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<?php/*** CodeIgniter** An open source application development framework for PHP** This content is released under the MIT License (MIT)** Copyright (c) 2014 - 2016, 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 - 2016, 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');/*** File Uploading Class** @package CodeIgniter* @subpackage Libraries* @category Uploads* @author EllisLab Dev Team* @link https://codeigniter.com/user_guide/libraries/file_uploading.html*/class CI_Upload {/*** Maximum file size** @var int*/public $max_size = 0;/*** Maximum image width** @var int*/public $max_width = 0;/*** Maximum image height** @var int*/public $max_height = 0;/*** Minimum image width** @var int*/public $min_width = 0;/*** Minimum image height** @var int*/public $min_height = 0;/*** Maximum filename length** @var int*/public $max_filename = 0;/*** Maximum duplicate filename increment ID** @var int*/public $max_filename_increment = 100;/*** Allowed file types** @var string*/public $allowed_types = '';/*** Temporary filename** @var string*/public $file_temp = '';/*** Filename** @var string*/public $file_name = '';/*** Original filename** @var string*/public $orig_name = '';/*** File type** @var string*/public $file_type = '';/*** File size** @var int*/public $file_size = NULL;/*** Filename extension** @var string*/public $file_ext = '';/*** Force filename extension to lowercase** @var string*/public $file_ext_tolower = FALSE;/*** Upload path** @var string*/public $upload_path = '';/*** Overwrite flag** @var bool*/public $overwrite = FALSE;/*** Obfuscate filename flag** @var bool*/public $encrypt_name = FALSE;/*** Is image flag** @var bool*/public $is_image = FALSE;/*** Image width** @var int*/public $image_width = NULL;/*** Image height** @var int*/public $image_height = NULL;/*** Image type** @var string*/public $image_type = '';/*** Image size string** @var string*/public $image_size_str = '';/*** Error messages list** @var array*/public $error_msg = array();/*** Remove spaces flag** @var bool*/public $remove_spaces = TRUE;/*** MIME detection flag** @var bool*/public $detect_mime = TRUE;/*** XSS filter flag** @var bool*/public $xss_clean = FALSE;/*** Apache mod_mime fix flag** @var bool*/public $mod_mime_fix = TRUE;/*** Temporary filename prefix** @var string*/public $temp_prefix = 'temp_file_';/*** Filename sent by the client** @var bool*/public $client_name = '';// --------------------------------------------------------------------/*** Filename override** @var string*/protected $_file_name_override = '';/*** MIME types list** @var array*/protected $_mimes = array();/*** CI Singleton** @var object*/protected $_CI;// --------------------------------------------------------------------/*** Constructor** @param array $config* @return void*/public function __construct($config = array()){empty($config) OR $this->initialize($config, FALSE);$this->_mimes =& get_mimes();$this->_CI =& get_instance();log_message('info', 'Upload Class Initialized');}// --------------------------------------------------------------------/*** Initialize preferences** @param array $config* @param bool $reset* @return CI_Upload*/public function initialize(array $config = array(), $reset = TRUE){$reflection = new ReflectionClass($this);if ($reset === TRUE){$defaults = $reflection->getDefaultProperties();foreach (array_keys($defaults) as $key){if ($key[0] === '_'){continue;}if (isset($config[$key])){if ($reflection->hasMethod('set_'.$key)){$this->{'set_'.$key}($config[$key]);}else{$this->$key = $config[$key];}}else{$this->$key = $defaults[$key];}}}else{foreach ($config as $key => &$value){if ($key[0] !== '_' && $reflection->hasProperty($key)){if ($reflection->hasMethod('set_'.$key)){$this->{'set_'.