php mvc框架

<?php
$endrun=false;
define("CONTROLLERS_DIR",dirname(__FILE__).'/controllers/');
define("VIEWS_DIR",dirname(__FILE__).'/views/');
define("MODELS_DIR",dirname(__FILE__).'/models/');
define("CONFIG_DIR",dirname(__FILE__).'/config/');
define("CLASSS_DIR",dirname(__FILE__).'/classs/');
define("CONFIG_FILE",'config.php');
if(file_exists(CONFIG_DIR.CONFIG_FILE))
{
    require(CONFIG_DIR.CONFIG_FILE);
}
function inti()
{
    set_error_handler('error_handler');
    register_shutdown_function('shutdown_func');
    if(version_compare(PHP_VERSION,'5.4.0','<')) 
    {
        ini_set('magic_quotes_runtime',0);
    }
    else
    {
        define('MAGIC_QUOTES_GPC',false);
    }
    if(get_config('charset')!='error')
    {
        ini_set('default_charset',get_config('charset'));
    }
    if(get_config('appname')!='error')
    {
        header('X-Powered-By:'.get_config('appname'));
    }
    if(get_config('timezone')!='error')
    {
        ini_set('date.timezone',get_config('timezone'));
    }
    if(get_config('debug')!='error')
    {
        if(get_config('debug')==false)
        {
            ini_set("display_errors", "off");
        }
        if(get_config('debug')==true)
        {
            ini_set("display_errors", "on");
        }
    }
}
function get_query()
{
    $request_url=$_SERVER['REQUEST_URI'];
    $a=explode('/',$request_url);
    $length=count($a);
    if($length<4)
    {
        return false;
    }
    else
    {
        $s=$a[3];
        if(strpos($s,'.html')===false)
        {
            return $s;
        }
        else
        {
            return str_replace('.html','',$s);
        }
    }

}
function get_config($key)
{
    if(isset($GLOBALS['config']))
    {
        if(is_array($GLOBALS['config']))
        {
            if(array_key_exists($key,$GLOBALS['config']))
            {
                return $GLOBALS['config'][$key];
            }
        }
    }
    return 'error';
}
function is_method($method)
{
    $m=$_SERVER['REQUEST_METHOD'];
    if(strtoupper($method)==$m)
    {
        return true;
    }
    return false;
}
//页面跳转
function redirect($url)
{
    header('Location:'.$url);
    exit();
}
//载入model
function model($name)
{
    $name.='_model';
    if(file_exists(MODELS_DIR.$name.'.php'))
    {
        require_once(MODELS_DIR.$name.'.php');
        if(class_exists($name))
        {
            $c=new $name;
            return $c;
        }
    }
    return false;
}
//载入class
function load_class($name)
{
    if(file_exists(CLASSS_DIR.$name.'.php'))
    {
        include(CLASSS_DIR.$name.'.php');
    }
}
function error_handler($errno,$errstr,$errfile,$errline)
{
    if (!(error_reporting() & $errno)) 
    {
       return;
    }
    echo 'something is wrong!';
}
function shutdown_func()
{
    if(!$GLOBALS['endrun'])
    {
        echo("500 something is wrong!");
    }
}
function map()
{
    $request_url=$_SERVER['REQUEST_URI'];
    if($request_url=='/')
    {
        instance('index','index');
    }
    else
    {
        $a=explode('/',$request_url);
        $length=count($a);
        $c=$a[1];
        if($length>=3)
        {
            $m=$a[2];
            if($m=="")
            {
                instance($c,$c);
            }
            else
            {
                instance($c,$m);
            }
        }
        else
        {
            instance($c,$c);
        }
    }
    $GLOBALS['endrun']=true;
}
function instance($c,$m)
{
    $c.='_controller';
    $m.='_action';
    if(file_exists(CONTROLLERS_DIR.$c.'.php'))
    {
        require_once(CONTROLLERS_DIR.$c.'.php');
        if(class_exists($c))
        {
            if(method_exists($c,$m))
            {
                $r=new $c;
                if($c!=$m)
                {
                    $r->$m();
                }
            }
            else
            {
                echo '404 not found';
            }
        }
        else
        {
            echo '404 not found';
        }
    }
    else
    {
        echo '404 not found';
    }
}
function json($arr)
{
    header('content-type:application/json; charset=utf-8');
    if(is_array($arr))
    {
        echo json_encode($arr);
        return;
    }
    echo json_decode(array('error'=>'parameter error'));
}
function text($str)
{
    header('content-type:text/plain; charset=utf-8');
    echo $str;
}
function render($view,$data = null)
{
    $path=VIEWS_DIR.$view.'.php';
    if(file_exists($path))
    {
        header('content-type:text/html; charset=utf-8');
        ob_start();
        if(is_array($data))
        {
            extract($data);
        }
        require $path;
        echo trim(ob_get_clean());
    }
    else
    {
        echo 'template not found';
    }
}
function run()
{
    inti();
    map();
}
run();
?>