cfsocket.cpp

Wxpython Implemented on Windows CE, Source code

    {
      if ( !(m_flags & wxSOCKET_BLOCK) && !WaitForWrite() )
        break;

      ret = GSocket_Write(m_socket, (const char *)buffer, nbytes);

      if (ret > 0)
      {
        total  += ret;
        nbytes -= ret;
        buffer  = (const char *)buffer + ret;
      }

      // If we got here and wxSOCKET_WAITALL is not set, we can leave
      // now. Otherwise, wait until we send all the data or until there
      // is an error.
      //
      more = (ret > 0 && nbytes > 0 && (m_flags & wxSOCKET_WAITALL));
    }
  }

  return total;
}

wxSocketBase& wxSocketBase::WriteMsg(const void *buffer, wxUint32 nbytes)
{
  wxUint32 total;
  bool error;
  struct
  {
    unsigned char sig[4];
    unsigned char len[4];
  }
  msg;

  // Mask write events
  m_writing = true;

  error = true;
  total = 0;
  SetFlags((m_flags & wxSOCKET_BLOCK) | wxSOCKET_WAITALL);

  msg.sig[0] = (unsigned char) 0xad;
  msg.sig[1] = (unsigned char) 0xde;
  msg.sig[2] = (unsigned char) 0xed;
  msg.sig[3] = (unsigned char) 0xfe;

  msg.len[0] = (unsigned char) (nbytes & 0xff);
  msg.len[1] = (unsigned char) ((nbytes >> 8) & 0xff);
  msg.len[2] = (unsigned char) ((nbytes >> 16) & 0xff);
  msg.len[3] = (unsigned char) ((nbytes >> 24) & 0xff);

  if (_Write(&msg, sizeof(msg)) < sizeof(msg))
    goto exit;

  total = _Write(buffer, nbytes);

  if (total < nbytes)
    goto exit;

  msg.sig[0] = (unsigned char) 0xed;
  msg.sig[1] = (unsigned char) 0xfe;
  msg.sig[2] = (unsigned char) 0xad;
  msg.sig[3] = (unsigned char) 0xde;
  msg.len[0] = msg.len[1] = msg.len[2] = msg.len[3] = (char) 0;

  if ((_Write(&msg, sizeof(msg))) < sizeof(msg))
    goto exit;

  // everything was OK
  error = false;

exit:
  m_error = error;
  m_lcount = total;
  m_writing = false;

  return *this;
}

wxSocketBase& wxSocketBase::Unread(const void *buffer, wxUint32 nbytes)
{
  if (nbytes != 0)
    Pushback(buffer, nbytes);

  m_error = false;
  m_lcount = nbytes;

  return *this;
}

wxSocketBase& wxSocketBase::Discard()
{
  char *buffer = new char[MAX_DISCARD_SIZE];
  wxUint32 ret;
  wxUint32 total = 0;

  // Mask read events
  m_reading = true;

  SetFlags(wxSOCKET_NOWAIT);

  do
  {
    ret = _Read(buffer, MAX_DISCARD_SIZE);
    total += ret;
  }
  while (ret == MAX_DISCARD_SIZE);

  delete[] buffer;
  m_lcount = total;
  m_error  = false;

  // Allow read events again
  m_reading = false;

  return *this;
}

// --------------------------------------------------------------------------
// Wait functions
// --------------------------------------------------------------------------

// All Wait functions poll the socket using GSocket_Select() to
// check for the specified combination of conditions, until one
// of these conditions become true, an error occurs, or the
// timeout elapses. The polling loop calls PROCESS_EVENTS(), so
// this won't block the GUI.

bool wxSocketBase::_Wait(long seconds,
                         long milliseconds,
                         wxSocketEventFlags flags)
{
  GSocketEventFlags result;
  long timeout;

  // Set this to true to interrupt ongoing waits
  m_interrupt = false;

  // Check for valid socket
  if (!m_socket)
    return false;

  // Check for valid timeout value.
  if (seconds != -1)
    timeout = seconds * 1000 + milliseconds;
  else
    timeout = m_timeout * 1000;

#if !defined(wxUSE_GUI) || !wxUSE_GUI
  GSocket_SetTimeout(m_socket, timeout);
#endif

  // Wait in an active polling loop.
  //
  // NOTE: We duplicate some of the code in OnRequest, but this doesn't
  //   hurt. It has to be here because the (GSocket) event might arrive
  //   a bit delayed, and it has to be in OnRequest as well because we
  //   don't know whether the Wait functions are being used.
  //
  // Do this at least once (important if timeout == 0, when
  // we are just polling). Also, if just polling, do not yield.

  wxStopWatch chrono;
  bool done = false;

  while (!done)
  {
    result = GSocket_Select(m_socket, flags | GSOCK_LOST_FLAG);

    // Incoming connection (server) or connection established (client)
    if (result & GSOCK_CONNECTION_FLAG)
    {
      m_connected = true;
      m_establishing = false;

      return true;
    }

    // Data available or output buffer ready
    if ((result & GSOCK_INPUT_FLAG) || (result & GSOCK_OUTPUT_FLAG))
    {
      return true;
    }

