我在下面的代码中遇到以下错误：
遇到PHP错误 严重程度：通知
消息：只能通过引用传递变量
文件名：codeigniter / Common.php
请帮助我。
http://codeigniter.com/user_guide/license.html * @link http://codeigniter.com * @自1.0版起 * @filesource * /
// ------------------------------------------------------------------------
/**
* Determines if the current version of PHP is greater then the supplied value
*
* Since there are a few places where we conditionally test for PHP > 5
* we'll set a static variable.
*
* @access public
* @param string
* @return bool
*/
function is_php($version = '5.0.0')
{
static $_is_php;
$version = (string)$version;
if ( ! isset($_is_php[$version]))
{
$_is_php[$version] = (version_compare(PHP_VERSION, $version) < 0) ? FALSE : TRUE;
}
return $_is_php[$version];
}
// ------------------------------------------------------------------------
/**
* Tests for file writability
*
* is_writable() returns TRUE on Windows servers when you really can't write to
* the file, based on the read-only attribute. is_writable() is also unreliable
* on Unix servers if safe_mode is on.
*
* @access private
* @return void
*/
function is_really_writable($file)
{
// If we're on a Unix server with safe_mode off we call is_writable
if (DIRECTORY_SEPARATOR == '/' AND @ini_get("safe_mode") == FALSE)
{
return is_writable($file);
}
// For windows servers and safe_mode "on" installations we'll actually
// write a file then read it. Bah...
if (is_dir($file))
{
$file = rtrim($file, '/').'/'.md5(rand(1,100));
if (($fp = @fopen($file, FOPEN_WRITE_CREATE)) === FALSE)
{
return FALSE;
}
fclose($fp);
@chmod($file, DIR_WRITE_MODE);
@unlink($file);
return TRUE;
}
elseif (($fp = @fopen($file, FOPEN_WRITE_CREATE)) === FALSE)
{
return FALSE;
}
fclose($fp);
return TRUE;
}
// ------------------------------------------------------------------------
/**
* Class registry
*
* This function acts as a singleton. If the requested class does not
* exist it is instantiated and set to a static variable. If it has
* previously been instantiated the variable is returned.
*
* @access public
* @param string the class name being requested
* @param bool optional flag that lets classes get loaded but not instantiated
* @return object
*/
function &load_class($class, $instantiate = TRUE)
{
static $objects = array();
// Does the class exist? If so, we're done...
if (isset($objects[$class]))
{
return $objects[$class];
}
// If the requested class does not exist in the application/libraries
// folder we'll load the native class from the system/libraries folder.
if (file_exists(APPPATH.'libraries/'.config_item('subclass_prefix').$class.EXT))
{
require(BASEPATH.'libraries/'.$class.EXT);
require(APPPATH.'libraries/'.config_item('subclass_prefix').$class.EXT);
$is_subclass = TRUE;
}
else
{
if (file_exists(APPPATH.'libraries/'.$class.EXT))
{
require(APPPATH.'libraries/'.$class.EXT);
$is_subclass = FALSE;
}
else
{
require(BASEPATH.'libraries/'.$class.EXT);
$is_subclass = FALSE;
}
}
if ($instantiate == FALSE)
{
$objects[$class] = TRUE;
return $objects[$class];
}
if ($is_subclass == TRUE)
{
$name = config_item('subclass_prefix').$class;
$objects[$class] =& instantiate_class(new $name());
return $objects[$class];
}
$name = ($class != 'Controller') ? 'CI_'.$class : $class;
$objects[$class] =& instantiate_class(new $name());
return $objects[$class];
}
/**
* Instantiate Class
*
* Returns a new class object by reference, used by load_class() and the DB class.
* Required to retain PHP 4 compatibility and also not make PHP 5.3 cry.
*
* Use: $obj =& instantiate_class(new Foo());
*
* @access public
* @param object
* @return object
*/
function &instantiate_class(&$class_object)
{
return $class_object;
}
/**
* Loads the main config.php file
*
* @access private
* @return array
*/
function &get_config()
{
static $main_conf;
if ( ! isset($main_conf))
{
if ( ! file_exists(APPPATH.'config/config'.EXT))
{
exit('The configuration file config'.EXT.' does not exist.');
}
require(APPPATH.'config/config'.EXT);
if ( ! isset($config) OR ! is_array($config))
{
exit('Your config file does not appear to be formatted correctly.');
}
$main_conf[0] =& $config;
}
return $main_conf[0];
}
/**
* Gets a config item
*
* @access public
* @return mixed
*/
function config_item($item)
{
static $config_item = array();
if ( ! isset($config_item[$item]))
{
$config =& get_config();
if ( ! isset($config[$item]))
{
return FALSE;
}
$config_item[$item] = $config[$item];
}
return $config_item[$item];
}
/**
* Error Handler
*
* This function lets us invoke the exception class and
* display errors using the standard error template located
* in application/errors/errors.php
* This function will send the error page directly to the
* browser and exit.
