how to use ei_decode_term to decode. - c++

Question

I have a c++ code which receives data from an erlang process. I get a tuple and using ei_decode_tuple_header/4, I got the arity of the list and then using a for-loop to traverse through the elements of the tuple and decode each one of them like this:
void decode_tuple(char *buff) {
int index = 0;
int size;
int type;
int res = ei_decode_tuple_header(buff, &index, &size);
if(res == 0) {
cout<<"Success"<<endl;
} else {
cout<<"Fail"<<endl;
}
for(int i = 0; i < size; ++i) {
char *p = (char*)malloc(sizeof(char) * 1000);
int res = ei_decode_string(buff, &index, p);
if(res == 0) {
cout<<"Success"<<endl;
} else {
cout<<"Fail"<<endl;
}
cout<<"The decoded string is "<<p<<endl;
}
}
However, this works only fine when all of the elements in the tuple/list are of the same type. I would like to decode no matter what the term is. I know that there is ei_decode_term but the documentation is so bad that I could not get an idea as to how to do it?
Can some one help! thanks#

Answer 1

Have you tried with ei_decode_ei_term, something like:
void decode_tuple(char *buff) {
int index = 0;
int size;
int type;
int res = ei_decode_tuple_header(buff, &index, &size);
if(res == 0) {
cout << "Success" << endl;
} else {
cout << "Fail" << endl;
}
for(int i = 0; i < size; ++i) {
ei_term term;
int res = ei_decode_ei_term(buff, &index, &term);
if (res == 0) {
cout << "Success" << endl;
} else {
cout << "Fail" << endl;
}
cout << "The decoded data is " << term.value << endl;
}
}
The ei_term is defined like:
typedef struct {
char ei_type;
int arity;
int size;
union {
long i_val;
double d_val;
char atom_name[MAXATOMLEN_UTF8];
erlang_pid pid;
erlang_port port;
erlang_ref ref;
} value;
} ei_term;
So you may need to check term.ei_type for better parsing