xref: /dokuwiki/inc/common.php (revision a81f3d99fc1bb57989fc0acb0ed72fc168bb74ad) 
1<?php
2/**
3 * Common DokuWiki functions
4 *
5 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
6 * @author     Andreas Gohr <andi@splitbrain.org>
7 */
8
9if(!defined('DOKU_INC')) die('meh.');
10
11/**
12 * These constants are used with the recents function
13 */
14define('RECENTS_SKIP_DELETED', 2);
15define('RECENTS_SKIP_MINORS', 4);
16define('RECENTS_SKIP_SUBSPACES', 8);
17define('RECENTS_MEDIA_CHANGES', 16);
18define('RECENTS_MEDIA_PAGES_MIXED', 32);
19
20/**
21 * Wrapper around htmlspecialchars()
22 *
23 * @author Andreas Gohr <andi@splitbrain.org>
24 * @see    htmlspecialchars()
25 *
26 * @param string $string the string being converted
27 * @return string converted string
28 */
29function hsc($string) {
30    return htmlspecialchars($string, ENT_QUOTES, 'UTF-8');
31}
32
33/**
34 * Checks if the given input is blank
35 *
36 * This is similar to empty() but will return false for "0".
37 *
38 * Please note: when you pass uninitialized variables, they will implicitly be created
39 * with a NULL value without warning.
40 *
41 * To avoid this it's recommended to guard the call with isset like this:
42 *
43 * (isset($foo) && !blank($foo))
44 * (!isset($foo) || blank($foo))
45 *
46 * @param $in
47 * @param bool $trim Consider a string of whitespace to be blank
48 * @return bool
49 */
50function blank(&$in, $trim = false) {
51    if(is_null($in)) return true;
52    if(is_array($in)) return empty($in);
53    if($in === "\0") return true;
54    if($trim && trim($in) === '') return true;
55    if(strlen($in) > 0) return false;
56    return empty($in);
57}
58
59/**
60 * print a newline terminated string
61 *
62 * You can give an indention as optional parameter
63 *
64 * @author Andreas Gohr <andi@splitbrain.org>
65 *
66 * @param string $string  line of text
67 * @param int    $indent  number of spaces indention
68 */
69function ptln($string, $indent = 0) {
70    echo str_repeat(' ', $indent)."$string\n";
71}
72
73/**
74 * strips control characters (<32) from the given string
75 *
76 * @author Andreas Gohr <andi@splitbrain.org>
77 *
78 * @param string $string being stripped
79 * @return string
80 */
81function stripctl($string) {
82    return preg_replace('/[\x00-\x1F]+/s', '', $string);
83}
84
85/**
86 * Return a secret token to be used for CSRF attack prevention
87 *
88 * @author  Andreas Gohr <andi@splitbrain.org>
89 * @link    http://en.wikipedia.org/wiki/Cross-site_request_forgery
90 * @link    http://christ1an.blogspot.com/2007/04/preventing-csrf-efficiently.html
91 *
92 * @return  string
93 */
94function getSecurityToken() {
95    /** @var Input $INPUT */
96    global $INPUT;
97
98    $user = $INPUT->server->str('REMOTE_USER');
99    $session = session_id();
100
101    // CSRF checks are only for logged in users - do not generate for anonymous
102    if(trim($user) == '' || trim($session) == '') return '';
103    return PassHash::hmac('md5', $session.$user, auth_cookiesalt());
104}
105
106/**
107 * Check the secret CSRF token
108 *
109 * @param null|string $token security token or null to read it from request variable
110 * @return bool success if the token matched
111 */
112function checkSecurityToken($token = null) {
113    /** @var Input $INPUT */
114    global $INPUT;
115    if(!$INPUT->server->str('REMOTE_USER')) return true; // no logged in user, no need for a check
116
117    if(is_null($token)) $token = $INPUT->str('sectok');
118    if(getSecurityToken() != $token) {
119        msg('Security Token did not match. Possible CSRF attack.', -1);
120        return false;
121    }
122    return true;
123}
124
125/**
126 * Print a hidden form field with a secret CSRF token
127 *
128 * @author  Andreas Gohr <andi@splitbrain.org>
129 *
130 * @param bool $print  if true print the field, otherwise html of the field is returned
131 * @return string html of hidden form field
132 */
133function formSecurityToken($print = true) {
134    $ret = '<div class="no"><input type="hidden" name="sectok" value="'.getSecurityToken().'" /></div>'."\n";
135    if($print) echo $ret;
136    return $ret;
137}
138
139/**
140 * Determine basic information for a request of $id
141 *
142 * @author Andreas Gohr <andi@splitbrain.org>
143 * @author Chris Smith <chris@jalakai.co.uk>
144 *
145 * @param string $id         pageid
146 * @param bool   $htmlClient add info about whether is mobile browser
147 * @return array with info for a request of $id
148 *
149 */
150function basicinfo($id, $htmlClient=true){
151    global $USERINFO;
152    /* @var Input $INPUT */
153    global $INPUT;
154
155    // set info about manager/admin status.
156    $info = array();
157    $info['isadmin']   = false;
158    $info['ismanager'] = false;
159    if($INPUT->server->has('REMOTE_USER')) {
160        $info['userinfo']   = $USERINFO;
161        $info['perm']       = auth_quickaclcheck($id);
162        $info['client']     = $INPUT->server->str('REMOTE_USER');
163
164        if($info['perm'] == AUTH_ADMIN) {
165            $info['isadmin']   = true;
166            $info['ismanager'] = true;
167        } elseif(auth_ismanager()) {
168            $info['ismanager'] = true;
169        }
170
171        // if some outside auth were used only REMOTE_USER is set
172        if(!$info['userinfo']['name']) {
173            $info['userinfo']['name'] = $INPUT->server->str('REMOTE_USER');
174        }
175
176    } else {
177        $info['perm']       = auth_aclcheck($id, '', null);
178        $info['client']     = clientIP(true);
179    }
180
181    $info['namespace'] = getNS($id);
182
183    // mobile detection
184    if ($htmlClient) {
185        $info['ismobile'] = clientismobile();
186    }
187
188    return $info;
189 }
190
191/**
192 * Return info about the current document as associative
193 * array.
194 *
195 * @author Andreas Gohr <andi@splitbrain.org>
196 *
197 * @return array with info about current document
198 */
199function pageinfo() {
200    global $ID;
201    global $REV;
202    global $RANGE;
203    global $lang;
204    /* @var Input $INPUT */
205    global $INPUT;
206
207    $info = basicinfo($ID);
208
209    // include ID & REV not redundant, as some parts of DokuWiki may temporarily change $ID, e.g. p_wiki_xhtml
210    // FIXME ... perhaps it would be better to ensure the temporary changes weren't necessary
211    $info['id']  = $ID;
212    $info['rev'] = $REV;
213
214    if($INPUT->server->has('REMOTE_USER')) {
215        $sub = new Subscription();
216        $info['subscribed'] = $sub->user_subscription();
217    } else {
218        $info['subscribed'] = false;
219    }
220
221    $info['locked']     = checklock($ID);
222    $info['filepath']   = wikiFN($ID);
223    $info['exists']     = file_exists($info['filepath']);
224    $info['currentrev'] = @filemtime($info['filepath']);
225    if($REV) {
226        //check if current revision was meant
227        if($info['exists'] && ($info['currentrev'] == $REV)) {
228            $REV = '';
229        } elseif($RANGE) {
230            //section editing does not work with old revisions!
231            $REV   = '';
232            $RANGE = '';
233            msg($lang['nosecedit'], 0);
234        } else {
235            //really use old revision
236            $info['filepath'] = wikiFN($ID, $REV);
237            $info['exists']   = file_exists($info['filepath']);
238        }
239    }
240    $info['rev'] = $REV;
241    if($info['exists']) {
242        $info['writable'] = (is_writable($info['filepath']) &&
243            ($info['perm'] >= AUTH_EDIT));
244    } else {
245        $info['writable'] = ($info['perm'] >= AUTH_CREATE);
246    }
247    $info['editable'] = ($info['writable'] && empty($info['locked']));
248    $info['lastmod']  = @filemtime($info['filepath']);
249
250    //load page meta data
251    $info['meta'] = p_get_metadata($ID);
252
253    //who's the editor
254    $pagelog = new PageChangeLog($ID, 1024);
255    if($REV) {
256        $revinfo = $pagelog->getRevisionInfo($REV);
257    } else {
258        if(!empty($info['meta']['last_change']) && is_array($info['meta']['last_change'])) {
259            $revinfo = $info['meta']['last_change'];
260        } else {
261            $revinfo = $pagelog->getRevisionInfo($info['lastmod']);
262            // cache most recent changelog line in metadata if missing and still valid
263            if($revinfo !== false) {
264                $info['meta']['last_change'] = $revinfo;
265                p_set_metadata($ID, array('last_change' => $revinfo));
266            }
267        }
268    }
269    //and check for an external edit
270    if($revinfo !== false && $revinfo['date'] != $info['lastmod']) {
271        // cached changelog line no longer valid
272        $revinfo                     = false;
273        $info['meta']['last_change'] = $revinfo;
274        p_set_metadata($ID, array('last_change' => $revinfo));
275    }
276
277    $info['ip']   = $revinfo['ip'];
278    $info['user'] = $revinfo['user'];
279    $info['sum']  = $revinfo['sum'];
280    // See also $INFO['meta']['last_change'] which is the most recent log line for page $ID.
281    // Use $INFO['meta']['last_change']['type']===DOKU_CHANGE_TYPE_MINOR_EDIT in place of $info['minor'].
