Kohana

Complexity

Total Complexity

219

Size/Duplication

Total Lines	1463
Duplicated Lines	1.23 %

Coupling/Cohesion

Components	2
Dependencies	4

Importance

Changes	4
Bugs	2	Features	0

28 Methods

Rating	Name	Duplication	Size	Complexity
C	setup()	0	129	11
C	instance()	0	73	10
A	include_paths()	0	19	4
B	config()	0	29	6
B	config_set()	0	32	5
D	config_load()	0	39	9
A	config_clear()	0	10	2
A	log()	0	11	2
B	log_save()	0	32	5
A	log_directory()	0	19	4
C	cache()	0	39	7
B	cache_save()	0	28	5
A	output_buffer()	0	13	2
A	close_buffers()	0	14	4
A	shutdown()	0	11	1
C	render()	0	70	15
A	show_404()	0	4	1
F	exception_handler()	0	111	23
C	auto_load()	0	66	13
C	find_file()	0	67	12
C	list_files()	0	36	8
C	lang()	0	53	12
B	key_string()	0	29	6
C	key_string_set()	0	54	10
F	user_agent()	18	90	25
A	debug()	0	16	3
C	backtrace()	0	51	10
B	internal_cache_save()	0	24	4

<?php defined('SYSPATH') or die('No direct access allowed.');
/**
 * Provides Kohana-specific helper functions. This is where the magic happens!
 *
 * $Id: Kohana.php 4372 2009-05-28 17:00:34Z ixmatus $
 *
 * @package    Core
 * @author     Kohana Team
 * @copyright  (c) 2007-2008 Kohana Team
 * @license    http://kohanaphp.com/license.html
 */
final class Kohana
{

    // The singleton instance of the controller
    public static $instance;

    // Output buffering level
    private static $buffer_level;

    // Will be set to TRUE when an exception is caught
    public static $has_error = false;

    // The final output that will displayed by Kohana
    public static $output = '';

    // The current user agent
    public static $user_agent;

    // The current locale
    public static $locale;

    // Configuration
    private static $configuration;

    // Include paths
    private static $include_paths;

    // Logged messages
    private static $log;

    // Cache lifetime
    private static $cache_lifetime;

    // Log levels
    private static $log_levels = array(
        'error' => 1,
        'alert' => 2,
        'info'  => 3,
        'debug' => 4,
    );

    // Internal caches and write status
    private static $internal_cache = array();
    private static $write_cache;
    private static $internal_cache_path;
    private static $internal_cache_key;
    private static $internal_cache_encrypt;

    /**
     * Sets up the PHP environment. Adds error/exception handling, output
     * buffering, and adds an auto-loading method for loading classes.
     *
     * This method is run immediately when this file is loaded, and is
     * benchmarked as environment_setup.
     *
     * For security, this function also destroys the $_REQUEST global variable.
     * Using the proper global (GET, POST, COOKIE, etc) is inherently more secure.
     * The recommended way to fetch a global variable is using the Input library.
     * @see http://www.php.net/globals
     *
     * @return  void
     */
    public static function setup()

setup uses the super-global variable $_SERVER which is generally not recommended.

    {
        static $run;

        // This function can only be run once
        if ($run === true) {
            return;
        }

        // Start the environment setup benchmark
        Benchmark::start(SYSTEM_BENCHMARK.'_environment_setup');

        // Define Kohana error constant
        define('E_KOHANA', 42);

        // Define 404 error constant
        define('E_PAGE_NOT_FOUND', 43);

        // Define database error constant
        define('E_DATABASE_ERROR', 44);

        if (self::$cache_lifetime = self::config('core.internal_cache')) {
            // Are we using encryption for caches?
            self::$internal_cache_encrypt    = self::config('core.internal_cache_encrypt');

            if (self::$internal_cache_encrypt===true) {
                self::$internal_cache_key = self::config('core.internal_cache_key');

                // Be sure the key is of acceptable length for the mcrypt algorithm used
                self::$internal_cache_key = substr(self::$internal_cache_key, 0, 24);
            }

            // Set the directory to be used for the internal cache
            if (! self::$internal_cache_path = self::config('core.internal_cache_path')) {
                self::$internal_cache_path = APPPATH.'cache/';
            }

            // Load cached configuration and language files
            self::$internal_cache['configuration'] = self::cache('configuration', self::$cache_lifetime);
            self::$internal_cache['language']      = self::cache('language', self::$cache_lifetime);

            // Load cached file paths
            self::$internal_cache['find_file_paths'] = self::cache('find_file_paths', self::$cache_lifetime);

            // Enable cache saving
            Event::add('system.shutdown', array(__CLASS__, 'internal_cache_save'));
        }

        // Disable notices and "strict" errors
        $ER = error_reporting(~E_NOTICE & ~E_STRICT);

Avoid variables with short names like $ER. Configured minimum length is 3.