$key}($value);}else{$this->$key = $value;}}}}// if a file_name was provided in the config, use it instead of the user input// supplied file name for all uploads until initialized again$this->_file_name_override = $this->file_name;return $this;}// --------------------------------------------------------------------/*** Perform the file upload** @param string $field* @return bool*/public function do_upload($field = 'userfile'){// Is $_FILES[$field] set? If not, no reason to continue.if (isset($_FILES[$field])){$_file = $_FILES[$field];}// Does the field name contain array notation?elseif (($c = preg_match_all('/(?:^[^\[]+)|\[[^]]*\]/', $field, $matches)) > 1){$_file = $_FILES;for ($i = 0; $i < $c; $i++){// We can't track numeric iterations, only full field names are acceptedif (($field = trim($matches[0][$i], '[]')) === '' OR ! isset($_file[$field])){$_file = NULL;break;}$_file = $_file[$field];}}if ( ! isset($_file)){$this->set_error('upload_no_file_selected', 'debug');return FALSE;}// Is the upload path valid?if ( ! $this->validate_upload_path()){// errors will already be set by validate_upload_path() so just return FALSEreturn FALSE;}// Was the file able to be uploaded? If not, determine the reason why.if ( ! is_uploaded_file($_file['tmp_name'])){$error = isset($_file['error']) ? $_file['error'] : 4;switch ($error){case UPLOAD_ERR_INI_SIZE:$this->set_error('upload_file_exceeds_limit', 'info');break;case UPLOAD_ERR_FORM_SIZE:$this->set_error('upload_file_exceeds_form_limit', 'info');break;case UPLOAD_ERR_PARTIAL:$this->set_error('upload_file_partial', 'debug');break;case UPLOAD_ERR_NO_FILE:$this->set_error('upload_no_file_selected', 'debug');break;case UPLOAD_ERR_NO_TMP_DIR:$this->set_error('upload_no_temp_directory', 'error');break;case UPLOAD_ERR_CANT_WRITE:$this->set_error('upload_unable_to_write_file', 'error');break;case UPLOAD_ERR_EXTENSION:$this->set_error('upload_stopped_by_extension', 'debug');break;default:$this->set_error('upload_no_file_selected', 'debug');break;}return FALSE;}// Set the uploaded data as class variables$this->file_temp = $_file['tmp_name'];$this->file_size = $_file['size'];// Skip MIME type detection?if ($this->detect_mime !== FALSE){$this->_file_mime_type($_file);}$this->file_type = preg_replace('/^(.+?);.*$/', '\\1', $this->file_type);$this->file_type = strtolower(trim(stripslashes($this->file_type), '"'));$this->file_name = $this->_prep_filename($_file['name']);$this->file_ext = $this->get_extension($this->file_name);$this->client_name = $this->file_name;// Is the file type allowed to be uploaded?if ( ! $this->is_allowed_filetype()){$this->set_error('upload_invalid_filetype', 'debug');return FALSE;}// if we're overriding, let's now make sure the new name and type is allowedif ($this->_file_name_override !== ''){$this->file_name = $this->_prep_filename($this->_file_name_override);// If no extension was provided in the file_name config item, use the uploaded oneif (strpos($this->_file_name_override, '.') === FALSE){$this->file_name .= $this->file_ext;}else{// An extension was provided, let's have it!$this->file_ext = $this->get_extension($this->_file_name_override);}if ( ! $this->is_allowed_filetype(TRUE)){$this->set_error('upload_invalid_filetype', 'debug');return FALSE;}}// Convert the file size to kilobytesif ($this->file_size > 0){$this->file_size = round($this->file_size/1024, 2);}// Is the file size within the allowed maximum?if ( ! $this->is_allowed_filesize()){$this->set_error('upload_invalid_filesize', 'info');return FALSE;}// Are the image dimensions within the allowed size?// Note: This can fail if the server has an open_basedir restriction.if ( ! $this->is_allowed_dimensions()){$this->set_error('upload_invalid_dimensions', 'info');return FALSE;}// Sanitize the file name for security$this->file_name = $this->_CI->security->sanitize_filename($this->file_name);// Truncate the file name if it's too longif ($this->max_filename > 0){$this->file_name = $this->limit_filename_length($this->file_name, $this->max_filename);}// Remove white spaces in the nameif ($this->remove_spaces === TRUE){$this->file_name = preg_replace('/\s+/', '_', $this->file_name);}if ($this->file_ext_tolower && ($ext_length = strlen($this->file_ext))){// file_ext was previously lower-cased by a get_extension() call$this->file_name = substr($this->file_name, 0, -$ext_length).$this->file_ext;}/** Validate the file name* This function appends an number onto the end of* the file if one with the same name already exists.* If it returns false there was a problem.*/$this->orig_name = $this->file_name;if (FALSE === ($this->file_name = $this->set_filename($this->upload_path, $this->file_name))){return FALSE;}/** Run the file through the XSS hacking filter* This helps prevent malicious code from being* embedded within a file. Scripts can easily* be disguised as images or other file types.