installed dokuwiki, added to navbar, updated news

1 files changed, 790 insertions, 0 deletions

diff --git a/wiki/inc/parserutils.php b/wiki/inc/parserutils.php
new file mode 100644
index 0000000..5b0cab0
--- /dev/null
+++ b/wiki/inc/parserutils.php
@@ -0,0 +1,790 @@
+<?php
+/**
+ * Utilities for accessing the parser
+ *
+ * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
+ * @author     Harry Fuecks <hfuecks@gmail.com>
+ * @author     Andreas Gohr <andi@splitbrain.org>
+ */
+
+if(!defined('DOKU_INC')) die('meh.');
+
+/**
+ * How many pages shall be rendered for getting metadata during one request
+ * at maximum? Note that this limit isn't respected when METADATA_RENDER_UNLIMITED
+ * is passed as render parameter to p_get_metadata.
+ */
+if (!defined('P_GET_METADATA_RENDER_LIMIT')) define('P_GET_METADATA_RENDER_LIMIT', 5);
+
+/** Don't render metadata even if it is outdated or doesn't exist */
+define('METADATA_DONT_RENDER', 0);
+/**
+ * Render metadata when the page is really newer or the metadata doesn't exist.
+ * Uses just a simple check, but should work pretty well for loading simple
+ * metadata values like the page title and avoids rendering a lot of pages in
+ * one request. The P_GET_METADATA_RENDER_LIMIT is used in this mode.
+ * Use this if it is unlikely that the metadata value you are requesting
+ * does depend e.g. on pages that are included in the current page using
+ * the include plugin (this is very likely the case for the page title, but
+ * not for relation references).
+ */
+define('METADATA_RENDER_USING_SIMPLE_CACHE', 1);
+/**
+ * Render metadata using the metadata cache logic. The P_GET_METADATA_RENDER_LIMIT
+ * is used in this mode. Use this mode when you are requesting more complex
+ * metadata. Although this will cause rendering more often it might actually have
+ * the effect that less current metadata is returned as it is more likely than in
+ * the simple cache mode that metadata needs to be rendered for all pages at once
+ * which means that when the metadata for the page is requested that actually needs
+ * to be updated the limit might have been reached already.
+ */
+define('METADATA_RENDER_USING_CACHE', 2);
+/**
+ * Render metadata without limiting the number of pages for which metadata is
+ * rendered. Use this mode with care, normally it should only be used in places
+ * like the indexer or in cli scripts where the execution time normally isn't
+ * limited. This can be combined with the simple cache using
+ * METADATA_RENDER_USING_CACHE | METADATA_RENDER_UNLIMITED.
+ */
+define('METADATA_RENDER_UNLIMITED', 4);
+
+/**
+ * Returns the parsed Wikitext in XHTML for the given id and revision.
+ *
+ * If $excuse is true an explanation is returned if the file
+ * wasn't found
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param string $id page id
+ * @param string|int $rev revision timestamp or empty string
+ * @param bool $excuse
+ * @param string $date_at
+ *
+ * @return null|string
+ */
+function p_wiki_xhtml($id, $rev='', $excuse=true,$date_at=''){
+    $file = wikiFN($id,$rev);
+    $ret  = '';
+
+    //ensure $id is in global $ID (needed for parsing)
+    global $ID;
+    $keep = $ID;
+    $ID   = $id;
+
+    if($rev || $date_at){
+        if(file_exists($file)){
+            $ret = p_render('xhtml',p_get_instructions(io_readWikiPage($file,$id,$rev)),$info,$date_at); //no caching on old revisions
+        }elseif($excuse){
+            $ret = p_locale_xhtml('norev');
+        }
+    }else{
+        if(file_exists($file)){
+            $ret = p_cached_output($file,'xhtml',$id);
+        }elseif($excuse){
+            $ret = p_locale_xhtml('newpage');
+        }
+    }
+
+    //restore ID (just in case)
+    $ID = $keep;
+
+    return $ret;
+}
+
+/**
+ * Returns the specified local text in parsed format
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param string $id page id
+ * @return null|string
+ */
+function p_locale_xhtml($id){
+    //fetch parsed locale
+    $html = p_cached_output(localeFN($id));
+    return $html;
+}
+
+/**
+ * Returns the given file parsed into the requested output format
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ * @author Chris Smith <chris@jalakai.co.uk>