282
283    if($revinfo['user']) {
284        $info['editor'] = $revinfo['user'];
285    } else {
286        $info['editor'] = $revinfo['ip'];
287    }
288
289    // draft
290    $draft = new \dokuwiki\Draft($ID, $info['client']);
291    if ($draft->isDraftAvailable()) {
292        $info['draft'] = $draft->getDraftFilename();
293    }
294
295    return $info;
296}
297
298/**
299 * Initialize and/or fill global $JSINFO with some basic info to be given to javascript
300 */
301function jsinfo() {
302    global $JSINFO, $ID, $INFO, $ACT;
303
304    if (!is_array($JSINFO)) {
305        $JSINFO = [];
306    }
307    //export minimal info to JS, plugins can add more
308    $JSINFO['id']                    = $ID;
309    $JSINFO['namespace']             = (string) $INFO['namespace'];
310    $JSINFO['ACT']                   = act_clean($ACT);
311    $JSINFO['useHeadingNavigation']  = (int) useHeading('navigation');
312    $JSINFO['useHeadingContent']     = (int) useHeading('content');
313}
314
315/**
316 * Return information about the current media item as an associative array.
317 *
318 * @return array with info about current media item
319 */
320function mediainfo(){
321    global $NS;
322    global $IMG;
323
324    $info = basicinfo("$NS:*");
325    $info['image'] = $IMG;
326
327    return $info;
328}
329
330/**
331 * Build an string of URL parameters
332 *
333 * @author Andreas Gohr
334 *
335 * @param array  $params    array with key-value pairs
336 * @param string $sep       series of pairs are separated by this character
337 * @return string query string
338 */
339function buildURLparams($params, $sep = '&amp;') {
340    $url = '';
341    $amp = false;
342    foreach($params as $key => $val) {
343        if($amp) $url .= $sep;
344
345        $url .= rawurlencode($key).'=';
346        $url .= rawurlencode((string) $val);
347        $amp = true;
348    }
349    return $url;
350}
351
352/**
353 * Build an string of html tag attributes
354 *
355 * Skips keys starting with '_', values get HTML encoded
356 *
357 * @author Andreas Gohr
358 *
359 * @param array $params    array with (attribute name-attribute value) pairs
360 * @param bool  $skipempty skip empty string values?
361 * @return string
362 */
363function buildAttributes($params, $skipempty = false) {
364    $url   = '';
365    $white = false;
366    foreach($params as $key => $val) {
367        if($key{0} == '_') continue;
368        if($val === '' && $skipempty) continue;
369        if($white) $url .= ' ';
370
371        $url .= $key.'="';
372        $url .= htmlspecialchars($val);
373        $url .= '"';
374        $white = true;
375    }
376    return $url;
377}
378
379/**
380 * This builds the breadcrumb trail and returns it as array
381 *
382 * @author Andreas Gohr <andi@splitbrain.org>
383 *
384 * @return string[] with the data: array(pageid=>name, ... )
385 */
386function breadcrumbs() {
387    // we prepare the breadcrumbs early for quick session closing
388    static $crumbs = null;
389    if($crumbs != null) return $crumbs;
390
391    global $ID;
392    global $ACT;
393    global $conf;
394
395    //first visit?
396    $crumbs = isset($_SESSION[DOKU_COOKIE]['bc']) ? $_SESSION[DOKU_COOKIE]['bc'] : array();
397    //we only save on show and existing visible wiki documents
398    $file = wikiFN($ID);
399    if($ACT != 'show' || isHiddenPage($ID) || !file_exists($file)) {
400        $_SESSION[DOKU_COOKIE]['bc'] = $crumbs;
401        return $crumbs;
402    }
403
404    // page names
405    $name = noNSorNS($ID);
406    if(useHeading('navigation')) {
407        // get page title
408        $title = p_get_first_heading($ID, METADATA_RENDER_USING_SIMPLE_CACHE);
409        if($title) {
410            $name = $title;
411        }
412    }
413
414    //remove ID from array
415    if(isset($crumbs[$ID])) {
416        unset($crumbs[$ID]);
417    }
418
419    //add to array
420    $crumbs[$ID] = $name;
421    //reduce size
422    while(count($crumbs) > $conf['breadcrumbs']) {
423        array_shift($crumbs);
424    }
425    //save to session
426    $_SESSION[DOKU_COOKIE]['bc'] = $crumbs;
427    return $crumbs;
428}
429
430/**
431 * Filter for page IDs
432 *
433 * This is run on a ID before it is outputted somewhere
434 * currently used to replace the colon with something else
435 * on Windows (non-IIS) systems and to have proper URL encoding
436 *
437 * See discussions at https://github.com/splitbrain/dokuwiki/pull/84 and
438 * https://github.com/splitbrain/dokuwiki/pull/173 why we use a whitelist of
439 * unaffected servers instead of blacklisting affected servers here.
440 *
441 * Urlencoding is ommitted when the second parameter is false
442 *
443 * @author Andreas Gohr <andi@splitbrain.org>
444 *
445 * @param string $id pageid being filtered
446 * @param bool   $ue apply urlencoding?
447 * @return string
448 */
449function idfilter($id, $ue = true) {
450    global $conf;
451    /* @var Input $INPUT */
452    global $INPUT;
453
454    if($conf['useslash'] && $conf['userewrite']) {
455        $id = strtr($id, ':', '/');
456    } elseif(strtoupper(substr(PHP_OS, 0, 3)) === 'WIN' &&
457        $conf['userewrite'] &&
458        strpos($INPUT->server->str('SERVER_SOFTWARE'), 'Microsoft-IIS') === false
459    ) {
460        $id = strtr($id, ':', ';');
461    }
462    if($ue) {
463        $id = rawurlencode($id);
464        $id = str_replace('%3A', ':', $id); //keep as colon
465        $id = str_replace('%3B', ';', $id); //keep as semicolon
466        $id = str_replace('%2F', '/', $id); //keep as slash
467    }
468    return $id;
469}
470
471/**
472 * This builds a link to a wikipage
473 *
474 * It handles URL rewriting and adds additional parameters
475 *
476 * @author Andreas Gohr <andi@splitbrain.org>
477 *
478 * @param string       $id             page id, defaults to start page
479 * @param string|array $urlParameters  URL parameters, associative array recommended
480 * @param bool         $absolute       request an absolute URL instead of relative
481 * @param string       $separator      parameter separator
482 * @return string
483 */
484function wl($id = '', $urlParameters = '', $absolute = false, $separator = '&amp;') {
485    global $conf;
486    if(is_array($urlParameters)) {
487        if(isset($urlParameters['rev']) && !$urlParameters['rev']) unset($urlParameters['rev']);
488        if(isset($urlParameters['at']) && $conf['date_at_format']) $urlParameters['at'] = date($conf['date_at_format'],$urlParameters['at']);
489        $urlParameters = buildURLparams($urlParameters, $separator);
490    } else {
491        $urlParameters = str_replace(',', $separator, $urlParameters);
492    }
493    if($id === '') {
494        $id = $conf['start'];
495    }
496    $id = idfilter($id);
497    if($absolute) {
498        $xlink = DOKU_URL;
499    } else {
500        $xlink = DOKU_BASE;
501    }
502
503    if($conf['userewrite'] == 2) {
504        $xlink .= DOKU_SCRIPT.'/'.$id;
505        if($urlParameters) $xlink .= '?'.$urlParameters;
506    } elseif($conf['userewrite']) {
507        $xlink .= $id;
508        if($urlParameters) $xlink .= '?'.$urlParameters;
509    } elseif($id !== '') {
510        $xlink .= DOKU_SCRIPT.'?id='.$id;
511        if($urlParameters) $xlink .= $separator.$urlParameters;
512    } else {
513        $xlink .= DOKU_SCRIPT;
514        if($urlParameters) $xlink .= '?'.$urlParameters;
515    }
516
517    return $xlink;
518}
519
520/**
521 * This builds a link to an alternate page format
522 *
523 * Handles URL rewriting if enabled. Follows the style of wl().
