xref: /dokuwiki/inc/common.php (revision 5a932e77b3c806514203323540cb30e5ab9c28cf)
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.');
10require_once(DOKU_INC.'inc/io.php');
11require_once(DOKU_INC.'inc/changelog.php');
12require_once(DOKU_INC.'inc/utf8.php');
13require_once(DOKU_INC.'inc/mail.php');
14require_once(DOKU_INC.'inc/parserutils.php');
15require_once(DOKU_INC.'inc/infoutils.php');
16require_once DOKU_INC.'inc/subscription.php';
17
18/**
19 * These constants are used with the recents function
20 */
21define('RECENTS_SKIP_DELETED',2);
22define('RECENTS_SKIP_MINORS',4);
23define('RECENTS_SKIP_SUBSPACES',8);
24define('RECENTS_MEDIA_CHANGES',16);
25
26/**
27 * Wrapper around htmlspecialchars()
28 *
29 * @author Andreas Gohr <andi@splitbrain.org>
30 * @see    htmlspecialchars()
31 */
32function hsc($string){
33    return htmlspecialchars($string, ENT_QUOTES, 'UTF-8');
34}
35
36/**
37 * print a newline terminated string
38 *
39 * You can give an indention as optional parameter
40 *
41 * @author Andreas Gohr <andi@splitbrain.org>
42 */
43function ptln($string,$indent=0){
44    echo str_repeat(' ', $indent)."$string\n";
45}
46
47/**
48 * strips control characters (<32) from the given string
49 *
50 * @author Andreas Gohr <andi@splitbrain.org>
51 */
52function stripctl($string){
53    return preg_replace('/[\x00-\x1F]+/s','',$string);
54}
55
56/**
57 * Return a secret token to be used for CSRF attack prevention
58 *
59 * @author  Andreas Gohr <andi@splitbrain.org>
60 * @link    http://en.wikipedia.org/wiki/Cross-site_request_forgery
61 * @link    http://christ1an.blogspot.com/2007/04/preventing-csrf-efficiently.html
62 * @return  string
63 */
64function getSecurityToken(){
65    return md5(auth_cookiesalt().session_id());
66}
67
68/**
69 * Check the secret CSRF token
70 */
71function checkSecurityToken($token=null){
72    if(!$_SERVER['REMOTE_USER']) return true; // no logged in user, no need for a check
73
74    if(is_null($token)) $token = $_REQUEST['sectok'];
75    if(getSecurityToken() != $token){
76        msg('Security Token did not match. Possible CSRF attack.',-1);
77        return false;
78    }
79    return true;
80}
81
82/**
83 * Print a hidden form field with a secret CSRF token
84 *
85 * @author  Andreas Gohr <andi@splitbrain.org>
86 */
87function formSecurityToken($print=true){
88    $ret = '<div class="no"><input type="hidden" name="sectok" value="'.getSecurityToken().'" /></div>'."\n";
89    if($print){
90        echo $ret;
91    }else{
92        return $ret;
93    }
94}
95
96/**
97 * Return info about the current document as associative
98 * array.
99 *
100 * @author Andreas Gohr <andi@splitbrain.org>
101 */
102function pageinfo(){
103    global $ID;
104    global $REV;
105    global $RANGE;
106    global $USERINFO;
107    global $conf;
108    global $lang;
109
110    // include ID & REV not redundant, as some parts of DokuWiki may temporarily change $ID, e.g. p_wiki_xhtml
111    // FIXME ... perhaps it would be better to ensure the temporary changes weren't necessary
112    $info['id'] = $ID;
113    $info['rev'] = $REV;
114
115    // set info about manager/admin status.
116    $info['isadmin']   = false;
117    $info['ismanager'] = false;
118    if(isset($_SERVER['REMOTE_USER'])){
119        $info['userinfo']     = $USERINFO;
120        $info['perm']         = auth_quickaclcheck($ID);
121        $info['subscribed']   = get_info_subscribed();
122        $info['client']       = $_SERVER['REMOTE_USER'];
123
124        if($info['perm'] == AUTH_ADMIN){
125            $info['isadmin']   = true;
126            $info['ismanager'] = true;
127        }elseif(auth_ismanager()){
128            $info['ismanager'] = true;
129        }
130
131        // if some outside auth were used only REMOTE_USER is set
132        if(!$info['userinfo']['name']){
133            $info['userinfo']['name'] = $_SERVER['REMOTE_USER'];
134        }
135
136    }else{
137        $info['perm']       = auth_aclcheck($ID,'',null);
138        $info['subscribed'] = false;
139        $info['client']     = clientIP(true);
140    }
141
142    $info['namespace'] = getNS($ID);
143    $info['locked']    = checklock($ID);
144    $info['filepath']  = fullpath(wikiFN($ID));
145    $info['exists']    = @file_exists($info['filepath']);
146    if($REV){
147        //check if current revision was meant
148        if($info['exists'] && (@filemtime($info['filepath'])==$REV)){
149            $REV = '';
150        }elseif($RANGE){
151            //section editing does not work with old revisions!
