How to set minimum upload size in codeigniter - codeigniter

Question

I want to set minimum width and height for uploading images in codeigniter.
The code is shown below.
$config['max_width'] = '480';
$config['max_height'] = '270';
$this->upload->do_upload()
I have set maximum cut off for this but how to set minimum ??

Answer 1

Copy your Upload.php from system/libraries and paste on application/libraries. Then,
introduce 2 new variables.
public $max_width = 0;
public $max_height = 0;
public $min_width = 0; // new
public $min_height = 0; // new
Add these to the initialize function so that you can pass values through a $config variable.
Locate is_allowed_dimensions function and modify it.
if ($this->min_width > 0 AND $D['0'] < $this->min_width)
{
return FALSE;
}
if ($this->min_height > 0 AND $D['1'] < $this->min_height)
{
return FALSE;
}
Check the upload language file and alter the upload_invalid_dimensions key accordingly to fit your case.
Have not tested this, but should work :)

Answer 2

Go to system/validation. And then open file FileRules.php
Paste this code :
public function min_dims(?string $blank, string $params): bool
{
// Grab the file name off the top of the $params
// after we split it.
$params = explode(',', $params);
$name = array_shift($params);
if (! ($files = $this->request->getFileMultiple($name))) {
$files = [$this->request->getFile($name)];
}
foreach ($files as $file) {
if ($file === null) {
return false;
}
if ($file->getError() === UPLOAD_ERR_NO_FILE) {
return true;
}
// Get Parameter sizes
$allowedWidth = $params[0] ?? 0;
$allowedHeight = $params[1] ?? 0;
// Get uploaded image size
$info = getimagesize($file->getTempName());
$fileWidth = $info[0];
$fileHeight = $info[1];
if ($fileWidth < $allowedWidth || $fileHeight < $allowedHeight) {
return false;
}
}
return true;
}
And, in your controller use min_dims[field_name,1100,1100]. The first
parameter is the field name. The second is
the width, and the third is the height
Good Luck!

Answer 3

Here is the working fix, additionally you need to specify min_height and min_width while you init
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class CI_Upload {
public $max_size = 0;
public $max_width = 0;
public $max_height = 0;
public $min_width = 0;
public $min_height = 0;
public $max_filename = 0;
public $allowed_types = "";
public $file_temp = "";
public $file_name = "";
public $orig_name = "";
public $file_type = "";
public $file_size = "";
public $file_ext = "";
public $upload_path = "";
public $overwrite = FALSE;
public $encrypt_name = FALSE;
public $is_image = FALSE;
public $image_width = '';
public $image_height = '';
public $image_type = '';
public $image_size_str = '';
public $error_msg = array();
public $mimes = array();
public $remove_spaces = TRUE;
public $xss_clean = FALSE;
public $temp_prefix = "temp_file_";
public $client_name = '';
protected $_file_name_override = '';
/**
* Constructor
*
* #access public
*/
public function __construct($props = array())
{
if (count($props) > 0)
{
$this->initialize($props);
}
log_message('debug', "Upload Class Initialized");
}
// --------------------------------------------------------------------
/**
* Initialize preferences
*
* #param array
* #return void
*/
public function initialize($config = array())
{
$defaults = array(
'max_size' => 0,
'max_width' => 0,
'max_height' => 0,
'min_width' => 0,
'min_height' => 0,
'max_filename' => 0,
'allowed_types' => "",
'file_temp' => "",
'file_name' => "",
'orig_name' => "",
'file_type' => "",
'file_size' => "",
'file_ext' => "",
'upload_path' => "",
'overwrite' => FALSE,
'encrypt_name' => FALSE,
'is_image' => FALSE,
'image_width' => '',
'image_height' => '',
'image_type' => '',
'image_size_str' => '',
'error_msg' => array(),
'mimes' => array(),
'remove_spaces' => TRUE,
'xss_clean' => FALSE,
'temp_prefix' => "temp_file_",
'client_name' => ''
);
foreach ($defaults as $key => $val)
{
if (isset($config[$key]))
{
$method = 'set_'.$key;
if (method_exists($this, $method))
{
$this->$method($config[$key]);
}
else
{
$this->$key = $config[$key];
}
}
else
{
$this->$key = $val;
}
}
// 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 = $this->file_name;
}
// --------------------------------------------------------------------
/**
* Perform the file upload
*
* #return bool
*/
public function do_upload($field = 'userfile')
{
// Is $_FILES[$field] set? If not, no reason to continue.
