ci 执行流程

index.php 文件

加载codeigniter文件

codeigniter部分里面加载的：

• 加载配置文件constants

• 加载全局公共函数core/Common.php 文件

• 全局变量获取变量

• 判断是否composer加载程序(个人感觉 还是单个加载的方便)

  使用刚才加载的common里面的函数load_class

  • 加载 Benchmark基准测试类(这个类主要用来记录程序的执行时间、内存使用、cpu使用等情况)
  • 加载 钩子类 扩展用 不改变当前的ci核心
  • 加载 配置文件 默认的是你在index.php 里面 设置的config.php 文件,如果找不到则加载apppath的config.php
  • 获取utf8的配置
  • 加载一些函数
  • 加载utf8字集处理
  • 加载解析url
  • 加载路由类 依赖上面的url来判断走向
  • 加载输出类 ci的数据都靠这个了
  • 加载安全类 xss crsf
  • 加载input组件类
  • 加载语言类
  • 加载项目和框架的控制器

     '_ENV', 'G' => '_GET', 'P' => '_POST', 'C' => '_COOKIE', 'S' => '_SERVER') as $key => $superglobal)        {            if (strpos($_registered, $key) === FALSE)            {                continue;            }            foreach (array_keys($$superglobal) as $var)            {                if (isset($GLOBALS[$var]) && ! in_array($var, $_protected, TRUE))                {                    $GLOBALS[$var] = NULL;                }            }        }    }}/* * ------------------------------------------------------ *  Define a custom error handler so we can log PHP errors *  定义自定义错误处理程序，以便记录PHP错误 * ------------------------------------------------------ */    set_error_handler('_error_handler');  //设置用户自定义错误函数    set_exception_handler('_exception_handler'); //设置用户自定义错误异常函数    register_shutdown_function('_shutdown_handler'); // php中止执行的函数/* * ------------------------------------------------------ *  Set the subclass_prefix * 设置子类的前戳 * ------------------------------------------------------ * * Normally the "subclass_prefix" is set in the config file. * The subclass prefix allows CI to know if a core class is * being extended via a library in the local application * "libraries" folder. Since CI allows config items to be * overridden via data set in the main index.php file, * before proceeding we need to know if a subclass_prefix * override exists. If so, we will set this value now, * before any classes are loaded * Note: Since the config file data is cached it doesn't * hurt to load it here. */    if ( ! empty($assign_to_config['subclass_prefix']))    {        get_config(array('subclass_prefix' => $assign_to_config['subclass_prefix']));    }/* * ------------------------------------------------------ *  使用composer加载程序 * ------------------------------------------------------ */    if ($composer_autoload = config_item('composer_autoload'))    {        if ($composer_autoload === TRUE)        {            file_exists(APPPATH.'vendor/autoload.php')                ? require_once(APPPATH.'vendor/autoload.php')                : log_message('error', '$config[\'composer_autoload\'] is set to TRUE but '.APPPATH.'vendor/autoload.php was not found.');        }        elseif (file_exists($composer_autoload))        {            require_once($composer_autoload);        }        else        {            log_message('error', 'Could not find the specified $config[\'composer_autoload\'] path: '.$composer_autoload);        }    }/* * ------------------------------------------------------ *  Start the timer... tick tock tick tock... *  计时器  * ------------------------------------------------------ */    $BM =& load_class('Benchmark', 'core'); // & 引用返回用在当想用函数找到引用应该被绑定在哪一个变量上面时    $BM->mark('total_execution_time_start');    $BM->mark('loading_time:_base_classes_start');/*  * ------------------------------------------------------ *  实例化钩子类 * ------------------------------------------------------ */    $EXT =& load_class('Hooks', 'core');/* * ------------------------------------------------------ *  Is there a "pre_system" hook? *  是否有 pre_system钩子类加载 * ------------------------------------------------------ */    $EXT->call_hook('pre_system'); //pre_system 系统加载早期执行 这个阶段只有 钩子类和基准测试类加载 其他还没加载/* * ------------------------------------------------------ *  实例化配置类 * ------------------------------------------------------ * * Note: It is important that Config is loaded first as * most other classes depend on it either directly or by * depending on another class that uses it. * */    $CFG =& load_class('Config', 'core');             // 在加载的时候index.php文件中是否有手动的配置    if (isset($assign_to_config) && is_array($assign_to_config))    {        foreach ($assign_to_config as $key => $value)        {            $CFG->set_item($key, $value);        }    }/* * ------------------------------------------------------ * 字符集相关的配置 * ------------------------------------------------------ * * Configure mbstring and/or iconv if they are enabled * and set MB_ENABLED and ICONV_ENABLED constants, so * that we don't repeatedly do extension_loaded() or * function_exists() calls. * * Note: UTF-8 class depends on this. It used to be done * in it's constructor, but it's _not_ class-specific. * */    $charset = strtoupper(config_item('charset'));    ini_set('default_charset', $charset);    if (extension_loaded('mbstring'))    {        define('MB_ENABLED', TRUE);        // mbstring.internal_encoding is deprecated starting with PHP 5.6        // and it's usage triggers E_DEPRECATED messages.        @ini_set('mbstring.internal_encoding', $charset);        // This is required for mb_convert_encoding() to strip invalid characters.        // That's utilized by CI_Utf8, but it's also done for consistency with iconv.        mb_substitute_character('none');    }    else    {        define('MB_ENABLED', FALSE);    }    // There's an ICONV_IMPL constant, but the PHP manual says that using    // iconv's predefined constants is "strongly discouraged".    if (extension_loaded('iconv'))    {        define('ICONV_ENABLED', TRUE);        // iconv.internal_encoding is deprecated starting with PHP 5.6        // and it's usage triggers E_DEPRECATED messages.        @ini_set('iconv.internal_encoding', $charset);    }    else    {        define('ICONV_ENABLED', FALSE);    }    if (is_php('5.6'))    {        ini_set('php.internal_encoding', $charset);    }/* * ------------------------------------------------------ *  加载一些定义的东东函数 * ------------------------------------------------------ */    require_once(BASEPATH.'core/compat/mbstring.php');    require_once(BASEPATH.'core/compat/hash.php');    require_once(BASEPATH.'core/compat/password.php');    require_once(BASEPATH.'core/compat/standard.php');/* * ------------------------------------------------------ *  实例化utf8类 * ------------------------------------------------------ */    $UNI =& load_class('Utf8', 'core');/* * ------------------------------------------------------ *  实例化url类 * ------------------------------------------------------ */    $URI =& load_class('URI', 'core');/* * ------------------------------------------------------ *  实例化路由类并设置路由 * ------------------------------------------------------ */    $RTR =& load_class('Router', 'core', isset($routing) ? $routing : NULL);/* * ------------------------------------------------------ *  实例化输出类 * ------------------------------------------------------ */    $OUT =& load_class('Output', 'core');/* * ------------------------------------------------------ *  是否有效的缓存文件 * ------------------------------------------------------ */    if ($EXT->call_hook('cache_override') === FALSE && $OUT->_display_cache($CFG, $URI) === TRUE)    {        exit;    }/* * ----------------------------------------------------- * 加载安全类 * ----------------------------------------------------- */    $SEC =& load_class('Security', 'core');/* * ------------------------------------------------------ *  加载input组件类 * ------------------------------------------------------ */    $IN =& load_class('Input', 'core');/* * ------------------------------------------------------ *  加载语言类 * ------------------------------------------------------ */    $LANG =& load_class('Lang', 'core');/* * ------------------------------------------------------ *  加载项目和框架的控制器 * ------------------------------------------------------ * */    // Load the base controller class    require_once BASEPATH.'core/Controller.php';    /**     * Reference to the CI_Controller method.     *     * Returns current CI instance object     *     * @return CI_Controller     */    function &get_instance()    {        return CI_Controller::get_instance();    }    if (file_exists(APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php'))    {        require_once APPPATH.'core/'.$CFG->config['subclass_prefix'].'Controller.php';    }    if (file_exists(APPPATH.'core/Rest_Controller.php'))    {        require_once APPPATH.'core/Rest_Controller.php';    }    // Set a mark point for benchmarking    $BM->mark('loading_time:_base_classes_end');/* * ------------------------------------------------------ *  Sanity checks * ------------------------------------------------------ * *  The Router class has already validated the request, *  leaving us with 3 options here: * *  1) an empty class name, if we reached the default *     controller, but it didn't exist; *  2) a query string which doesn't go through a *     file_exists() check *  3) a regular request for a non-existing page * *  We handle all of these as a 404 error. * *  Furthermore, none of the methods in the app controller *  or the loader class can be called via the URI, nor can *  controller methods that begin with an underscore. */    $e404 = FALSE;    $class = ucfirst($RTR->class);    $method = $RTR->method;    var_dump(method_exists($class, '_remap'));    exit;    if (empty($class) OR ! file_exists(APPPATH.'controllers/'.$RTR->directory.$class.'.php'))    {        $e404 = TRUE;    }    else    {        require_once(APPPATH.'controllers/'.