/system/libraries/Zip.php

<?php

/**

 * CodeIgniter

 *

 * An open source application development framework for PHP

 *

 * This content is released under the MIT License (MIT)

 *

 * Copyright (c) 2014 - 2018, British Columbia Institute of Technology

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 *

 * @package	CodeIgniter

 * @author	EllisLab Dev Team

 * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)

 * @copyright	Copyright (c) 2014 - 2018, British Columbia Institute of Technology (http://bcit.ca/)

 * @license	http://opensource.org/licenses/MIT	MIT License

 * @link	https://codeigniter.com

 * @since	Version 1.0.0

 * @filesource

 */

defined('BASEPATH') OR exit('No direct script access allowed');



/**

 * Zip Compression Class

 *

 * This class is based on a library I found at Zend:

 * http://www.zend.com/codex.php?id=696&single=1

 *

 * The original library is a little rough around the edges so I

 * refactored it and added several additional methods -- Rick Ellis

 *

 * @package		CodeIgniter

 * @subpackage	Libraries

 * @category	Encryption

 * @author		EllisLab Dev Team

 * @link		https://codeigniter.com/user_guide/libraries/zip.html

 */

class CI_Zip {



	/**

	 * Zip data in string form

	 *

	 * @var string

	 */

	public $zipdata = '';



	/**

	 * Zip data for a directory in string form

	 *

	 * @var string

	 */

	public $directory = '';



	/**

	 * Number of files/folder in zip file

	 *

	 * @var int

	 */

	public $entries = 0;



	/**

	 * Number of files in zip

	 *

	 * @var int

	 */

	public $file_num = 0;



	/**

	 * relative offset of local header

	 *

	 * @var int

	 */

	public $offset = 0;



	/**

	 * Reference to time at init

	 *

	 * @var int

	 */

	public $now;



	/**

	 * The level of compression

	 *

	 * Ranges from 0 to 9, with 9 being the highest level.

	 *

	 * @var	int

	 */

	public $compression_level = 2;



	/**

	 * mbstring.func_overload flag

	 *

	 * @var	bool

	 */

	protected static $func_overload;



	/**

	 * Initialize zip compression class

	 *

	 * @return	void

	 */

	public function __construct()

	{

		isset(self::$func_overload) OR self::$func_overload = (extension_loaded('mbstring') && ini_get('mbstring.func_overload'));



		$this->now = time();

		log_message('info', 'Zip Compression Class Initialized');

	}



	// --------------------------------------------------------------------



	/**

	 * Add Directory

	 *

	 * Lets you add a virtual directory into which you can place files.

	 *

	 * @param	mixed	$directory	the directory name. Can be string or array

	 * @return	void

	 */

	public function add_dir($directory)

	{

		foreach ((array) $directory as $dir)

		{

			if ( ! preg_match('|.+/$|', $dir))

			{

				$dir .= '/';

			}



			$dir_time = $this->_get_mod_time($dir);

			$this->_add_dir($dir, $dir_time['file_mtime'], $dir_time['file_mdate']);

		}

	}



	// --------------------------------------------------------------------



	/**

	 * Get file/directory modification time

	 *

	 * If this is a newly created file/dir, we will set the time to 'now'

	 *

	 * @param	string	$dir	path to file

	 * @return	array	filemtime/filemdate

	 */

	protected function _get_mod_time($dir)

	{

		// filemtime() may return false, but raises an error for non-existing files

		$date = file_exists($dir) ? getdate(filemtime($dir)) : getdate($this->now);



		return array(

			'file_mtime' => ($date['hours'] << 11) + ($date['minutes'] << 5) + $date['seconds'] / 2,

			'file_mdate' => (($date['year'] - 1980) << 9) + ($date['mon'] << 5) + $date['mday']

		);

	}



	// --------------------------------------------------------------------



	/**

	 * Add Directory

	 *

	 * @param	string	$dir	the directory name

	 * @param	int	$file_mtime

	 * @param	int	$file_mdate

	 * @return	void

	 */

	protected function _add_dir($dir, $file_mtime, $file_mdate)

	{

		$dir = str_replace('\\', '/', $dir);



		$this->zipdata .=

			"\x50\x4b\x03\x04\x0a\x00\x00\x00\x00\x00"

			.pack('v', $file_mtime)

			.pack('v', $file_mdate)

			.pack('V', 0) // crc32

			.pack('V', 0) // compressed filesize

			.pack('V', 0) // uncompressed filesize

			.pack('v', self::strlen($dir)) // length of pathname

			.pack('v', 0) // extra field length

			.$dir

			// below is "data descriptor" segment

			.pack('V', 0) // crc32

			.pack('V', 0) // compressed filesize

			.pack('V', 0); // uncompressed filesize



		$this->directory .=

			"\x50\x4b\x01\x02\x00\x00\x0a\x00\x00\x00\x00\x00"