152            $REV   = '';
153            $RANGE = '';
154            msg($lang['nosecedit'],0);
155        }else{
156            //really use old revision
157            $info['filepath'] = fullpath(wikiFN($ID,$REV));
158            $info['exists']   = @file_exists($info['filepath']);
159        }
160    }
161    $info['rev'] = $REV;
162    if($info['exists']){
163        $info['writable'] = (is_writable($info['filepath']) &&
164                ($info['perm'] >= AUTH_EDIT));
165    }else{
166        $info['writable'] = ($info['perm'] >= AUTH_CREATE);
167    }
168    $info['editable']  = ($info['writable'] && empty($info['lock']));
169    $info['lastmod']   = @filemtime($info['filepath']);
170
171    //load page meta data
172    $info['meta'] = p_get_metadata($ID);
173
174    //who's the editor
175    if($REV){
176        $revinfo = getRevisionInfo($ID, $REV, 1024);
177    }else{
178        if (is_array($info['meta']['last_change'])) {
179            $revinfo = $info['meta']['last_change'];
180        } else {
181            $revinfo = getRevisionInfo($ID, $info['lastmod'], 1024);
182            // cache most recent changelog line in metadata if missing and still valid
183            if ($revinfo!==false) {
184                $info['meta']['last_change'] = $revinfo;
185                p_set_metadata($ID, array('last_change' => $revinfo));
186            }
187        }
188    }
189    //and check for an external edit
190    if($revinfo!==false && $revinfo['date']!=$info['lastmod']){
191        // cached changelog line no longer valid
192        $revinfo = false;
193        $info['meta']['last_change'] = $revinfo;
194        p_set_metadata($ID, array('last_change' => $revinfo));
195    }
196
197    $info['ip']     = $revinfo['ip'];
198    $info['user']   = $revinfo['user'];
199    $info['sum']    = $revinfo['sum'];
200    // See also $INFO['meta']['last_change'] which is the most recent log line for page $ID.
201    // Use $INFO['meta']['last_change']['type']===DOKU_CHANGE_TYPE_MINOR_EDIT in place of $info['minor'].
202
203    if($revinfo['user']){
204        $info['editor'] = $revinfo['user'];
205    }else{
206        $info['editor'] = $revinfo['ip'];
207    }
208
209    // draft
210    $draft = getCacheName($info['client'].$ID,'.draft');
211    if(@file_exists($draft)){
212        if(@filemtime($draft) < @filemtime(wikiFN($ID))){
213            // remove stale draft
214            @unlink($draft);
215        }else{
216            $info['draft'] = $draft;
217        }
218    }
219
220    // mobile detection
221    $info['ismobile'] = clientismobile();
222
223    return $info;
224}
225
226/**
227 * Build an string of URL parameters
228 *
229 * @author Andreas Gohr
230 */
231function buildURLparams($params, $sep='&amp;'){
232    $url = '';
233    $amp = false;
234    foreach($params as $key => $val){
235        if($amp) $url .= $sep;
236
237        $url .= $key.'=';
238        $url .= rawurlencode((string)$val);
239        $amp = true;
240    }
241    return $url;
242}
243
244/**
245 * Build an string of html tag attributes
246 *
247 * Skips keys starting with '_', values get HTML encoded
248 *
249 * @author Andreas Gohr
250 */
251function buildAttributes($params,$skipempty=false){
252    $url = '';
253    foreach($params as $key => $val){
254        if($key{0} == '_') continue;
255        if($val === '' && $skipempty) continue;
256
257        $url .= $key.'="';
258        $url .= htmlspecialchars ($val);
259        $url .= '" ';
260    }
261    return $url;
262}
263
264
265/**
266 * This builds the breadcrumb trail and returns it as array
267 *
268 * @author Andreas Gohr <andi@splitbrain.org>
269 */
270function breadcrumbs(){
271    // we prepare the breadcrumbs early for quick session closing
272    static $crumbs = null;
273    if($crumbs != null) return $crumbs;
274
275    global $ID;
276    global $ACT;
277    global $conf;
278
279    //first visit?