$RTR->directory.$class.'.php');        if ( ! class_exists($class, FALSE) OR $method[0] === '_' OR method_exists('CI_Controller', $method))        {            $e404 = TRUE;        }        elseif (method_exists($class, '_remap'))        {            $params = array($method, array_slice($URI->rsegments, 2));            $method = '_remap';        }        elseif ( ! method_exists($class, $method))        {            $e404 = TRUE;        }        /**         * DO NOT CHANGE THIS, NOTHING ELSE WORKS!         *         * - method_exists() returns true for non-public methods, which passes the previous elseif         * - is_callable() returns false for PHP 4-style constructors, even if there's a __construct()         * - method_exists($class, '__construct') won't work because CI_Controller::__construct() is inherited         * - People will only complain if this doesn't work, even though it is documented that it shouldn't.         *         * ReflectionMethod::isConstructor() is the ONLY reliable check,         * knowing which method will be executed as a constructor.         */        elseif ( ! is_callable(array($class, $method)))        {            $reflection = new ReflectionMethod($class, $method);            if ( ! $reflection->isPublic() OR $reflection->isConstructor())            {                $e404 = TRUE;            }        }    }    if ($e404)    {        if ( ! empty($RTR->routes['404_override']))        {            if (sscanf($RTR->routes['404_override'], '%[^/]/%s', $error_class, $error_method) !== 2)            {                $error_method = 'index';            }            $error_class = ucfirst($error_class);            if ( ! class_exists($error_class, FALSE))            {                if (file_exists(APPPATH.'controllers/'.$RTR->directory.$error_class.'.php'))                {                    require_once(APPPATH.'controllers/'.$RTR->directory.$error_class.'.php');                    $e404 = ! class_exists($error_class, FALSE);                }                // Were we in a directory? If so, check for a global override                elseif ( ! empty($RTR->directory) && file_exists(APPPATH.'controllers/'.$error_class.'.php'))                {                    require_once(APPPATH.'controllers/'.$error_class.'.php');                    if (($e404 = ! class_exists($error_class, FALSE)) === FALSE)                    {                        $RTR->directory = '';                    }                }            }            else            {                $e404 = FALSE;            }        }        // Did we reset the $e404 flag? If so, set the rsegments, starting from index 1        if ( ! $e404)        {            $class = $error_class;            $method = $error_method;            $URI->rsegments = array(                1 => $class,                2 => $method            );        }        else        {            show_404($RTR->directory.$class.'/'.$method);        }    }    if ($method !== '_remap')    {        $params = array_slice($URI->rsegments, 2);    }/* * ------------------------------------------------------ *  Is there a "pre_controller" hook? * ------------------------------------------------------ */    $EXT->call_hook('pre_controller');/* * ------------------------------------------------------ *  Instantiate the requested controller * ------------------------------------------------------ */    // Mark a start point so we can benchmark the controller    $BM->mark('controller_execution_time_( '.$class.' / '.$method.' )_start');    $CI = new $class();/* * ------------------------------------------------------ *  Is there a "post_controller_constructor" hook? * ------------------------------------------------------ */    $EXT->call_hook('post_controller_constructor');/* * ------------------------------------------------------ *  Call the requested method * ------------------------------------------------------ */    call_user_func_array(array(&$CI, $method), $params);    // Mark a benchmark end point    $BM->mark('controller_execution_time_( '.$class.' / '.$method.' )_end');/* * ------------------------------------------------------ *  Is there a "post_controller" hook? * ------------------------------------------------------ */    $EXT->call_hook('post_controller');/* * ------------------------------------------------------ *  Send the final rendered output to the browser * ------------------------------------------------------ */    if ($EXT->call_hook('display_override') === FALSE)    {        $OUT->_display();    }/* * ------------------------------------------------------ *  Is there a "post_system" hook? * ------------------------------------------------------ */    $EXT->call_hook('post_system');