message: ODBC: testing null string_length_ptr in SQLGetInfo.
diff: @@ -69,11 +69,20 @@ SQLRETURN SQLGetInfo(SQLHDBC connection_handle, SQLUSMALLINT info_type, SQLPOINT
  SQLFreeHandle(SQL_HANDLE_STMT, stmt);
  return SQL_ERROR;
  }
  - if (!SQL_SUCCEEDED(
  - SQLGetData(stmt, 1, SQL_C_CHAR, info_value_ptr, buffer_length, (SQLLEN *)string_length_ptr))) {
  +
  + SQLRETURN ret;
  + if (string_length_ptr) {
  + SQLLEN len_ptr;
  + ret = SQLGetData(stmt, 1, SQL_C_CHAR, info_value_ptr, buffer_length, &len_ptr);
  + *string_length_ptr = len_ptr;
  + } else {
  + ret = SQLGetData(stmt, 1, SQL_C_CHAR, info_value_ptr, buffer_length, NULL);
  + }
  + if (!SQL_SUCCEEDED(ret)) {
  SQLFreeHandle(SQL_HANDLE_STMT, stmt);
  return SQL_ERROR;
  }
  +
  SQLFreeHandle(SQL_HANDLE_STMT, stmt);
  return SQL_SUCCESS;
  }
  