Request for help with PIDL

[Kamen Mazdrashki]

On Thu, Apr 1, 2010 at 00:48, Jelmer Vernooij <jelmer at samba.org> wrote:

> On Wed, 2010-03-31 at 01:43 +0300, Kamen Mazdrashki wrote:
> > Hi guys,
> >
> > I am trying to create 'drsblobs' python module out of
> > "librpc/gen_ndr/py_drsblobs.c"
> > generated file. Unfortunately py_drsblobs.c does not compile :(
> >
> > Could you please take a look at py_drsblobs.c, line: 3305 to 3316
> > static int py_package_PrimaryKerberosString_set_string(PyObject *py_obj,
> > PyObject *value, void *closure)
> > {
> > struct package_PrimaryKerberosString *object = (struct
> > package_PrimaryKerberosString *)py_talloc_get_ptr(py_obj);
> > talloc_free(object->string);
> > if (value == Py_None) {
> > object->string = NULL;
> > } else {
> > object->string = talloc_ptrtype(py_talloc_get_mem_ctx(py_obj),
> > object->string);
> > *object->string = talloc_strdup(py_talloc_get_mem_ctx(py_obj),
> > PyString_AsString(value));
> > }
> > return 0;
> > }
> >
> > and "librpc/idl/drsblobs.idl" - line: 337 to 341
> > typedef struct {
> > [value(2*strlen_m(string))] uint16 length;
> > [value(2*strlen_m(string))] uint16 size;
> >
> [relative,subcontext(0),subcontext_size(size),flag(STR_NOTERM|NDR_REMAINING)]
> > string *string;
> > } package_PrimaryKerberosString;
> >
> >
> > What is wrong here?
> > Is it the PIDL's Python generator or the IDL definition?
> Either :-)
>
> There is a bit too much magic involved in the "string" variable type
> that the Python module can't handle without quite a bit of extra code.
> In this particular situation it eliminates an extra pointer.
>
> Ideally we should just replace the "string" variable type with the use
> of a normal char type.
>
>
I've tried to change the IDL description to this:
[
 relative,
 subcontext(0),
 subcontext_size(size),
 flag(STR_NOTERM|NDR_REMAINING),
 charset(UTF16),
 string,
 size_is(size/2)
 ] uint16 *string;
Unfortunately no luck (sorry to use the work "luck", but Perl magic looks
like a Chinese dialect to me).
When removing "subcontext(0),subcontext_size(size)" though, everything is
fine!
I mean 'fine' for Python code generated :)
Although, following generated look little bit strange:
object->string = talloc_ptrtype(py_talloc_get_mem_ctx(py_obj),
object->string);
PY_CHECK_TYPE(&PyUnicode_Type, value, return -1;);
object->string = PyString_AsString(PyUnicode_AsEncodedString(value, "utf-8",
"ignore"));
It leaves a memory leek, isn't it?

Anyway, for NDR code I guess it is the "subcontext" spell that makes it to
parse the blob
in format described at:
http://msdn.microsoft.com/en-us/library/cc245503(v=PROT.10).aspx

So, how should I change the definition (or the Python generator)?

-- 
CU,
Kamen Mazdrashki
kamen.mazdrashki at postpath.com
http://repo.or.cz/w/Samba/kamenim.git
-------------------------------------
CISCO SYSTEMS BULGARIA EOOD
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