Zip.php

Go to the documentation of this file.

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package             CodeIgniter
 * @author              ExpressionEngine Dev Team
 * @copyright   Copyright (c) 2008, EllisLab, Inc.
 * @license             http://codeigniter.com/user_guide/license.html
 * @link                http://codeigniter.com
 * @since               Version 1.0
 * @filesource
 */

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

/**
 * 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              ExpressionEngine Dev Team
 * @link                http://codeigniter.com/user_guide/libraries/zip.html
 */
class CI_Zip  {

        var $zipdata    = '';
        var $directory  = '';
        var $entries    = 0;
        var $file_num   = 0;
        var $offset             = 0;

        function CI_Zip()
        {
                log_message('debug', "Zip Compression Class Initialized");
        }

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

        /**
         * Add Directory
         *
         * Lets you add a virtual directory into which you can place files.
         *
         * @access      public
         * @param       mixed   the directory name. Can be string or array
         * @return      void
         */
        function add_dir($directory)
        {
                foreach ((array)$directory as $dir)
                {
                        if ( ! preg_match("|.+/$|", $dir))
                        {
                                $dir .= '/';
                        }

                        $this->_add_dir($dir);
                }
        }

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

        /**
         * Add Directory
         *
         * @access      private
         * @param       string  the directory name
         * @return      void
         */
        function _add_dir($dir)
        {
                $dir = str_replace("\\", "/", $dir);

                $this->zipdata .=
                        "\x50\x4b\x03\x04\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"
                        .pack('V', 0) // crc32
                        .pack('V', 0) // compressed filesize
                        .pack('V', 0) // uncompressed filesize
                        .pack('v', strlen($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

                $this->directory .=
                        "\x50\x4b\x01\x02\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00"
                        .pack('V',0) // crc32
                        .pack('V',0) // compressed filesize
                        .pack('V',0) // uncompressed filesize
                        .pack('v', strlen($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;

                $this->offset = strlen($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.
         *
         * @access      public
         * @param       mixed
         * @param       string
         * @return      void
         */     
        function add_data($filepath, $data = NULL)
        {
                if (is_array($filepath))
                {
                        foreach ($filepath as $path => $data)
                        {
                                $this->_add_data($path, $data);
                        }
                }
                else
                {
                        $this->_add_data($filepath, $data);
                }
        }

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

        /**
         * Add Data to Zip
         *
         * @access      private
         * @param       string  the file name/path
         * @param       string  the data to be encoded
         * @return      void
         */     
        function _add_data($filepath, $data)
        {
                $filepath = str_replace("\\", "/", $filepath);

                $uncompressed_size = strlen($data);
                $crc32  = crc32($data);

                $gzdata = gzcompress($data);
                $gzdata = substr($gzdata, 2, -4);
                $compressed_size = strlen($gzdata);

                $this->zipdata .=
                        "\x50\x4b\x03\x04\x14\x00\x00\x00\x08\x00\x00\x00\x00\x00"
                        .pack('V', $crc32)
                        .pack('V', $compressed_size)
                        .pack('V', $uncompressed_size)
                        .pack('v', strlen($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\x00\x00\x00\x00"
                        .pack('V', $crc32)
                        .pack('V', $compressed_size)
                        .pack('V', $uncompressed_size)
                        .pack('v', strlen($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;

                $this->offset = strlen($this->zipdata);
                $this->entries++;
                $this->file_num++;
        }
        
        // --------------------------------------------------------------------

        /**
         * Read the contents of a file and add it to the zip
         *
         * @access      public
         * @return      bool
         */     
        function read_file($path, $preserve_filepath = FALSE)
        {
                if ( ! file_exists($path))
                {
                        return FALSE;
                }

                if (FALSE !== ($data = file_get_contents($path)))
                {
                        $name = str_replace("\\", "/", $path);
                        
                        if ($preserve_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.
         *
         * @access      public
         * @param       string  path to source
         * @return      bool
         */     
        function read_dir($path)
        {       
                if ($fp = @opendir($path))
                {
                        while (FALSE !== ($file = readdir($fp)))
                        {
                                if (@is_dir($path.$file) && substr($file, 0, 1) != '.')
                                {                                       
                                        $this->read_dir($path.$file."/");
                                }
                                elseif (substr($file, 0, 1) != ".")
                                {
                                        if (FALSE !== ($data = file_get_contents($path.$file)))
                                        {                                               
                                                $this->add_data(str_replace("\\", "/", $path).$file, $data);
                                        }
                                }
                        }
                        return TRUE;
                }
        }

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

        /**
         * Get the Zip file
         *
         * @access      public
         * @return      binary string
         */     
        function get_zip()
        {
                // Is there any data to return?
                if ($this->entries == 0)
                {
                        return FALSE;
                }

                $zip_data = $this->zipdata;
                $zip_data .= $this->directory."\x50\x4b\x05\x06\x00\x00\x00\x00";
                $zip_data .= pack('v', $this->entries); // total # of entries "on this disk"
                $zip_data .= pack('v', $this->entries); // total # of entries overall
                $zip_data .= pack('V', strlen($this->directory)); // size of central dir
                $zip_data .= pack('V', strlen($this->zipdata)); // offset to start of central dir
                $zip_data .= "\x00\x00"; // .zip file comment length

                return $zip_data;
        }
        
        // --------------------------------------------------------------------

        /**
         * Write File to the specified directory
         *
         * Lets you write a file
         *
         * @access      public
         * @param       string  the file name
         * @return      bool
         */     
        function archive($filepath)
        {
                if ( ! ($fp = @fopen($filepath, FOPEN_WRITE_CREATE_DESTRUCTIVE)))
                {
                        return FALSE;
                }

                flock($fp, LOCK_EX);    
                fwrite($fp, $this->get_zip());
                flock($fp, LOCK_UN);
                fclose($fp);

                return TRUE;    
        }

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

        /**
         * Download
         *
         * @access      public
         * @param       string  the file name
         * @param       string  the data to be encoded
         * @return      bool
         */
        function download($filename = 'backup.zip')
        {
                if ( ! preg_match("|.+?\.zip$|", $filename))
                {
                        $filename .= '.zip';
                }

                $zip_content =& $this->get_zip();

                $CI =& get_instance();
                $CI->load->helper('download');

                force_download($filename, $zip_content);
        }

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

        /**
         * Initialize Data
         *
         * Lets you clear current zip data.  Useful if you need to create
         * multiple zips with different data.
         *
         * @access      public
         * @return      void
         */             
        function clear_data()
        {
                $this->zipdata          = '';
                $this->directory        = '';
                $this->entries          = 0;
                $this->file_num         = 0;
                $this->offset           = 0;
        }
        
}

/* End of file Zip.php */
/* Location: ./system/libraries/Zip.php */