524 *
525 * @author Ben Coburn <btcoburn@silicodon.net>
526 * @param string       $id             page id, defaults to start page
527 * @param string       $format         the export renderer to use
528 * @param string|array $urlParameters  URL parameters, associative array recommended
529 * @param bool         $abs            request an absolute URL instead of relative
530 * @param string       $sep            parameter separator
531 * @return string
532 */
533function exportlink($id = '', $format = 'raw', $urlParameters = '', $abs = false, $sep = '&amp;') {
534    global $conf;
535    if(is_array($urlParameters)) {
536        $urlParameters = buildURLparams($urlParameters, $sep);
537    } else {
538        $urlParameters = str_replace(',', $sep, $urlParameters);
539    }
540
541    $format = rawurlencode($format);
542    $id     = idfilter($id);
543    if($abs) {
544        $xlink = DOKU_URL;
545    } else {
546        $xlink = DOKU_BASE;
547    }
548
549    if($conf['userewrite'] == 2) {
550        $xlink .= DOKU_SCRIPT.'/'.$id.'?do=export_'.$format;
551        if($urlParameters) $xlink .= $sep.$urlParameters;
552    } elseif($conf['userewrite'] == 1) {
553        $xlink .= '_export/'.$format.'/'.$id;
554        if($urlParameters) $xlink .= '?'.$urlParameters;
555    } else {
556        $xlink .= DOKU_SCRIPT.'?do=export_'.$format.$sep.'id='.$id;
557        if($urlParameters) $xlink .= $sep.$urlParameters;
558    }
559
560    return $xlink;
561}
562
563/**
564 * Build a link to a media file
565 *
566 * Will return a link to the detail page if $direct is false
567 *
568 * The $more parameter should always be given as array, the function then
569 * will strip default parameters to produce even cleaner URLs
570 *
571 * @param string  $id     the media file id or URL
572 * @param mixed   $more   string or array with additional parameters
573 * @param bool    $direct link to detail page if false
574 * @param string  $sep    URL parameter separator
575 * @param bool    $abs    Create an absolute URL
576 * @return string
577 */
578function ml($id = '', $more = '', $direct = true, $sep = '&amp;', $abs = false) {
579    global $conf;
580    $isexternalimage = media_isexternal($id);
581    if(!$isexternalimage) {
582        $id = cleanID($id);
583    }
584
585    if(is_array($more)) {
586        // add token for resized images
587        if(!empty($more['w']) || !empty($more['h']) || $isexternalimage){
588            $more['tok'] = media_get_token($id,$more['w'],$more['h']);
589        }
590        // strip defaults for shorter URLs
591        if(isset($more['cache']) && $more['cache'] == 'cache') unset($more['cache']);
592        if(empty($more['w'])) unset($more['w']);
593        if(empty($more['h'])) unset($more['h']);
594        if(isset($more['id']) && $direct) unset($more['id']);
595        if(isset($more['rev']) && !$more['rev']) unset($more['rev']);
596        $more = buildURLparams($more, $sep);
597    } else {
598        $matches = array();
599        if (preg_match_all('/\b(w|h)=(\d*)\b/',$more,$matches,PREG_SET_ORDER) || $isexternalimage){
600            $resize = array('w'=>0, 'h'=>0);
601            foreach ($matches as $match){
602                $resize[$match[1]] = $match[2];
603            }
604            $more .= $more === '' ? '' : $sep;
605            $more .= 'tok='.media_get_token($id,$resize['w'],$resize['h']);
606        }
607        $more = str_replace('cache=cache', '', $more); //skip default
608        $more = str_replace(',,', ',', $more);
609        $more = str_replace(',', $sep, $more);
610    }
611
612    if($abs) {
613        $xlink = DOKU_URL;
614    } else {
615        $xlink = DOKU_BASE;
616    }
617
618    // external URLs are always direct without rewriting
619    if($isexternalimage) {
620        $xlink .= 'lib/exe/fetch.php';
621        $xlink .= '?'.$more;
622        $xlink .= $sep.'media='.rawurlencode($id);
623        return $xlink;
624    }
625
626    $id = idfilter($id);
627
628    // decide on scriptname
629    if($direct) {
630        if($conf['userewrite'] == 1) {
631            $script = '_media';
632        } else {
633            $script = 'lib/exe/fetch.php';
634        }
635    } else {
636        if($conf['userewrite'] == 1) {
637            $script = '_detail';
638        } else {
639            $script = 'lib/exe/detail.php';
640        }
641    }
642
643    // build URL based on rewrite mode
644    if($conf['userewrite']) {
645        $xlink .= $script.'/'.$id;
646        if($more) $xlink .= '?'.$more;
647    } else {
648        if($more) {
649            $xlink .= $script.'?'.$more;
650            $xlink .= $sep.'media='.$id;
651        } else {
652            $xlink .= $script.'?media='.$id;
653        }
654    }
655
656    return $xlink;
657}
658
659/**
660 * Returns the URL to the DokuWiki base script
661 *
662 * Consider using wl() instead, unless you absoutely need the doku.php endpoint
663 *
664 * @author Andreas Gohr <andi@splitbrain.org>
665 *
666 * @return string
667 */
668function script() {
669    return DOKU_BASE.DOKU_SCRIPT;
670}
671
672/**
673 * Spamcheck against wordlist
674 *
675 * Checks the wikitext against a list of blocked expressions
676 * returns true if the text contains any bad words
677 *
678 * Triggers COMMON_WORDBLOCK_BLOCKED
679 *
680 *  Action Plugins can use this event to inspect the blocked data
681 *  and gain information about the user who was blocked.
682 *
683 *  Event data:
684 *    data['matches']  - array of matches
685 *    data['userinfo'] - information about the blocked user
686 *      [ip]           - ip address
687 *      [user]         - username (if logged in)
688 *      [mail]         - mail address (if logged in)
689 *      [name]         - real name (if logged in)
690 *
691 * @author Andreas Gohr <andi@splitbrain.org>
692 * @author Michael Klier <chi@chimeric.de>
693 *
694 * @param  string $text - optional text to check, if not given the globals are used
695 * @return bool         - true if a spam word was found
696 */
697function checkwordblock($text = '') {
698    global $TEXT;
699    global $PRE;
700    global $SUF;
701    global $SUM;
702    global $conf;
703    global $INFO;
704    /* @var Input $INPUT */
705    global $INPUT;
706
707    if(!$conf['usewordblock']) return false;
708
709    if(!$text) $text = "$PRE $TEXT $SUF $SUM";
710
711    // we prepare the text a tiny bit to prevent spammers circumventing URL checks
712    $text = preg_replace('!(\b)(www\.[\w.:?\-;,]+?\.[\w.:?\-;,]+?[\w/\#~:.?+=&%@\!\-.:?\-;,]+?)([.:?\-;,]*[^\w/\#~:.?+=&%@\!\-.:?\-;,])!i', '\1http://\2 \2\3', $text);
713
714    $wordblocks = getWordblocks();
715    // how many lines to read at once (to work around some PCRE limits)
716    if(version_compare(phpversion(), '4.3.0', '<')) {
717        // old versions of PCRE define a maximum of parenthesises even if no
718        // backreferences are used - the maximum is 99
719        // this is very bad performancewise and may even be too high still
720        $chunksize = 40;
721    } else {
722        // read file in chunks of 200 - this should work around the
723        // MAX_PATTERN_SIZE in modern PCRE
724        $chunksize = 200;
725    }
726    while($blocks = array_splice($wordblocks, 0, $chunksize)) {
727        $re = array();
728        // build regexp from blocks
729        foreach($blocks as $block) {
730            $block = preg_replace('/#.*$/', '', $block);
731            $block = trim($block);
732            if(empty($block)) continue;
733            $re[] = $block;
734        }
735        if(count($re) && preg_match('#('.join('|', $re).')#si', $text, $matches)) {
736            // prepare event data
737            $data = array();
738            $data['matches']        = $matches;
739            $data['userinfo']['ip'] = $INPUT->server->str('REMOTE_ADDR');
740            if($INPUT->server->str('REMOTE_USER')) {
741                $data['userinfo']['user'] = $INPUT->server->str('REMOTE_USER');
742                $data['userinfo']['name'] = $INFO['userinfo']['name'];
743                $data['userinfo']['mail'] = $INFO['userinfo']['mail'];
744            }
745            $callback = function () {
746                return true;
747            };
748            return trigger_event('COMMON_WORDBLOCK_BLOCKED', $data, $callback, true);
749        }
750    }
751    return false;
752}
753
754/**
755 * Return the IP of the client
756 *
757 * Honours X-Forwarded-For and X-Real-IP Proxy Headers
758 *
759 * It returns a comma separated list of IPs if the above mentioned
760 * headers are set. If the single parameter is set, it tries to return
761 * a routable public address, prefering the ones suplied in the X
762 * headers
763 *
764 * @author Andreas Gohr <andi@splitbrain.org>
765 *
766 * @param  boolean $single If set only a single IP is returned
767 * @return string
768 */
769function clientIP($single = false) {
770    /* @var Input $INPUT */
771    global $INPUT;
772
773    $ip   = array();
774    $ip[] = $INPUT->server->str('REMOTE_ADDR');
775    if($INPUT->server->str('HTTP_X_FORWARDED_FOR')) {
776        $ip = array_merge($ip, explode(',', str_replace(' ', '', $INPUT->server->str('HTTP_X_FORWARDED_FOR'))));
777    }
778    if($INPUT->server->str('HTTP_X_REAL_IP')) {
779        $ip = array_merge($ip, explode(',', str_replace(' ', '', $INPUT->server->str('HTTP_X_REAL_IP'))));
780    }
781
782    // some IPv4/v6 regexps borrowed from Feyd
783    // see: http://forums.devnetwork.net/viewtopic.php?f=38&t=53479
784    $dec_octet   = '(?:25[0-5]|2[0-4]\d|1\d\d|[1-9]\d|[0-9])';
785    $hex_digit   = '[A-Fa-f0-9]';
786    $h16         = "{$hex_digit}{1,4}";
787    $IPv4Address = "$dec_octet\\.$dec_octet\\.$dec_octet\\.$dec_octet";
788    $ls32        = "(?:$h16:$h16|$IPv4Address)";
789    $IPv6Address =
790        "(?:(?:{$IPv4Address})|(?:".
791            "(?:$h16:){6}$ls32".
792            "|::(?:$h16:){5}$ls32".
793            "|(?:$h16)?::(?:$h16:){4}$ls32".
794            "|(?:(?:$h16:){0,1}$h16)?::(?:$h16:){3}$ls32".
795            "|(?:(?:$h16:){0,2}$h16)?::(?:$h16:){2}$ls32".
796            "|(?:(?:$h16:){0,3}$h16)?::(?:$h16:){1}$ls32".
797            "|(?:(?:$h16:){0,4}$h16)?::$ls32".
798            "|(?:(?:$h16:){0,5}$h16)?::$h16".
799            "|(?:(?:$h16:){0,6}$h16)?::".