if ( ! isset($_FILES[$field]))
{
$this->set_error('upload_no_file_selected');
return FALSE;
}
// Is the upload path valid?
if ( ! $this->validate_upload_path())
{
// errors will already be set by validate_upload_path() so just return FALSE
return FALSE;
}
// Was the file able to be uploaded? If not, determine the reason why.
if ( ! is_uploaded_file($_FILES[$field]['tmp_name']))
{
$error = ( ! isset($_FILES[$field]['error'])) ? 4 : $_FILES[$field]['error'];
switch($error)
{
case 1: // UPLOAD_ERR_INI_SIZE
$this->set_error('upload_file_exceeds_limit');
break;
case 2: // UPLOAD_ERR_FORM_SIZE
$this->set_error('upload_file_exceeds_form_limit');
break;
case 3: // UPLOAD_ERR_PARTIAL
$this->set_error('upload_file_partial');
break;
case 4: // UPLOAD_ERR_NO_FILE
$this->set_error('upload_no_file_selected');
break;
case 6: // UPLOAD_ERR_NO_TMP_DIR
$this->set_error('upload_no_temp_directory');
break;
case 7: // UPLOAD_ERR_CANT_WRITE
$this->set_error('upload_unable_to_write_file');
break;
case 8: // UPLOAD_ERR_EXTENSION
$this->set_error('upload_stopped_by_extension');
break;
default : $this->set_error('upload_no_file_selected');
break;
}
return FALSE;
}
// Set the uploaded data as class variables
$this->file_temp = $_FILES[$field]['tmp_name'];
$this->file_size = $_FILES[$field]['size'];
$this->_file_mime_type($_FILES[$field]);
$this->file_type = preg_replace("/^(.+?);.*$/", "\\1", $this->file_type);
$this->file_type = strtolower(trim(stripslashes($this->file_type), '"'));
$this->file_name = $this->_prep_filename($_FILES[$field]['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())
{
$this->set_error('upload_invalid_filetype');
return FALSE;
}
// if we're overriding, let's now make sure the new name and type is allowed
if ($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 one
if (strpos($this->_file_name_override, '.') === FALSE)
{
$this->file_name .= $this->file_ext;
}
// An extension was provided, lets have it!
else
{
$this->file_ext = $this->get_extension($this->_file_name_override);
}
if ( ! $this->is_allowed_filetype(TRUE))
{
$this->set_error('upload_invalid_filetype');
return FALSE;
}
}
// Convert the file size to kilobytes
if ($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');
return FALSE;
}
// Are the image dimensions within the allowed size?
// Note: This can fail if the server has an open_basdir restriction.
if ( ! $this->is_allowed_dimensions())
{
$this->set_error('upload_invalid_dimensions');
return FALSE;
}
// Sanitize the file name for security
$this->file_name = $this->clean_file_name($this->file_name);
// Truncate the file name if it's too long
if ($this->max_filename > 0)
{
$this->file_name = $this->limit_filename_length($this->file_name, $this->max_filename);
}
// Remove white spaces in the name
if ($this->remove_spaces == TRUE)
{
$this->file_name = preg_replace("/\s+/", "_", $this->file_name);
}
/*
* 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 = $this->file_name;
if ($this->overwrite == FALSE)
{
$this->file_name = $this->set_filename($this->upload_path, $this->file_name);
if ($this->file_name === FALSE)
{
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 ($this->xss_clean)
{
if ($this->do_xss_clean() === FALSE)
{
$this->set_error('upload_unable_to_write_file');
return FALSE;
}
}
/*
* Move the file to the final destination
* To deal with different server configurations
* we'll attempt to use copy() first. If that fails
* we'll use move_uploaded_file(). One of the two should
* reliably work in most environments
*/
if ( ! #copy($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');
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.
