Decode makes my programme crash

[hanako-eo]

I use koffi in a project and I have a function this function (it's in rust) :

#[no_mangle]
pub extern "C" fn get_headers<'a>(req: *const Request<'a>) -> *const (*const c_char, *const c_char) {
    let req = unsafe { &*req };
    // CString is just a equivalent to &[u8] store in the heap
    req.headers().as_ptr() as *const (*const c_char, *const c_char)
}

in c my function is equivalent to

typedef struct TupleString2 {
    char *first;
    char *last;
} TupleString2;
TupleString2 *get_headers(Request *req);

but want I try to do :

const StringTuple2 = koffi.struct({
    first: "char*",
    last: "char*"
})

const rust_get_headers = lib.func("get_headers", koffi.pointer(StringTuple2), [koffi.pointer(koffi.opaque("Request"))])

// req is generated in rust and pass to the javascript
console.log(koffi.decode(rust_get_headers(req), StringTuple2, 2))

My programme crash. Did I do something wrong with the decode?

[Koromix]

In the koffi.decode() call, you are trying to decode an array of tuples (two, actually), instead of just one.

This works for me:

// gcc -shared -o 138.so -O2 -Wall 138.c

typedef struct Request {
    int dummy;
} Request;

typedef struct TupleString2 {
    char *first;
    char *last;
} TupleString2;

static TupleString2 tuple = {
    .first = "hello",
    .last = "world"
};

TupleString2 *get_headers(Request *req)
{
    return &tuple;
}

const koffi = require("koffi");
const lib = koffi.load("./138.so");

const StringTuple2 = koffi.struct({
    first: "char *",
    last: "char *"
})

const rust_get_headers = lib.func("get_headers", koffi.pointer(StringTuple2), [koffi.pointer(koffi.opaque("Request"))]);

let ret = rust_get_headers(null);
let tuple = koffi.decode(ret, StringTuple2);

console.log(tuple);

[hanako-eo]

I tried to do this with one to but I have the same problem

[hanako-eo]

I'm mainly looking to get a vector from rust