Function PyWin_SetAPIError

win32/src/PyWinTypesmodule.cpp:287–323

error helper - GetLastError() is provided, but this is for exceptions */

/* error helper - GetLastError() is provided, but this is for exceptions */
PyObject *PyWin_SetAPIError(char *fnName, long err /*= 0*/)
{
	DWORD errorCode = err == 0 ? GetLastError() : err;
	DWORD flags = FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_ALLOCATE_BUFFER | \
	              FORMAT_MESSAGE_IGNORE_INSERTS;
	// try and find the hmodule providing this error.
	HMODULE hmodule = PyWin_GetErrorMessageModule(errorCode);
	if (hmodule)
		flags |= FORMAT_MESSAGE_FROM_HMODULE;
	TCHAR *buf = NULL;
	BOOL free_buf = TRUE;
	if (errorCode)
		::FormatMessage(flags, hmodule, errorCode, 0, (LPTSTR)&buf, 0, NULL );
	if (!buf) {
		buf = _T("No error message is available");
		free_buf = FALSE;
	}
	/* strip trailing cr/lf */
	size_t end = _tcslen(buf)-1;
	if (end>1 && (buf[end-1]==_T('\n') || buf[end-1]==_T('\r')))
		buf[end-1] = _T('\0');
	else
		if (end>0 && (buf[end]==_T('\n') || buf[end]==_T('\r')))
			buf[end]=_T('\0');

	PyObject *v = Py_BuildValue("(iNN)",
		errorCode,
		PyWinCoreString_FromString(fnName),
		PyWinObject_FromTCHAR(buf));
	if (free_buf && buf)
		LocalFree(buf);		
	if (v != NULL) {
		PyErr_SetObject(PyWinExc_ApiError, v);
		Py_DECREF(v);
	}
	return NULL;
}

// This function sets a basic COM error - it is a valid COM
// error, but may not contain rich error text about the error.