1 files changed, 50 insertions, 0 deletions
diff --git a/phpBB/phpbb/filesystem.php b/phpBB/phpbb/filesystem.php
new file mode 100644
index 0000000000..77517082e5
--- /dev/null
+++ b/phpBB/phpbb/filesystem.php
@@ -0,0 +1,50 @@
+<?php
+/**
+*
+* This file is part of the phpBB Forum Software package.
+*
+* @copyright (c) phpBB Limited <https://www.phpbb.com>
+* @license GNU General Public License, version 2 (GPL-2.0)
+*
+* For full copyright and license information, please see
+* the docs/CREDITS.txt file.
+*
+*/
+
+namespace phpbb;
+
+/**
+* A class with various functions that are related to paths, files and the filesystem
+*/
+class filesystem
+{
+	/**
+	* Eliminates useless . and .. components from specified path.
+	*
+	* @param string $path Path to clean
+	* @return string Cleaned path
+	*/
+	public function clean_path($path)
+	{
+		$exploded = explode('/', $path);
+		$filtered = array();
+		foreach ($exploded as $part)
+		{
+			if ($part === '.' && !empty($filtered))
+			{
+				continue;
+			}
+
+			if ($part === '..' && !empty($filtered) && $filtered[sizeof($filtered) - 1] !== '.' && $filtered[sizeof($filtered) - 1] !== '..')
+			{
+				array_pop($filtered);
+			}
+			else
+			{
+				$filtered[] = $part;
+			}
+		}
+		$path = implode('/', $filtered);
+		return $path;
+	}
+}