Embedding a Ruby Interpreter- working with struct

embeded_struct.c

struct Address {
	char * town;
};

struct Person {
	struct Address * address;
	char * name;
};

static VALUE wrap_person_get_address(VALUE self) {
	struct Person * person;
	Data_Get_Struct(self, struct Person, person);
	VALUE wrapped_address =Data_Wrap_Struct(address_wrapper_class, NULL, NULL, person->address);
	return wrapped_address;
}

...

	address_wrapper_class = rb_define_class("Address", rb_cObject);
	VALUE person_wrapper_class = rb_class_new(rb_cObject);

	/*
	 Add #town and #town= methods to the new class

	 Here we associate the two implementation functions defined above with the
	 wrapper class, so that in ruby it will respond to the methods #town and #town=
	 //    */
	rb_define_method(address_wrapper_class, "town", wrap_address_get_town, 0); //getter method: #town
	rb_define_method(address_wrapper_class, "town=", wrap_address_set_town, 1);//setter method: #town=

	rb_define_method(person_wrapper_class, "name", wrap_person_get_name, 0);
	rb_define_method(person_wrapper_class, "name=", wrap_person_set_name, 1);

	rb_define_method(person_wrapper_class, "address", wrap_person_get_address,
			0);

...

ruby_ext_test_api.c

/*
 ============================================================================
 Name        : rub_ext_test.c
 Author      : Matej
 Version     :
 Copyright   : 
 Description : Working version with struct defined and inicialized by Ruby C API
 ============================================================================
 */

#include <stdio.h>
#include <stdlib.h>

#include "ruby.h"

static int id_print_method;

static VALUE klass;

struct Address {
	char * town;
};

static VALUE wrap_print(VALUE args) {
	VALUE *values = (VALUE *) args;
	VALUE testClass = values[0];
	VALUE adr = values[1];

	return rb_funcall(testClass, id_print_method, 1, adr);
}

static VALUE protected_print(VALUE testClass, VALUE adr) {
	int error;
	VALUE args[2];
	VALUE result;

	args[0] = testClass;
	args[1] = adr;

	result = rb_protect(wrap_print, (VALUE) args, &error);

	return error ? Qnil : result;
}

int main(int argc, char **argv) {
	int error;

	struct Address adr;
	adr.town = "London";

	ruby_sysinit(&argc, &argv);
	RUBY_INIT_STACK;
	ruby_init();
	ruby_init_loadpath();
	ruby_script("demo_embedder"); /* sets name in error messages */

	rb_protect((VALUE(*)(VALUE)) rb_require, (VALUE) "test", &error);

	VALUE testClass = rb_class_new_instance(0, 0, rb_const_get(rb_cObject,
			rb_intern("TestKlass")));

	VALUE adr_ptr;
	adr_ptr = Data_Wrap_Struct(klass,0,0,&adr);

	VALUE adr_struct = rb_struct_define("Adresa","town" , 0);
	VALUE inst_adr_struct=rb_struct_new(adr_struct,1);


	rb_struct_aset(inst_adr_struct,rb_str_new2("town"),rb_str_new2("London"));
	id_print_method = rb_intern("print_info");

	//	VALUE result;
	//	VALUE result = protected_print(testClass, adr_ptr);
		VALUE result = protected_print(testClass, inst_adr_struct);

		if (NIL_P(result))
			printf("Nil!\n");
		else
			printf("Returned %d\n", NUM2INT(result));


	puts("FINISHED"); /* prints FINISHED */
	return ruby_cleanup(0);
}

ruby_ext_test_wrap.c

/*
 ============================================================================
 Name        : rub_ext_test.c
 Author      : Matej
 Version     :
 Copyright   : 
 Description : Wrapping struct (not working)
 ============================================================================
 */

#include <stdio.h>
#include <stdlib.h>

#include "ruby.h"

static int id_print_method;

static VALUE klass;

struct Address {
	char * town;
};

static VALUE wrap_print(VALUE args) {
	VALUE *values = (VALUE *) args;
	VALUE testClass = values[0];
	VALUE adr = values[1];

	return rb_funcall(testClass, id_print_method, 1, adr);
}

static VALUE protected_print(VALUE testClass, VALUE adr) {
	int error;
	VALUE args[2];
	VALUE result;

	args[0] = testClass;
	args[1] = adr;

	result = rb_protect(wrap_print, (VALUE)args, &error);

	return error ? Qnil : result;
}

int main(int argc, char **argv) {
	int error;


	struct Address adr;
	adr.town = "London";

	ruby_sysinit(&argc, &argv);
	RUBY_INIT_STACK;
	ruby_init();
	ruby_init_loadpath();
	ruby_script("demo_embedder"); /* sets name in error messages */

	rb_protect((VALUE(*)(VALUE)) rb_require, (VALUE) "test", &error);

	VALUE testClass = rb_class_new_instance(0, 0, rb_const_get(rb_cObject,
			rb_intern("TestKlass")));

	VALUE adr_ptr;
	adr_ptr = Data_Wrap_Struct(klass,0,0,&adr);

	id_print_method = rb_intern("print_info");

	VALUE result = protected_print(testClass, adr_ptr);

	if (NIL_P(result))
		printf("Nil!\n");
	else
		printf("Returned %d\n", NUM2INT(result));



	puts("FINISHED"); /* prints FINISHED */
	return ruby_cleanup(0);
}

test.rb

require 'test'

class TestKlass
  def print_info(struct)
  puts "In Ruby"
  puts struct.inspect
  puts struct.town
  return 0
  end
end