			.pack('v', $file_mtime)

			.pack('v', $file_mdate)

			.pack('V',0) // crc32

			.pack('V',0) // compressed filesize

			.pack('V',0) // uncompressed filesize

			.pack('v', self::strlen($dir)) // length of pathname

			.pack('v', 0) // extra field length

			.pack('v', 0) // file comment length

			.pack('v', 0) // disk number start

			.pack('v', 0) // internal file attributes

			.pack('V', 16) // external file attributes - 'directory' bit set

			.pack('V', $this->offset) // relative offset of local header

			.$dir;



		$this->offset = self::strlen($this->zipdata);

		$this->entries++;

	}



	// --------------------------------------------------------------------



	/**

	 * Add Data to Zip

	 *

	 * Lets you add files to the archive. If the path is included

	 * in the filename it will be placed within a directory. Make

	 * sure you use add_dir() first to create the folder.

	 *

	 * @param	mixed	$filepath	A single filepath or an array of file => data pairs

	 * @param	string	$data		Single file contents

	 * @return	void

	 */

	public function add_data($filepath, $data = NULL)

	{

		if (is_array($filepath))

		{

			foreach ($filepath as $path => $data)

			{

				$file_data = $this->_get_mod_time($path);

				$this->_add_data($path, $data, $file_data['file_mtime'], $file_data['file_mdate']);

			}

		}

		else

		{

			$file_data = $this->_get_mod_time($filepath);

			$this->_add_data($filepath, $data, $file_data['file_mtime'], $file_data['file_mdate']);

		}

	}



	// --------------------------------------------------------------------



	/**

	 * Add Data to Zip

	 *

	 * @param	string	$filepath	the file name/path

	 * @param	string	$data	the data to be encoded

	 * @param	int	$file_mtime

	 * @param	int	$file_mdate

	 * @return	void

	 */

	protected function _add_data($filepath, $data, $file_mtime, $file_mdate)

	{

		$filepath = str_replace('\\', '/', $filepath);



		$uncompressed_size = self::strlen($data);

		$crc32  = crc32($data);

		$gzdata = self::substr(gzcompress($data, $this->compression_level), 2, -4);

		$compressed_size = self::strlen($gzdata);



		$this->zipdata .=

			"\x50\x4b\x03\x04\x14\x00\x00\x00\x08\x00"

			.pack('v', $file_mtime)

			.pack('v', $file_mdate)

			.pack('V', $crc32)

			.pack('V', $compressed_size)

			.pack('V', $uncompressed_size)

			.pack('v', self::strlen($filepath)) // length of filename

			.pack('v', 0) // extra field length

			.$filepath

			.$gzdata; // "file data" segment



		$this->directory .=

			"\x50\x4b\x01\x02\x00\x00\x14\x00\x00\x00\x08\x00"

			.pack('v', $file_mtime)

			.pack('v', $file_mdate)

			.pack('V', $crc32)

			.pack('V', $compressed_size)

			.pack('V', $uncompressed_size)

			.pack('v', self::strlen($filepath)) // length of filename

			.pack('v', 0) // extra field length

			.pack('v', 0) // file comment length

			.pack('v', 0) // disk number start

			.pack('v', 0) // internal file attributes

			.pack('V', 32) // external file attributes - 'archive' bit set

			.pack('V', $this->offset) // relative offset of local header

			.$filepath;



		$this->offset = self::strlen($this->zipdata);

		$this->entries++;

		$this->file_num++;

	}



	// --------------------------------------------------------------------



	/**

	 * Read the contents of a file and add it to the zip

	 *

	 * @param	string	$path

	 * @param	bool	$archive_filepath

	 * @return	bool

	 */

	public function read_file($path, $archive_filepath = FALSE)

	{

		if (file_exists($path) && FALSE !== ($data = file_get_contents($path)))

		{

			if (is_string($archive_filepath))

			{

				$name = str_replace('\\', '/', $archive_filepath);

			}

			else

			{

				$name = str_replace('\\', '/', $path);



				if ($archive_filepath === FALSE)

				{

					$name = preg_replace('|.*/(.+)|', '\\1', $name);

				}

			}



			$this->add_data($name, $data);

			return TRUE;

		}



		return FALSE;

	}



	// ------------------------------------------------------------------------



	/**

	 * Read a directory and add it to the zip.

	 *

	 * This function recursively reads a folder and everything it contains (including

	 * sub-folders) and creates a zip based on it. Whatever directory structure

	 * is in the original file path will be recreated in the zip file.