*
* #return array
*/
public function data()
{
return 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' => str_replace($this->file_ext, '', $this->file_name),
'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' => $this->image_size_str,
);
}
// --------------------------------------------------------------------
/**
* Set Upload Path
*
* #param string
* #return void
*/
public function set_upload_path($path)
{
// Make sure it has a trailing slash
$this->upload_path = rtrim($path, '/').'/';
}
// --------------------------------------------------------------------
/**
* 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
* #param string
* #return string
*/
public function set_filename($path, $filename)
{
if ($this->encrypt_name == TRUE)
{
mt_srand();
$filename = md5(uniqid(mt_rand())).$this->file_ext;
}
if ( ! file_exists($path.$filename))
{
return $filename;
}
$filename = str_replace($this->file_ext, '', $filename);
$new_filename = '';
for ($i = 1; $i < 100; $i++)
{
if ( ! file_exists($path.$filename.$i.$this->file_ext))
{
$new_filename = $filename.$i.$this->file_ext;
break;
}
}
if ($new_filename == '')
{
$this->set_error('upload_bad_filename');
return FALSE;
}
else
{
return $new_filename;
}
}
// --------------------------------------------------------------------
/**
* Set Maximum File Size
*
* #param integer
* #return void
*/
public function set_max_filesize($n)
{
$this->max_size = ((int) $n < 0) ? 0: (int) $n;
}
// --------------------------------------------------------------------
/**
* Set Maximum File Name Length
*
* #param integer
* #return void
*/
public function set_max_filename($n)
{
$this->max_filename = ((int) $n < 0) ? 0: (int) $n;
}
// --------------------------------------------------------------------
/**
* Set Maximum Image Width
*
* #param integer
* #return void
*/
public function set_max_width($n)
{
$this->max_width = ((int) $n < 0) ? 0: (int) $n;
}
public function set_min_width($n)
{
$this->min_width = ((int) $n < 0) ? 0: (int) $n;
}
// --------------------------------------------------------------------
/**
* Set Maximum Image Height
*
* #param integer
* #return void
*/
public function set_max_height($n)
{
$this->max_height = ((int) $n < 0) ? 0: (int) $n;
}
public function set_min_height($n)
{
$this->min_height = ((int) $n < 0) ? 0: (int) $n;
}
// --------------------------------------------------------------------
/**
* Set Allowed File Types
*
* #param string
* #return void
*/
public function set_allowed_types($types)
{
if ( ! is_array($types) && $types == '*')
{
$this->allowed_types = '*';
return;
}
$this->allowed_types = explode('|', $types);
}
// --------------------------------------------------------------------
/**
* Set Image Properties
*
* Uses GD to determine the width/height/type of image
*
* #param string
* #return void
*/
public function set_image_properties($path = '')
{
if ( ! $this->is_image())
{
return;
}
if (function_exists('getimagesize'))
{
if (FALSE !== ($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']])) ? 'unknown' : $types[$D['2']];
$this->image_size_str = $D['3']; // string containing height and width
}
}
}
// --------------------------------------------------------------------
/**
* Set XSS Clean
*
* Enables the XSS flag so that the file that was uploaded
* will be run through the XSS filter.
