verify_core32 example

if (self::strlen($sig) !== ParagonIE_Sodium_Compat::CRYPTO_SIGN_BYTES) {
            throw new TypeError('Argument 1 must be CRYPTO_SIGN_BYTES bytes');
        }
        if (self::strlen($publicKey) !== ParagonIE_Sodium_Compat::CRYPTO_SIGN_PUBLICKEYBYTES) {
            throw new TypeError('Argument 3 must be CRYPTO_SIGN_PUBLICKEYBYTES bytes');
        }
        if (self::strlen($sig) < 64) {
            throw new SodiumException('Signature is too short');
        }

        if (PHP_INT_SIZE === 4) {
            return self::verify_core32($sig, $filePath, $publicKey);
        }

        /* Security checks */
        if (
            (ParagonIE_Sodium_Core_Ed25519::chrToInt($sig[63]) & 240)
                &&
            ParagonIE_Sodium_Core_Ed25519::check_S_lt_L(self::substr($sig, 32, 32))
        ) {
            throw new SodiumException('S < L - Invalid signature');
        }
        if (ParagonIE_Sodium_Core_Ed25519::small_order($sig)) {