ci-bonfire / Sprint

system/helpers/download_helper.php

<?php

For compatibility and reusability of your code, PSR1 recommends that a file should introduce either new symbols (like classes, functions, etc.) or have side-effects (like outputting something, or including other files), but not both at the same time. The first symbol is defined on line 64 and the first side effect is on line 38.

/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2015, 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. (http://ellislab.com/)
 * @copyright	Copyright (c) 2014 - 2015, British Columbia Institute of Technology (http://bcit.ca/)
 * @license	http://opensource.org/licenses/MIT	MIT License
 * @link	http://codeigniter.com
 * @since	Version 1.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * CodeIgniter Download Helpers
 *
 * @package		CodeIgniter
 * @subpackage	Helpers
 * @category	Helpers
 * @author		EllisLab Dev Team
 * @link		http://codeigniter.com/user_guide/helpers/download_helper.html
 */

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

if ( ! function_exists('force_download'))
{
	/**
	 * Force Download
	 *
	 * Generates headers that force a download to happen
	 *
	 * @param	string	filename
	 * @param	mixed	the data to be downloaded
	 * @param	bool	whether to try and send the actual file MIME type
	 * @return	void
	 */
	function force_download($filename = '', $data = '', $set_mime = FALSE)
	{
		if ($filename === '' OR $data === '')
		{
			return;
		}
		elseif ($data === NULL)
		{
			if ( ! @is_file($filename) OR ($filesize = @filesize($filename)) === FALSE)
			{
				return;
			}

			$filepath = $filename;
			$filename = explode('/', str_replace(DIRECTORY_SEPARATOR, '/', $filename));
			$filename = end($filename);
		}
		else
		{
			$filesize = strlen($data);
		}

		// Set the default MIME type to send
		$mime = 'application/octet-stream';

		$x = explode('.', $filename);
		$extension = end($x);

		if ($set_mime === TRUE)
		{
			if (count($x) === 1 OR $extension === '')
			{
				/* If we're going to detect the MIME type,
				 * we'll need a file extension.
				 */
				return;
			}

			// Load the mime types
			$mimes =& get_mimes();

			// Only change the default MIME if we can find one
			if (isset($mimes[$extension]))
			{
				$mime = is_array($mimes[$extension]) ? $mimes[$extension][0] : $mimes[$extension];
			}
		}

		/* It was reported that browsers on Android 2.1 (and possibly older as well)
		 * need to have the filename extension upper-cased in order to be able to
		 * download it.
		 *
		 * Reference: http://digiblog.de/2011/04/19/android-and-the-download-file-headers/
		 */
		if (count($x) !== 1 && isset($_SERVER['HTTP_USER_AGENT']) && preg_match('/Android\s(1|2\.[01])/', $_SERVER['HTTP_USER_AGENT']))
		{
			$x[count($x) - 1] = strtoupper($extension);
			$filename = implode('.', $x);
		}

		if ($data === NULL && ($fp = @fopen($filepath, 'rb')) === FALSE)
		{
			return;
		}

		// Clean output buffer
		if (ob_get_level() !== 0 && @ob_end_clean() === FALSE)
		{
			@ob_clean();
		}

		// Generate the server headers
		header('Content-Type: '.$mime);
		header('Content-Disposition: attachment; filename="'.$filename.'"');
		header('Expires: 0');
		header('Content-Transfer-Encoding: binary');
		header('Content-Length: '.$filesize);
		header('Cache-Control: private, no-transform, no-store, must-revalidate');

		// If we have raw data - just dump it
		if ($data !== NULL)
		{
			exit($data);
		}

		// Flush 1MB chunks of data
		while ( ! feof($fp) && ($data = fread($fp, 1048576)) !== FALSE)
		{
			echo $data;
		}

		fclose($fp);
		exit;
	}
}