+ *
+ * @param string $file filename, path to file
+ * @param string $format
+ * @param string $id page id
+ * @return null|string
+ */
+function p_cached_output($file, $format='xhtml', $id='') {
+    global $conf;
+
+    $cache = new cache_renderer($id, $file, $format);
+    if ($cache->useCache()) {
+        $parsed = $cache->retrieveCache(false);
+        if($conf['allowdebug'] && $format=='xhtml') {
+            $parsed .= "\n<!-- cachefile {$cache->cache} used -->\n";
+        }
+    } else {
+        $parsed = p_render($format, p_cached_instructions($file,false,$id), $info);
+
+        if ($info['cache'] && $cache->storeCache($parsed)) {              // storeCache() attempts to save cachefile
+            if($conf['allowdebug'] && $format=='xhtml') {
+                $parsed .= "\n<!-- no cachefile used, but created {$cache->cache} -->\n";
+            }
+        }else{
+            $cache->removeCache();                     //try to delete cachefile
+            if($conf['allowdebug'] && $format=='xhtml') {
+                $parsed .= "\n<!-- no cachefile used, caching forbidden -->\n";
+            }
+        }
+    }
+
+    return $parsed;
+}
+
+/**
+ * Returns the render instructions for a file
+ *
+ * Uses and creates a serialized cache file
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param string $file      filename, path to file
+ * @param bool   $cacheonly
+ * @param string $id        page id
+ * @return array|null
+ */
+function p_cached_instructions($file,$cacheonly=false,$id='') {
+    static $run = null;
+    if(is_null($run)) $run = array();
+
+    $cache = new cache_instructions($id, $file);
+
+    if ($cacheonly || $cache->useCache() || (isset($run[$file]) && !defined('DOKU_UNITTEST'))) {
+        return $cache->retrieveCache();
+    } else if (file_exists($file)) {
+        // no cache - do some work
+        $ins = p_get_instructions(io_readWikiPage($file,$id));
+        if ($cache->storeCache($ins)) {
+            $run[$file] = true; // we won't rebuild these instructions in the same run again
+        } else {
+            msg('Unable to save cache file. Hint: disk full; file permissions; safe_mode setting.',-1);
+        }
+        return $ins;
+    }
+
+    return null;
+}
+
+/**
+ * turns a page into a list of instructions
+ *
+ * @author Harry Fuecks <hfuecks@gmail.com>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param string $text  raw wiki syntax text
+ * @return array a list of instruction arrays
+ */
+function p_get_instructions($text){
+
+    $modes = p_get_parsermodes();
+
+    // Create the parser
+    $Parser = new Doku_Parser();
+
+    // Add the Handler
+    $Parser->Handler = new Doku_Handler();
+
+    //add modes to parser
+    foreach($modes as $mode){
+        $Parser->addMode($mode['mode'],$mode['obj']);
+    }
+
+    // Do the parsing
+    trigger_event('PARSER_WIKITEXT_PREPROCESS', $text);
+    $p = $Parser->parse($text);
+    //  dbg($p);
+    return $p;
+}
+
+/**
+ * returns the metadata of a page
+ *
+ * @param string $id      The id of the page the metadata should be returned from
+ * @param string $key     The key of the metdata value that shall be read (by default everything) - separate hierarchies by " " like "date created"
+ * @param int    $render  If the page should be rendererd - possible values:
+ *     METADATA_DONT_RENDER, METADATA_RENDER_USING_SIMPLE_CACHE, METADATA_RENDER_USING_CACHE
+ *     METADATA_RENDER_UNLIMITED (also combined with the previous two options),
+ *     default: METADATA_RENDER_USING_CACHE
+ * @return mixed The requested metadata fields
+ *
+ * @author Esther Brunner <esther@kaffeehaus.ch>
+ * @author Michael Hamann <michael@content-space.de>
+ */
+function p_get_metadata($id, $key='', $render=METADATA_RENDER_USING_CACHE){
+    global $ID;
+    static $render_count = 0;
+    // track pages that have already been rendered in order to avoid rendering the same page
+    // again
+    static $rendered_pages = array();
+
+    // cache the current page
+    // Benchmarking shows the current page's metadata is generally the only page metadata
+    // accessed several times. This may catch a few other pages, but that shouldn't be an issue.