	 *

	 * @param	string	$path	path to source directory

	 * @param	bool	$preserve_filepath

	 * @param	string	$root_path

	 * @return	bool

	 */

	public function read_dir($path, $preserve_filepath = TRUE, $root_path = NULL)

	{

		$path = rtrim($path, '/\\').DIRECTORY_SEPARATOR;

		if ( ! $fp = @opendir($path))

		{

			return FALSE;

		}



		// Set the original directory root for child dir's to use as relative

		if ($root_path === NULL)

		{

			$root_path = str_replace(array('\\', '/'), DIRECTORY_SEPARATOR, dirname($path)).DIRECTORY_SEPARATOR;

		}



		while (FALSE !== ($file = readdir($fp)))

		{

			if ($file[0] === '.')

			{

				continue;

			}



			if (is_dir($path.$file))

			{

				$this->read_dir($path.$file.DIRECTORY_SEPARATOR, $preserve_filepath, $root_path);

			}

			elseif (FALSE !== ($data = file_get_contents($path.$file)))

			{

				$name = str_replace(array('\\', '/'), DIRECTORY_SEPARATOR, $path);

				if ($preserve_filepath === FALSE)

				{

					$name = str_replace($root_path, '', $name);

				}



				$this->add_data($name.$file, $data);

			}

		}



		closedir($fp);

		return TRUE;

	}



	// --------------------------------------------------------------------



	/**

	 * Get the Zip file

	 *

	 * @return	string	(binary encoded)

	 */

	public function get_zip()

	{

		// Is there any data to return?

		if ($this->entries === 0)

		{

			return FALSE;

		}



		return $this->zipdata

			.$this->directory."\x50\x4b\x05\x06\x00\x00\x00\x00"

			.pack('v', $this->entries) // total # of entries "on this disk"

			.pack('v', $this->entries) // total # of entries overall

			.pack('V', self::strlen($this->directory)) // size of central dir

			.pack('V', self::strlen($this->zipdata)) // offset to start of central dir

			."\x00\x00"; // .zip file comment length

	}



	// --------------------------------------------------------------------



	/**

	 * Write File to the specified directory

	 *

	 * Lets you write a file

	 *

	 * @param	string	$filepath	the file name

	 * @return	bool

	 */

	public function archive($filepath)

	{

		if ( ! ($fp = @fopen($filepath, 'w+b')))

		{

			return FALSE;

		}



		flock($fp, LOCK_EX);



		for ($result = $written = 0, $data = $this->get_zip(), $length = self::strlen($data); $written < $length; $written += $result)

		{

			if (($result = fwrite($fp, self::substr($data, $written))) === FALSE)

			{

				break;

			}

		}



		flock($fp, LOCK_UN);

		fclose($fp);



		return is_int($result);

	}



	// --------------------------------------------------------------------



	/**

	 * Download

	 *

	 * @param	string	$filename	the file name

	 * @return	void

	 */

	public function download($filename = 'backup.zip')

	{

		if ( ! preg_match('|.+?\.zip$|', $filename))

		{

			$filename .= '.zip';

		}



		get_instance()->load->helper('download');

		$get_zip = $this->get_zip();

		$zip_content =& $get_zip;



		force_download($filename, $zip_content);

	}



	// --------------------------------------------------------------------



	/**

	 * Initialize Data

	 *

	 * Lets you clear current zip data. Useful if you need to create

	 * multiple zips with different data.

	 *

	 * @return	CI_Zip

	 */

	public function clear_data()

	{

		$this->zipdata = '';

		$this->directory = '';

		$this->entries = 0;

		$this->file_num = 0;

		$this->offset = 0;

		return $this;

	}



	// --------------------------------------------------------------------



	/**

	 * Byte-safe strlen()

	 *

	 * @param	string	$str

	 * @return	int

	 */

	protected static function strlen($str)

	{

		return (self::$func_overload)

			? mb_strlen($str, '8bit')

			: strlen($str);

	}



	// --------------------------------------------------------------------



	/**

	 * Byte-safe substr()

	 *

	 * @param	string	$str

	 * @param	int	$start

	 * @param	int	$length

	 * @return	string

	 */

	protected static function substr($str, $start, $length = NULL)

	{

		if (self::$func_overload)

		{

			// mb_substr($str, $start, null, '8bit') returns an empty

			// string on PHP 5.3

			isset($length) OR $length = ($start >= 0 ? self::strlen($str) - $start : -$start);

			return mb_substr($str, $start, $length, '8bit');

		}



		return isset($length)

			? substr($str, $start, $length)

			: substr($str, $start);

	}

}