        // Set the user agent
        self::$user_agent = (! empty($_SERVER['HTTP_USER_AGENT']) ? trim($_SERVER['HTTP_USER_AGENT']) : '');

        if (function_exists('date_default_timezone_set')) {
            $timezone = self::config('locale.timezone');

            // Set default timezone, due to increased validation of date settings
            // which cause massive amounts of E_NOTICEs to be generated in PHP 5.2+
            date_default_timezone_set(empty($timezone) ? date_default_timezone_get() : $timezone);
        }

        // Restore error reporting
        error_reporting($ER);

        // Start output buffering
        ob_start(array(__CLASS__, 'output_buffer'));

        // Save buffering level
        self::$buffer_level = ob_get_level();

        // Set autoloader
        spl_autoload_register(array('Kohana', 'auto_load'));

        // Set error handler
        set_error_handler(array('Kohana', 'exception_handler'));

        // Set exception handler
        set_exception_handler(array('Kohana', 'exception_handler'));

        // Send default text/html UTF-8 header
        header('Content-Type: text/html; charset=UTF-8');

        // Load locales
        $locales = self::config('locale.language');

        // Make first locale UTF-8
        $locales[0] .= '.UTF-8';

        // Set locale information
        self::$locale = setlocale(LC_ALL, $locales);

        if (self::$configuration['core']['log_threshold'] > 0) {
            // Set the log directory
            self::log_directory(self::$configuration['core']['log_directory']);

            // Enable log writing at shutdown
            register_shutdown_function(array(__CLASS__, 'log_save'));
        }

        // Enable Kohana routing
        Event::add('system.routing', array('Router', 'find_uri'));
        Event::add('system.routing', array('Router', 'setup'));

        // Enable Kohana controller initialization
        Event::add('system.execute', array('Kohana', 'instance'));

        // Enable Kohana 404 pages
        Event::add('system.404', array('Kohana', 'show_404'));

        // Enable Kohana output handling
        Event::add('system.shutdown', array('Kohana', 'shutdown'));

        if (self::config('core.enable_hooks') === true) {
            // Find all the hook files
            $hooks = self::list_files('hooks', true);

            foreach ($hooks as $file) {
                // Load the hook
                include $file;
            }
        }

        // Setup is complete, prevent it from being run again
        $run = true;

        // Stop the environment setup routine
        Benchmark::stop(SYSTEM_BENCHMARK.'_environment_setup');
    }

    /**
     * Loads the controller and initializes it. Runs the pre_controller,
     * post_controller_constructor, and post_controller events. Triggers
     * a system.404 event when the route cannot be mapped to a controller.
     *
     * This method is benchmarked as controller_setup and controller_execution.
     *
     * @return  object  instance of controller
     */
    public static function & instance()
    {
        if (self::$instance === null) {
            Benchmark::start(SYSTEM_BENCHMARK.'_controller_setup');

            // Include the Controller file
            require Router::$controller_path;

            try {
                // Start validation of the controller
                $class = new ReflectionClass(ucfirst(Router::$controller).'_Controller');
            } catch (ReflectionException $e) {
                // Controller does not exist
                Event::run('system.404');
            }

            if ($class->isAbstract() or (IN_PRODUCTION and $class->getConstant('ALLOW_PRODUCTION') == false)) {
                // Controller is not allowed to run in production
                Event::run('system.404');
            }

            // Run system.pre_controller
            Event::run('system.pre_controller');

            // Create a new controller instance
            $controller = $class->newInstance();

            // Controller constructor has been executed
            Event::run('system.post_controller_constructor');

            try {
                // Load the controller method
                $method = $class->getMethod(Router::$method);

                // Method exists
                if (Router::$method[0] === '_') {
                    // Do not allow access to hidden methods
                    Event::run('system.404');
                }

                if ($method->isProtected() or $method->isPrivate()) {
                    // Do not attempt to invoke protected methods
                    throw new ReflectionException('protected controller method');
                }

                // Default arguments
                $arguments = Router::$arguments;
            } catch (ReflectionException $e) {
                // Use __call instead
                $method = $class->getMethod('__call');

                // Use arguments in __call format
                $arguments = array(Router::$method, Router::$arguments);
            }

            // Stop the controller setup benchmark
            Benchmark::stop(SYSTEM_BENCHMARK.'_controller_setup');

            // Start the controller execution benchmark
            Benchmark::start(SYSTEM_BENCHMARK.'_controller_execution');

            // Execute the controller method
            $method->invokeArgs($controller, $arguments);

            // Controller method has been executed
            Event::run('system.post_controller');

            // Stop the controller execution benchmark
            Benchmark::stop(SYSTEM_BENCHMARK.'_controller_execution');
        }

        return self::$instance;
    }

    /**
     * Get all include paths. APPPATH is the first path, followed by module
     * paths in the order they are configured, follow by the SYSPATH.
     *
     * @param   boolean  re-process the include paths
     * @return  array
     */
    public static function include_paths($process = false)
    {
        if ($process === true) {
            // Add APPPATH as the first path
            self::$include_paths = array(APPPATH);

            foreach (self::$configuration['core']['modules'] as $path) {
                if ($path = str_replace('\\', '/', realpath($path))) {
                    // Add a valid path
                    self::$include_paths[] = $path.'/';
                }
            }

            // Add SYSPATH as the last path
            self::$include_paths[] = SYSPATH;
        }

        return self::$include_paths;
    }

    /**
     * Get a config item or group.
     *
     * @param   string   item name
     * @param   boolean  force a forward slash (/) at the end of the item
     * @param   boolean  is the item required?
     * @return  string
     */
    public static function config($key, $slash = false, $required = true)
    {
        if (self::$configuration === null) {
            // Load core configuration
            self::$configuration['core'] = self::config_load('core');

            // Re-parse the include paths
            self::include_paths(true);
        }

        // Get the group name from the key
        $group = explode('.', $key, 2);
        $group = $group[0];

        if (! isset(self::$configuration[$group])) {
            // Load the configuration group
            self::$configuration[$group] = self::config_load($group, $required);
        }

        // Get the value of the key string
        $value = self::key_string(self::$configuration, $key);

        if ($slash === true and is_string($value) and $value !== '') {
            // Force the value to end with "/"
            $value = rtrim($value, '/').'/';
        }

        return $value;
    }

    /**
     * Sets a configuration item, if allowed.
     *
     * @param   string   config key string
     * @param   string   config value
     * @return  boolean
     */
    public static function config_set($key, $value)
    {
        // Do this to make sure that the config array is already loaded
        self::config($key);

        if (substr($key, 0, 7) === 'routes.') {
            // Routes cannot contain sub keys due to possible dots in regex
            $keys = explode('.', $key, 2);
        } else {
            // Convert dot-noted key string to an array
            $keys = explode('.', $key);
        }