800            ")(?:\\/(?:12[0-8]|1[0-1][0-9]|[1-9][0-9]|[0-9]))?)";
801
802    // remove any non-IP stuff
803    $cnt   = count($ip);
804    $match = array();
805    for($i = 0; $i < $cnt; $i++) {
806        if(preg_match("/^$IPv4Address$/", $ip[$i], $match) || preg_match("/^$IPv6Address$/", $ip[$i], $match)) {
807            $ip[$i] = $match[0];
808        } else {
809            $ip[$i] = '';
810        }
811        if(empty($ip[$i])) unset($ip[$i]);
812    }
813    $ip = array_values(array_unique($ip));
814    if(!$ip[0]) $ip[0] = '0.0.0.0'; // for some strange reason we don't have a IP
815
816    if(!$single) return join(',', $ip);
817
818    // decide which IP to use, trying to avoid local addresses
819    $ip = array_reverse($ip);
820    foreach($ip as $i) {
821        if(preg_match('/^(::1|[fF][eE]80:|127\.|10\.|192\.168\.|172\.((1[6-9])|(2[0-9])|(3[0-1]))\.)/', $i)) {
822            continue;
823        } else {
824            return $i;
825        }
826    }
827    // still here? just use the first (last) address
828    return $ip[0];
829}
830
831/**
832 * Check if the browser is on a mobile device
833 *
834 * Adapted from the example code at url below
835 *
836 * @link http://www.brainhandles.com/2007/10/15/detecting-mobile-browsers/#code
837 *
838 * @return bool if true, client is mobile browser; otherwise false
839 */
840function clientismobile() {
841    /* @var Input $INPUT */
842    global $INPUT;
843
844    if($INPUT->server->has('HTTP_X_WAP_PROFILE')) return true;
845
846    if(preg_match('/wap\.|\.wap/i', $INPUT->server->str('HTTP_ACCEPT'))) return true;
847
848    if(!$INPUT->server->has('HTTP_USER_AGENT')) return false;
849
850    $uamatches = 'midp|j2me|avantg|docomo|novarra|palmos|palmsource|240x320|opwv|chtml|pda|windows ce|mmp\/|blackberry|mib\/|symbian|wireless|nokia|hand|mobi|phone|cdm|up\.b|audio|SIE\-|SEC\-|samsung|HTC|mot\-|mitsu|sagem|sony|alcatel|lg|erics|vx|NEC|philips|mmm|xx|panasonic|sharp|wap|sch|rover|pocket|benq|java|pt|pg|vox|amoi|bird|compal|kg|voda|sany|kdd|dbt|sendo|sgh|gradi|jb|\d\d\di|moto';
851
852    if(preg_match("/$uamatches/i", $INPUT->server->str('HTTP_USER_AGENT'))) return true;
853
854    return false;
855}
856
857/**
858 * check if a given link is interwiki link
859 *
860 * @param string $link the link, e.g. "wiki>page"
861 * @return bool
862 */
863function link_isinterwiki($link){
864    if (preg_match('/^[a-zA-Z0-9\.]+>/u',$link)) return true;
865    return false;
866}
867
868/**
869 * Convert one or more comma separated IPs to hostnames
870 *
871 * If $conf['dnslookups'] is disabled it simply returns the input string
872 *
873 * @author Glen Harris <astfgl@iamnota.org>
874 *
875 * @param  string $ips comma separated list of IP addresses
876 * @return string a comma separated list of hostnames
877 */
878function gethostsbyaddrs($ips) {
879    global $conf;
880    if(!$conf['dnslookups']) return $ips;
881
882    $hosts = array();
883    $ips   = explode(',', $ips);
884
885    if(is_array($ips)) {
886        foreach($ips as $ip) {
887            $hosts[] = gethostbyaddr(trim($ip));
888        }
889        return join(',', $hosts);
890    } else {
891        return gethostbyaddr(trim($ips));
892    }
893}
894
895/**
896 * Checks if a given page is currently locked.
897 *
898 * removes stale lockfiles
899 *
900 * @author Andreas Gohr <andi@splitbrain.org>
901 *
902 * @param string $id page id
903 * @return bool page is locked?
904 */
905function checklock($id) {
906    global $conf;
907    /* @var Input $INPUT */
908    global $INPUT;
909
910    $lock = wikiLockFN($id);
911
912    //no lockfile
913    if(!file_exists($lock)) return false;
914
915    //lockfile expired
916    if((time() - filemtime($lock)) > $conf['locktime']) {
917        @unlink($lock);
918        return false;
919    }
920
921    //my own lock
922    @list($ip, $session) = explode("\n", io_readFile($lock));
923    if($ip == $INPUT->server->str('REMOTE_USER') || $ip == clientIP() || (session_id() && $session == session_id())) {
924        return false;
925    }
926
927    return $ip;
928}
929
930/**
931 * Lock a page for editing
932 *
933 * @author Andreas Gohr <andi@splitbrain.org>
934 *
935 * @param string $id page id to lock
936 */
937function lock($id) {
938    global $conf;
939    /* @var Input $INPUT */
940    global $INPUT;
941
942    if($conf['locktime'] == 0) {
943        return;
944    }
945
946    $lock = wikiLockFN($id);
947    if($INPUT->server->str('REMOTE_USER')) {
948        io_saveFile($lock, $INPUT->server->str('REMOTE_USER'));
949    } else {
950        io_saveFile($lock, clientIP()."\n".session_id());
951    }
952}
953
954/**
955 * Unlock a page if it was locked by the user
956 *
957 * @author Andreas Gohr <andi@splitbrain.org>
958 *
959 * @param string $id page id to unlock
960 * @return bool true if a lock was removed
961 */
962function unlock($id) {
963    /* @var Input $INPUT */
964    global $INPUT;
965
966    $lock = wikiLockFN($id);
967    if(file_exists($lock)) {
968        @list($ip, $session) = explode("\n", io_readFile($lock));
969        if($ip == $INPUT->server->str('REMOTE_USER') || $ip == clientIP() || $session == session_id()) {
970            @unlink($lock);
971            return true;
972        }
973    }
974    return false;
975}
976
977/**
978 * convert line ending to unix format
979 *
980 * also makes sure the given text is valid UTF-8
981 *
982 * @see    formText() for 2crlf conversion
983 * @author Andreas Gohr <andi@splitbrain.org>
984 *
985 * @param string $text
986 * @return string
987 */
988function cleanText($text) {
989    $text = preg_replace("/(\015\012)|(\015)/", "\012", $text);
990
991    // if the text is not valid UTF-8 we simply assume latin1
992    // this won't break any worse than it breaks with the wrong encoding
993    // but might actually fix the problem in many cases
994    if(!utf8_check($text)) $text = utf8_encode($text);
995
996    return $text;
997}
998
999/**
1000 * Prepares text for print in Webforms by encoding special chars.
1001 * It also converts line endings to Windows format which is
1002 * pseudo standard for webforms.
1003 *
1004 * @see    cleanText() for 2unix conversion
1005 * @author Andreas Gohr <andi@splitbrain.org>
1006 *
1007 * @param string $text
1008 * @return string
1009 */
1010function formText($text) {
1011    $text = str_replace("\012", "\015\012", $text);
1012    return htmlspecialchars($text);
1013}
1014
1015/**
1016 * Returns the specified local text in raw format
1017 *
1018 * @author Andreas Gohr <andi@splitbrain.org>
1019 *
1020 * @param string $id   page id
1021 * @param string $ext  extension of file being read, default 'txt'
1022 * @return string
1023 */
1024function rawLocale($id, $ext = 'txt') {
1025    return io_readFile(localeFN($id, $ext));
1026}
1027
1028/**
1029 * Returns the raw WikiText
1030 *
1031 * @author Andreas Gohr <andi@splitbrain.org>
1032 *
1033 * @param string $id   page id
1034 * @param string|int $rev  timestamp when a revision of wikitext is desired
1035 * @return string
1036 */
1037function rawWiki($id, $rev = '') {
1038    return io_readWikiPage(wikiFN($id, $rev), $id, $rev);
1039}
1040
1041/**
1042 * Returns the pagetemplate contents for the ID's namespace
1043 *
1044 * @triggers COMMON_PAGETPL_LOAD
1045 * @author Andreas Gohr <andi@splitbrain.org>
1046 *
1047 * @param string $id the id of the page to be created
1048 * @return string parsed pagetemplate content
1049 */
1050function pageTemplate($id) {
1051    global $conf;
1052
1053    if(is_array($id)) $id = $id[0];
1054
1055    // prepare initial event data
1056    $data = array(
1057        'id'        => $id, // the id of the page to be created
1058        'tpl'       => '', // the text used as template
1059        'tplfile'   => '', // the file above text was/should be loaded from
1060        'doreplace' => true // should wildcard replacements be done on the text?
1061    );
1062
1063    $evt = new Doku_Event('COMMON_PAGETPL_LOAD', $data);
1064    if($evt->advise_before(true)) {
1065        // the before event might have loaded the content already
1066        if(empty($data['tpl'])) {
1067            // if the before event did not set a template file, try to find one
1068            if(empty($data['tplfile'])) {
1069                $path = dirname(wikiFN($id));
1070                if(file_exists($path.'/_template.txt')) {
1071                    $data['tplfile'] = $path.'/_template.txt';
1072                } else {
1073                    // search upper namespaces for templates
1074                    $len = strlen(rtrim($conf['datadir'], '/'));
1075                    while(strlen($path) >= $len) {
1076                        if(file_exists($path.'/__template.txt')) {
1077                            $data['tplfile'] = $path.'/__template.txt';
1078                            break;
1079                        }
1080                        $path = substr($path, 0, strrpos($path, '/'));
1081                    }
1082                }
1083            }
1084            // load the content
1085            $data['tpl'] = io_readFile($data['tplfile']);
1086        }
1087        if($data['doreplace']) parsePageTemplate($data);
1088    }
1089    $evt->advise_after();
1090    unset($evt);
1091
1092    return $data['tpl'];
1093}
1094
1095/**
1096 * Performs common page template replacements
1097 * This works on data from COMMON_PAGETPL_LOAD
1098 *
1099 * @author Andreas Gohr <andi@splitbrain.org>
1100 *
1101 * @param array $data array with event data
1102 * @return string
1103 */
1104function parsePageTemplate(&$data) {
1105    /**
1106     * @var string $id        the id of the page to be created
1107     * @var string $tpl       the text used as template
1108     * @var string $tplfile   the file above text was/should be loaded from
1109     * @var bool   $doreplace should wildcard replacements be done on the text?
