gsocket.cpp

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  assert(this);

  /* must not be in use */
  if (m_fd != INVALID_SOCKET)
  {
    m_error = GSOCK_INVSOCK;
    return GSOCK_INVSOCK;
  }

  /* the local addr must have been set */
  if (!m_local)
  {
    m_error = GSOCK_INVADDR;
    return GSOCK_INVADDR;
  }

  /* Initialize all fields */
  m_stream   = true;
  m_server   = true;

  /* Create the socket */
  m_fd = socket(m_local->m_realfamily, SOCK_STREAM, 0);

  if (m_fd == INVALID_SOCKET)
  {
    m_error = GSOCK_IOERR;
    return GSOCK_IOERR;
  }

  /* FreeBSD variants can't use MSG_NOSIGNAL, and instead use a socket option */
#ifdef SO_NOSIGPIPE
  setsockopt(m_fd, SOL_SOCKET, SO_NOSIGPIPE, (const char*)&arg, sizeof(u_long));
#endif

  ioctl(m_fd, FIONBIO, &arg);
  gs_gui_functions->Enable_Events(this);

  /* allow a socket to re-bind if the socket is in the TIME_WAIT
     state after being previously closed.
   */
  if (m_reusable)
    setsockopt(m_fd, SOL_SOCKET, SO_REUSEADDR, (const char*)&arg, sizeof(u_long));

  /* Bind to the local address,
   * retrieve the actual address bound,
   * and listen up to 5 connections.
   */
  if ((bind(m_fd, m_local->m_addr, m_local->m_len) != 0) ||
      (getsockname(m_fd,
                   m_local->m_addr,
                   (WX_SOCKLEN_T *) &m_local->m_len) != 0) ||
      (listen(m_fd, 5) != 0))
  {
    Close();
    m_error = GSOCK_IOERR;
    return GSOCK_IOERR;
  }

  return GSOCK_NOERROR;
}

/* GSocket_WaitConnection:
 *  Waits for an incoming client connection. Returns a pointer to
 *  a GSocket object, or NULL if there was an error, in which case
 *  the last error field will be updated for the calling GSocket.
 *
 *  Error codes (set in the calling GSocket)
 *    GSOCK_INVSOCK    - the socket is not valid or not a server.
 *    GSOCK_TIMEDOUT   - timeout, no incoming connections.
 *    GSOCK_WOULDBLOCK - the call would block and the socket is nonblocking.
 *    GSOCK_MEMERR     - couldn't allocate memory.
 *    GSOCK_IOERR      - low-level error.
 */
GSocket *GSocket::WaitConnection()
{
  struct sockaddr from;
  WX_SOCKLEN_T fromlen = sizeof(from);
  GSocket *connection;
  GSocketError err;
  int arg = 1;

  assert(this);

  /* If the socket has already been created, we exit immediately */
  if (m_fd == INVALID_SOCKET || !m_server)
  {
    m_error = GSOCK_INVSOCK;
    return NULL;
  }

  /* Create a GSocket object for the new connection */
  connection = GSocket_new();

  if (!connection)
  {
    m_error = GSOCK_MEMERR;
    return NULL;
  }

  /* Wait for a connection (with timeout) */
  if (Input_Timeout() == GSOCK_TIMEDOUT)
  {
    delete connection;
    /* m_error set by _GSocket_Input_Timeout */
    return NULL;
  }

  connection->m_fd = accept(m_fd, &from, (WX_SOCKLEN_T *) &fromlen);

  /* Reenable CONNECTION events */
  Enable(GSOCK_CONNECTION);

  if (connection->m_fd == INVALID_SOCKET)
  {
    if (errno == EWOULDBLOCK)
      m_error = GSOCK_WOULDBLOCK;
    else
      m_error = GSOCK_IOERR;

    delete connection;
    return NULL;
  }

  /* Initialize all fields */
  connection->m_server   = false;
  connection->m_stream   = true;

  /* Setup the peer address field */
  connection->m_peer = GAddress_new();
  if (!connection->m_peer)
  {
    delete connection;
    m_error = GSOCK_MEMERR;
    return NULL;
  }
  err = _GAddress_translate_from(connection->m_peer, &from, fromlen);
  if (err != GSOCK_NOERROR)
  {
    delete connection;
    m_error = err;
    return NULL;
  }
#if defined(__EMX__) || defined(__VISAGECPP__)
  ioctl(connection->m_fd, FIONBIO, (char*)&arg, sizeof(arg));
#else
  ioctl(connection->m_fd, FIONBIO, &arg);
#endif
  gs_gui_functions->Enable_Events(connection);

  return connection;
}

bool GSocket::SetReusable()
{
    /* socket must not be null, and must not be in use/already bound */
    if (this && m_fd == INVALID_SOCKET) {
        m_reusable = true;
        return true;
    }
    return false;
}