        // Used for recursion
        $conf =& self::$configuration;
        $last = count($keys) - 1;

        foreach ($keys as $i => $k) {
            if ($i === $last) {
                $conf[$k] = $value;
            } else {
                $conf =& $conf[$k];
            }
        }

        if ($key === 'core.modules') {
            // Reprocess the include paths
            self::include_paths(true);
        }

        return true;
    }

    /**
     * Load a config file.
     *
     * @param   string   config filename, without extension
     * @param   boolean  is the file required?
     * @return  array
     */
    public static function config_load($name, $required = true)
    {
        if ($name === 'core') {
            // Load the application configuration file
            require APPPATH.'config/config'.EXT;

            if (! isset($config['site_domain'])) {

The variable $config seems to never exist, and therefore isset should always return false. Did you maybe rename this variable?

                // Invalid config file
                die('Your Kohana application configuration file is not valid.');

The method config_load() contains an exit expression.

            }

            return $config;
        }

        if (isset(self::$internal_cache['configuration'][$name])) {
            return self::$internal_cache['configuration'][$name];
        }

        // Load matching configs
        $configuration = array();

        if ($files = self::find_file('config', $name, $required)) {
            foreach ($files as $file) {

The expression $files of type string is not traversable.

                require $file;

                if (isset($config) and is_array($config)) {
                    // Merge in configuration
                    $configuration = array_merge($configuration, $config);
                }
            }
        }

        if (! isset(self::$write_cache['configuration'])) {
            // Cache has changed
            self::$write_cache['configuration'] = true;
        }

        return self::$internal_cache['configuration'][$name] = $configuration;
    }

    /**
     * Clears a config group from the cached configuration.
     *
     * @param   string  config group
     * @return  void
     */
    public static function config_clear($group)
    {
        // Remove the group from config
        unset(self::$configuration[$group], self::$internal_cache['configuration'][$group]);

        if (! isset(self::$write_cache['configuration'])) {
            // Cache has changed
            self::$write_cache['configuration'] = true;
        }
    }

    /**
     * Add a new message to the log.
     *
     * @param   string  type of message
     * @param   string  message text
     * @return  void
     */
    public static function log($type, $message)
    {
        if (self::$log_levels[$type] <= self::$configuration['core']['log_threshold']) {
            $message = array(date('Y-m-d H:i:s P'), $type, $message);

            // Run the system.log event
            Event::run('system.log', $message);

            self::$log[] = $message;
        }
    }

    /**
     * Save all currently logged messages.
     *
     * @return  void
     */
    public static function log_save()
    {
        if (empty(self::$log) or self::$configuration['core']['log_threshold'] < 1) {
            return;
        }

        // Filename of the log
        $filename = self::log_directory().date('Y-m-d').'.log'.EXT;

        if (! is_file($filename)) {
            // Write the SYSPATH checking header
            file_put_contents($filename,
                '<?php defined(\'SYSPATH\') or die(\'No direct script access.\'); ?>'.PHP_EOL.PHP_EOL);

            // Prevent external writes
            chmod($filename, 0644);
        }

        // Messages to write
        $messages = array();

        do {
            // Load the next mess
            list($date, $type, $text) = array_shift(self::$log);

            // Add a new message line
            $messages[] = $date.' --- '.$type.': '.$text;
        } while (! empty(self::$log));

        // Write messages to log file
        file_put_contents($filename, implode(PHP_EOL, $messages).PHP_EOL, FILE_APPEND);
    }

    /**
     * Get or set the logging directory.
     *
     * @param   string  new log directory
     * @return  string
     */
    public static function log_directory($dir = null)
    {
        static $directory;

        if (! empty($dir)) {
            // Get the directory path
            $dir = realpath($dir);

            if (is_dir($dir) and is_writable($dir)) {
                // Change the log directory
                $directory = str_replace('\\', '/', $dir).'/';
            } else {
                // Log directory is invalid
                throw new Kohana_Exception('core.log_dir_unwritable', $dir);
            }
        }

        return $directory;
    }

    /**
     * Load data from a simple cache file. This should only be used internally,
     * and is NOT a replacement for the Cache library.
     *
     * @param   string   unique name of cache
     * @param   integer  expiration in seconds
     * @param string $name
     * @param string $lifetime
     * @return  mixed
     */
    public static function cache($name, $lifetime)
    {
        if ($lifetime > 0) {
            $path = self::$internal_cache_path.'kohana_'.$name;

            if (is_file($path)) {
                // Check the file modification time
                if ((time() - filemtime($path)) < $lifetime) {
                    // Cache is valid! Now, do we need to decrypt it?
                    if (self::$internal_cache_encrypt===true) {
                        $data        = file_get_contents($path);

                        $iv_size    = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
                        $iv            = mcrypt_create_iv($iv_size, MCRYPT_RAND);

Avoid variables with short names like $iv. Configured minimum length is 3.