*
* #param bool
* #return void
*/
public function set_xss_clean($flag = FALSE)
{
$this->xss_clean = ($flag == TRUE) ? TRUE : FALSE;
}
// --------------------------------------------------------------------
/**
* 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))
{
$this->file_type = 'image/png';
}
if (in_array($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, $img_mimes, TRUE)) ? TRUE : FALSE;
}
// --------------------------------------------------------------------
/**
* Verify that the filetype is allowed
*
* #return bool
*/
public function is_allowed_filetype($ignore_mime = FALSE)
{
if ($this->allowed_types == '*')
{
return TRUE;
}
if (count($this->allowed_types) == 0 OR ! is_array($this->allowed_types))
{
$this->set_error('upload_no_file_types');
return FALSE;
}
$ext = strtolower(ltrim($this->file_ext, '.'));
if ( ! in_array($ext, $this->allowed_types))
{
return FALSE;
}
// Images get some additional checks
$image_types = array('gif', 'jpg', 'jpeg', 'png', 'jpe');
if (in_array($ext, $image_types))
{
if (getimagesize($this->file_temp) === FALSE)
{
return FALSE;
}
}
if ($ignore_mime === TRUE)
{
return TRUE;
}
$mime = $this->mimes_types($ext);
if (is_array($mime))
{
if (in_array($this->file_type, $mime, TRUE))
{
return TRUE;
}
}
elseif ($mime == $this->file_type)
{
return TRUE;
}
return FALSE;
}
// --------------------------------------------------------------------
/**
* Verify that the file is within the allowed size
*
* #return bool
*/
public function is_allowed_filesize()
{
if ($this->max_size != 0 AND $this->file_size > $this->max_size)
{
return FALSE;
}
else
{
return TRUE;
}
}
// --------------------------------------------------------------------
/**
* 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 AND $D['0'] > $this->max_width)
{
return FALSE;
}
if ($this->max_height > 0 AND $D['1'] > $this->max_height)
{
return FALSE;
}
if ($D['0'] < $this->min_width)
{
return FALSE;
}
if ($D['1'] < $this->min_height)
{
return FALSE;
}
return TRUE;
}
return TRUE;
}
// --------------------------------------------------------------------
/**
* Validate Upload Path
*
* Verifies that it is a valid upload path with proper permissions.
*
*
* #return bool
*/
public function validate_upload_path()
{
if ($this->upload_path == '')
{
$this->set_error('upload_no_filepath');
return FALSE;
}
if (function_exists('realpath') AND #realpath($this->upload_path) !== FALSE)
{
$this->upload_path = str_replace("\\", "/", realpath($this->upload_path));
}
if ( ! #is_dir($this->upload_path))
{
$this->set_error('upload_no_filepath');
return FALSE;
}
if ( ! is_really_writable($this->upload_path))
{
$this->set_error('upload_not_writable');
return FALSE;
}
$this->upload_path = preg_replace("/(.+?)\/*$/", "\\1/", $this->upload_path);
return TRUE;
}
// --------------------------------------------------------------------
/**
* Extract the file extension
*
* #param string
* #return string
*/
public function get_extension($filename)
{
$x = explode('.', $filename);
return '.'.end($x);
}
// --------------------------------------------------------------------
/**
* Clean the file name for security
*
* #param string
* #return string
*/
public function clean_file_name($filename)
{
$bad = array(
"<!--",
"-->",
"'",
"<",
">",
'"',
'&',
'$',
'=',
';',
'?',
'/',
"%20",
"%22",
"%3c", // <
"%253c", // <
"%3e", // >
"%0e", // >
"%28", // (
"%29", // )
"%2528", // (
"%26", // &
"%24", // $
"%3f", // ?
"%3b", // ;
"%3d" // =
);
$filename = str_replace($bad, '', $filename);
return stripslashes($filename);
}
// --------------------------------------------------------------------
/**
* Limit the File Name Length
*
* #param string
* #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 void
*/
public function do_xss_clean()
{
$file = $this->file_temp;
if (filesize($file) == 0)
{
return FALSE;
}
if (function_exists('memory_get_usage') && memory_get_usage() && ini_get('memory_limit') != '')
{
$current = ini_get('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
$new_memory = number_format(ceil(filesize($file) + $current), 0, '.', '');
ini_set('memory_limit', $new_memory); // When an integer is used, the value is measured in bytes. - PHP.net
}
// If the file being uploaded is an image, then we should have no problem with XSS attacks (in theory), but
// IE can be fooled into mime-type detecting a malformed image as an html file, thus executing an XSS attack on anyone
// using IE who looks at the image. It does this by inspecting the first 255 bytes of an image. To get around this
// CI will itself look at the first 255 bytes of an image to determine its relative safety. This can save a lot of
// processor power and time if it is actually a clean image, as it will be in nearly all instances _except_ an
// attempted XSS attack.
