Method OpenTableFile

storage/connect/filamfix.cpp:814–970

/ OpenTableFile: opens a huge file using Windows/Unix API's. */ /

/*  OpenTableFile: opens a huge file using Windows/Unix API's.         */
/***********************************************************************/
bool BGXFAM::OpenTableFile(PGLOBAL g)
  {
  char    filename[_MAX_PATH];
  MODE    mode = Tdbp->GetMode();
  PDBUSER dbuserp = PlgGetUser(g);

  if ((To_Fb && To_Fb->Count) || Hfile != INVALID_HANDLE_VALUE) {
    snprintf(g->Message, sizeof(g->Message), MSG(FILE_OPEN_YET), To_File);
    return true;
    } // endif

  PlugSetPath(filename, To_File, Tdbp->GetPath());

  if (trace(1))
    htrc("OpenTableFile: filename=%s mode=%d\n", filename, mode);

#if defined(_WIN32)
  DWORD rc, access, creation, share = 0;

  /*********************************************************************/
  /*  Create the file object according to access mode                  */
  /*********************************************************************/
  switch (mode) {
    case MODE_READ:
      access = GENERIC_READ;
      share = FILE_SHARE_READ;
      creation = OPEN_EXISTING;
      break;
    case MODE_DELETE:
      if (!Tdbp->GetNext()) {
        // Store the number of deleted rows
        DelRows = Cardinality(g);

        // This will delete the whole file and provoque ReadDB to
        // return immediately.
        access = GENERIC_READ | GENERIC_WRITE;
        creation = TRUNCATE_EXISTING;
        Tdbp->ResetSize();
        Headlen = 0;
        break;
        } // endif

      // Selective delete, pass thru
    case MODE_UPDATE:
      if ((UseTemp = Tdbp->IsUsingTemp(g)))
        access = GENERIC_READ;
      else
        access = GENERIC_READ | GENERIC_WRITE;

      creation = OPEN_EXISTING;
      break;
    case MODE_INSERT:
      access = GENERIC_WRITE;
      creation = OPEN_ALWAYS;
      break;
    default:
      snprintf(g->Message, sizeof(g->Message), MSG(BAD_OPEN_MODE), mode);
      return true;