+    $cache = ($ID == $id);
+    $meta = p_read_metadata($id, $cache);
+
+    if (!is_numeric($render)) {
+        if ($render) {
+            $render = METADATA_RENDER_USING_SIMPLE_CACHE;
+        } else {
+            $render = METADATA_DONT_RENDER;
+        }
+    }
+
+    // prevent recursive calls in the cache
+    static $recursion = false;
+    if (!$recursion && $render != METADATA_DONT_RENDER && !isset($rendered_pages[$id])&& page_exists($id)){
+        $recursion = true;
+
+        $cachefile = new cache_renderer($id, wikiFN($id), 'metadata');
+
+        $do_render = false;
+        if ($render & METADATA_RENDER_UNLIMITED || $render_count < P_GET_METADATA_RENDER_LIMIT) {
+            if ($render & METADATA_RENDER_USING_SIMPLE_CACHE) {
+                $pagefn = wikiFN($id);
+                $metafn = metaFN($id, '.meta');
+                if (!file_exists($metafn) || @filemtime($pagefn) > @filemtime($cachefile->cache)) {
+                    $do_render = true;
+                }
+            } elseif (!$cachefile->useCache()){
+                $do_render = true;
+            }
+        }
+        if ($do_render) {
+            if (!defined('DOKU_UNITTEST')) {
+                ++$render_count;
+                $rendered_pages[$id] = true;
+            }
+            $old_meta = $meta;
+            $meta = p_render_metadata($id, $meta);
+            // only update the file when the metadata has been changed
+            if ($meta == $old_meta || p_save_metadata($id, $meta)) {
+                // store a timestamp in order to make sure that the cachefile is touched
+                // this timestamp is also stored when the meta data is still the same
+                $cachefile->storeCache(time());
+            } else {
+                msg('Unable to save metadata file. Hint: disk full; file permissions; safe_mode setting.',-1);
+            }
+        }
+
+        $recursion = false;
+    }
+
+    $val = $meta['current'];
+
+    // filter by $key
+    foreach(preg_split('/\s+/', $key, 2, PREG_SPLIT_NO_EMPTY) as $cur_key) {
+        if (!isset($val[$cur_key])) {
+            return null;
+        }
+        $val = $val[$cur_key];
+    }
+    return $val;
+}
+
+/**
+ * sets metadata elements of a page
+ *
+ * @see http://www.dokuwiki.org/devel:metadata#functions_to_get_and_set_metadata
+ *
+ * @param String  $id         is the ID of a wiki page
+ * @param Array   $data       is an array with key ⇒ value pairs to be set in the metadata
+ * @param Boolean $render     whether or not the page metadata should be generated with the renderer
+ * @param Boolean $persistent indicates whether or not the particular metadata value will persist through
+ *                            the next metadata rendering.
+ * @return boolean true on success
+ *
+ * @author Esther Brunner <esther@kaffeehaus.ch>
+ * @author Michael Hamann <michael@content-space.de>
+ */
+function p_set_metadata($id, $data, $render=false, $persistent=true){
+    if (!is_array($data)) return false;
+
+    global $ID, $METADATA_RENDERERS;
+
+    // if there is currently a renderer change the data in the renderer instead
+    if (isset($METADATA_RENDERERS[$id])) {
+        $orig =& $METADATA_RENDERERS[$id];
+        $meta = $orig;
+    } else {
+        // cache the current page
+        $cache = ($ID == $id);
+        $orig = p_read_metadata($id, $cache);
+
+        // render metadata first?