1110     */
1111    extract($data);
1112
1113    global $USERINFO;
1114    global $conf;
1115    /* @var Input $INPUT */
1116    global $INPUT;
1117
1118    // replace placeholders
1119    $file = noNS($id);
1120    $page = strtr($file, $conf['sepchar'], ' ');
1121
1122    $tpl = str_replace(
1123        array(
1124             '@ID@',
1125             '@NS@',
1126             '@CURNS@',
1127             '@FILE@',
1128             '@!FILE@',
1129             '@!FILE!@',
1130             '@PAGE@',
1131             '@!PAGE@',
1132             '@!!PAGE@',
1133             '@!PAGE!@',
1134             '@USER@',
1135             '@NAME@',
1136             '@MAIL@',
1137             '@DATE@',
1138        ),
1139        array(
1140             $id,
1141             getNS($id),
1142             curNS($id),
1143             $file,
1144             utf8_ucfirst($file),
1145             utf8_strtoupper($file),
1146             $page,
1147             utf8_ucfirst($page),
1148             utf8_ucwords($page),
1149             utf8_strtoupper($page),
1150             $INPUT->server->str('REMOTE_USER'),
1151             $USERINFO['name'],
1152             $USERINFO['mail'],
1153             $conf['dformat'],
1154        ), $tpl
1155    );
1156
1157    // we need the callback to work around strftime's char limit
1158    $tpl = preg_replace_callback(
1159        '/%./',
1160        function ($m) {
1161            return strftime($m[0]);
1162        },
1163        $tpl
1164    );
1165    $data['tpl'] = $tpl;
1166    return $tpl;
1167}
1168
1169/**
1170 * Returns the raw Wiki Text in three slices.
1171 *
1172 * The range parameter needs to have the form "from-to"
1173 * and gives the range of the section in bytes - no
1174 * UTF-8 awareness is needed.
1175 * The returned order is prefix, section and suffix.
1176 *
1177 * @author Andreas Gohr <andi@splitbrain.org>
1178 *
1179 * @param string $range in form "from-to"
1180 * @param string $id    page id
1181 * @param string $rev   optional, the revision timestamp
1182 * @return string[] with three slices
1183 */
1184function rawWikiSlices($range, $id, $rev = '') {
1185    $text = io_readWikiPage(wikiFN($id, $rev), $id, $rev);
1186
1187    // Parse range
1188    list($from, $to) = explode('-', $range, 2);
1189    // Make range zero-based, use defaults if marker is missing
1190    $from = !$from ? 0 : ($from - 1);
1191    $to   = !$to ? strlen($text) : ($to - 1);
1192
1193    $slices = array();
1194    $slices[0] = substr($text, 0, $from);
1195    $slices[1] = substr($text, $from, $to - $from);
1196    $slices[2] = substr($text, $to);
1197    return $slices;
1198}
1199
1200/**
1201 * Joins wiki text slices
1202 *
1203 * function to join the text slices.
1204 * When the pretty parameter is set to true it adds additional empty
1205 * lines between sections if needed (used on saving).
1206 *
1207 * @author Andreas Gohr <andi@splitbrain.org>
1208 *
1209 * @param string $pre   prefix
1210 * @param string $text  text in the middle
1211 * @param string $suf   suffix
1212 * @param bool $pretty add additional empty lines between sections
1213 * @return string
1214 */
1215function con($pre, $text, $suf, $pretty = false) {
1216    if($pretty) {
1217        if($pre !== '' && substr($pre, -1) !== "\n" &&
1218            substr($text, 0, 1) !== "\n"
1219        ) {
1220            $pre .= "\n";
1221        }
1222        if($suf !== '' && substr($text, -1) !== "\n" &&
1223            substr($suf, 0, 1) !== "\n"
1224        ) {
1225            $text .= "\n";
1226        }
1227    }
1228
1229    return $pre.$text.$suf;
1230}
1231
1232/**
1233 * Checks if the current page version is newer than the last entry in the page's
1234 * changelog. If so, we assume it has been an external edit and we create an
1235 * attic copy and add a proper changelog line.
1236 *
1237 * This check is only executed when the page is about to be saved again from the
1238 * wiki, triggered in @see saveWikiText()
1239 *
1240 * @param string $id the page ID
1241 */
1242function detectExternalEdit($id) {
1243    global $lang;
1244
1245    $fileLastMod = wikiFN($id);
1246    $lastMod     = @filemtime($fileLastMod); // from page
1247    $pagelog     = new PageChangeLog($id, 1024);
1248    $lastRev     = $pagelog->getRevisions(-1, 1); // from changelog
1249    $lastRev     = (int) (empty($lastRev) ? 0 : $lastRev[0]);
1250
1251    if(!file_exists(wikiFN($id, $lastMod)) && file_exists($fileLastMod) && $lastMod >= $lastRev) {
1252        // add old revision to the attic if missing
1253        saveOldRevision($id);
1254        // add a changelog entry if this edit came from outside dokuwiki
1255        if($lastMod > $lastRev) {
1256            $fileLastRev = wikiFN($id, $lastRev);
1257            $revinfo = $pagelog->getRevisionInfo($lastRev);
1258            if(empty($lastRev) || !file_exists($fileLastRev) || $revinfo['type'] == DOKU_CHANGE_TYPE_DELETE) {
1259                $filesize_old = 0;
1260            } else {
1261                $filesize_old = io_getSizeFile($fileLastRev);
1262            }
1263            $filesize_new = filesize($fileLastMod);
1264            $sizechange = $filesize_new - $filesize_old;
1265
1266            addLogEntry($lastMod, $id, DOKU_CHANGE_TYPE_EDIT, $lang['external_edit'], '', array('ExternalEdit'=> true), $sizechange);
1267            // remove soon to be stale instructions
1268            $cache = new cache_instructions($id, $fileLastMod);
1269            $cache->removeCache();
1270        }
1271    }
1272}
1273
1274/**
1275 * Saves a wikitext by calling io_writeWikiPage.
1276 * Also directs changelog and attic updates.
1277 *
1278 * @author Andreas Gohr <andi@splitbrain.org>
1279 * @author Ben Coburn <btcoburn@silicodon.net>
1280 *
1281 * @param string $id       page id
1282 * @param string $text     wikitext being saved
1283 * @param string $summary  summary of text update
1284 * @param bool   $minor    mark this saved version as minor update
1285 */
1286function saveWikiText($id, $text, $summary, $minor = false) {
1287    /* Note to developers:
1288       This code is subtle and delicate. Test the behavior of
1289       the attic and changelog with dokuwiki and external edits
1290       after any changes. External edits change the wiki page
1291       directly without using php or dokuwiki.
1292     */
1293    global $conf;
1294    global $lang;
1295    global $REV;
1296    /* @var Input $INPUT */
1297    global $INPUT;
1298
1299    // prepare data for event
1300    $svdta = array();
1301    $svdta['id']             = $id;
1302    $svdta['file']           = wikiFN($id);
1303    $svdta['revertFrom']     = $REV;
1304    $svdta['oldRevision']    = @filemtime($svdta['file']);
1305    $svdta['newRevision']    = 0;
1306    $svdta['newContent']     = $text;
1307    $svdta['oldContent']     = rawWiki($id);
1308    $svdta['summary']        = $summary;
1309    $svdta['contentChanged'] = ($svdta['newContent'] != $svdta['oldContent']);
1310    $svdta['changeInfo']     = '';
1311    $svdta['changeType']     = DOKU_CHANGE_TYPE_EDIT;
1312    $svdta['sizechange']     = null;
1313
1314    // select changelog line type
1315    if($REV) {
1316        $svdta['changeType']  = DOKU_CHANGE_TYPE_REVERT;
1317        $svdta['changeInfo'] = $REV;
1318    } else if(!file_exists($svdta['file'])) {
1319        $svdta['changeType'] = DOKU_CHANGE_TYPE_CREATE;
1320    } else if(trim($text) == '') {
1321        // empty or whitespace only content deletes
1322        $svdta['changeType'] = DOKU_CHANGE_TYPE_DELETE;
1323        // autoset summary on deletion
1324        if(blank($svdta['summary'])) {
1325            $svdta['summary'] = $lang['deleted'];
1326        }
1327    } else if($minor && $conf['useacl'] && $INPUT->server->str('REMOTE_USER')) {
1328        //minor edits only for logged in users
1329        $svdta['changeType'] = DOKU_CHANGE_TYPE_MINOR_EDIT;
1330    }
1331
1332    $event = new Doku_Event('COMMON_WIKIPAGE_SAVE', $svdta);
1333    if(!$event->advise_before()) return;
1334
1335    // if the content has not been changed, no save happens (plugins may override this)
1336    if(!$svdta['contentChanged']) return;
1337
1338    detectExternalEdit($id);
1339
1340    if(
1341        $svdta['changeType'] == DOKU_CHANGE_TYPE_CREATE ||
1342        ($svdta['changeType'] == DOKU_CHANGE_TYPE_REVERT && !file_exists($svdta['file']))
1343    ) {
1344        $filesize_old = 0;
1345    } else {
1346        $filesize_old = filesize($svdta['file']);
1347    }
1348    if($svdta['changeType'] == DOKU_CHANGE_TYPE_DELETE) {
1349        // Send "update" event with empty data, so plugins can react to page deletion
1350        $data = array(array($svdta['file'], '', false), getNS($id), noNS($id), false);
1351        trigger_event('IO_WIKIPAGE_WRITE', $data);
1352        // pre-save deleted revision
1353        @touch($svdta['file']);
1354        clearstatcache();
1355        $svdta['newRevision'] = saveOldRevision($id);
1356        // remove empty file
1357        @unlink($svdta['file']);
1358        $filesize_new = 0;
1359        // don't remove old meta info as it should be saved, plugins can use IO_WIKIPAGE_WRITE for removing their metadata...
