includes/wikiengine/Parse.php
author Dan
Fri, 05 Oct 2007 01:57:00 -0400
changeset 161 e1a22031b5bd
parent 1 fe660c52c48f
permissions -rw-r--r--
Major revamps to the template parser. Fixed a few security holes that could allow PHP to be injected in untimely places in TPL code. Improved Ux for XSS attempt in tplWikiFormat. Documented many functions. Backported much cleaner parser from 2.0 branch. Beautified a lot of code in the depths of the template class. Pretty much a small-scale Extreme Makeover.

<?php
// vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4:
/**
 * Baseline rule class for extension into a "real" parser component.
 *
 * PHP versions 4 and 5
 *
 * @category   Text
 * @package    Text_Wiki
 * @author     Paul M. Jones <pmjones@php.net>
 * @license    http://www.gnu.org/copyleft/lesser.html  LGPL License 2.1
 * @version    CVS: $Id: Parse.php,v 1.5 2005/07/29 08:57:29 toggg Exp $
 * @link       http://pear.php.net/package/Text_Wiki
 */

/**
 * Baseline rule class for extension into a "real" parser component.
 *
 * Text_Wiki_Rule classes do not stand on their own; they are called by a
 * Text_Wiki object, typcially in the transform() method. Each rule class
 * performs three main activities: parse, process, and render.
 *
 * The parse() method takes a regex and applies it to the whole block of
 * source text at one time. Each match is sent as $matches to the
 * process() method.
 *
 * The process() method acts on the matched text from the source, and
 * then processes the source text is some way.  This may mean the
 * creation of a delimited token using addToken().  In every case, the
 * process() method returns the text that should replace the matched text
 * from parse().
 *
 * @category   Text
 * @package    Text_Wiki
 * @author     Paul M. Jones <pmjones@php.net>
 * @license    http://www.gnu.org/copyleft/lesser.html  LGPL License 2.1
 * @version    Release: @package_version@
 * @link       http://pear.php.net/package/Text_Wiki
 */
class Text_Wiki_Parse {


    /**
    *
    * Configuration options for this parser rule.
    *
    * @access public
    *
    * @var string
    *
    */

    var $conf = array();


    /**
    *
    * Regular expression to find matching text for this rule.
    *
    * @access public
    *
    * @var string
    *
    * @see parse()
    *
    */

    var $regex = null;


    /**
    *
    * The name of this rule for new token array elements.
    *
    * @access public
    *
    * @var string
    *
    */

    var $rule = null;


    /**
    *
    * A reference to the calling Text_Wiki object.
    *
    * This is needed so that each rule has access to the same source
    * text, token set, URLs, interwiki maps, page names, etc.
    *
    * @access public
    *
    * @var object
    */

    var $wiki = null;


    /**
    *
    * Constructor for this parser rule.
    *
    * @access public
    *
    * @param object &$obj The calling "parent" Text_Wiki object.
    *
    */

    function Text_Wiki_Parse(&$obj)
    {
        // set the reference to the calling Text_Wiki object;
        // this allows us access to the shared source text, token
        // array, etc.
        $this->wiki =& $obj;

        // set the name of this rule; generally used when adding
        // to the tokens array. strip off the Text_Wiki_Parse_ portion.
        // text_wiki_parse_
        // 0123456789012345
        $tmp = substr(get_class($this), 16);
        $this->rule = ucwords(strtolower($tmp));

        // override config options for the rule if specified
        if (isset($this->wiki->parseConf[$this->rule]) &&
            is_array($this->wiki->parseConf[$this->rule])) {

            $this->conf = array_merge(
                $this->conf,
                $this->wiki->parseConf[$this->rule]
            );

        }
    }


    /**
    *
    * Abstrct method to parse source text for matches.
    *
    * Applies the rule's regular expression to the source text, passes
    * every match to the process() method, and replaces the matched text
    * with the results of the processing.
    *
    * @access public
    *
    * @see Text_Wiki_Parse::process()
    *
    */

    function parse()
    {
        $this->wiki->source = preg_replace_callback(
            $this->regex,
            array(&$this, 'process'),
            $this->wiki->source
        );
    }


    /**
    *
    * Abstract method to generate replacements for matched text.
    *
    * @access public
    *
    * @param array $matches An array of matches from the parse() method
    * as generated by preg_replace_callback.  $matches[0] is the full
    * matched string, $matches[1] is the first matched pattern,
    * $matches[2] is the second matched pattern, and so on.
    *
    * @return string The processed text replacement; defaults to the
    * full matched string (i.e., no changes to the text).
    *
    * @see Text_Wiki_Parse::parse()
    *
    */

    function process(&$matches)
    {
        return $matches[0];
    }


    /**
    *
    * Simple method to safely get configuration key values.
    *
    * @access public
    *
    * @param string $key The configuration key.
    *
    * @param mixed $default If the key does not exist, return this value
    * instead.
    *
    * @return mixed The configuration key value (if it exists) or the
    * default value (if not).
    *
    */

    function getConf($key, $default = null)
    {
        if (isset($this->conf[$key])) {
            return $this->conf[$key];
        } else {
            return $default;
        }
    }


    /**
    *
    * Extract 'attribute="value"' portions of wiki markup.
    *
    * This kind of markup is typically used only in macros, but is useful
    * anywhere.
    *
    * The syntax is pretty strict; there can be no spaces between the
    * option name, the equals, and the first double-quote; the value
    * must be surrounded by double-quotes.  You can escape characters in
    * the value with a backslash, and the backslash will be stripped for
    * you.
    *
    * @access public
    *
    * @param string $text The "attributes" portion of markup.
    *
    * @return array An associative array of key-value pairs where the
    * key is the option name and the value is the option value.
    *
    */

    function getAttrs($text)
    {
        // find the =" sections;
        $tmp = explode('="', trim($text));

        // basic setup
        $k = count($tmp) - 1;
        $attrs = array();
        $key = null;

        // loop through the sections
        foreach ($tmp as $i => $val) {

            // first element is always the first key
            if ($i == 0) {
                $key = trim($val);
                continue;
            }

            // find the last double-quote in the value.
            // the part to the left is the value for the last key,
            // the part to the right is the next key name
            $pos = strrpos($val, '"');
            $attrs[$key] = stripslashes(substr($val, 0, $pos));
            $key = trim(substr($val, $pos+1));

        }

        return $attrs;

    }
}
?>