OpenSSL::PKey::EC#initialize_copy

HAVE_EVP_PKEY_DUP
static VALUE
ossl_ec_key_initialize_copy(VALUE self, VALUE other)
{
    EVP_PKEY *pkey;
    EC_KEY *ec, *ec_new;

    TypedData_Get_Struct(self, EVP_PKEY, &ossl_evp_pkey_type, pkey);
    if (pkey)
        rb_raise(rb_eTypeError, "pkey already initialized");
    GetEC(other, ec);

    ec_new = EC_KEY_dup(ec);
    if (!ec_new)
        ossl_raise(eECError, "EC_KEY_dup");

    pkey = EVP_PKEY_new();
    if (!pkey || EVP_PKEY_assign_EC_KEY(pkey, ec_new) != 1) {
        EC_KEY_free(ec_new);
        ossl_raise(eECError, "EVP_PKEY_assign_EC_KEY");
    }
    RTYPEDDATA_DATA(self) = pkey;

    return self;
}