1360        // purge non-persistant meta data
1361        p_purge_metadata($id);
1362        // remove empty namespaces
1363        io_sweepNS($id, 'datadir');
1364        io_sweepNS($id, 'mediadir');
1365    } else {
1366        // save file (namespace dir is created in io_writeWikiPage)
1367        io_writeWikiPage($svdta['file'], $svdta['newContent'], $id);
1368        // pre-save the revision, to keep the attic in sync
1369        $svdta['newRevision'] = saveOldRevision($id);
1370        $filesize_new = filesize($svdta['file']);
1371    }
1372    $svdta['sizechange'] = $filesize_new - $filesize_old;
1373
1374    $event->advise_after();
1375
1376    addLogEntry($svdta['newRevision'], $svdta['id'], $svdta['changeType'], $svdta['summary'], $svdta['changeInfo'], null, $svdta['sizechange']);
1377
1378    // send notify mails
1379    notify($svdta['id'], 'admin', $svdta['oldRevision'], $svdta['summary'], $minor);
1380    notify($svdta['id'], 'subscribers', $svdta['oldRevision'], $svdta['summary'], $minor);
1381
1382    // update the purgefile (timestamp of the last time anything within the wiki was changed)
1383    io_saveFile($conf['cachedir'].'/purgefile', time());
1384
1385    // if useheading is enabled, purge the cache of all linking pages
1386    if(useHeading('content')) {
1387        $pages = ft_backlinks($id, true);
1388        foreach($pages as $page) {
1389            $cache = new cache_renderer($page, wikiFN($page), 'xhtml');
1390            $cache->removeCache();
1391        }
1392    }
1393}
1394
1395/**
1396 * moves the current version to the attic and returns its
1397 * revision date
1398 *
1399 * @author Andreas Gohr <andi@splitbrain.org>
1400 *
1401 * @param string $id page id
1402 * @return int|string revision timestamp
1403 */
1404function saveOldRevision($id) {
1405    $oldf = wikiFN($id);
1406    if(!file_exists($oldf)) return '';
1407    $date = filemtime($oldf);
1408    $newf = wikiFN($id, $date);
1409    io_writeWikiPage($newf, rawWiki($id), $id, $date);
1410    return $date;
1411}
1412
1413/**
1414 * Sends a notify mail on page change or registration
1415 *
1416 * @param string     $id       The changed page
1417 * @param string     $who      Who to notify (admin|subscribers|register)
1418 * @param int|string $rev Old page revision
1419 * @param string     $summary  What changed
1420 * @param boolean    $minor    Is this a minor edit?
1421 * @param string[]   $replace  Additional string substitutions, @KEY@ to be replaced by value
1422 * @return bool
1423 *
1424 * @author Andreas Gohr <andi@splitbrain.org>
1425 */
1426function notify($id, $who, $rev = '', $summary = '', $minor = false, $replace = array()) {
1427    global $conf;
1428    /* @var Input $INPUT */
1429    global $INPUT;
1430
1431    // decide if there is something to do, eg. whom to mail
1432    if($who == 'admin') {
1433        if(empty($conf['notify'])) return false; //notify enabled?
1434        $tpl = 'mailtext';
1435        $to  = $conf['notify'];
1436    } elseif($who == 'subscribers') {
1437        if(!actionOK('subscribe')) return false; //subscribers enabled?
1438        if($conf['useacl'] && $INPUT->server->str('REMOTE_USER') && $minor) return false; //skip minors
1439        $data = array('id' => $id, 'addresslist' => '', 'self' => false, 'replacements' => $replace);
1440        trigger_event(
1441            'COMMON_NOTIFY_ADDRESSLIST', $data,
1442            array(new Subscription(), 'notifyaddresses')
1443        );
1444        $to = $data['addresslist'];
1445        if(empty($to)) return false;
1446        $tpl = 'subscr_single';
1447    } else {
1448        return false; //just to be safe
1449    }
1450
1451    // prepare content
1452    $subscription = new Subscription();
1453    return $subscription->send_diff($to, $tpl, $id, $rev, $summary);
1454}
1455
1456/**
1457 * extracts the query from a search engine referrer
1458 *
1459 * @author Andreas Gohr <andi@splitbrain.org>
1460 * @author Todd Augsburger <todd@rollerorgans.com>
1461 *
1462 * @return array|string
1463 */
1464function getGoogleQuery() {
1465    /* @var Input $INPUT */
1466    global $INPUT;
1467
1468    if(!$INPUT->server->has('HTTP_REFERER')) {
1469        return '';
1470    }
1471    $url = parse_url($INPUT->server->str('HTTP_REFERER'));
1472
1473    // only handle common SEs
1474    if(!preg_match('/(google|bing|yahoo|ask|duckduckgo|babylon|aol|yandex)/',$url['host'])) return '';
1475
1476    $query = array();
1477    // temporary workaround against PHP bug #49733
1478    // see http://bugs.php.net/bug.php?id=49733
1479    if(UTF8_MBSTRING) $enc = mb_internal_encoding();
1480    parse_str($url['query'], $query);
1481    if(UTF8_MBSTRING) mb_internal_encoding($enc);
1482
1483    $q = '';
1484    if(isset($query['q'])){
1485        $q = $query['q'];
1486    }elseif(isset($query['p'])){
1487        $q = $query['p'];
1488    }elseif(isset($query['query'])){
1489        $q = $query['query'];
1490    }
1491    $q = trim($q);
1492
1493    if(!$q) return '';
1494    $q = preg_split('/[\s\'"\\\\`()\]\[?:!\.{};,#+*<>\\/]+/', $q, -1, PREG_SPLIT_NO_EMPTY);
1495    return $q;
1496}
1497
1498/**
1499 * Return the human readable size of a file
1500 *
1501 * @param int $size A file size
1502 * @param int $dec A number of decimal places
1503 * @return string human readable size
1504 *
1505 * @author      Martin Benjamin <b.martin@cybernet.ch>
1506 * @author      Aidan Lister <aidan@php.net>
1507 * @version     1.0.0
1508 */
1509function filesize_h($size, $dec = 1) {
1510    $sizes = array('B', 'KB', 'MB', 'GB');
1511    $count = count($sizes);
1512    $i     = 0;
1513
1514    while($size >= 1024 && ($i < $count - 1)) {
1515        $size /= 1024;
1516        $i++;
1517    }
1518
1519    return round($size, $dec)."\xC2\xA0".$sizes[$i]; //non-breaking space
1520}
1521
1522/**
1523 * Return the given timestamp as human readable, fuzzy age
1524 *
1525 * @author Andreas Gohr <gohr@cosmocode.de>
1526 *
1527 * @param int $dt timestamp
1528 * @return string
1529 */
1530function datetime_h($dt) {
1531    global $lang;
1532
1533    $ago = time() - $dt;
1534    if($ago > 24 * 60 * 60 * 30 * 12 * 2) {
1535        return sprintf($lang['years'], round($ago / (24 * 60 * 60 * 30 * 12)));
1536    }
1537    if($ago > 24 * 60 * 60 * 30 * 2) {
1538        return sprintf($lang['months'], round($ago / (24 * 60 * 60 * 30)));
1539    }
1540    if($ago > 24 * 60 * 60 * 7 * 2) {
1541        return sprintf($lang['weeks'], round($ago / (24 * 60 * 60 * 7)));
1542    }
1543    if($ago > 24 * 60 * 60 * 2) {
1544        return sprintf($lang['days'], round($ago / (24 * 60 * 60)));
1545    }
1546    if($ago > 60 * 60 * 2) {
1547        return sprintf($lang['hours'], round($ago / (60 * 60)));
1548    }
1549    if($ago > 60 * 2) {
1550        return sprintf($lang['minutes'], round($ago / (60)));
1551    }
1552    return sprintf($lang['seconds'], $ago);
1553}
1554
1555/**
1556 * Wraps around strftime but provides support for fuzzy dates
1557 *
1558 * The format default to $conf['dformat']. It is passed to
1559 * strftime - %f can be used to get the value from datetime_h()
1560 *
1561 * @see datetime_h
1562 * @author Andreas Gohr <gohr@cosmocode.de>
1563 *
1564 * @param int|null $dt      timestamp when given, null will take current timestamp
1565 * @param string   $format  empty default to $conf['dformat'], or provide format as recognized by strftime()
1566 * @return string
1567 */
1568function dformat($dt = null, $format = '') {
1569    global $conf;
1570
1571    if(is_null($dt)) $dt = time();
1572    $dt = (int) $dt;
1573    if(!$format) $format = $conf['dformat'];
1574
1575    $format = str_replace('%f', datetime_h($dt), $format);
1576    return strftime($format, $dt);
1577}
1578
1579/**
1580 * Formats a timestamp as ISO 8601 date
1581 *
1582 * @author <ungu at terong dot com>
1583 * @link http://php.net/manual/en/function.date.php#54072
1584 *
1585 * @param int $int_date current date in UNIX timestamp
1586 * @return string
1587 */
1588function date_iso8601($int_date) {
1589    $date_mod     = date('Y-m-d\TH:i:s', $int_date);
1590    $pre_timezone = date('O', $int_date);
1591    $time_zone    = substr($pre_timezone, 0, 3).":".substr($pre_timezone, 3, 2);
1592    $date_mod .= $time_zone;
1593    return $date_mod;
1594}
1595
1596/**
1597 * return an obfuscated email address in line with $conf['mailguard'] setting
1598 *
1599 * @author Harry Fuecks <hfuecks@gmail.com>
1600 * @author Christopher Smith <chris@jalakai.co.uk>
1601 *
1602 * @param string $email email address
1603 * @return string
1604 */
1605function obfuscate($email) {
1606    global $conf;
1607
1608    switch($conf['mailguard']) {
1609        case 'visible' :
1610            $obfuscate = array('@' => ' [at] ', '.' => ' [dot] ', '-' => ' [dash] ');
1611            return strtr($email, $obfuscate);
1612
1613        case 'hex' :
1614            $encode = '';
1615            $len    = strlen($email);
1616            for($x = 0; $x < $len; $x++) {
1617                $encode .= '&#x'.bin2hex($email{$x}).';';
1618            }
1619            return $encode;
1620
1621        case 'none' :
1622        default :
1623            return $email;
1624    }
1625}
1626
1627/**
1628 * Removes quoting backslashes
1629 *
1630 * @author Andreas Gohr <andi@splitbrain.org>
1631 *
1632 * @param string $string
1633 * @param string $char backslashed character
1634 * @return string
1635 */
1636function unslash($string, $char = "'") {
1637    return str_replace('\\'.$char, $char, $string);
1638}
1639
1640/**
1641 * Convert php.ini shorthands to byte
1642 *
1643 * On 32 bit systems values >= 2GB will fail!