    // Connection lost
    if (result & GSOCK_LOST_FLAG)
    {
      m_connected = false;
      m_establishing = false;

      return (flags & GSOCK_LOST_FLAG) != 0;
    }

    // Wait more?
    if ((!timeout) || (chrono.Time() > timeout) || (m_interrupt))
      done = true;
    else
      PROCESS_EVENTS();
  }

  return false;
}

bool wxSocketBase::Wait(long seconds, long milliseconds)
{
  return _Wait(seconds, milliseconds, GSOCK_INPUT_FLAG |
                                      GSOCK_OUTPUT_FLAG |
                                      GSOCK_CONNECTION_FLAG |
                                      GSOCK_LOST_FLAG);
}

bool wxSocketBase::WaitForRead(long seconds, long milliseconds)
{
  // Check pushback buffer before entering _Wait
  if (m_unread)
    return true;

  // Note that GSOCK_INPUT_LOST has to be explicitly passed to
  // _Wait becuase of the semantics of WaitForRead: a return
  // value of true means that a GSocket_Read call will return
  // immediately, not that there is actually data to read.

  return _Wait(seconds, milliseconds, GSOCK_INPUT_FLAG | GSOCK_LOST_FLAG);
}

bool wxSocketBase::WaitForWrite(long seconds, long milliseconds)
{
  return _Wait(seconds, milliseconds, GSOCK_OUTPUT_FLAG);
}

bool wxSocketBase::WaitForLost(long seconds, long milliseconds)
{
  return _Wait(seconds, milliseconds, GSOCK_LOST_FLAG);
}

// --------------------------------------------------------------------------
// Miscellaneous
// --------------------------------------------------------------------------

//
// Get local or peer address
//

bool wxSocketBase::GetPeer(wxSockAddress& addr_man) const
{
  GAddress *peer;

  if (!m_socket)
    return false;

  peer = GSocket_GetPeer(m_socket);

    // copying a null address would just trigger an assert anyway

  if (!peer)
    return false;

  addr_man.SetAddress(peer);
  GAddress_destroy(peer);

  return true;
}

bool wxSocketBase::GetLocal(wxSockAddress& addr_man) const
{
#if 0
  GAddress *local;

  if (!m_socket)
    return false;

  local = GSocket_GetLocal(m_socket);
  addr_man.SetAddress(local);
  GAddress_destroy(local);
#endif

  return true;
}

//
// Save and restore socket state
//

void wxSocketBase::SaveState()
{
  wxSocketState *state;

  state = new wxSocketState();

  state->m_flags      = m_flags;
  state->m_notify     = m_notify;
  state->m_eventmask  = m_eventmask;
  state->m_clientData = m_clientData;

  m_states.Append(state);
}

void wxSocketBase::RestoreState()
{
  wxList::compatibility_iterator node;
  wxSocketState *state;

  node = m_states.GetLast();
  if (!node)
    return;

  state = (wxSocketState *)node->GetData();

  m_flags      = state->m_flags;
  m_notify     = state->m_notify;
  m_eventmask  = state->m_eventmask;
  m_clientData = state->m_clientData;

  m_states.Erase(node);
  delete state;
}

//
// Timeout and flags
//

void wxSocketBase::SetTimeout(long seconds)
{
  m_timeout = seconds;

#if 0
  if (m_socket)
    GSocket_SetTimeout(m_socket, m_timeout * 1000);
#endif
}

void wxSocketBase::SetFlags(wxSocketFlags flags)
{
  m_flags = flags;
}


// --------------------------------------------------------------------------
// Event handling
// --------------------------------------------------------------------------

// A note on how events are processed, which is probably the most
// difficult thing to get working right while keeping the same API
// and functionality for all platforms.
//
// When GSocket detects an event, it calls wx_socket_callback, which in
// turn just calls wxSocketBase::OnRequest in the corresponding wxSocket
// object. OnRequest does some housekeeping, and if the event is to be
// propagated to the user, it creates a new wxSocketEvent object and
// posts it. The event is not processed immediately, but delayed with
// AddPendingEvent instead. This is necessary in order to decouple the
// event processing from wx_socket_callback; otherwise, subsequent IO
// calls made from the user event handler would fail, as gtk callbacks
// are not reentrant.
//
// Note that, unlike events, user callbacks (now deprecated) are _not_
// decoupled from wx_socket_callback and thus they suffer from a variety
// of problems. Avoid them where possible and use events instead.

extern "C"
void LINKAGEMODE wx_socket_callback(GSocket * WXUNUSED(socket),
                                    GSocketEvent notification,
                                    char *cdata)
{
  wxSocketBase *sckobj = (wxSocketBase *)cdata;

  sckobj->OnRequest((wxSocketNotify) notification);
}

void wxSocketBase::OnRequest(wxSocketNotify notification)
{
  // NOTE: We duplicate some of the code in _Wait, but this doesn't
  // hurt. It has to be here because the (GSocket) event might arrive
  // a bit delayed, and it has to be in _Wait as well because we don't
  // know whether the Wait functions are being used.