280    $crumbs = isset($_SESSION[DOKU_COOKIE]['bc']) ? $_SESSION[DOKU_COOKIE]['bc'] : array();
281    //we only save on show and existing wiki documents
282    $file = wikiFN($ID);
283    if($ACT != 'show' || !@file_exists($file)){
284        $_SESSION[DOKU_COOKIE]['bc'] = $crumbs;
285        return $crumbs;
286    }
287
288    // page names
289    $name = noNSorNS($ID);
290    if (useHeading('navigation')) {
291        // get page title
292        $title = p_get_first_heading($ID,true);
293        if ($title) {
294            $name = $title;
295        }
296    }
297
298    //remove ID from array
299    if (isset($crumbs[$ID])) {
300        unset($crumbs[$ID]);
301    }
302
303    //add to array
304    $crumbs[$ID] = $name;
305    //reduce size
306    while(count($crumbs) > $conf['breadcrumbs']){
307        array_shift($crumbs);
308    }
309    //save to session
310    $_SESSION[DOKU_COOKIE]['bc'] = $crumbs;
311    return $crumbs;
312}
313
314/**
315 * Filter for page IDs
316 *
317 * This is run on a ID before it is outputted somewhere
318 * currently used to replace the colon with something else
319 * on Windows systems and to have proper URL encoding
320 *
321 * Urlencoding is ommitted when the second parameter is false
322 *
323 * @author Andreas Gohr <andi@splitbrain.org>
324 */
325function idfilter($id,$ue=true){
326    global $conf;
327    if ($conf['useslash'] && $conf['userewrite']){
328        $id = strtr($id,':','/');
329    }elseif (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN' &&
330            $conf['userewrite']) {
331        $id = strtr($id,':',';');
332    }
333    if($ue){
334        $id = rawurlencode($id);
335        $id = str_replace('%3A',':',$id); //keep as colon
336        $id = str_replace('%2F','/',$id); //keep as slash
337    }
338    return $id;
339}
340
341/**
342 * This builds a link to a wikipage
343 *
344 * It handles URL rewriting and adds additional parameter if
345 * given in $more
346 *
347 * @author Andreas Gohr <andi@splitbrain.org>
348 */
349function wl($id='',$more='',$abs=false,$sep='&amp;'){
350    global $conf;
351    if(is_array($more)){
352        $more = buildURLparams($more,$sep);
353    }else{
354        $more = str_replace(',',$sep,$more);
355    }
356
357    $id    = idfilter($id);
358    if($abs){
359        $xlink = DOKU_URL;
360    }else{
361        $xlink = DOKU_BASE;
362    }
363
364    if($conf['userewrite'] == 2){
365        $xlink .= DOKU_SCRIPT.'/'.$id;
366        if($more) $xlink .= '?'.$more;
367    }elseif($conf['userewrite']){
368        $xlink .= $id;
369        if($more) $xlink .= '?'.$more;
370    }elseif($id){
371        $xlink .= DOKU_SCRIPT.'?id='.$id;
372        if($more) $xlink .= $sep.$more;
373    }else{
374        $xlink .= DOKU_SCRIPT;
375        if($more) $xlink .= '?'.$more;
376    }
377
378    return $xlink;
379}
380
381/**
382 * This builds a link to an alternate page format
383 *
384 * Handles URL rewriting if enabled. Follows the style of wl().
385 *
386 * @author Ben Coburn <btcoburn@silicodon.net>
387 */
388function exportlink($id='',$format='raw',$more='',$abs=false,$sep='&amp;'){
389    global $conf;
390    if(is_array($more)){
391        $more = buildURLparams($more,$sep);
392    }else{
393        $more = str_replace(',',$sep,$more);
394    }
395
396    $format = rawurlencode($format);
397    $id = idfilter($id);
398    if($abs){
399        $xlink = DOKU_URL;
400    }else{
401        $xlink = DOKU_BASE;
402    }
403
404    if($conf['userewrite'] == 2){
405        $xlink .= DOKU_SCRIPT.'/'.$id.'?do=export_'.$format;
406        if($more) $xlink .= $sep.$more;
407    }elseif($conf['userewrite'] == 1){
408        $xlink .= '_export/'.$format.'/'.$id;
409        if($more) $xlink .= '?'.$more;
410    }else{
411        $xlink .= DOKU_SCRIPT.'?do=export_'.$format.$sep.'id='.$id;
412        if($more) $xlink .= $sep.$more;
413    }
414
415    return $xlink;
416}
417
418/**
419 * Build a link to a media file
420 *
421 * Will return a link to the detail page if $direct is false
422 *
423 * The $more parameter should always be given as array, the function then
424 * will strip default parameters to produce even cleaner URLs
425 *
426 * @param string  $id     - the media file id or URL
427 * @param mixed   $more   - string or array with additional parameters
428 * @param boolean $direct - link to detail page if false
429 * @param string  $sep    - URL parameter separator
430 * @param boolean $abs    - Create an absolute URL
431 */
432function ml($id='',$more='',$direct=true,$sep='&amp;',$abs=false){
433    global $conf;
434    if(is_array($more)){
435        // strip defaults for shorter URLs
436        if(isset($more['cache']) && $more['cache'] == 'cache') unset($more['cache']);