1644 *
1645 * -1 (infinite size) will be reported as -1
1646 *
1647 * @link   https://www.php.net/manual/en/faq.using.php#faq.using.shorthandbytes
1648 * @param string $value PHP size shorthand
1649 * @return int
1650 */
1651function php_to_byte($value) {
1652    switch (strtoupper($value[-1])) {
1653        case 'G':
1654            $ret = intval(substr($value, 0, -1)) * 1024 * 1024 * 1024;
1655            break;
1656        case 'M':
1657            $ret = intval(substr($value, 0, -1)) * 1024 * 1024;
1658            break;
1659        case 'K':
1660            $ret = intval(substr($value, 0, -1)) * 1024;
1661            break;
1662        default;
1663            $ret = intval($value);
1664            break;
1665    }
1666    return $ret;
1667}
1668
1669/**
1670 * Wrapper around preg_quote adding the default delimiter
1671 *
1672 * @param string $string
1673 * @return string
1674 */
1675function preg_quote_cb($string) {
1676    return preg_quote($string, '/');
1677}
1678
1679/**
1680 * Shorten a given string by removing data from the middle
1681 *
1682 * You can give the string in two parts, the first part $keep
1683 * will never be shortened. The second part $short will be cut
1684 * in the middle to shorten but only if at least $min chars are
1685 * left to display it. Otherwise it will be left off.
1686 *
1687 * @param string $keep   the part to keep
1688 * @param string $short  the part to shorten
1689 * @param int    $max    maximum chars you want for the whole string
1690 * @param int    $min    minimum number of chars to have left for middle shortening
1691 * @param string $char   the shortening character to use
1692 * @return string
1693 */
1694function shorten($keep, $short, $max, $min = 9, $char = '…') {
1695    $max = $max - utf8_strlen($keep);
1696    if($max < $min) return $keep;
1697    $len = utf8_strlen($short);
1698    if($len <= $max) return $keep.$short;
1699    $half = floor($max / 2);
1700    return $keep.utf8_substr($short, 0, $half - 1).$char.utf8_substr($short, $len - $half);
1701}
1702
1703/**
1704 * Return the users real name or e-mail address for use
1705 * in page footer and recent changes pages
1706 *
1707 * @param string|null $username or null when currently logged-in user should be used
1708 * @param bool $textonly true returns only plain text, true allows returning html
1709 * @return string html or plain text(not escaped) of formatted user name
1710 *
1711 * @author Andy Webber <dokuwiki AT andywebber DOT com>
1712 */
1713function editorinfo($username, $textonly = false) {
1714    return userlink($username, $textonly);
1715}
1716
1717/**
1718 * Returns users realname w/o link
1719 *
1720 * @param string|null $username or null when currently logged-in user should be used
1721 * @param bool $textonly true returns only plain text, true allows returning html
1722 * @return string html or plain text(not escaped) of formatted user name
1723 *
1724 * @triggers COMMON_USER_LINK
1725 */
1726function userlink($username = null, $textonly = false) {
1727    global $conf, $INFO;
1728    /** @var DokuWiki_Auth_Plugin $auth */
1729    global $auth;
1730    /** @var Input $INPUT */
1731    global $INPUT;
1732
1733    // prepare initial event data
1734    $data = array(
1735        'username' => $username, // the unique user name
1736        'name' => '',
1737        'link' => array( //setting 'link' to false disables linking
1738                         'target' => '',
1739                         'pre' => '',
1740                         'suf' => '',
1741                         'style' => '',
1742                         'more' => '',
1743                         'url' => '',
1744                         'title' => '',
1745                         'class' => ''
1746        ),
1747        'userlink' => '', // formatted user name as will be returned
1748        'textonly' => $textonly
1749    );
1750    if($username === null) {
1751        $data['username'] = $username = $INPUT->server->str('REMOTE_USER');
1752        if($textonly){
1753            $data['name'] = $INFO['userinfo']['name']. ' (' . $INPUT->server->str('REMOTE_USER') . ')';
1754        }else {
1755            $data['name'] = '<bdi>' . hsc($INFO['userinfo']['name']) . '</bdi> (<bdi>' . hsc($INPUT->server->str('REMOTE_USER')) . '</bdi>)';
1756        }
1757    }
1758
1759    $evt = new Doku_Event('COMMON_USER_LINK', $data);
1760    if($evt->advise_before(true)) {
1761        if(empty($data['name'])) {
1762            if($auth) $info = $auth->getUserData($username);
1763            if($conf['showuseras'] != 'loginname' && isset($info) && $info) {
1764                switch($conf['showuseras']) {
1765                    case 'username':
1766                    case 'username_link':
1767                        $data['name'] = $textonly ? $info['name'] : hsc($info['name']);
1768                        break;
1769                    case 'email':
1770                    case 'email_link':
1771                        $data['name'] = obfuscate($info['mail']);
1772                        break;
1773                }
1774            } else {
1775                $data['name'] = $textonly ? $data['username'] : hsc($data['username']);
1776            }
1777        }
1778
1779        /** @var Doku_Renderer_xhtml $xhtml_renderer */
1780        static $xhtml_renderer = null;
1781
1782        if(!$data['textonly'] && empty($data['link']['url'])) {
1783
1784            if(in_array($conf['showuseras'], array('email_link', 'username_link'))) {
1785                if(!isset($info)) {
1786                    if($auth) $info = $auth->getUserData($username);
1787                }
1788                if(isset($info) && $info) {
1789                    if($conf['showuseras'] == 'email_link') {
1790                        $data['link']['url'] = 'mailto:' . obfuscate($info['mail']);
1791                    } else {
1792                        if(is_null($xhtml_renderer)) {
1793                            $xhtml_renderer = p_get_renderer('xhtml');
1794                        }
1795                        if(empty($xhtml_renderer->interwiki)) {
1796                            $xhtml_renderer->interwiki = getInterwiki();
1797                        }
1798                        $shortcut = 'user';
1799                        $exists = null;
1800                        $data['link']['url'] = $xhtml_renderer->_resolveInterWiki($shortcut, $username, $exists);
1801                        $data['link']['class'] .= ' interwiki iw_user';
1802                        if($exists !== null) {
1803                            if($exists) {
1804                                $data['link']['class'] .= ' wikilink1';
1805                            } else {
1806                                $data['link']['class'] .= ' wikilink2';
1807                                $data['link']['rel'] = 'nofollow';
1808                            }
1809                        }
1810                    }
1811                } else {
1812                    $data['textonly'] = true;
1813                }
1814
1815            } else {
1816                $data['textonly'] = true;
1817            }
1818        }
1819
1820        if($data['textonly']) {
1821            $data['userlink'] = $data['name'];
1822        } else {
1823            $data['link']['name'] = $data['name'];
1824            if(is_null($xhtml_renderer)) {
1825                $xhtml_renderer = p_get_renderer('xhtml');
1826            }
1827            $data['userlink'] = $xhtml_renderer->_formatLink($data['link']);
1828        }
1829    }
1830    $evt->advise_after();
1831    unset($evt);
1832
1833    return $data['userlink'];
1834}
1835
1836/**
1837 * Returns the path to a image file for the currently chosen license.