  switch (notification)
  {
    case wxSOCKET_CONNECTION:
      m_establishing = false;
      m_connected = true;
      break;

    // If we are in the middle of a R/W operation, do not
    // propagate events to users. Also, filter 'late' events
    // which are no longer valid.

    case wxSOCKET_INPUT:
      if (m_reading || !GSocket_Select(m_socket, GSOCK_INPUT_FLAG))
        return;
      break;

    case wxSOCKET_OUTPUT:
      if (m_writing || !GSocket_Select(m_socket, GSOCK_OUTPUT_FLAG))
        return;
      break;

    case wxSOCKET_LOST:
      m_connected = false;
      m_establishing = false;
      break;

    default:
      break;
  }

  // Schedule the event

  wxSocketEventFlags flag = 0;
  wxUnusedVar(flag);
  switch (notification)
  {
    case GSOCK_INPUT:
      flag = GSOCK_INPUT_FLAG;
      break;

    case GSOCK_OUTPUT:
      flag = GSOCK_OUTPUT_FLAG;
      break;

    case GSOCK_CONNECTION:
      flag = GSOCK_CONNECTION_FLAG;
      break;

    case GSOCK_LOST:
      flag = GSOCK_LOST_FLAG;
      break;

    default:
      wxLogWarning( wxT("wxSocket: unknown event!") );
      return;
  }

  if (((m_eventmask & flag) == flag) && m_notify)
  {
    if (m_handler)
    {
      wxSocketEvent event(m_id);
      event.m_event      = notification;
      event.m_clientData = m_clientData;
      event.SetEventObject(this);

      m_handler->AddPendingEvent(event);
    }
  }
}

void wxSocketBase::Notify(bool notify)
{
  m_notify = notify;
}

void wxSocketBase::SetNotify(wxSocketEventFlags flags)
{
  m_eventmask = flags;
}

void wxSocketBase::SetEventHandler(wxEvtHandler& handler, int id)
{
  m_handler = &handler;
  m_id      = id;
}

// --------------------------------------------------------------------------
// Pushback buffer
// --------------------------------------------------------------------------

void wxSocketBase::Pushback(const void *buffer, wxUint32 size)
{
  if (!size)
    return;

  if (m_unread == NULL)
    m_unread = malloc(size);
  else
  {
    void *tmp;

    tmp = malloc(m_unrd_size + size);
    memcpy((char *)tmp + size, m_unread, m_unrd_size);
    free(m_unread);

    m_unread = tmp;
  }

  m_unrd_size += size;

  memcpy(m_unread, buffer, size);
}

wxUint32 wxSocketBase::GetPushback(void *buffer, wxUint32 size, bool peek)
{
  if (!m_unrd_size)
    return 0;

  if (size > (m_unrd_size-m_unrd_cur))
    size = m_unrd_size-m_unrd_cur;

  memcpy(buffer, (char *)m_unread + m_unrd_cur, size);

  if (!peek)
  {
    m_unrd_cur += size;
    if (m_unrd_size == m_unrd_cur)
    {
      free(m_unread);
      m_unread = NULL;
      m_unrd_size = 0;
      m_unrd_cur  = 0;
    }
  }

  return size;
}


// ==========================================================================
// wxSocketServer
// ==========================================================================

// --------------------------------------------------------------------------
// Ctor
// --------------------------------------------------------------------------

wxSocketServer::wxSocketServer(wxSockAddress& addr_man,
                               wxSocketFlags flags)
              : wxSocketBase(flags, wxSOCKET_SERVER)
{
    wxLogTrace( wxTRACE_Socket, wxT("Opening wxSocketServer") );

    m_socket = GSocket_new();

    if (!m_socket)
    {
        wxLogTrace( wxTRACE_Socket, wxT("*** GSocket_new failed") );
        return;
    }

    // Setup the socket as server

#if 0
    GSocket_SetLocal(m_socket, addr_man.GetAddress());
    if (GSocket_SetServer(m_socket) != GSOCK_NOERROR)
    {
        GSocket_destroy(m_socket);
        m_socket = NULL;

        wxLogTrace( wxTRACE_Socket, wxT("*** GSocket_SetServer failed") );
        return;
    }

    GSocket_SetTimeout(m_socket, m_timeout * 1000);
    GSocket_SetCallback(m_socket, GSOCK_INPUT_FLAG | GSOCK_OUTPUT_FLAG |
                                  GSOCK_LOST_FLAG | GSOCK_CONNECTION_FLAG,
                                  wx_socket_callback, (char *)this);
#endif
}

// --------------------------------------------------------------------------
// Accept
// --------------------------------------------------------------------------

bool wxSocketServer::AcceptWith(wxSocketBase& sock, bool wait)
{
  GSocket *child_socket;

  if (!m_socket)
    return false;

  // If wait == false, then the call should be nonblocking.
  // When we are finished, we put the socket to blocking mode
  // again.

#if 0
  if (!wait)
    GSocket_SetNonBlocking(m_socket, 1);