437        if(!$more['w']) unset($more['w']);
438        if(!$more['h']) unset($more['h']);
439        if(isset($more['id']) && $direct) unset($more['id']);
440        $more = buildURLparams($more,$sep);
441    }else{
442        $more = str_replace('cache=cache','',$more); //skip default
443        $more = str_replace(',,',',',$more);
444        $more = str_replace(',',$sep,$more);
445    }
446
447    if($abs){
448        $xlink = DOKU_URL;
449    }else{
450        $xlink = DOKU_BASE;
451    }
452
453    // external URLs are always direct without rewriting
454    if(preg_match('#^(https?|ftp)://#i',$id)){
455        $xlink .= 'lib/exe/fetch.php';
456        // add hash:
457        $xlink .= '?hash='.substr(md5(auth_cookiesalt().$id),0,6);
458        if($more){
459            $xlink .= $sep.$more;
460            $xlink .= $sep.'media='.rawurlencode($id);
461        }else{
462            $xlink .= $sep.'media='.rawurlencode($id);
463        }
464        return $xlink;
465    }
466
467    $id = idfilter($id);
468
469    // decide on scriptname
470    if($direct){
471        if($conf['userewrite'] == 1){
472            $script = '_media';
473        }else{
474            $script = 'lib/exe/fetch.php';
475        }
476    }else{
477        if($conf['userewrite'] == 1){
478            $script = '_detail';
479        }else{
480            $script = 'lib/exe/detail.php';
481        }
482    }
483
484    // build URL based on rewrite mode
485    if($conf['userewrite']){
486        $xlink .= $script.'/'.$id;
487        if($more) $xlink .= '?'.$more;
488    }else{
489        if($more){
490            $xlink .= $script.'?'.$more;
491            $xlink .= $sep.'media='.$id;
492        }else{
493            $xlink .= $script.'?media='.$id;
494        }
495    }
496
497    return $xlink;
498}
499
500
501
502/**
503 * Just builds a link to a script
504 *
505 * @todo   maybe obsolete
506 * @author Andreas Gohr <andi@splitbrain.org>
507 */
508function script($script='doku.php'){
509    return DOKU_BASE.DOKU_SCRIPT;
510}
511
512/**
513 * Spamcheck against wordlist
514 *
515 * Checks the wikitext against a list of blocked expressions
516 * returns true if the text contains any bad words
517 *
518 * Triggers COMMON_WORDBLOCK_BLOCKED
519 *
520 *  Action Plugins can use this event to inspect the blocked data
521 *  and gain information about the user who was blocked.
522 *
523 *  Event data:
524 *    data['matches']  - array of matches
525 *    data['userinfo'] - information about the blocked user
526 *      [ip]           - ip address
527 *      [user]         - username (if logged in)
528 *      [mail]         - mail address (if logged in)
529 *      [name]         - real name (if logged in)
530 *
531 * @author Andreas Gohr <andi@splitbrain.org>
532 * @author Michael Klier <chi@chimeric.de>
533 * @param  string $text - optional text to check, if not given the globals are used
534 * @return bool         - true if a spam word was found
535 */
536function checkwordblock($text=''){
537    global $TEXT;
538    global $PRE;
539    global $SUF;
540    global $conf;
541    global $INFO;
542
543    if(!$conf['usewordblock']) return false;
544
545    if(!$text) $text = "$PRE $TEXT $SUF";
546
547    // we prepare the text a tiny bit to prevent spammers circumventing URL checks
548    $text = preg_replace('!(\b)(www\.[\w.:?\-;,]+?\.[\w.:?\-;,]+?[\w/\#~:.?+=&%@\!\-.:?\-;,]+?)([.:?\-;,]*[^\w/\#~:.?+=&%@\!\-.:?\-;,])!i','\1http://\2 \2\3',$text);
549
550    $wordblocks = getWordblocks();
551    // how many lines to read at once (to work around some PCRE limits)
552    if(version_compare(phpversion(),'4.3.0','<')){
553        // old versions of PCRE define a maximum of parenthesises even if no
554        // backreferences are used - the maximum is 99
555        // this is very bad performancewise and may even be too high still
556        $chunksize = 40;
557    }else{
558        // read file in chunks of 200 - this should work around the
559        // MAX_PATTERN_SIZE in modern PCRE
560        $chunksize = 200;
561    }
562    while($blocks = array_splice($wordblocks,0,$chunksize)){
563        $re = array();
564        // build regexp from blocks
565        foreach($blocks as $block){
566            $block = preg_replace('/#.*$/','',$block);
567            $block = trim($block);
568            if(empty($block)) continue;
569            $re[]  = $block;
570        }
571        if(count($re) && preg_match('#('.join('|',$re).')#si',$text,$matches)) {
572            // prepare event data
573            $data['matches'] = $matches;
574            $data['userinfo']['ip'] = $_SERVER['REMOTE_ADDR'];
575            if($_SERVER['REMOTE_USER']) {