if (function_exists('getimagesize') && #getimagesize($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 ( ! preg_match('/<(a|body|head|html|img|plaintext|pre|script|table|title)[\s>]/i', $opening_bytes))
{
return TRUE; // its an image, no "triggers" detected in the first 256 bytes, we're good
}
else
{
return FALSE;
}
}
if (($data = #file_get_contents($file)) === FALSE)
{
return FALSE;
}
$CI =& get_instance();
return $CI->security->xss_clean($data, TRUE);
}
// --------------------------------------------------------------------
/**
* Set an error message
*
* #param string
* #return void
*/
public function set_error($msg)
{
$CI =& get_instance();
$CI->lang->load('upload');
if (is_array($msg))
{
foreach ($msg as $val)
{
$msg = ($CI->lang->line($val) == FALSE) ? $val : $CI->lang->line($val);
$this->error_msg[] = $msg;
log_message('error', $msg);
}
}
else
{
$msg = ($CI->lang->line($msg) == FALSE) ? $msg : $CI->lang->line($msg);
$this->error_msg[] = $msg;
log_message('error', $msg);
}
}
// --------------------------------------------------------------------
/**
* Display the error message
*
* #param string
* #param string
* #return string
*/
public function display_errors($open = '<p>', $close = '</p>')
{
$str = '';
foreach ($this->error_msg as $val)
{
$str .= $open.$val.$close;
}
return $str;
}
// --------------------------------------------------------------------
/**
* List of Mime Types
*
* This is a list of mime types. We use it to validate
* the "allowed types" set by the developer
*
* #param string
* #return string
*/
public function mimes_types($mime)
{
global $mimes;
if (count($this->mimes) == 0)
{
if (defined('ENVIRONMENT') AND is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
{
include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
}
elseif (is_file(APPPATH.'config/mimes.php'))
{
include(APPPATH.'config//mimes.php');
}
else
{
return FALSE;
}
$this->mimes = $mimes;
unset($mimes);
}
return ( ! isset($this->mimes[$mime])) ? FALSE : $this->mimes[$mime];
}
// --------------------------------------------------------------------
/**
* Prep Filename
*
* Prevents possible script execution from Apache's handling of files multiple extensions
* http://httpd.apache.org/docs/1.3/mod/mod_mime.html#multipleext
*
* #param string
* #return string
*/
protected function _prep_filename($filename)
{
if (strpos($filename, '.') === FALSE OR $this->allowed_types == '*')
{
return $filename;
}
$parts = explode('.', $filename);
$ext = array_pop($parts);
$filename = array_shift($parts);
foreach ($parts as $part)
{
if ( ! in_array(strtolower($part), $this->allowed_types) OR $this->mimes_types(strtolower($part)) === FALSE)
{
$filename .= '.'.$part.'_';
}
else
{
$filename .= '.'.$part;
}
}
$filename .= '.'.$ext;
return $filename;
}
// --------------------------------------------------------------------
/**
* 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
* #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_exists() checks
*/
if (DIRECTORY_SEPARATOR !== '\\')
{
$cmd = 'file --brief --mime ' . escapeshellarg($file['tmp_name']) . ' 2>&1';
if (function_exists('exec'))
{
/* This might look confusing, as $mime is being populated with all of the output when set in the second parameter.
* However, we only neeed 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 ( (bool) #ini_get('safe_mode') === FALSE && function_exists('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_exists('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'];
}
// --------------------------------------------------------------------
}