/common/libraries/plugin/htmlpurifier/library/HTMLPurifier/URIFilter/MakeAbsolute.php

<?php



// does not support network paths





class HTMLPurifier_URIFilter_MakeAbsolute extends HTMLPurifier_URIFilter

{

    public $name = 'MakeAbsolute';

    protected $base;

    protected $basePathStack = array();



    public function prepare($config)

    {

        $def = $config->getDefinition('URI');

        $this->base = $def->base;

        if (is_null($this->base))

        {

            trigger_error('URI.MakeAbsolute is being ignored due to lack of value for URI.Base configuration', E_USER_WARNING);

            return false;

        }

        $this->base->fragment = null; // fragment is invalid for base URI

        $stack = explode('/', $this->base->path);

        array_pop($stack); // discard last segment

        $stack = $this->_collapseStack($stack); // do pre-parsing

        $this->basePathStack = $stack;

        return true;

    }



    public function filter(&$uri, $config, $context)

    {

        if (is_null($this->base))

            return true; // abort early

        if ($uri->path === '' && is_null($uri->scheme) && is_null($uri->host) && is_null($uri->query) && is_null($uri->fragment))

        {

            // reference to current document

            $uri = clone $this->base;

            return true;

        }

        if (! is_null($uri->scheme))

        {

            // absolute URI already: don't change

            if (! is_null($uri->host))

                return true;

            $scheme_obj = $uri->getSchemeObj($config, $context);

            if (! $scheme_obj)

            {

                // scheme not recognized

                return false;

            }

            if (! $scheme_obj->hierarchical)

            {

                // non-hierarchal URI with explicit scheme, don't change

                return true;

            }

        

     // special case: had a scheme but always is hierarchical and had no authority

        }

        if (! is_null($uri->host))

        {

            // network path, don't bother

            return true;

        }

        if ($uri->path === '')

        {

            $uri->path = $this->base->path;

        }

        elseif ($uri->path[0] !== '/')

        {

            // relative path, needs more complicated processing

            $stack = explode('/', $uri->path);

            $new_stack = array_merge($this->basePathStack, $stack);

            if ($new_stack[0] !== '' && ! is_null($this->base->host))

            {

                array_unshift($new_stack, '');

            }

            $new_stack = $this->_collapseStack($new_stack);

            $uri->path = implode('/', $new_stack);

        }

        else

        {

            // absolute path, but still we should collapse

            $uri->path = implode('/', $this->_collapseStack(explode('/', $uri->path)));

        }

        // re-combine

        $uri->scheme = $this->base->scheme;

        if (is_null($uri->userinfo))

            $uri->userinfo = $this->base->userinfo;

        if (is_null($uri->host))

            $uri->host = $this->base->host;

        if (is_null($uri->port))

            $uri->port = $this->base->port;

        return true;

    }



    /**

     * Resolve dots and double-dots in a path stack

     */

    private function _collapseStack($stack)

    {

        $result = array();

        $is_folder = false;

        for($i = 0; isset($stack[$i]); $i ++)

        {

            $is_folder = false;

            // absorb an internally duplicated slash

            if ($stack[$i] == '' && $i && isset($stack[$i + 1]))

                continue;

            if ($stack[$i] == '..')

            {

                if (! empty($result))

                {

                    $segment = array_pop($result);

                    if ($segment === '' && empty($result))

                    {

                        // error case: attempted to back out too far:

                        // restore the leading slash

                        $result[] = '';

                    }

                    elseif ($segment === '..')

                    {

                        $result[] = '..'; // cannot remove .. with ..

                    }

                }

                else

                {

                    // relative path, preserve the double-dots

                    $result[] = '..';

                }

                $is_folder = true;

                continue;

            }

            if ($stack[$i] == '.')

            {

                // silently absorb

                $is_folder = true;

                continue;

            }

            $result[] = $stack[$i];

        }

        if ($is_folder)

            $result[] = '';

        return $result;

    }

}



// vim: et sw=4 sts=4