576                $data['userinfo']['user'] = $_SERVER['REMOTE_USER'];
577                $data['userinfo']['name'] = $INFO['userinfo']['name'];
578                $data['userinfo']['mail'] = $INFO['userinfo']['mail'];
579            }
580            $callback = create_function('', 'return true;');
581            return trigger_event('COMMON_WORDBLOCK_BLOCKED', $data, $callback, true);
582        }
583    }
584    return false;
585}
586
587/**
588 * Return the IP of the client
589 *
590 * Honours X-Forwarded-For and X-Real-IP Proxy Headers
591 *
592 * It returns a comma separated list of IPs if the above mentioned
593 * headers are set. If the single parameter is set, it tries to return
594 * a routable public address, prefering the ones suplied in the X
595 * headers
596 *
597 * @param  boolean $single If set only a single IP is returned
598 * @author Andreas Gohr <andi@splitbrain.org>
599 */
600function clientIP($single=false){
601    $ip = array();
602    $ip[] = $_SERVER['REMOTE_ADDR'];
603    if(!empty($_SERVER['HTTP_X_FORWARDED_FOR']))
604        $ip = array_merge($ip,explode(',',$_SERVER['HTTP_X_FORWARDED_FOR']));
605    if(!empty($_SERVER['HTTP_X_REAL_IP']))
606        $ip = array_merge($ip,explode(',',$_SERVER['HTTP_X_REAL_IP']));
607
608    // some IPv4/v6 regexps borrowed from Feyd
609    // see: http://forums.devnetwork.net/viewtopic.php?f=38&t=53479
610    $dec_octet = '(?:25[0-5]|2[0-4]\d|1\d\d|[1-9]\d|[0-9])';
611    $hex_digit = '[A-Fa-f0-9]';
612    $h16 = "{$hex_digit}{1,4}";
613    $IPv4Address = "$dec_octet\\.$dec_octet\\.$dec_octet\\.$dec_octet";
614    $ls32 = "(?:$h16:$h16|$IPv4Address)";
615    $IPv6Address =
616        "(?:(?:{$IPv4Address})|(?:".
617        "(?:$h16:){6}$ls32" .
618        "|::(?:$h16:){5}$ls32" .
619        "|(?:$h16)?::(?:$h16:){4}$ls32" .
620        "|(?:(?:$h16:){0,1}$h16)?::(?:$h16:){3}$ls32" .
621        "|(?:(?:$h16:){0,2}$h16)?::(?:$h16:){2}$ls32" .
622        "|(?:(?:$h16:){0,3}$h16)?::(?:$h16:){1}$ls32" .
623        "|(?:(?:$h16:){0,4}$h16)?::$ls32" .
624        "|(?:(?:$h16:){0,5}$h16)?::$h16" .
625        "|(?:(?:$h16:){0,6}$h16)?::" .
626        ")(?:\\/(?:12[0-8]|1[0-1][0-9]|[1-9][0-9]|[0-9]))?)";
627
628    // remove any non-IP stuff
629    $cnt = count($ip);
630    $match = array();
631    for($i=0; $i<$cnt; $i++){
632        if(preg_match("/^$IPv4Address$/",$ip[$i],$match) || preg_match("/^$IPv6Address$/",$ip[$i],$match)) {
633            $ip[$i] = $match[0];
634        } else {
635            $ip[$i] = '';
636        }
637        if(empty($ip[$i])) unset($ip[$i]);
638    }
639    $ip = array_values(array_unique($ip));
640    if(!$ip[0]) $ip[0] = '0.0.0.0'; // for some strange reason we don't have a IP
641
642    if(!$single) return join(',',$ip);
643
644    // decide which IP to use, trying to avoid local addresses
645    $ip = array_reverse($ip);
646    foreach($ip as $i){
647        if(preg_match('/^(127\.|10\.|192\.168\.|172\.((1[6-9])|(2[0-9])|(3[0-1]))\.)/',$i)){
648            continue;
649        }else{
650            return $i;
651        }
652    }
653    // still here? just use the first (last) address
654    return $ip[0];
655}
656
657/**
658 * Check if the browser is on a mobile device
659 *
660 * Adapted from the example code at url below
661 *
662 * @link http://www.brainhandles.com/2007/10/15/detecting-mobile-browsers/#code
663 */
664function clientismobile(){
665
666    if(isset($_SERVER['HTTP_X_WAP_PROFILE'])) return true;
667
668    if(preg_match('/wap\.|\.wap/i',$_SERVER['HTTP_ACCEPT'])) return true;
669
670    if(!isset($_SERVER['HTTP_USER_AGENT'])) return false;
671
672    $uamatches = 'midp|j2me|avantg|docomo|novarra|palmos|palmsource|240x320|opwv|chtml|pda|windows ce|mmp\/|blackberry|mib\/|symbian|wireless|nokia|hand|mobi|phone|cdm|up\.b|audio|SIE\-|SEC\-|samsung|HTC|mot\-|mitsu|sagem|sony|alcatel|lg|erics|vx|NEC|philips|mmm|xx|panasonic|sharp|wap|sch|rover|pocket|benq|java|pt|pg|vox|amoi|bird|compal|kg|voda|sany|kdd|dbt|sendo|sgh|gradi|jb|\d\d\di|moto';
673
674    if(preg_match("/$uamatches/i",$_SERVER['HTTP_USER_AGENT'])) return true;
675
676    return false;
677}
678
679
680/**
681 * Convert one or more comma separated IPs to hostnames
682 *
683 * @author Glen Harris <astfgl@iamnota.org>
684 * @returns a comma separated list of hostnames
685 */
686function gethostsbyaddrs($ips){
687    $hosts = array();
688    $ips = explode(',',$ips);
689
690    if(is_array($ips)) {
691        foreach($ips as $ip){
692            $hosts[] = gethostbyaddr(trim($ip));
693        }
694        return join(',',$hosts);
695    } else {
696        return gethostbyaddr(trim($ips));
697    }
698}
699
700/**
701 * Checks if a given page is currently locked.
