add_file

static VALUE
ossl_x509store_add_file(VALUE self, VALUE file)
{
    X509_STORE *store;
    X509_LOOKUP *lookup;
    char *path = NULL;

    if(file != Qnil){
        rb_check_safe_obj(file);
        path = StringValueCStr(file);
    }
    GetX509Store(self, store);
    lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
    if(lookup == NULL) ossl_raise(eX509StoreError, NULL);
    if(X509_LOOKUP_load_file(lookup, path, X509_FILETYPE_PEM) != 1){
        ossl_raise(eX509StoreError, NULL);
    }
#if OPENSSL_VERSION_NUMBER < 0x10101000 || defined(LIBRESSL_VERSION_NUMBER)
    /*
     * X509_load_cert_crl_file() which is called from X509_LOOKUP_load_file()
     * did not check the return value of X509_STORE_add_{cert,crl}(), leaking
     * "cert already in hash table" errors on the error queue, if duplicate
     * certificates are found. This will be fixed by OpenSSL 1.1.1.
     */
    ossl_clear_error();
#endif

    return self;
}