/* Client specific parts */

/* GSocket_Connect:
 *  For stream (connection oriented) sockets, GSocket_Connect() tries
 *  to establish a client connection to a server using the peer address
 *  as established with GSocket_SetPeer(). Returns GSOCK_NOERROR if the
 *  connection has been successfully established, or one of the error
 *  codes listed below. Note that for nonblocking sockets, a return
 *  value of GSOCK_WOULDBLOCK doesn't mean a failure. The connection
 *  request can be completed later; you should use GSocket_Select()
 *  to poll for GSOCK_CONNECTION | GSOCK_LOST, or wait for the
 *  corresponding asynchronous events.
 *
 *  For datagram (non connection oriented) sockets, GSocket_Connect()
 *  just sets the peer address established with GSocket_SetPeer() as
 *  default destination.
 *
 *  Error codes:
 *    GSOCK_INVSOCK    - the socket is in use or not valid.
 *    GSOCK_INVADDR    - the peer address has not been established.
 *    GSOCK_TIMEDOUT   - timeout, the connection failed.
 *    GSOCK_WOULDBLOCK - connection in progress (nonblocking sockets only)
 *    GSOCK_MEMERR     - couldn't allocate memory.
 *    GSOCK_IOERR      - low-level error.
 */
GSocketError GSocket::Connect(GSocketStream stream)
{
  int err, ret;
  int arg = 1;

  assert(this);

  /* Enable CONNECTION events (needed for nonblocking connections) */
  Enable(GSOCK_CONNECTION);

  if (m_fd != INVALID_SOCKET)
  {
    m_error = GSOCK_INVSOCK;
    return GSOCK_INVSOCK;
  }

  if (!m_peer)
  {
    m_error = GSOCK_INVADDR;
    return GSOCK_INVADDR;
  }

  /* Streamed or dgram socket? */
  m_stream   = (stream == GSOCK_STREAMED);
  m_server   = false;
  m_establishing = false;

  /* Create the socket */
  m_fd = socket(m_peer->m_realfamily,
                     m_stream? SOCK_STREAM : SOCK_DGRAM, 0);

  if (m_fd == INVALID_SOCKET)
  {
    m_error = GSOCK_IOERR;
    return GSOCK_IOERR;
  }

  /* FreeBSD variants can't use MSG_NOSIGNAL, and instead use a socket option */
#ifdef SO_NOSIGPIPE
  setsockopt(m_fd, SOL_SOCKET, SO_NOSIGPIPE, (const char*)&arg, sizeof(u_long));
#endif

#if defined(__EMX__) || defined(__VISAGECPP__)
  ioctl(m_fd, FIONBIO, (char*)&arg, sizeof(arg));
#else
  ioctl(m_fd, FIONBIO, &arg);
#endif

  /* Connect it to the peer address, with a timeout (see below) */
  ret = connect(m_fd, m_peer->m_addr, m_peer->m_len);

  /* We only call Enable_Events if we know we aren't shutting down the socket.
   * NB: Enable_Events needs to be called whether the socket is blocking or
   * non-blocking, it just shouldn't be called prior to knowing there is a
   * connection _if_ blocking sockets are being used.
   * If connect above returns 0, we are already connected and need to make the
   * call to Enable_Events now.  
   */
  
  if (m_non_blocking || ret == 0)
  {
    gs_gui_functions->Enable_Events(this);
  }

  if (ret == -1)
  {
    err = errno;

    /* If connect failed with EINPROGRESS and the GSocket object
     * is in blocking mode, we select() for the specified timeout
     * checking for writability to see if the connection request
     * completes.
     */
    if ((err == EINPROGRESS) && (!m_non_blocking))
    {
      if (Output_Timeout() == GSOCK_TIMEDOUT)
      {
        Close();
        /* m_error is set in _GSocket_Output_Timeout */
        return GSOCK_TIMEDOUT;
      }
      else
      {
        int error;
        SOCKOPTLEN_T len = sizeof(error);

        getsockopt(m_fd, SOL_SOCKET, SO_ERROR, (char*) &error, &len);

        gs_gui_functions->Enable_Events(this);

        if (!error)
          return GSOCK_NOERROR;
      }
    }

    /* If connect failed with EINPROGRESS and the GSocket object
     * is set to nonblocking, we set m_error to GSOCK_WOULDBLOCK
     * (and return GSOCK_WOULDBLOCK) but we don't close the socket;
     * this way if the connection completes, a GSOCK_CONNECTION
     * event will be generated, if enabled.
     */
    if ((err == EINPROGRESS) && (m_non_blocking))
    {
      m_establishing = true;
      m_error = GSOCK_WOULDBLOCK;
      return GSOCK_WOULDBLOCK;
    }

