream_| to receive/send
  // data from/to the HCI. Both file descriptors are owned and managed by the
  // transport object, although |hci_fd_| can be closed by the HCI in
  // TestVendorOp().
  std::unique_ptr<base::ScopedFD> hci_fd_;
  std::unique_ptr<base::ScopedFD> vendor_fd_;

  HciTransport(const HciTransport& cmdPckt) = delete;
  HciTransport& operator=(const HciTransport& cmdPckt) = delete;
};

}  // namespace test_vendor_lib