*/if ($this->xss_clean && $this->do_xss_clean() === FALSE){$this->set_error('upload_unable_to_write_file', 'error');return FALSE;}/** Move the file to the final destination* To deal with different server configurations* we'll attempt to use copy() first. If that fails* we'll use move_uploaded_file(). One of the two should* reliably work in most environments*/if ( ! @copy($this->file_temp, $this->upload_path.$this->file_name)){if ( ! @move_uploaded_file($this->file_temp, $this->upload_path.$this->file_name)){$this->set_error('upload_destination_error', 'error');return FALSE;}}/** Set the finalized image dimensions* This sets the image width/height (assuming the* file was an image). We use this information* in the "data" function.*/$this->set_image_properties($this->upload_path.$this->file_name);return TRUE;}// --------------------------------------------------------------------/*** Finalized Data Array** Returns an associative array containing all of the information* related to the upload, allowing the developer easy access in one array.** @param string $index* @return mixed*/public function data($index = NULL){$data = array('file_name' => $this->file_name,'file_type' => $this->file_type,'file_path' => $this->upload_path,'full_path' => $this->upload_path.$this->file_name,'raw_name' => substr($this->file_name, 0, -strlen($this->file_ext)),'orig_name' => $this->orig_name,'client_name' => $this->client_name,'file_ext' => $this->file_ext,'file_size' => $this->file_size,'is_image' => $this->is_image(),'image_width' => $this->image_width,'image_height' => $this->image_height,'image_type' => $this->image_type,'image_size_str' => $this->image_size_str,);if ( ! empty($index)){return isset($data[$index]) ? $data[$index] : NULL;}return $data;}// --------------------------------------------------------------------/*** Set Upload Path** @param string $path* @return CI_Upload*/public function set_upload_path($path){// Make sure it has a trailing slash$this->upload_path = rtrim($path, '/').'/';return $this;}// --------------------------------------------------------------------/*** Set the file name** This function takes a filename/path as input and looks for the* existence of a file with the same name. If found, it will append a* number to the end of the filename to avoid overwriting a pre-existing file.** @param string $path* @param string $filename* @return string*/public function set_filename($path, $filename){if ($this->encrypt_name === TRUE){$filename = md5(uniqid(mt_rand())).$this->file_ext;}if ($this->overwrite === TRUE OR ! file_exists($path.$filename)){return $filename;}$filename = str_replace($this->file_ext, '', $filename);$new_filename = '';for ($i = 1; $i < $this->max_filename_increment; $i++){if ( ! file_exists($path.$filename.$i.$this->file_ext)){$new_filename = $filename.$i.$this->file_ext;break;}}if ($new_filename === ''){$this->set_error('upload_bad_filename', 'debug');return FALSE;}else{return $new_filename;}}// --------------------------------------------------------------------/*** Set Maximum File Size** @param int $n* @return CI_Upload*/public function set_max_filesize($n){$this->max_size = ($n < 0) ? 0 : (int) $n;return $this;}// --------------------------------------------------------------------/*** Set Maximum File Size** An internal alias to set_max_filesize() to help with configuration* as initialize() will look for a set_<property_name>() method ...** @param int $n* @return CI_Upload*/protected function set_max_size($n){return $this->set_max_filesize($n);}// --------------------------------------------------------------------/*** Set Maximum File Name Length** @param int $n* @return CI_Upload*/public function set_max_filename($n){$this->max_filename = ($n < 0) ? 0 : (int) $n;return $this;}// --------------------------------------------------------------------/*** Set Maximum Image Width** @param int $n* @return CI_Upload*/public function set_max_width($n){$this->max_width = ($n < 0) ? 0 : (int) $n;return $this;}// --------------------------------------------------------------------/*** Set Maximum Image Height** @param int $n* @return CI_Upload*/public function set_max_height($n){$this->max_height = ($n < 0) ? 