                        $decrypted_text    = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, self::$internal_cache_key, $data, MCRYPT_MODE_ECB, $iv);

                        $cache    = unserialize($decrypted_text);

                        // If the key changed, delete the cache file
                        if (!$cache) {
                            unlink($path);
                        }

                        // If cache is false (as above) return NULL, otherwise, return the cache
                        return ($cache ? $cache : null);
                    } else {
                        return unserialize(file_get_contents($path));
                    }
                } else {
                    // Cache is invalid, delete it
                    unlink($path);
                }
            }
        }

        // No cache found
        return null;
    }

    /**
     * Save data to a simple cache file. This should only be used internally, and
     * is NOT a replacement for the Cache library.
     *
     * @param   string   cache name
     * @param   mixed    data to cache
     * @param   integer  expiration in seconds
     * @return  boolean
     */
    public static function cache_save($name, $data, $lifetime)
    {
        if ($lifetime < 1) {
            return false;
        }

        $path = self::$internal_cache_path.'kohana_'.$name;

        if ($data === null) {
            // Delete cache
            return (is_file($path) and unlink($path));
        } else {
            // Using encryption? Encrypt the data when we write it
            if (self::$internal_cache_encrypt===true) {
                // Encrypt and write data to cache file
                $iv_size    = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
                $iv            = mcrypt_create_iv($iv_size, MCRYPT_RAND);

Avoid variables with short names like $iv. Configured minimum length is 3.

                // Serialize and encrypt!
                $encrypted_text    = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, self::$internal_cache_key, serialize($data), MCRYPT_MODE_ECB, $iv);

                return (bool) file_put_contents($path, $encrypted_text);
            } else {
                // Write data to cache file
                return (bool) file_put_contents($path, serialize($data));
            }
        }
    }

    /**
     * Kohana output handler. Called during ob_clean, ob_flush, and their variants.
     *
     * @param   string  current output buffer
     * @return  string
     */
    public static function output_buffer($output)
    {
        // Could be flushing, so send headers first
        if (! Event::has_run('system.send_headers')) {
            // Run the send_headers event
            Event::run('system.send_headers');
        }

        self::$output    = $output;

        // Set and return the final output
        return self::$output;
    }

    /**
     * Closes all open output buffers, either by flushing or cleaning, and stores the Kohana
     * output buffer for display during shutdown.
     *
     * @param   boolean  disable to clear buffers, rather than flushing
     * @return  void
     */
    public static function close_buffers($flush = true)
    {
        if (ob_get_level() >= self::$buffer_level) {
            // Set the close function
            $close = ($flush === true) ? 'ob_end_flush' : 'ob_end_clean';
            if (ob_get_level() >= self::$buffer_level) {
                // Flush or clean the buffer
                $close();
            }

            // Store the Kohana output buffer
            ob_end_clean();
        }
    }

    /**
     * Triggers the shutdown of Kohana by closing the output buffer, runs the system.display event.
     *
     * @return  void
     */
    public static function shutdown()
    {
        // Close output buffers
        //self::close_buffers(TRUE);

        // Run the output event
        Event::run('system.display', self::$output);

        // Render the final output
        self::render(self::$output);
    }

    /**
     * Inserts global Kohana variables into the generated output and prints it.
     *
     * @param   string  final output that will displayed
     * @return  void
     */
    public static function render($output)

render uses the super-global variable $_SERVER which is generally not recommended.

    {
        if (self::config('core.render_stats') === true) {
            // Fetch memory usage in MB
            $memory = function_exists('memory_get_usage') ? (memory_get_usage() / 1024 / 1024) : 0;

            // Fetch benchmark for page execution time
            $benchmark = Benchmark::get(SYSTEM_BENCHMARK.'_total_execution');

            // Replace the global template variables
            $output = str_replace(
                array(
                    '{kohana_version}',
                    '{kohana_codename}',
                    '{execution_time}',
                    '{memory_usage}',
                    '{included_files}',
                ),
                array(
                    KOHANA_VERSION,
                    KOHANA_CODENAME,
                    $benchmark['time'],
                    number_format($memory, 2).'MB',
                    count(get_included_files()),
                ),
                $output
            );
        }

        if ($level = self::config('core.output_compression') and ini_get('output_handler') !== 'ob_gzhandler' and (int) ini_get('zlib.output_compression') === 0) {
            if ($level < 1 or $level > 9) {
                // Normalize the level to be an integer between 1 and 9. This
                // step must be done to prevent gzencode from triggering an error
                $level = max(1, min($level, 9));
            }

            if (stripos(@$_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== false) {
                $compress = 'gzip';
            } elseif (stripos(@$_SERVER['HTTP_ACCEPT_ENCODING'], 'deflate') !== false) {
                $compress = 'deflate';
            }
        }

        if (isset($compress) and $level > 0) {
            switch ($compress) {
                case 'gzip':
                    // Compress output using gzip
                    $output = gzencode($output, $level);
                break;
                case 'deflate':
                    // Compress output using zlib (HTTP deflate)
                    $output = gzdeflate($output, $level);
                break;
            }

            // This header must be sent with compressed content to prevent
            // browser caches from breaking
            header('Vary: Accept-Encoding');

            // Send the content encoding header
            header('Content-Encoding: '.$compress);

            // Sending Content-Length in CGI can result in unexpected behavior
            if (stripos(PHP_SAPI, 'cgi') === false) {
                header('Content-Length: '.strlen($output));
            }
        }

        echo $output;
    }

    /**
     * Displays a 404 page.
     *
     * @throws  Kohana_404_Exception
     * @param   string  URI of page
     * @param   string  custom template
     * @return  void

Consider making the return type a bit more specific; maybe use NoType.