702 *
703 * removes stale lockfiles
704 *
705 * @author Andreas Gohr <andi@splitbrain.org>
706 */
707function checklock($id){
708    global $conf;
709    $lock = wikiLockFN($id);
710
711    //no lockfile
712    if(!@file_exists($lock)) return false;
713
714    //lockfile expired
715    if((time() - filemtime($lock)) > $conf['locktime']){
716        @unlink($lock);
717        return false;
718    }
719
720    //my own lock
721    $ip = io_readFile($lock);
722    if( ($ip == clientIP()) || ($ip == $_SERVER['REMOTE_USER']) ){
723        return false;
724    }
725
726    return $ip;
727}
728
729/**
730 * Lock a page for editing
731 *
732 * @author Andreas Gohr <andi@splitbrain.org>
733 */
734function lock($id){
735    global $conf;
736
737    if($conf['locktime'] == 0){
738        return;
739    }
740
741    $lock = wikiLockFN($id);
742    if($_SERVER['REMOTE_USER']){
743        io_saveFile($lock,$_SERVER['REMOTE_USER']);
744    }else{
745        io_saveFile($lock,clientIP());
746    }
747}
748
749/**
750 * Unlock a page if it was locked by the user
751 *
752 * @author Andreas Gohr <andi@splitbrain.org>
753 * @return bool true if a lock was removed
754 */
755function unlock($id){
756    $lock = wikiLockFN($id);
757    if(@file_exists($lock)){
758        $ip = io_readFile($lock);
759        if( ($ip == clientIP()) || ($ip == $_SERVER['REMOTE_USER']) ){
760            @unlink($lock);
761            return true;
762        }
763    }
764    return false;
765}
766
767/**
768 * convert line ending to unix format
769 *
770 * @see    formText() for 2crlf conversion
771 * @author Andreas Gohr <andi@splitbrain.org>
772 */
773function cleanText($text){
774    $text = preg_replace("/(\015\012)|(\015)/","\012",$text);
775    return $text;
776}
777
778/**
779 * Prepares text for print in Webforms by encoding special chars.
780 * It also converts line endings to Windows format which is
781 * pseudo standard for webforms.
782 *
783 * @see    cleanText() for 2unix conversion
784 * @author Andreas Gohr <andi@splitbrain.org>
785 */
786function formText($text){
787    $text = str_replace("\012","\015\012",$text);
788    return htmlspecialchars($text);
789}
790
791/**
792 * Returns the specified local text in raw format
793 *
794 * @author Andreas Gohr <andi@splitbrain.org>
795 */
796function rawLocale($id){
797    return io_readFile(localeFN($id));
798}
799
800/**
801 * Returns the raw WikiText
802 *
803 * @author Andreas Gohr <andi@splitbrain.org>
804 */
805function rawWiki($id,$rev=''){
806    return io_readWikiPage(wikiFN($id, $rev), $id, $rev);
807}
808
809/**
810 * Returns the pagetemplate contents for the ID's namespace
811 *
812 * @author Andreas Gohr <andi@splitbrain.org>
813 */
814function pageTemplate($data){
815    $id = $data[0];
816    global $conf;
817
818    $path = dirname(wikiFN($id));
819
820    if(@file_exists($path.'/_template.txt')){
821        $tpl = io_readFile($path.'/_template.txt');
822    }else{
823        // search upper namespaces for templates
824        $len = strlen(rtrim($conf['datadir'],'/'));
825        while (strlen($path) >= $len){
826            if(@file_exists($path.'/__template.txt')){
827                $tpl = io_readFile($path.'/__template.txt');
828                break;
829            }
830            $path = substr($path, 0, strrpos($path, '/'));
831        }
832    }
833    return isset($tpl) ? parsePageTemplate($tpl, $id) : '';
834}
835
836/**
837 * Performs common page template replacements
838 *
839 * @author Andreas Gohr <andi@splitbrain.org>
840 */
841function parsePageTemplate($tpl, $id) {
842    global $USERINFO;
843    global $conf;
844
845    // replace placeholders
846    $file = noNS($id);
847    $page = strtr($file,'_',' ');
848
849    $tpl = str_replace(array(
850                '@ID@',
851                '@NS@',
852                '@FILE@',
853                '@!FILE@',
854                '@!FILE!@',
855                '@PAGE@',
856                '@!PAGE@',
857                '@!!PAGE@',
858                '@!PAGE!@',
859                '@USER@',
860                '@NAME@',
861                '@MAIL@',
862                '@DATE@',
863                ),
864            array(
865                $id,
866                getNS($id),
867                $file,
868                utf8_ucfirst($file),
869                utf8_strtoupper($file),
870                $page,
871                utf8_ucfirst($page),
872                utf8_ucwords($page),
873                utf8_strtoupper($page),
874                $_SERVER['REMOTE_USER'],
875                $USERINFO['name'],
876                $USERINFO['mail'],
877                $conf['dformat'],
878                ), $tpl);
879
880    // we need the callback to work around strftime's char limit
881    $tpl = preg_replace_callback('/%./',create_function('$m','return strftime($m[0]);'),$tpl);
882
883    return $tpl;
884}
885
886/**
887 * Returns the raw Wiki Text in three slices.