    /* If connect failed with an error other than EINPROGRESS,
     * then the call to GSocket_Connect has failed.
     */
    Close();
    m_error = GSOCK_IOERR;
    return GSOCK_IOERR;
  }

  return GSOCK_NOERROR;
}

/* Datagram sockets */

/* GSocket_SetNonOriented:
 *  Sets up this socket as a non-connection oriented (datagram) socket.
 *  Before using this function, the local address must have been set
 *  with GSocket_SetLocal(), or the call will fail. Returns GSOCK_NOERROR
 *  on success, or one of the following otherwise.
 *
 *  Error codes:
 *    GSOCK_INVSOCK - the socket is in use.
 *    GSOCK_INVADDR - the local address has not been set.
 *    GSOCK_IOERR   - low-level error.
 */
GSocketError GSocket::SetNonOriented()
{
  int arg = 1;

  assert(this);

  if (m_fd != INVALID_SOCKET)
  {
    m_error = GSOCK_INVSOCK;
    return GSOCK_INVSOCK;
  }

  if (!m_local)
  {
    m_error = GSOCK_INVADDR;
    return GSOCK_INVADDR;
  }

  /* Initialize all fields */
  m_stream   = false;
  m_server   = false;

  /* Create the socket */
  m_fd = socket(m_local->m_realfamily, SOCK_DGRAM, 0);

  if (m_fd == INVALID_SOCKET)
  {
    m_error = GSOCK_IOERR;
    return GSOCK_IOERR;
  }
#if defined(__EMX__) || defined(__VISAGECPP__)
  ioctl(m_fd, FIONBIO, (char*)&arg, sizeof(arg));
#else
  ioctl(m_fd, FIONBIO, &arg);
#endif
  gs_gui_functions->Enable_Events(this);

  /* Bind to the local address,
   * and retrieve the actual address bound.
   */
  if ((bind(m_fd, m_local->m_addr, m_local->m_len) != 0) ||
      (getsockname(m_fd,
                   m_local->m_addr,
                   (WX_SOCKLEN_T *) &m_local->m_len) != 0))
  {
    Close();
    m_error = GSOCK_IOERR;
    return GSOCK_IOERR;
  }

  return GSOCK_NOERROR;
}

/* Generic IO */

/* Like recv(), send(), ... */
int GSocket::Read(char *buffer, int size)
{
  int ret;

  assert(this);

  if (m_fd == INVALID_SOCKET || m_server)
  {
    m_error = GSOCK_INVSOCK;
    return -1;
  }

  /* Disable events during query of socket status */
  Disable(GSOCK_INPUT);

  /* If the socket is blocking, wait for data (with a timeout) */
  if (Input_Timeout() == GSOCK_TIMEDOUT)
    /* We no longer return here immediately, otherwise socket events would not be re-enabled! */
    ret = -1;
  else {
    /* Read the data */
    if (m_stream)
      ret = Recv_Stream(buffer, size);
    else
      ret = Recv_Dgram(buffer, size);
  }

  /* If recv returned zero, then the connection is lost, and errno is not set.
   * Otherwise, recv has returned an error (-1), in which case we have lost the
   * socket only if errno does _not_ indicate that there may be more data to read.
   */
  if (ret == 0)
    m_error = GSOCK_IOERR;
  else if (ret == -1) {
    if ((errno == EWOULDBLOCK) || (errno == EAGAIN))
      m_error = GSOCK_WOULDBLOCK;
    else
      m_error = GSOCK_IOERR;
  }

  /* Enable events again now that we are done processing */
  Enable(GSOCK_INPUT);

  return ret;
}

int GSocket::Write(const char *buffer, int size)
{
  int ret;

  assert(this);

  GSocket_Debug(( "GSocket_Write #1, size %d\n", size ));

  if (m_fd == INVALID_SOCKET || m_server)
  {
    m_error = GSOCK_INVSOCK;
    return -1;
  }

  GSocket_Debug(( "GSocket_Write #2, size %d\n", size ));

  /* If the socket is blocking, wait for writability (with a timeout) */
  if (Output_Timeout() == GSOCK_TIMEDOUT)
    return -1;

  GSocket_Debug(( "GSocket_Write #3, size %d\n", size ));

  /* Write the data */
  if (m_stream)
    ret = Send_Stream(buffer, size);
  else
    ret = Send_Dgram(buffer, size);

  GSocket_Debug(( "GSocket_Write #4, size %d\n", size ));

  if (ret == -1)
  {
    if ((errno == EWOULDBLOCK) || (errno == EAGAIN))
    {
      m_error = GSOCK_WOULDBLOCK;
      GSocket_Debug(( "GSocket_Write error WOULDBLOCK\n" ));
    }
    else
    {
      m_error = GSOCK_IOERR;
      GSocket_Debug(( "GSocket_Write error IOERR\n" ));
    }

    /* Only reenable OUTPUT events after an error (just like WSAAsyncSelect
     * in MSW). Once the first OUTPUT event is received, users can assume
     * that the socket is writable until a read operation fails. Only then
     * will further OUTPUT events be posted.
     */
    Enable(GSOCK_OUTPUT);
    return -1;
  }

  GSocket_Debug(( "GSocket_Write #5, size %d ret %d\n", size, ret ));

  return ret;
}

/* GSocket_Select:
 *  Polls the socket to determine its status. This function will
 *  check for the events specified in the 'flags' parameter, and
 *  it will return a mask indicating which operations can be
 *  performed. This function won't block, regardless of the