+        $meta = $render ? p_render_metadata($id, $orig) : $orig;
+    }
+
+    // now add the passed metadata
+    $protected = array('description', 'date', 'contributor');
+    foreach ($data as $key => $value){
+
+        // be careful with sub-arrays of $meta['relation']
+        if ($key == 'relation'){
+
+            foreach ($value as $subkey => $subvalue){
+                if(isset($meta['current'][$key][$subkey]) && is_array($meta['current'][$key][$subkey])) {
+                    $meta['current'][$key][$subkey] = array_replace($meta['current'][$key][$subkey], (array)$subvalue);
+                } else {
+                    $meta['current'][$key][$subkey] = $subvalue;
+                }
+                if($persistent) {
+                    if(isset($meta['persistent'][$key][$subkey]) && is_array($meta['persistent'][$key][$subkey])) {
+                        $meta['persistent'][$key][$subkey] = array_replace($meta['persistent'][$key][$subkey], (array)$subvalue);
+                    } else {
+                        $meta['persistent'][$key][$subkey] = $subvalue;
+                    }
+                }
+            }
+
+            // be careful with some senisitive arrays of $meta
+        } elseif (in_array($key, $protected)){
+
+            // these keys, must have subkeys - a legitimate value must be an array
+            if (is_array($value)) {
+                $meta['current'][$key] = !empty($meta['current'][$key]) ? array_replace((array)$meta['current'][$key],$value) : $value;
+
+                if ($persistent) {
+                    $meta['persistent'][$key] = !empty($meta['persistent'][$key]) ? array_replace((array)$meta['persistent'][$key],$value) : $value;
+                }
+            }
+
+            // no special treatment for the rest
+        } else {
+            $meta['current'][$key] = $value;
+            if ($persistent) $meta['persistent'][$key] = $value;
+        }
+    }
+
+    // save only if metadata changed
+    if ($meta == $orig) return true;
+
+    if (isset($METADATA_RENDERERS[$id])) {
+        // set both keys individually as the renderer has references to the individual keys
+        $METADATA_RENDERERS[$id]['current']    = $meta['current'];
+        $METADATA_RENDERERS[$id]['persistent'] = $meta['persistent'];
+        return true;
+    } else {
+        return p_save_metadata($id, $meta);
+    }
+}
+
+/**
+ * Purges the non-persistant part of the meta data
+ * used on page deletion
+ *
+ * @author Michael Klier <chi@chimeric.de>
+ *
+ * @param string $id page id
+ * @return bool  success / fail
+ */
+function p_purge_metadata($id) {
+    $meta = p_read_metadata($id);
+    foreach($meta['current'] as $key => $value) {
+        if(is_array($meta[$key])) {
+            $meta['current'][$key] = array();
+        } else {
+            $meta['current'][$key] = '';
+        }
+
+    }
+    return p_save_metadata($id, $meta);
+}
+
+/**
+ * read the metadata from source/cache for $id
+ * (internal use only - called by p_get_metadata & p_set_metadata)
+ *
+ * @author   Christopher Smith <chris@jalakai.co.uk>
+ *
+ * @param    string   $id      absolute wiki page id
+ * @param    bool     $cache   whether or not to cache metadata in memory
+ *                             (only use for metadata likely to be accessed several times)
+ *
+ * @return   array             metadata
+ */
+function p_read_metadata($id,$cache=false) {
+    global $cache_metadata;
+
+    if (isset($cache_metadata[(string)$id])) return $cache_metadata[(string)$id];
+
+    $file = metaFN($id, '.meta');
+    $meta = file_exists($file) ? unserialize(io_readFile($file, false)) : array('current'=>array(),'persistent'=>array());
+
+    if ($cache) {
+        $cache_metadata[(string)$id] = $meta;
+    }
+
+    return $meta;
+}
+
+/**
+ * This is the backend function to save a metadata array to a file
+ *
+ * @param    string   $id      absolute wiki page id
+ * @param    array    $meta    metadata
+ *
+ * @return   bool              success / fail
+ */
+function p_save_metadata($id, $meta) {
+    // sync cached copies, including $INFO metadata
+    global $cache_metadata, $INFO;
+