1838 * When no image exists, returns an empty string
1839 *
1840 * @author Andreas Gohr <andi@splitbrain.org>
1841 *
1842 * @param  string $type - type of image 'badge' or 'button'
1843 * @return string
1844 */
1845function license_img($type) {
1846    global $license;
1847    global $conf;
1848    if(!$conf['license']) return '';
1849    if(!is_array($license[$conf['license']])) return '';
1850    $try   = array();
1851    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.png';
1852    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.gif';
1853    if(substr($conf['license'], 0, 3) == 'cc-') {
1854        $try[] = 'lib/images/license/'.$type.'/cc.png';
1855    }
1856    foreach($try as $src) {
1857        if(file_exists(DOKU_INC.$src)) return $src;
1858    }
1859    return '';
1860}
1861
1862/**
1863 * Checks if the given amount of memory is available
1864 *
1865 * If the memory_get_usage() function is not available the
1866 * function just assumes $bytes of already allocated memory
1867 *
1868 * @author Filip Oscadal <webmaster@illusionsoftworks.cz>
1869 * @author Andreas Gohr <andi@splitbrain.org>
1870 *
1871 * @param int  $mem    Size of memory you want to allocate in bytes
1872 * @param int  $bytes  already allocated memory (see above)
1873 * @return bool
1874 */
1875function is_mem_available($mem, $bytes = 1048576) {
1876    $limit = trim(ini_get('memory_limit'));
1877    if(empty($limit)) return true; // no limit set!
1878    if($limit == -1) return true; // unlimited
1879
1880    // parse limit to bytes
1881    $limit = php_to_byte($limit);
1882
1883    // get used memory if possible
1884    if(function_exists('memory_get_usage')) {
1885        $used = memory_get_usage();
1886    } else {
1887        $used = $bytes;
1888    }
1889
1890    if($used + $mem > $limit) {
1891        return false;
1892    }
1893
1894    return true;
1895}
1896
1897/**
1898 * Send a HTTP redirect to the browser
1899 *
1900 * Works arround Microsoft IIS cookie sending bug. Exits the script.
1901 *
1902 * @link   http://support.microsoft.com/kb/q176113/
1903 * @author Andreas Gohr <andi@splitbrain.org>
1904 *
1905 * @param string $url url being directed to
1906 */
1907function send_redirect($url) {
1908    $url = stripctl($url); // defend against HTTP Response Splitting
1909
1910    /* @var Input $INPUT */
1911    global $INPUT;
1912
1913    //are there any undisplayed messages? keep them in session for display
1914    global $MSG;
1915    if(isset($MSG) && count($MSG) && !defined('NOSESSION')) {
1916        //reopen session, store data and close session again
1917        @session_start();
1918        $_SESSION[DOKU_COOKIE]['msg'] = $MSG;
1919    }
1920
1921    // always close the session
1922    session_write_close();
1923
1924    // check if running on IIS < 6 with CGI-PHP
1925    if($INPUT->server->has('SERVER_SOFTWARE') && $INPUT->server->has('GATEWAY_INTERFACE') &&
1926        (strpos($INPUT->server->str('GATEWAY_INTERFACE'), 'CGI') !== false) &&
1927        (preg_match('|^Microsoft-IIS/(\d)\.\d$|', trim($INPUT->server->str('SERVER_SOFTWARE')), $matches)) &&
1928        $matches[1] < 6
1929    ) {
1930        header('Refresh: 0;url='.$url);
1931    } else {
1932        header('Location: '.$url);
1933    }
1934
1935    // no exits during unit tests
1936    if(defined('DOKU_UNITTEST')) {
1937        // pass info about the redirect back to the test suite
1938        $testRequest = TestRequest::getRunning();
1939        if($testRequest !== null) {
1940            $testRequest->addData('send_redirect', $url);
1941        }
1942        return;
1943    }
1944
1945    exit;
1946}
1947
1948/**
1949 * Validate a value using a set of valid values
1950 *
1951 * This function checks whether a specified value is set and in the array
1952 * $valid_values. If not, the function returns a default value or, if no
1953 * default is specified, throws an exception.
1954 *
1955 * @param string $param        The name of the parameter
1956 * @param array  $valid_values A set of valid values; Optionally a default may
1957 *                             be marked by the key “default”.
1958 * @param array  $array        The array containing the value (typically $_POST
1959 *                             or $_GET)
1960 * @param string $exc          The text of the raised exception
1961 *
1962 * @throws Exception
1963 * @return mixed
1964 * @author Adrian Lang <lang@cosmocode.de>
1965 */
1966function valid_input_set($param, $valid_values, $array, $exc = '') {
1967    if(isset($array[$param]) && in_array($array[$param], $valid_values)) {
1968        return $array[$param];
1969    } elseif(isset($valid_values['default'])) {
1970        return $valid_values['default'];
1971    } else {
1972        throw new Exception($exc);
1973    }
1974}
1975
1976/**
1977 * Read a preference from the DokuWiki cookie
1978 * (remembering both keys & values are urlencoded)
1979 *
1980 * @param string $pref     preference key
1981 * @param mixed  $default  value returned when preference not found
1982 * @return string preference value
1983 */
1984function get_doku_pref($pref, $default) {
1985    $enc_pref = urlencode($pref);
1986    if(isset($_COOKIE['DOKU_PREFS']) && strpos($_COOKIE['DOKU_PREFS'], $enc_pref) !== false) {
1987        $parts = explode('#', $_COOKIE['DOKU_PREFS']);
1988        $cnt   = count($parts);
1989
1990        // due to #2721 there might be duplicate entries,
1991        // so we read from the end
1992        for($i = $cnt-2; $i >= 0; $i -= 2) {
1993            if($parts[$i] == $enc_pref) {
1994                return urldecode($parts[$i + 1]);
1995            }
1996        }
1997    }
1998    return $default;
1999}
2000
2001/**
2002 * Add a preference to the DokuWiki cookie
2003 * (remembering $_COOKIE['DOKU_PREFS'] is urlencoded)
2004 * Remove it by setting $val to false
2005 *
2006 * @param string $pref  preference key
2007 * @param string $val   preference value
2008 */
2009function set_doku_pref($pref, $val) {
2010    global $conf;
2011    $orig = get_doku_pref($pref, false);
2012    $cookieVal = '';
2013
2014    if($orig !== false && ($orig !== $val)) {
2015        $parts = explode('#', $_COOKIE['DOKU_PREFS']);
2016        $cnt   = count($parts);
2017        // urlencode $pref for the comparison
2018        $enc_pref = rawurlencode($pref);
2019        $seen = false;
2020        for ($i = 0; $i < $cnt; $i += 2) {
2021            if ($parts[$i] == $enc_pref) {
2022                if (!$seen){
2023                    if ($val !== false) {
2024                        $parts[$i + 1] = rawurlencode($val);
2025                    } else {
2026                        unset($parts[$i]);
2027                        unset($parts[$i + 1]);
2028                    }
2029                    $seen = true;
2030                } else {
2031                    // no break because we want to remove duplicate entries
2032                    unset($parts[$i]);
2033                    unset($parts[$i + 1]);
2034                }
2035            }
2036        }
2037        $cookieVal = implode('#', $parts);
2038    } else if ($orig === false && $val !== false) {
2039        $cookieVal = ($_COOKIE['DOKU_PREFS'] ? $_COOKIE['DOKU_PREFS'].'#' : '').rawurlencode($pref).'#'.rawurlencode($val);
2040    }
2041
2042    $cookieDir = empty($conf['cookiedir']) ? DOKU_REL : $conf['cookiedir'];
2043    if(defined('DOKU_UNITTEST')) {
2044        $_COOKIE['DOKU_PREFS'] = $cookieVal;
2045    }else{
2046        setcookie('DOKU_PREFS', $cookieVal, time()+365*24*3600, $cookieDir, '', ($conf['securecookie'] && is_ssl()));
2047    }
2048}
2049
2050/**
2051 * Strips source mapping declarations from given text #601
2052 *
2053 * @param string &$text reference to the CSS or JavaScript code to clean
2054 */
2055function stripsourcemaps(&$text){
2056    $text = preg_replace('/^(\/\/|\/\*)[@#]\s+sourceMappingURL=.*?(\*\/)?$/im', '\\1\\2', $text);
2057}
2058
2059/**
2060 * Returns the contents of a given SVG file for embedding
2061 *
2062 * Inlining SVGs saves on HTTP requests and more importantly allows for styling them through
2063 * CSS. However it should used with small SVGs only. The $maxsize setting ensures only small
2064 * files are embedded.
2065 *
2066 * This strips unneeded headers, comments and newline. The result is not a vaild standalone SVG!
2067 *
2068 * @param string $file full path to the SVG file
2069 * @param int $maxsize maximum allowed size for the SVG to be embedded
2070 * @return string|false the SVG content, false if the file couldn't be loaded
2071 */
2072function inlineSVG($file, $maxsize = 2048) {
2073    $file = trim($file);
2074    if($file === '') return false;
2075    if(!file_exists($file)) return false;
2076    if(filesize($file) > $maxsize) return false;
2077    if(!is_readable($file)) return false;
2078    $content = file_get_contents($file);
2079    $content = preg_replace('/<!--.*?(-->)/s','', $content); // comments
2080    $content = preg_replace('/<\?xml .*?\?>/i', '', $content); // xml header
2081    $content = preg_replace('/<!DOCTYPE .*?>/i', '', $content); // doc type
2082    $content = preg_replace('/>\s+</s', '><', $content); // newlines between tags
2083    $content = trim($content);
2084    if(substr($content, 0, 5) !== '<svg ') return false;
2085    return $content;
2086}
2087
2088//Setup VIM: ex: et ts=2 :
2089