basic_filebuf<_CharT, _Traits>*
basic_filebuf<_CharT, _Traits>::close() {
bool __ok = this->is_open();
if (_M_in_output_mode) {
__ok = __ok && !_Traits::eq_int_type(this->overflow(traits_type::eof()),
traits_type::eof());
__ok = __ok && this->_M_unshift();
}
else if (_M_in_input_mode)
this->_M_exit_input_mode();
// Note order of arguments. We close the file even if __ok is false.
__ok = _M_base._M_close() && __ok;
// Restore the initial state, except that we don't deallocate the buffer
// or mess with the cached codecvt information.
_M_state = _M_end_state = _State_type();
_M_ext_buf_converted = _M_ext_buf_end = 0;
_M_mmap_base = 0;
_M_mmap_len = 0;
this->setg(0, 0, 0);
this->setp(0, 0);
_M_saved_eback = _M_saved_gptr = _M_saved_egptr = 0;
_M_in_input_mode = _M_in_output_mode = _M_in_error_mode = _M_in_putback_mode
= false;
return __ok ? this : 0;
}
bool basic_filebuf<_CharT, _Traits>::_M_switch_to_output_mode() {
if (this->is_open() && (_M_base.__o_mode() & (int)ios_base::out) &&
_M_in_input_mode == 0 && _M_in_error_mode == 0) {
if (!_M_int_buf && !_M_allocate_buffers())
return false;
// In append mode, every write does an implicit seek to the end
// of the file. Whenever leaving output mode, the end of file
// get put in the initial shift state.
if (_M_base.__o_mode() & ios_base::app)
_M_state = _State_type();
this->setp(_M_int_buf, _M_int_buf_EOS - 1);
_M_in_output_mode = true;
return true;
}
return false;
}