*
* @access public
* @return void
*/
function show_error($message, $status_code = 500)
{
$error =& load_class('Exceptions');
echo $error->show_error('An Error Was Encountered', $message, 'error_general', $status_code);
exit;
}
/**
* 404 Page Handler
*
* This function is similar to the show_error() function above
* However, instead of the standard error template it displays
* 404 errors.
*
* @access public
* @return void
*/
function show_404($page = '')
{
$error =& load_class('Exceptions');
$error->show_404($page);
exit;
}
/**
* Error Logging Interface
*
* We use this as a simple mechanism to access the logging
* class and send messages to be logged.
*
* @access public
* @return void
*/
function log_message($level = 'error', $message, $php_error = FALSE)
{
static $LOG;
$config =& get_config();
if ($config['log_threshold'] == 0)
{
return;
}
$LOG =& load_class('Log');
$LOG->write_log($level, $message, $php_error);
}
/**
* Set HTTP Status Header
*
* @access public
* @param int the status code
* @param string
* @return void
*/
function set_status_header($code = 200, $text = '')
{
$stati = array(
200 => 'OK',
201 => 'Created',
202 => 'Accepted',
203 => 'Non-Authoritative Information',
204 => 'No Content',
205 => 'Reset Content',
206 => 'Partial Content',
300 => 'Multiple Choices',
301 => 'Moved Permanently',
302 => 'Found',
304 => 'Not Modified',
305 => 'Use Proxy',
307 => 'Temporary Redirect',
400 => 'Bad Request',
401 => 'Unauthorized',
403 => 'Forbidden',
404 => 'Not Found',
405 => 'Method Not Allowed',
406 => 'Not Acceptable',
407 => 'Proxy Authentication Required',
408 => 'Request Timeout',
409 => 'Conflict',
410 => 'Gone',
411 => 'Length Required',
412 => 'Precondition Failed',
413 => 'Request Entity Too Large',
414 => 'Request-URI Too Long',
415 => 'Unsupported Media Type',
416 => 'Requested Range Not Satisfiable',
417 => 'Expectation Failed',
500 => 'Internal Server Error',
501 => 'Not Implemented',
502 => 'Bad Gateway',
503 => 'Service Unavailable',
504 => 'Gateway Timeout',
505 => 'HTTP Version Not Supported'
);
if ($code == '' OR ! is_numeric($code))
{
show_error('Status codes must be numeric', 500);
}
if (isset($stati[$code]) AND $text == '')
{
$text = $stati[$code];
}
if ($text == '')
{
show_error('No status text available. Please check your status code number or supply your own message text.', 500);
}
$server_protocol = (isset($_SERVER['SERVER_PROTOCOL'])) ? $_SERVER['SERVER_PROTOCOL'] : FALSE;
if (substr(php_sapi_name(), 0, 3) == 'cgi')
{
header("Status: {$code} {$text}", TRUE);
}
elseif ($server_protocol == 'HTTP/1.1' OR $server_protocol == 'HTTP/1.0')
{
header($server_protocol." {$code} {$text}", TRUE, $code);
}
else
{
header("HTTP/1.1 {$code} {$text}", TRUE, $code);
}
}
/**
* Exception Handler
*
* This is the custom exception handler that is declaired at the top
* of Codeigniter.php. The main reason we use this is permit
* PHP errors to be logged in our own log files since we may
* not have access to server logs. Since this function
* effectively intercepts PHP errors, however, we also need
* to display errors based on the current error_reporting level.
* We do that with the use of a PHP error template.
*
* @access private
* @return void
*/
function _exception_handler($severity, $message, $filepath, $line)
{
// We don't bother with "strict" notices since they will fill up
// the log file with information that isn't normally very
// helpful. For example, if you are running PHP 5 and you
// use version 4 style class functions (without prefixes
// like "public", "private", etc.) you'll get notices telling
// you that these have been deprecated.
if ($severity == E_STRICT)
{
return;
}
$error =& load_class('Exceptions');
// Should we display the error?
// We'll get the current error_reporting level and add its bits
// with the severity bits to find out.
if (($severity & error_reporting()) == $severity)
{
$error->show_php_error($severity, $message, $filepath, $line);
}
// Should we log the error? No? We're done...
$config =& get_config();
if ($config['log_threshold'] == 0)
{
return;
}
$error->log_exception($severity, $message, $filepath, $line);
}
/* End of file Common.php */
/* Location: ./system/codeigniter/Common.php */