888 *
889 * The range parameter needs to have the form "from-to"
890 * and gives the range of the section in bytes - no
891 * UTF-8 awareness is needed.
892 * The returned order is prefix, section and suffix.
893 *
894 * @author Andreas Gohr <andi@splitbrain.org>
895 */
896function rawWikiSlices($range,$id,$rev=''){
897    list($from,$to) = explode('-',$range,2);
898    $text = io_readWikiPage(wikiFN($id, $rev), $id, $rev);
899    if(!$from) $from = 0;
900    if(!$to)   $to   = strlen($text)+1;
901
902    $slices[0] = substr($text,0,$from-1);
903    $slices[1] = substr($text,$from-1,$to-$from);
904    $slices[2] = substr($text,$to);
905
906    return $slices;
907}
908
909/**
910 * Joins wiki text slices
911 *
912 * function to join the text slices with correct lineendings again.
913 * When the pretty parameter is set to true it adds additional empty
914 * lines between sections if needed (used on saving).
915 *
916 * @author Andreas Gohr <andi@splitbrain.org>
917 */
918function con($pre,$text,$suf,$pretty=false){
919    if($pretty){
920        if($pre && substr($pre,-1) != "\n") $pre .= "\n";
921        if($suf && substr($text,-1) != "\n") $text .= "\n";
922    }
923
924    // Avoid double newline above section when saving section edit
925    //if($pre) $pre .= "\n";
926    if($suf) $text .= "\n";
927    return $pre.$text.$suf;
928}
929
930/**
931 * Saves a wikitext by calling io_writeWikiPage.
932 * Also directs changelog and attic updates.
933 *
934 * @author Andreas Gohr <andi@splitbrain.org>
935 * @author Ben Coburn <btcoburn@silicodon.net>
936 */
937function saveWikiText($id,$text,$summary,$minor=false){
938    /* Note to developers:
939       This code is subtle and delicate. Test the behavior of
940       the attic and changelog with dokuwiki and external edits
941       after any changes. External edits change the wiki page
942       directly without using php or dokuwiki.
943     */
944    global $conf;
945    global $lang;
946    global $REV;
947    // ignore if no changes were made
948    if($text == rawWiki($id,'')){
949        return;
950    }
951
952    $file = wikiFN($id);
953    $old = @filemtime($file); // from page
954    $wasRemoved = empty($text);
955    $wasCreated = !@file_exists($file);
956    $wasReverted = ($REV==true);
957    $newRev = false;
958    $oldRev = getRevisions($id, -1, 1, 1024); // from changelog
959    $oldRev = (int)(empty($oldRev)?0:$oldRev[0]);
960    if(!@file_exists(wikiFN($id, $old)) && @file_exists($file) && $old>=$oldRev) {
961        // add old revision to the attic if missing
962        saveOldRevision($id);
963        // add a changelog entry if this edit came from outside dokuwiki
964        if ($old>$oldRev) {
965            addLogEntry($old, $id, DOKU_CHANGE_TYPE_EDIT, $lang['external_edit'], '', array('ExternalEdit'=>true));
966            // remove soon to be stale instructions
967            $cache = new cache_instructions($id, $file);
968            $cache->removeCache();
969        }
970    }
971
972    if ($wasRemoved){
973        // Send "update" event with empty data, so plugins can react to page deletion
974        $data = array(array($file, '', false), getNS($id), noNS($id), false);
975        trigger_event('IO_WIKIPAGE_WRITE', $data);
976        // pre-save deleted revision
977        @touch($file);
978        clearstatcache();
979        $newRev = saveOldRevision($id);
980        // remove empty file
981        @unlink($file);
982        // remove old meta info...