0 : (int) $n;return $this;}// --------------------------------------------------------------------/*** Set minimum image width** @param int $n* @return CI_Upload*/public function set_min_width($n){$this->min_width = ($n < 0) ? 0 : (int) $n;return $this;}// --------------------------------------------------------------------/*** Set minimum image height** @param int $n* @return CI_Upload*/public function set_min_height($n){$this->min_height = ($n < 0) ? 0 : (int) $n;return $this;}// --------------------------------------------------------------------/*** Set Allowed File Types** @param mixed $types* @return CI_Upload*/public function set_allowed_types($types){$this->allowed_types = (is_array($types) OR $types === '*')? $types: explode('|', $types);return $this;}// --------------------------------------------------------------------/*** Set Image Properties** Uses GD to determine the width/height/type of image** @param string $path* @return CI_Upload*/public function set_image_properties($path = ''){if ($this->is_image() && function_exists('getimagesize')){if (FALSE !== ($D = @getimagesize($path))){$types = array(1 => 'gif', 2 => 'jpeg', 3 => 'png');$this->image_width = $D[0];$this->image_height = $D[1];$this->image_type = isset($types[$D[2]]) ? $types[$D[2]] : 'unknown';$this->image_size_str = $D[3]; // string containing height and width}}return $this;}// --------------------------------------------------------------------/*** Set XSS Clean** Enables the XSS flag so that the file that was uploaded* will be run through the XSS filter.** @param bool $flag* @return CI_Upload*/public function set_xss_clean($flag = FALSE){$this->xss_clean = ($flag === TRUE);return $this;}// --------------------------------------------------------------------/*** Validate the image** @return bool*/public function is_image(){// IE will sometimes return odd mime-types during upload, so here we just standardize all// jpegs or pngs to the same file type.$png_mimes = array('image/x-png');$jpeg_mimes = array('image/jpg', 'image/jpe', 'image/jpeg', 'image/pjpeg');if (in_array($this->file_type, $png_mimes)){$this->file_type = 'image/png';}elseif (in_array($this->file_type, $jpeg_mimes)){$this->file_type = 'image/jpeg';}$img_mimes = array('image/gif', 'image/jpeg', 'image/png');return in_array($this->file_type, $img_mimes, TRUE);}// --------------------------------------------------------------------/*** Verify that the filetype is allowed** @param bool $ignore_mime* @return bool*/public function is_allowed_filetype($ignore_mime = FALSE){if ($this->allowed_types === '*'){return TRUE;}if (empty($this->allowed_types) OR ! is_array($this->allowed_types)){$this->set_error('upload_no_file_types', 'debug');return FALSE;}$ext = strtolower(ltrim($this->file_ext, '.'));if ( ! in_array($ext, $this->allowed_types, TRUE)){return FALSE;}// Images get some additional checksif (in_array($ext, array('gif', 'jpg', 'jpeg', 'jpe', 'png'), TRUE) && @getimagesize($this->file_temp) === FALSE){return FALSE;}if ($ignore_mime === TRUE){return TRUE;}if (isset($this->_mimes[$ext])){return is_array($this->_mimes[$ext])? in_array($this->file_type, $this->_mimes[$ext], TRUE): ($this->_mimes[$ext] === $this->file_type);}return FALSE;}// --------------------------------------------------------------------/*** Verify that the file is within the allowed size** @return bool*/public function is_allowed_filesize(){return ($this->max_size === 0 OR $this->max_size > $this->file_size);}// --------------------------------------------------------------------/*** Verify that the image is within the allowed width/height** @return bool*/public function is_allowed_dimensions(){if ( ! $this->is_image()){return TRUE;}if (function_exists('getimagesize')){$D = @getimagesize($this->file_temp);if ($this->max_width > 0 && $D[0] > $this->max_width){return FALSE;}if ($this->max_height > 0 && $D[1] > $this->max_height){return FALSE;}if ($this->min_width > 0 && $D[0] < $this->min_width){return FALSE;}if ($this->min_height > 0 && $D[1] < $this->min_height){return FALSE;}}return TRUE;}// --------------------------------------------------------------------/*** Validate Upload Path** Verifies that it is a valid upload path with proper permissions.