     */
    public static function show_404($page = false, $template = false)
    {
        throw new Kohana_404_Exception($page, $template);
    }

    /**
     * Dual-purpose PHP error and exception handler. Uses the kohana_error_page
     * view to display the message.
     *
     * @param   integer|object  exception object or error code
     * @param   string          error message
     * @param   string          filename
     * @param   integer         line number
     * @return  void
     */
    public static function exception_handler($exception, $message = null, $file = null, $line = null)
    {
        try {
            // PHP errors have 5 args, always
            $PHP_ERROR = (func_num_args() === 5);

            // Test to see if errors should be displayed
            if ($PHP_ERROR and (error_reporting() & $exception) === 0) {
                return;
            }

            // This is useful for hooks to determine if a page has an error
            self::$has_error = true;

            // Error handling will use exactly 5 args, every time
            if ($PHP_ERROR) {
                $code     = $exception;
                $type     = 'PHP Error';
                $template = 'kohana_error_page';
            } else {
                $code     = $exception->getCode();
                $type     = get_class($exception);
                $message  = $exception->getMessage();
                $file     = $exception->getFile();
                $line     = $exception->getLine();
                $template = ($exception instanceof Kohana_Exception) ? $exception->getTemplate() : 'kohana_error_page';
            }

            if (is_numeric($code)) {
                $codes = self::lang('errors');

                if (! empty($codes[$code])) {
                    list($level, $error, $description) = $codes[$code];
                } else {
                    $level = 1;
                    $error = $PHP_ERROR ? 'Unknown Error' : get_class($exception);
                    $description = '';
                }
            } else {
                // Custom error message, this will never be logged
                $level = 5;
                $error = $code;
                $description = '';
            }

            // Remove the DOCROOT from the path, as a security precaution
            $file = str_replace('\\', '/', realpath($file));
            $file = preg_replace('|^'.preg_quote(DOCROOT).'|', '', $file);

            if ($level <= self::$configuration['core']['log_threshold']) {
                // Log the error
                self::log('error', self::lang('core.uncaught_exception', $type, $message, $file, $line));
            }

            if ($PHP_ERROR) {
                $description = self::lang('errors.'.E_RECOVERABLE_ERROR);
                $description = is_array($description) ? $description[2] : '';

                if (! headers_sent()) {
                    // Send the 500 header
                    header('HTTP/1.1 500 Internal Server Error');
                }
            } else {
                if (method_exists($exception, 'sendHeaders') and ! headers_sent()) {
                    // Send the headers if they have not already been sent
                    $exception->sendHeaders();
                }
            }

            // Close all output buffers except for Kohana
            while (ob_get_level() > self::$buffer_level) {
                ob_end_clean();
            }

            // Test if display_errors is on
            if (self::$configuration['core']['display_errors'] === true) {
                if (! IN_PRODUCTION and $line != false) {
                    // Remove the first entry of debug_backtrace(), it is the exception_handler call
                    $trace = $PHP_ERROR ? array_slice(debug_backtrace(), 1) : $exception->getTrace();

                    // Beautify backtrace
                    $trace = self::backtrace($trace);
                }

                // Load the error
                require self::find_file('views', empty($template) ? 'kohana_error_page' : $template);
            } else {
                // Get the i18n messages
                $error   = self::lang('core.generic_error');
                $message = self::lang('core.errors_disabled', url::site(), url::site(Router::$current_uri));

                // Load the errors_disabled view
                require self::find_file('views', 'kohana_error_disabled');
            }

            if (! Event::has_run('system.shutdown')) {
                // Run the shutdown even to ensure a clean exit
                Event::run('system.shutdown');
            }

            // Turn off error reporting
            error_reporting(0);
            exit;

The method exception_handler() contains an exit expression.

        } catch (Exception $e) {
            if (IN_PRODUCTION) {
                die('Fatal Error');

The method exception_handler() contains an exit expression.

            } else {
                die('Fatal Error: '.$e->getMessage().' File: '.$e->getFile().' Line: '.$e->getLine());

The method exception_handler() contains an exit expression.

            }
        }
    }

    /**
     * Provides class auto-loading.
     *
     * @throws  Kohana_Exception
     * @param   string  name of class
     * @param string $class
     * @return  bool
     */
    public static function auto_load($class)
    {
        if (class_exists($class, false)) {
            return true;
        }

        if (($suffix = strrpos($class, '_')) > 0) {
            // Find the class suffix
            $suffix = substr($class, $suffix + 1);
        } else {
            // No suffix
            $suffix = false;
        }

        if ($suffix === 'Core') {
            $type = 'libraries';
            $file = substr($class, 0, -5);
        } elseif ($suffix === 'Controller') {
            $type = 'controllers';
            // Lowercase filename
            $file = strtolower(substr($class, 0, -11));
        } elseif ($suffix === 'Model') {
            $type = 'models';
            // Lowercase filename
            $file = strtolower(substr($class, 0, -6));
        } elseif ($suffix === 'Driver') {
            $type = 'libraries/drivers';
            $file = str_replace('_', '/', substr($class, 0, -7));
        } else {
            // This could be either a library or a helper, but libraries must
            // always be capitalized, so we check if the first character is
            // uppercase. If it is, we are loading a library, not a helper.
            $type = ($class[0] < 'a') ? 'libraries' : 'helpers';
            $file = $class;
        }

        if ($filename = self::find_file($type, $file)) {
            // Load the class
            require $filename;
        } else {
            // The class could not be found
            return false;
        }

        if ($filename = self::find_file($type, self::$configuration['core']['extension_prefix'].$class)) {
            // Load the class extension
            require $filename;
        } elseif ($suffix !== 'Core' and class_exists($class.'_Core', false)) {
            // Class extension to be evaluated
            $extension = 'class '.$class.' extends '.$class.'_Core { }';

            // Start class analysis
            $core = new ReflectionClass($class.'_Core');

            if ($core->isAbstract()) {
                // Make the extension abstract
                $extension = 'abstract '.$extension;
            }

            // Transparent class extensions are handled using eval. This is
            // a disgusting hack, but it gets the job done.
            eval($extension);

It is generally not recommended to use eval unless absolutely required.

