OpenSSL::X509::Attribute#value

static VALUE
ossl_x509attr_get_value(VALUE self)
{
    X509_ATTRIBUTE *attr;
    STACK_OF(ASN1_TYPE) *sk;
    VALUE str;
    int i, count, len;
    unsigned char *p;

    GetX509Attr(self, attr);
    /* there is no X509_ATTRIBUTE_get0_set() :( */
    if (!(sk = sk_ASN1_TYPE_new_null()))
        ossl_raise(eX509AttrError, "sk_new");

    count = X509_ATTRIBUTE_count(attr);
    for (i = 0; i < count; i++)
        sk_ASN1_TYPE_push(sk, X509_ATTRIBUTE_get0_type(attr, i));

    if ((len = i2d_ASN1_SET_ANY(sk, NULL)) <= 0) {
        sk_ASN1_TYPE_free(sk);
        ossl_raise(eX509AttrError, NULL);
    }
    str = rb_str_new(0, len);
    p = (unsigned char *)RSTRING_PTR(str);
    if (i2d_ASN1_SET_ANY(sk, &p) <= 0) {
        sk_ASN1_TYPE_free(sk);
        ossl_raise(eX509AttrError, NULL);
    }
    ossl_str_adjust(str, p);
    sk_ASN1_TYPE_free(sk);

    return rb_funcall(mASN1, rb_intern("decode"), 1, str);
}