+    if (isset($cache_metadata[$id])) $cache_metadata[$id] = $meta;
+    if (!empty($INFO) && ($id == $INFO['id'])) { $INFO['meta'] = $meta['current']; }
+
+    return io_saveFile(metaFN($id, '.meta'), serialize($meta));
+}
+
+/**
+ * renders the metadata of a page
+ *
+ * @author Esther Brunner <esther@kaffeehaus.ch>
+ *
+ * @param string $id    page id
+ * @param array  $orig  the original metadata
+ * @return array|null array('current'=> array,'persistent'=> array);
+ */
+function p_render_metadata($id, $orig){
+    // make sure the correct ID is in global ID
+    global $ID, $METADATA_RENDERERS;
+
+    // avoid recursive rendering processes for the same id
+    if (isset($METADATA_RENDERERS[$id])) {
+        return $orig;
+    }
+
+    // store the original metadata in the global $METADATA_RENDERERS so p_set_metadata can use it
+    $METADATA_RENDERERS[$id] =& $orig;
+
+    $keep = $ID;
+    $ID   = $id;
+
+    // add an extra key for the event - to tell event handlers the page whose metadata this is
+    $orig['page'] = $id;
+    $evt = new Doku_Event('PARSER_METADATA_RENDER', $orig);
+    if ($evt->advise_before()) {
+
+        // get instructions
+        $instructions = p_cached_instructions(wikiFN($id),false,$id);
+        if(is_null($instructions)){
+            $ID = $keep;
+            unset($METADATA_RENDERERS[$id]);
+            return null; // something went wrong with the instructions
+        }
+
+        // set up the renderer
+        $renderer = new Doku_Renderer_metadata();
+        $renderer->meta =& $orig['current'];
+        $renderer->persistent =& $orig['persistent'];
+
+        // loop through the instructions
+        foreach ($instructions as $instruction){
+            // execute the callback against the renderer
+            call_user_func_array(array(&$renderer, $instruction[0]), (array) $instruction[1]);
+        }
+
+        $evt->result = array('current'=>&$renderer->meta,'persistent'=>&$renderer->persistent);
+    }
+    $evt->advise_after();
+
+    // clean up
+    $ID = $keep;
+    unset($METADATA_RENDERERS[$id]);
+    return $evt->result;
+}
+
+/**
+ * returns all available parser syntax modes in correct order
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @return array[] with for each plugin the array('sort' => sortnumber, 'mode' => mode string, 'obj'  => plugin object)
+ */
+function p_get_parsermodes(){
+    global $conf;
+
+    //reuse old data
+    static $modes = null;
+    if($modes != null && !defined('DOKU_UNITTEST')){
+        return $modes;
+    }
+
+    //import parser classes and mode definitions
+    require_once DOKU_INC . 'inc/parser/parser.php';
+
+    // we now collect all syntax modes and their objects, then they will
+    // be sorted and added to the parser in correct order
+    $modes = array();
+
+    // add syntax plugins
+    $pluginlist = plugin_list('syntax');
+    if(count($pluginlist)){
+        global $PARSER_MODES;
+        $obj = null;
+        foreach($pluginlist as $p){
+            /** @var DokuWiki_Syntax_Plugin $obj */
+            if(!$obj = plugin_load('syntax',$p)) continue; //attempt to load plugin into $obj
+            $PARSER_MODES[$obj->getType()][] = "plugin_$p"; //register mode type
+            //add to modes
+            $modes[] = array(
+                    'sort' => $obj->getSort(),
+                    'mode' => "plugin_$p",
+                    'obj'  => $obj,
+                    );
+            unset($obj); //remove the reference
+        }
+    }
+
+    // add default modes
+    $std_modes = array('listblock','preformatted','notoc','nocache',
+            'header','table','linebreak','footnote','hr',
+            'unformatted','php','html','code','file','quote',
+            'internallink','rss','media','externallink',
+            'emaillink','windowssharelink','eol');
+    if($conf['typography']){
+        $std_modes[] = 'quotes';
+        $std_modes[] = 'multiplyentity';
+    }
+    foreach($std_modes as $m){
+        $class = "Doku_Parser_Mode_$m";
+        $obj   = new $class();
+        $modes[] = array(
+                'sort' => $obj->getSort(),
+                'mode' => $m,
+                'obj'  => $obj