        }

        return true;
    }

    /**
     * Find a resource file in a given directory. Files will be located according
     * to the order of the include paths. Configuration and i18n files will be
     * returned in reverse order.
     *
     * @throws  Kohana_Exception  if file is required and not found
     * @param   string   directory to search in
     * @param   string   filename to look for (without extension)
     * @param   boolean  file required
     * @param   string   file extension
     * @return  string    if the type is config, i18n or l10n
     * @return  string   if the file is found
     * @return  string    if the file is not found
     */
    public static function find_file($directory, $filename, $required = false, $ext = false)
    {
        // NOTE: This test MUST be not be a strict comparison (===), or empty
        // extensions will be allowed!
        if ($ext == '') {
            // Use the default extension
            $ext = EXT;
        } else {
            // Add a period before the extension
            $ext = '.'.$ext;
        }

        // Search path
        $search = $directory.'/'.$filename.$ext;

        if (isset(self::$internal_cache['find_file_paths'][$search])) {
            return self::$internal_cache['find_file_paths'][$search];
        }

        // Load include paths
        $paths = self::$include_paths;

        // Nothing found, yet
        $found = null;

        if ($directory === 'config' or $directory === 'i18n') {
            // Search in reverse, for merging
            $paths = array_reverse($paths);

            foreach ($paths as $path) {
                if (is_file($path.$search)) {
                    // A matching file has been found
                    $found[] = $path.$search;
                }
            }
        } else {
            foreach ($paths as $path) {
                if (is_file($path.$search)) {
                    // A matching file has been found
                    $found = $path.$search;

                    // Stop searching
                    break;
                }
            }
        }

        if ($found === null) {
            if ($required === true) {
                // Directory i18n key
                $directory = 'core.'.inflector::singular($directory);

                // If the file is required, throw an exception
                throw new Kohana_Exception('core.resource_not_found', self::lang($directory), $filename);
            } else {
                // Nothing was found, return FALSE
                $found = false;
            }
        }

        if (! isset(self::$write_cache['find_file_paths'])) {
            // Write cache at shutdown
            self::$write_cache['find_file_paths'] = true;
        }

        return self::$internal_cache['find_file_paths'][$search] = $found;

The expression self::$internal_cache['find_file_paths'][$search] = $found; of type false|string adds false to the return on line 1052 which is incompatible with the return type documented by Kohana::find_file of type string. It seems like you forgot to handle an error condition.

    }

    /**
     * Lists all files and directories in a resource path.
     *
     * @param   string   directory to search
     * @param   boolean  list all files to the maximum depth?
     * @param   string   full path to search (used for recursion, *never* set this manually)
     * @return  array    filenames and directories
     */
    public static function list_files($directory, $recursive = false, $path = false)
    {
        $files = array();

        if ($path === false) {
            $paths = array_reverse(self::include_paths());

            foreach ($paths as $path) {
                // Recursively get and merge all files
                $files = array_merge($files, self::list_files($directory, $recursive, $path.$directory));

$path . $directory is of type string, but the function expects a boolean.

            }
        } else {
            $path = rtrim($path, '/').'/';

            if (is_readable($path)) {
                $items = (array) glob($path.'*');

                if (! empty($items)) {
                    foreach ($items as $index => $item) {
                        $files[] = $item = str_replace('\\', '/', $item);

                        // Handle recursion
                        if (is_dir($item) and $recursive == true) {

It seems like you are loosely comparing two booleans. Considering using the strict comparison === instead.

                            // Filename should only be the basename
                            $item = pathinfo($item, PATHINFO_BASENAME);

                            // Append sub-directory search
                            $files = array_merge($files, self::list_files($directory, true, $path.$item));

$path . $item is of type string, but the function expects a boolean.

                        }
                    }
                }
            }
        }

        return $files;
    }

    /**
     * Fetch an i18n language item.
     *
     * @param   string  language key to fetch
     * @param   array   additional information to insert into the line
     * @return  string  i18n language string, or the requested key if the i18n item is not found
     */
    public static function lang($key, $args = array())
    {
        // Extract the main group from the key
        $group = explode('.', $key, 2);
        $group = $group[0];

        // Get locale name
        $locale = self::config('locale.language.0');

        if (! isset(self::$internal_cache['language'][$locale][$group])) {
            // Messages for this group
            $messages = array();

            if ($files = self::find_file('i18n', $locale.'/'.$group)) {
                foreach ($files as $file) {

The expression $files of type string is not traversable.

                    include $file;

                    // Merge in configuration
                    if (! empty($lang) and is_array($lang)) {
                        foreach ($lang as $k => $v) {
                            $messages[$k] = $v;
                        }
                    }
                }
            }

            if (! isset(self::$write_cache['language'])) {
                // Write language cache
                self::$write_cache['language'] = true;
            }

            self::$internal_cache['language'][$locale][$group] = $messages;
        }

        // Get the line from cache
        $line = self::key_string(self::$internal_cache['language'][$locale], $key);

        if ($line === null) {
            self::log('error', 'Missing i18n entry '.$key.' for language '.$locale);

            // Return the key string as fallback
            return $key;
        }

        if (is_string($line) and func_num_args() > 1) {
            $args = array_slice(func_get_args(), 1);

            // Add the arguments into the line
            $line = vsprintf($line, is_array($args[0]) ? $args[0] : $args);
        }

        return $line;
    }

    /**
     * Returns the value of a key, defined by a 'dot-noted' string, from an array.
     *
     * @param   array   array to search
     * @param   string  dot-noted string: foo.bar.baz
     * @return  string  if the key is found
     * @return  void    if the key is not found
     */
    public static function key_string($array, $keys)
    {
        if (empty($array)) {
            return null;
        }