** @return bool*/public function validate_upload_path(){if ($this->upload_path === ''){$this->set_error('upload_no_filepath', 'error');return FALSE;}if (realpath($this->upload_path) !== FALSE){$this->upload_path = str_replace('\\', '/', realpath($this->upload_path));}if ( ! is_dir($this->upload_path)){$this->set_error('upload_no_filepath', 'error');return FALSE;}if ( ! is_really_writable($this->upload_path)){$this->set_error('upload_not_writable', 'error');return FALSE;}$this->upload_path = preg_replace('/(.+?)\/*$/', '\\1/', $this->upload_path);return TRUE;}// --------------------------------------------------------------------/*** Extract the file extension** @param string $filename* @return string*/public function get_extension($filename){$x = explode('.', $filename);if (count($x) === 1){return '';}$ext = ($this->file_ext_tolower) ? strtolower(end($x)) : end($x);return '.'.$ext;}// --------------------------------------------------------------------/*** Limit the File Name Length** @param string $filename* @param int $length* @return string*/public function limit_filename_length($filename, $length){if (strlen($filename) < $length){return $filename;}$ext = '';if (strpos($filename, '.') !== FALSE){$parts = explode('.', $filename);$ext = '.'.array_pop($parts);$filename = implode('.', $parts);}return substr($filename, 0, ($length - strlen($ext))).$ext;}// --------------------------------------------------------------------/*** Runs the file through the XSS clean function** This prevents people from embedding malicious code in their files.* I'm not sure that it won't negatively affect certain files in unexpected ways,* but so far I haven't found that it causes trouble.** @return string*/public function do_xss_clean(){$file = $this->file_temp;if (filesize($file) == 0){return FALSE;}if (memory_get_usage() && ($memory_limit = ini_get('memory_limit'))){$memory_limit *= 1024 * 1024;// There was a bug/behavioural change in PHP 5.2, where numbers over one million get output// into scientific notation. number_format() ensures this number is an integer// http://bugs.php.net/bug.php?id=43053$memory_limit = number_format(ceil(filesize($file) + $memory_limit), 0, '.', '');ini_set('memory_limit', $memory_limit); // When an integer is used, the value is measured in bytes. - PHP.net}// If the file being uploaded is an image, then we should have no problem with XSS attacks (in theory), but// IE can be fooled into mime-type detecting a malformed image as an html file, thus executing an XSS attack on anyone// using IE who looks at the image. It does this by inspecting the first 255 bytes of an image. To get around this// CI will itself look at the first 255 bytes of an image to determine its relative safety. This can save a lot of// processor power and time if it is actually a clean image, as it will be in nearly all instances _except_ an// attempted XSS attack.if (function_exists('getimagesize') && @getimagesize($file) !== FALSE){if (($file = @fopen($file, 'rb')) === FALSE) // "b" to force binary{return FALSE; // Couldn't open the file, return FALSE}$opening_bytes = fread($file, 256);fclose($file);// These are known to throw IE into mime-type detection chaos// <a, <body, <head, <html, <img, <plaintext, <pre, <script, <table, <title// title is basically just in SVG, but we filter it anyhow// if it's an image or no "triggers" detected in the first 256 bytes - we're goodreturn ! preg_match('/<(a|body|head|html|img|plaintext|pre|script|table|title)[\s>]/i', $opening_bytes);}if (($data = @file_get_contents($file)) === FALSE){return FALSE;}return $this->_CI->security->xss_clean($data, TRUE);}// --------------------------------------------------------------------/*** Set an error message** @param string $msg* @return CI_Upload*/public function set_error($msg, $log_level = 'error'){$this->_CI->lang->load('upload');is_array($msg) OR $msg = array($msg);foreach ($msg as $val){$msg = ($this->_CI->lang->line($val) === FALSE) ? $val : $this->_CI->lang->line($val);$this->error_msg[] = $msg;log_message($log_level, $msg);}return $this;}// --------------------------------------------------------------------/*** Display the error message** @param string $open* @param string $close* @return string*/public function display_errors($open = '<p>', $close = '</p>'){return (count($this->error_msg) > 0) ? $open.implode($close.