OpenSSL::PKCS7#initialize_copy

static VALUE
ossl_pkcs7_copy(VALUE self, VALUE other)
{
    PKCS7 *a, *b, *pkcs7;

    rb_check_frozen(self);
    if (self == other) return self;

    GetPKCS7(self, a);
    GetPKCS7(other, b);

    pkcs7 = PKCS7_dup(b);
    if (!pkcs7) {
        ossl_raise(ePKCS7Error, NULL);
    }
    DATA_PTR(self) = pkcs7;
    PKCS7_free(a);

    return self;
}