+                );
+    }
+
+    // add formatting modes
+    $fmt_modes = array('strong','emphasis','underline','monospace',
+            'subscript','superscript','deleted');
+    foreach($fmt_modes as $m){
+        $obj   = new Doku_Parser_Mode_formatting($m);
+        $modes[] = array(
+                'sort' => $obj->getSort(),
+                'mode' => $m,
+                'obj'  => $obj
+                );
+    }
+
+    // add modes which need files
+    $obj     = new Doku_Parser_Mode_smiley(array_keys(getSmileys()));
+    $modes[] = array('sort' => $obj->getSort(), 'mode' => 'smiley','obj'  => $obj );
+    $obj     = new Doku_Parser_Mode_acronym(array_keys(getAcronyms()));
+    $modes[] = array('sort' => $obj->getSort(), 'mode' => 'acronym','obj'  => $obj );
+    $obj     = new Doku_Parser_Mode_entity(array_keys(getEntities()));
+    $modes[] = array('sort' => $obj->getSort(), 'mode' => 'entity','obj'  => $obj );
+
+    // add optional camelcase mode
+    if($conf['camelcase']){
+        $obj     = new Doku_Parser_Mode_camelcaselink();
+        $modes[] = array('sort' => $obj->getSort(), 'mode' => 'camelcaselink','obj'  => $obj );
+    }
+
+    //sort modes
+    usort($modes,'p_sort_modes');
+
+    return $modes;
+}
+
+/**
+ * Callback function for usort
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param array $a
+ * @param array $b
+ * @return int $a is lower/equal/higher than $b
+ */
+function p_sort_modes($a, $b){
+    if($a['sort'] == $b['sort']) return 0;
+    return ($a['sort'] < $b['sort']) ? -1 : 1;
+}
+
+/**
+ * Renders a list of instruction to the specified output mode
+ *
+ * In the $info array is information from the renderer returned
+ *
+ * @author Harry Fuecks <hfuecks@gmail.com>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ *
+ * @param string $mode
+ * @param array|null|false $instructions
+ * @param array $info returns render info like enabled toc and cache
+ * @param string $date_at
+ * @return null|string rendered output
+ */
+function p_render($mode,$instructions,&$info,$date_at=''){
+    if(is_null($instructions)) return '';
+    if($instructions === false) return '';
+
+    $Renderer = p_get_renderer($mode);
+    if (is_null($Renderer)) return null;
+
+    $Renderer->reset();
+
+    if($date_at) {
+        $Renderer->date_at = $date_at;
+    }
+
+    $Renderer->smileys = getSmileys();
+    $Renderer->entities = getEntities();
+    $Renderer->acronyms = getAcronyms();
+    $Renderer->interwiki = getInterwiki();
+
+    // Loop through the instructions
+    foreach ( $instructions as $instruction ) {
+        // Execute the callback against the Renderer
+        if(method_exists($Renderer, $instruction[0])){
+            call_user_func_array(array(&$Renderer, $instruction[0]), $instruction[1] ? $instruction[1] : array());
+        }
+    }
+
+    //set info array
+    $info = $Renderer->info;
+
+    // Post process and return the output
+    $data = array($mode,& $Renderer->doc);
+    trigger_event('RENDERER_CONTENT_POSTPROCESS',$data);
+    return $Renderer->doc;
+}
+
+/**
+ * Figure out the correct renderer class to use for $mode,
+ * instantiate and return it
+ *
+ * @param string $mode Mode of the renderer to get
+ * @return null|Doku_Renderer The renderer
+ *
+ * @author Christopher Smith <chris@jalakai.co.uk>
+ */
+function p_get_renderer($mode) {
+    /** @var Doku_Plugin_Controller $plugin_controller */
+    global $conf, $plugin_controller;
+
+    $rname = !empty($conf['renderer_'.$mode]) ? $conf['renderer_'.$mode] : $mode;
+    $rclass = "Doku_Renderer_$rname";
+
+    // if requested earlier or a bundled renderer
+    if( class_exists($rclass) ) {
+        $Renderer = new $rclass();
+        return $Renderer;
+    }
+
+    // not bundled, see if its an enabled renderer plugin & when $mode is 'xhtml', the renderer can supply that format.
+    /** @var Doku_Renderer $Renderer */
+    $Renderer = $plugin_controller->load('renderer',$rname);
+    if ($Renderer && is_a($Renderer, 'Doku_Renderer')  && ($mode != 'xhtml' || $mode == $Renderer->getFormat())) {
+        return $Renderer;
+    }
+
+    // there is a configuration error!