        // Prepare for loop
        $keys = explode('.', $keys);

        do {
            // Get the next key
            $key = array_shift($keys);

            if (isset($array[$key])) {
                if (is_array($array[$key]) and ! empty($keys)) {
                    // Dig down to prepare the next loop
                    $array = $array[$key];
                } else {
                    // Requested key was found
                    return $array[$key];
                }
            } else {
                // Requested key is not set
                break;
            }
        } while (! empty($keys));

        return null;
    }

    /**
     * Sets values in an array by using a 'dot-noted' string.
     *
     * @param   array   array to set keys in (reference)
     * @param   string  dot-noted string: foo.bar.baz
     * @return  mixed   fill value for the key
     * @return  void

Consider making the return type a bit more specific; maybe use array|null.

     */
    public static function key_string_set(& $array, $keys, $fill = null)
    {
        if (is_object($array) and ($array instanceof ArrayObject)) {
            // Copy the array
            $array_copy = $array->getArrayCopy();

            // Is an object
            $array_object = true;
        } else {
            if (! is_array($array)) {
                // Must always be an array
                $array = (array) $array;
            }

            // Copy is a reference to the array
            $array_copy =& $array;
        }

        if (empty($keys)) {
            return $array;
        }

        // Create keys
        $keys = explode('.', $keys);

        // Create reference to the array
        $row =& $array_copy;

        for ($i = 0, $end = count($keys) - 1; $i <= $end; $i++) {
            // Get the current key
            $key = $keys[$i];

            if (! isset($row[$key])) {
                if (isset($keys[$i + 1])) {
                    // Make the value an array
                    $row[$key] = array();
                } else {
                    // Add the fill key
                    $row[$key] = $fill;
                }
            } elseif (isset($keys[$i + 1])) {
                // Make the value an array
                $row[$key] = (array) $row[$key];
            }

            // Go down a level, creating a new row reference
            $row =& $row[$key];
        }

        if (isset($array_object)) {
            // Swap the array back in
            $array->exchangeArray($array_copy);

The method exchangeArray cannot be called on $array (of type array).

        }
    }

    /**
     * Retrieves current user agent information:
     * keys:  browser, version, platform, mobile, robot, referrer, languages, charsets
     * tests: is_browser, is_mobile, is_robot, accept_lang, accept_charset
     *
     * @param   string   key or test name
     * @param   string   used with "accept" tests: user_agent(accept_lang, en)
     * @return  array    languages and charsets
     * @return  string   all other keys
     * @return  boolean  all tests
     */
    public static function user_agent($key = 'agent', $compare = null)

user_agent uses the super-global variable $_SERVER which is generally not recommended.

    {
        static $info;

        // Return the raw string
        if ($key === 'agent') {
            return self::$user_agent;

The return type of return self::$user_agent; (string) is incompatible with the return type documented by Kohana::user_agent of type array.

        }

        if ($info === null) {
            // Parse the user agent and extract basic information
            $agents = self::config('user_agents');

            foreach ($agents as $type => $data) {

The expression $agents of type string is not traversable.

                foreach ($data as $agent => $name) {
                    if (stripos(self::$user_agent, $agent) !== false) {
                        if ($type === 'browser' and preg_match('|'.preg_quote($agent).'[^0-9.]*+([0-9.][0-9.a-z]*)|i', self::$user_agent, $match)) {
                            // Set the browser version
                            $info['version'] = $match[1];
                        }

                        // Set the agent name
                        $info[$type] = $name;
                        break;
                    }
                }
            }
        }

        if (empty($info[$key])) {
            switch ($key) {
                case 'is_robot':
                case 'is_browser':
                case 'is_mobile':
                    // A boolean result
                    $return = ! empty($info[substr($key, 3)]);
                break;
                case 'languages':

This code seems to be duplicated across your project.

                    $return = array();
                    if (! empty($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
                        if (preg_match_all('/[-a-z]{2,}/', strtolower(trim($_SERVER['HTTP_ACCEPT_LANGUAGE'])), $matches)) {
                            // Found a result
                            $return = $matches[0];
                        }
                    }
                break;
                case 'charsets':

This code seems to be duplicated across your project.

                    $return = array();
                    if (! empty($_SERVER['HTTP_ACCEPT_CHARSET'])) {
                        if (preg_match_all('/[-a-z0-9]{2,}/', strtolower(trim($_SERVER['HTTP_ACCEPT_CHARSET'])), $matches)) {
                            // Found a result
                            $return = $matches[0];
                        }
                    }
                break;
                case 'referrer':
                    if (! empty($_SERVER['HTTP_REFERER'])) {
                        // Found a result
                        $return = trim($_SERVER['HTTP_REFERER']);
                    }
                break;
            }

            // Cache the return value
            isset($return) and $info[$key] = $return;
        }

        if (! empty($compare)) {
            // The comparison must always be lowercase
            $compare = strtolower($compare);

            switch ($key) {
                case 'accept_lang':
                    // Check if the lange is accepted
                    return in_array($compare, self::user_agent('languages'));

The return type of return in_array($compare, self::user_agent('languages')); (boolean) is incompatible with the return type documented by Kohana::user_agent of type array.

                break;

break is not strictly necessary here and could be removed.

                case 'accept_charset':
                    // Check if the charset is accepted
                    return in_array($compare, self::user_agent('charsets'));

The return type of return in_array($compare, self::user_agent('charsets')); (boolean) is incompatible with the return type documented by Kohana::user_agent of type array.

                break;

break is not strictly necessary here and could be removed.

                default:
                    // Invalid comparison
                    return false;

The return type of return false; (false) is incompatible with the return type documented by Kohana::user_agent of type array.

                break;

break is not strictly necessary here and could be removed.

