Using swig to access pointers to pointers from C in python

Question

I have been having problems making swig work for the following:

In C i have:

typedef struct
{
  uint8_t a[16];
  uint8_t b;
  uint8_t c;
  uint8_t d;
  uint8_t e;
  uint8_t f;
}t_type2;

typedef struct
{
  uint8_t a[16];
  uint8_t b;
  uint8_t c;
  uint8_t d;
  t_type2 ch[10];
  uint8_t e;
}t_type1;

And i have a function that has prototype:

t_dtbt_uint8 test_func(t_type1 **types);

It return an array to an internal data buffer containing an array of "t_type1".

I can make a typedef that returns the services correctly so in python i can do:

err, types = test_wrap.test_func()

But i simply cannot get "types" to contain anything valid.

Anyone know how to do this?

I have looked at tons of other examples, but no matter what i do i end up in errors and crashes.

I have tried this without success:

%typemap(in, numinputs=0) t_type1 **types_result(t_type1 *temp) {$1= &temp;}
%typemap(argout) t_type1 **types 
{
  $result = SWIG_Python_AppendOutput ($result, SWIG_NewPointerObj(*$1, WIGTYPE_p_p_t_type1, 0 | 0 ));
}

and wrapper function:

uint8_t test_func_wrapper(t_type1 **types_result)
{
  int err = test_func(types_result);
  return err;
}

It compiles fine, but I simply cannot find the right combination to make it work. I use similar constructions for simpler types, but for this I cannot make it work.

As soon as i access the array in Python i get a sigfault, or a iteration error. I am sure there is a way to do this...

Thanks,

/pedro

Tried all examples i could find, but none seemed to work for my purpose.