--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Polyfill\Php54;
+
+/**
+ * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @internal
+ */
+final class Php54
+{
+ public static function hex2bin($data)
+ {
+ $len = strlen($data);
+
+ if (null === $len) {
+ return;
+ }
+ if ($len % 2) {
+ trigger_error('hex2bin(): Hexadecimal input string must have an even length', E_USER_WARNING);
+
+ return false;
+ }
+
+ return pack('H*', $data);
+ }
+}