            }
        }

        // Return the key, if set
        return isset($info[$key]) ? $info[$key] : null;
    }

    /**
     * Quick debugging of any variable. Any number of parameters can be set.
     *
     * @return  string

Should the return type not be null|string?

     */
    public static function debug()
    {
        if (func_num_args() === 0) {
            return;
        }

        // Get params
        $params = func_get_args();
        $output = array();

        foreach ($params as $var) {
            $output[] = '<pre>('.gettype($var).') '.html::specialchars(print_r($var, true)).'</pre>';
        }

        return implode("\n", $output);
    }

    /**
     * Displays nice backtrace information.
     * @see http://php.net/debug_backtrace
     *
     * @param   array   backtrace generated by an exception or debug_backtrace
     * @return  string

Should the return type not be null|string?

     */
    public static function backtrace($trace)
    {
        if (! is_array($trace)) {
            return;
        }

        // Final output
        $output = array();

        foreach ($trace as $entry) {
            $temp = '<li>';

            if (isset($entry['file'])) {
                $temp .= self::lang('core.error_file_line', preg_replace('!^'.preg_quote(DOCROOT).'!', '', $entry['file']), $entry['line']);
            }

            $temp .= '<pre>';

            if (isset($entry['class'])) {
                // Add class and call type
                $temp .= $entry['class'].$entry['type'];
            }

            // Add function
            $temp .= $entry['function'].'( ';

            // Add function args
            if (isset($entry['args']) and is_array($entry['args'])) {
                // Separator starts as nothing
                $sep = '';

                while ($arg = array_shift($entry['args'])) {
                    if (is_string($arg) and is_file($arg)) {
                        // Remove docroot from filename
                        $arg = preg_replace('!^'.preg_quote(DOCROOT).'!', '', $arg);
                    }

                    $temp .= $sep.html::specialchars(print_r($arg, true));

                    // Change separator to a comma
                    $sep = ', ';
                }
            }

            $temp .= ' )</pre></li>';

            $output[] = $temp;
        }

        return '<ul class="backtrace">'.implode("\n", $output).'</ul>';
    }

    /**
     * Saves the internal caches: configuration, include paths, etc.
     *
     * @return  boolean
     */
    public static function internal_cache_save()
    {
        if (! is_array(self::$write_cache)) {
            return false;
        }

        // Get internal cache names
        $caches = array_keys(self::$write_cache);

        // Nothing written
        $written = false;

        foreach ($caches as $cache) {
            if (isset(self::$internal_cache[$cache])) {
                // Write the cache file
                self::cache_save($cache, self::$internal_cache[$cache], self::$configuration['core']['internal_cache']);

                // A cache has been written
                $written = true;
            }
        }

        return $written;
    }
} // End Kohana

/**
 * Creates a generic i18n exception.
 */
class Kohana_Exception extends Exception
{

    // Template file
    protected $template = 'kohana_error_page';

    // Header
    protected $header = false;

    // Error code
    protected $code = E_KOHANA;

    /**
     * Set exception message.
     *
     * @param  string  i18n language key for the message
     * @param  array   addition line parameters
     * @param string $error
     */
    public function __construct($error)
    {
        $args = array_slice(func_get_args(), 1);

        // Fetch the error message
        $message = Kohana::lang($error, $args);

        if ($message === $error or empty($message)) {
            // Unable to locate the message for the error
            $message = 'Unknown Exception: '.$error;
        }

        // Sets $this->message the proper way
        parent::__construct($message);
    }

    /**
     * Magic method for converting an object to a string.
     *
     * @return  string  i18n message
     */
    public function __toString()
    {
        return (string) $this->message;
    }

    /**
     * Fetch the template name.
     *
     * @return  string
     */
    public function getTemplate()
    {
        return $this->template;
    }

    /**
     * Sends an Internal Server Error header.
     *
     * @return  void
     */
    public function sendHeaders()
    {
        // Send the 500 header
        header('HTTP/1.1 500 Internal Server Error');
    }
} // End Kohana Exception

/**
 * Creates a custom exception.
 */
class Kohana_User_Exception extends Kohana_Exception
{

    /**
     * Set exception title and message.
     *
     * @param   string  exception title string
     * @param   string  exception message string
     * @param   string  custom error template
     * @param string $title
     * @param null|string $message
     */
    public function __construct($title, $message, $template = false)
    {
        Exception::__construct($message);

        $this->code = $title;

        if ($template !== false) {
            $this->template = $template;

The property $template was declared of type string, but $template is of type boolean. Maybe add a type cast?

        }
    }
} // End Kohana PHP Exception

/**
 * Creates a Page Not Found exception.
 */
class Kohana_404_Exception extends Kohana_Exception
{
    protected $code = E_PAGE_NOT_FOUND;

    /**
     * Set internal properties.
     *
     * @param  string  URL of page
     * @param  string  custom error template
     */
    public function __construct($page = false, $template = false)
    {
        if ($page === false) {
            // Construct the page URI using Router properties
            $page = Router::$current_uri.Router::$url_suffix.Router::$query_string;
        }

        Exception::__construct(Kohana::lang('core.page_not_found', $page));

        $this->template = $template;

The property $template was declared of type string, but $template is of type boolean. Maybe add a type cast?

    }

    /**
     * Sends "File Not Found" headers, to emulate server behavior.
     *
     * @return void
     */
    public function sendHeaders()
    {
        // Send the 404 header
        header('HTTP/1.1 404 File Not Found');
    }
} // End Kohana 404 Exception