Method GetXdef

storage/connect/reldef.cpp:612–733

/ GetXdef: get the external TABDEF from OEM module. */ /

/*  GetXdef: get the external TABDEF from OEM module.                  */
/***********************************************************************/
PTABDEF OEMDEF::GetXdef(PGLOBAL g)
  {
  typedef PTABDEF (__stdcall *XGETDEF) (PGLOBAL, void *);
  char    c, soname[_MAX_PATH], getname[40] = "Get";
  PTABDEF xdefp;
  XGETDEF getdef = NULL;
  PCATLG  cat = Cat;

  /*********************************************************************/
  /*  Ensure that the module name doesn't have a path.                 */
  /*  This is done to ensure that only approved libs from the system   */
  /*  directories are used (to make this even remotely secure).        */
  /*********************************************************************/
  if (check_valid_path(Module, strlen(Module))) {
    safe_strcpy(g->Message, sizeof(g->Message), "Module cannot contain a path");
    return NULL;
	}
	else if (strlen(Subtype)+1+3 >= sizeof(getname)) {
		safe_strcpy(g->Message, sizeof(g->Message), "Subtype string too long");
		return NULL;
	}
  else
//  PlugSetPath(soname, Module, GetPluginDir());  // Crashes on Fedora
    snprintf(soname, sizeof(soname), "%s%s", GetPluginDir(), Module);

#if defined(_WIN32)
  // Is the DLL already loaded?
  if (!Hdll && !(Hdll = GetModuleHandle(soname)))
    // No, load the Dll implementing the function
    if (!(Hdll = LoadLibrary(soname))) {
      char  buf[256];
      DWORD rc = GetLastError();

      snprintf(g->Message, sizeof(g->Message), MSG(DLL_LOAD_ERROR), rc, soname);
      FormatMessage(FORMAT_MESSAGE_FLAGS, NULL, rc, 0,
                    (LPTSTR)buf, sizeof(buf), NULL);
      safe_strcat(g->Message, sizeof(g->Message), ": ");
      safe_strcat(g->Message, sizeof(g->Message), buf);
      return NULL;
      } // endif hDll

  // The exported name is always in uppercase
  for (int i = 0; ; i++) {
    c = Subtype[i];
    getname[i + 3] = toupper(c);
    if (!c) break;
    } // endfor i

  // Get the function returning an instance of the external DEF class
  if (!(getdef = (XGETDEF)GetProcAddress((HINSTANCE)Hdll, getname))) {
    char  buf[256];
    DWORD rc = GetLastError();

    snprintf(g->Message, sizeof(g->Message), MSG(PROCADD_ERROR), rc, getname);
    FormatMessage(FORMAT_MESSAGE_FLAGS, NULL, rc, 0,
      (LPTSTR)buf, sizeof(buf), NULL);
    safe_strcat(g->Message, sizeof(g->Message), ": ");
    safe_strcat(g->Message, sizeof(g->Message), buf);