gecko-dev/ipc/unixsocket/UnixSocketConnector.h

/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_ipc_unixsocketconnector_h
#define mozilla_ipc_unixsocketconnector_h

#include <sys/socket.h>
#include "mozilla/ipc/UnixSocketWatcher.h"
#include "nsString.h"

namespace mozilla {
namespace ipc {

/**
 * |UnixSocketConnector| defines the socket creation and connection/listening
 * functions for |UnixSocketConsumer|, et al. Due to the fact that socket setup
 * can vary between protocols (Unix sockets, TCP sockets, Bluetooth sockets, etc),
 * this allows the user to create whatever connection mechanism they need while
 * still depending on libevent for non-blocking communication handling.
 */
class UnixSocketConnector
{
public:
  virtual ~UnixSocketConnector();

  /**
   * Converts an address to a human-readable string.
   *
   * @param aAddress A socket address
   * @param aAddressLength The number of valid bytes in |aAddress|
   * @param[out] aAddressString The resulting string
   * @return NS_OK on success, or an XPCOM error code otherwise.
   */
  virtual nsresult ConvertAddressToString(const struct sockaddr& aAddress,
                                          socklen_t aAddressLength,
                                          nsACString& aAddressString) = 0;

  /**
   * Creates a listening socket. I/O thread only.
   *
   * @param[out] aAddress The listening socket's address
   * @param[out] aAddressLength The number of valid bytes in |aAddress|
   * @param[out] aListenFd The socket's file descriptor
   * @return NS_OK on success, or an XPCOM error code otherwise.
   */
  virtual nsresult CreateListenSocket(struct sockaddr* aAddress,
                                      socklen_t* aAddressLength,
                                      int& aListenFd) = 0;

  /**
   * Accepts a stream socket from a listening socket. I/O thread only.
   *
   * @param aListenFd The listening socket
   * @param[out] aAddress Returns the stream socket's address
   * @param[out] aAddressLength Returns the number of valid bytes in |aAddress|
   * @param[out] aStreamFd The stream socket's file descriptor
   * @return NS_OK on success, or an XPCOM error code otherwise.
   */
  virtual nsresult AcceptStreamSocket(int aListenFd,
                                      struct sockaddr* aAddress,
                                      socklen_t* aAddressLen,
                                      int& aStreamFd) = 0;

  /**
   * Creates a stream socket. I/O thread only.
   *
   * @param[in|out] aAddress The stream socket's address
   * @param[in|out] aAddressLength The number of valid bytes in |aAddress|
   * @param[out] aStreamFd The socket's file descriptor
   * @return NS_OK on success, or an XPCOM error code otherwise.
   */
  virtual nsresult CreateStreamSocket(struct sockaddr* aAddress,
                                      socklen_t* aAddressLength,
                                      int& aStreamFd) = 0;

  /**
   * Copies the instance of |UnixSocketConnector|. I/O thread only.
   *
   * @param[in] aConnector Returns a new instance of the connector class
   * @return NS_OK on success, or an XPCOM error code otherwise
   */
  virtual nsresult Duplicate(UnixSocketConnector*& aConnector) = 0;

  /**
   * Copies the instance of |UnixSocketConnector|. I/O thread only.
   *
   * @param[in] aConnector Returns a new instance of the connector class
   * @return NS_OK on success, or an XPCOM error code otherwise
   */
  nsresult Duplicate(UniquePtr<UnixSocketConnector>& aConnector);

protected:
  UnixSocketConnector();
};

}
}

#endif