+    // not bundled, not a valid enabled plugin, use $mode to try to fallback to a bundled renderer
+    $rclass = "Doku_Renderer_$mode";
+    if ( class_exists($rclass) ) {
+        // viewers should see renderered output, so restrict the warning to admins only
+        $msg = "No renderer '$rname' found for mode '$mode', check your plugins";
+        if ($mode == 'xhtml') {
+            $msg .= " and the 'renderer_xhtml' config setting";
+        }
+        $msg .= ".<br/>Attempting to fallback to the bundled renderer.";
+        msg($msg,-1,'','',MSG_ADMINS_ONLY);
+
+        $Renderer = new $rclass;
+        $Renderer->nocache();     // fallback only (and may include admin alerts), don't cache
+        return $Renderer;
+    }
+
+    // fallback failed, alert the world
+    msg("No renderer '$rname' found for mode '$mode'",-1);
+    return null;
+}
+
+/**
+ * Gets the first heading from a file
+ *
+ * @param   string   $id       dokuwiki page id
+ * @param   int      $render   rerender if first heading not known
+ *                             default: METADATA_RENDER_USING_SIMPLE_CACHE
+ *                             Possible values: METADATA_DONT_RENDER,
+ *                                              METADATA_RENDER_USING_SIMPLE_CACHE,
+ *                                              METADATA_RENDER_USING_CACHE,
+ *                                              METADATA_RENDER_UNLIMITED
+ * @return string|null The first heading
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
+ * @author Michael Hamann <michael@content-space.de>
+ */
+function p_get_first_heading($id, $render=METADATA_RENDER_USING_SIMPLE_CACHE){
+    return p_get_metadata(cleanID($id),'title',$render);
+}
+
+/**
+ * Wrapper for GeSHi Code Highlighter, provides caching of its output
+ *
+ * @param  string   $code       source code to be highlighted
+ * @param  string   $language   language to provide highlighting
+ * @param  string   $wrapper    html element to wrap the returned highlighted text
+ * @return string xhtml code
+ *
+ * @author Christopher Smith <chris@jalakai.co.uk>
+ * @author Andreas Gohr <andi@splitbrain.org>
+ */
+function p_xhtml_cached_geshi($code, $language, $wrapper='pre', array $options=null) {
+    global $conf, $config_cascade, $INPUT;
+    $language = strtolower($language);
+
+    // remove any leading or trailing blank lines
+    $code = preg_replace('/^\s*?\n|\s*?\n$/','',$code);
+
+    $optionsmd5 = md5(serialize($options));
+    $cache = getCacheName($language.$code.$optionsmd5,".code");
+    $ctime = @filemtime($cache);
+    if($ctime && !$INPUT->bool('purge') &&
+            $ctime > filemtime(DOKU_INC.'vendor/composer/installed.json') &&  // libraries changed
+            $ctime > filemtime(reset($config_cascade['main']['default']))){ // dokuwiki changed
+        $highlighted_code = io_readFile($cache, false);
+    } else {
+
+        $geshi = new GeSHi($code, $language);
+        $geshi->set_encoding('utf-8');
+        $geshi->enable_classes();
+        $geshi->set_header_type(GESHI_HEADER_PRE);
+        $geshi->set_link_target($conf['target']['extern']);
+        if($options !== null) {
+            foreach ($options as $function => $params) {
+                if(is_callable(array($geshi, $function))) {
+                    $geshi->$function($params);
+                }
+            }
+        }
+
+        // remove GeSHi's wrapper element (we'll replace it with our own later)
+        // we need to use a GeSHi wrapper to avoid <BR> throughout the highlighted text
+        $highlighted_code = trim(preg_replace('!^<pre[^>]*>|</pre>$!','',$geshi->parse_code()),"\n\r");
+        io_saveFile($cache,$highlighted_code);
+    }
+
+    // add a wrapper element if required
+    if ($wrapper) {
+        return "<$wrapper class=\"code $language\">$highlighted_code</$wrapper>";
+    } else {
+        return $highlighted_code;
+    }
+}
+