$open, $this->error_msg).$close : '';}// --------------------------------------------------------------------/*** Prep Filename** Prevents possible script execution from Apache's handling* of files' multiple extensions.** @link http://httpd.apache.org/docs/1.3/mod/mod_mime.html#multipleext** @param string $filename* @return string*/protected function _prep_filename($filename){if ($this->mod_mime_fix === FALSE OR $this->allowed_types === '*' OR ($ext_pos = strrpos($filename, '.')) === FALSE){return $filename;}$ext = substr($filename, $ext_pos);$filename = substr($filename, 0, $ext_pos);return str_replace('.', '_', $filename).$ext;}// --------------------------------------------------------------------/*** File MIME type** Detects the (actual) MIME type of the uploaded file, if possible.* The input array is expected to be $_FILES[$field]** @param array $file* @return void*/protected function _file_mime_type($file){// We'll need this to validate the MIME info string (e.g. text/plain; charset=us-ascii)$regexp = '/^([a-z\-]+\/[a-z0-9\-\.\+]+)(;\s.+)?$/';/* Fileinfo extension - most reliable method** Unfortunately, prior to PHP 5.3 - it's only available as a PECL extension and the* more convenient FILEINFO_MIME_TYPE flag doesn't exist.*/if (function_exists('finfo_file')){$finfo = @finfo_open(FILEINFO_MIME);if (is_resource($finfo)) // It is possible that a FALSE value is returned, if there is no magic MIME database file found on the system{$mime = @finfo_file($finfo, $file['tmp_name']);finfo_close($finfo);/* According to the comments section of the PHP manual page,* it is possible that this function returns an empty string* for some files (e.g. if they don't exist in the magic MIME database)*/if (is_string($mime) && preg_match($regexp, $mime, $matches)){$this->file_type = $matches[1];return;}}}/* This is an ugly hack, but UNIX-type systems provide a "native" way to detect the file type,* which is still more secure than depending on the value of $_FILES[$field]['type'], and as it* was reported in issue #750 (https://github.com/EllisLab/CodeIgniter/issues/750) - it's better* than mime_content_type() as well, hence the attempts to try calling the command line with* three different functions.** Notes:* - the DIRECTORY_SEPARATOR comparison ensures that we're not on a Windows system* - many system admins would disable the exec(), shell_exec(), popen() and similar functions* due to security concerns, hence the function_usable() checks*/if (DIRECTORY_SEPARATOR !== '\\'){$cmd = function_exists('escapeshellarg')? 'file --brief --mime '.escapeshellarg($file['tmp_name']).' 2>&1': 'file --brief --mime '.$file['tmp_name'].' 2>&1';if (function_usable('exec')){/* This might look confusing, as $mime is being populated with all of the output when set in the second parameter.* However, we only need the last line, which is the actual return value of exec(), and as such - it overwrites* anything that could already be set for $mime previously. This effectively makes the second parameter a dummy* value, which is only put to allow us to get the return status code.*/$mime = @exec($cmd, $mime, $return_status);if ($return_status === 0 && is_string($mime) && preg_match($regexp, $mime, $matches)){$this->file_type = $matches[1];return;}}if ( ! ini_get('safe_mode') && function_usable('shell_exec')){$mime = @shell_exec($cmd);if (strlen($mime) > 0){$mime = explode("\n", trim($mime));if (preg_match($regexp, $mime[(count($mime) - 1)], $matches)){$this->file_type = $matches[1];return;}}}if (function_usable('popen')){$proc = @popen($cmd, 'r');if (is_resource($proc)){$mime = @fread($proc, 512);@pclose($proc);if ($mime !== FALSE){$mime = explode("\n", trim($mime));if (preg_match($regexp, $mime[(count($mime) - 1)], $matches)){$this->file_type = $matches[1];return;}}}}}// Fall back to the deprecated mime_content_type(), if available (still better than $_FILES[$field]['type'])if (function_exists('mime_content_type')){$this->file_type = @mime_content_type($file['tmp_name']);if (strlen($this->file_type) > 0) // It's possible that mime_content_type() returns FALSE or an empty string{return;}}$this->file_type = $file['type'];}}