983        $mfiles = metaFiles($id);
984        $changelog = metaFN($id, '.changes');
985        $metadata  = metaFN($id, '.meta');
986        foreach ($mfiles as $mfile) {
987            // but keep per-page changelog to preserve page history and keep meta data
988            if (@file_exists($mfile) && $mfile!==$changelog && $mfile!==$metadata) { @unlink($mfile); }
989        }
990        // purge meta data
991        p_purge_metadata($id);
992        $del = true;
993        // autoset summary on deletion
994        if(empty($summary)) $summary = $lang['deleted'];
995        // remove empty namespaces
996        io_sweepNS($id, 'datadir');
997        io_sweepNS($id, 'mediadir');
998    }else{
999        // save file (namespace dir is created in io_writeWikiPage)
1000        io_writeWikiPage($file, $text, $id);
1001        // pre-save the revision, to keep the attic in sync
1002        $newRev = saveOldRevision($id);
1003        $del = false;
1004    }
1005
1006    // select changelog line type
1007    $extra = '';
1008    $type = DOKU_CHANGE_TYPE_EDIT;
1009    if ($wasReverted) {
1010        $type = DOKU_CHANGE_TYPE_REVERT;
1011        $extra = $REV;
1012    }
1013    else if ($wasCreated) { $type = DOKU_CHANGE_TYPE_CREATE; }
1014    else if ($wasRemoved) { $type = DOKU_CHANGE_TYPE_DELETE; }
1015    else if ($minor && $conf['useacl'] && $_SERVER['REMOTE_USER']) { $type = DOKU_CHANGE_TYPE_MINOR_EDIT; } //minor edits only for logged in users
1016
1017    addLogEntry($newRev, $id, $type, $summary, $extra);
1018    // send notify mails
1019    notify($id,'admin',$old,$summary,$minor);
1020    notify($id,'subscribers',$old,$summary,$minor);
1021
1022    // update the purgefile (timestamp of the last time anything within the wiki was changed)
1023    io_saveFile($conf['cachedir'].'/purgefile',time());
1024
1025    // if useheading is enabled, purge the cache of all linking pages
1026    if(useHeading('content')){
1027        require_once(DOKU_INC.'inc/fulltext.php');
1028        $pages = ft_backlinks($id);
1029        foreach ($pages as $page) {
1030            $cache = new cache_renderer($page, wikiFN($page), 'xhtml');
1031            $cache->removeCache();
1032        }
1033    }
1034}
1035
1036/**
1037 * moves the current version to the attic and returns its
1038 * revision date
1039 *
1040 * @author Andreas Gohr <andi@splitbrain.org>
1041 */
1042function saveOldRevision($id){
1043    global $conf;
1044    $oldf = wikiFN($id);
1045    if(!@file_exists($oldf)) return '';
1046    $date = filemtime($oldf);
1047    $newf = wikiFN($id,$date);
1048    io_writeWikiPage($newf, rawWiki($id), $id, $date);
1049    return $date;
1050}
1051
1052/**
1053 * Sends a notify mail on page change or registration
1054 *
1055 * @param  string  $id       The changed page
1056 * @param  string  $who      Who to notify (admin|subscribers|register)
1057 * @param  int     $rev      Old page revision
1058 * @param  string  $summary  What changed
1059 * @param  boolean $minor    Is this a minor edit?
1060 * @param  array   $replace  Additional string substitutions, @KEY@ to be replaced by value
1061 *
1062 * @author Andreas Gohr <andi@splitbrain.org>
1063 */
1064function notify($id,$who,$rev='',$summary='',$minor=false,$replace=array()){
1065    global $lang;
1066    global $conf;
1067    global $INFO;
1068
1069    // decide if there is something to do
1070    if($who == 'admin'){
1071        if(empty($conf['notify'])) return; //notify enabled?
1072        $text = rawLocale('mailtext');
1073        $to   = $conf['notify'];
1074        $bcc  = '';
1075    }elseif($who == 'subscribers'){
1076        if(!$conf['subscribers']) return; //subscribers enabled?
1077        if($conf['useacl'] && $_SERVER['REMOTE_USER'] && $minor) return; //skip minors
1078        $data = array('id' => $id, 'addresslist' => '', 'self' => false);
1079        trigger_event('COMMON_NOTIFY_ADDRESSLIST', $data,
1080                      'subscription_addresslist');
1081        $bcc = $data['addresslist'];
1082        if(empty($bcc)) return;
1083        $to   = '';
1084        $text = rawLocale('subscr_single');
1085    }elseif($who == 'register'){
1086        if(empty($conf['registernotify'])) return;
1087        $text = rawLocale('registermail');
1088        $to   = $conf['registernotify'];
1089        $bcc  = '';
1090    }else{
1091        return; //just to be safe
1092    }
1093
1094    $ip   = clientIP();
1095    $text = str_replace('@DATE@',dformat(),$text);
1096    $text = str_replace('@BROWSER@',$_SERVER['HTTP_USER_AGENT'],$text);
1097    $text = str_replace('@IPADDRESS@',$ip,$text);
1098    $text = str_replace('@HOSTNAME@',gethostsbyaddrs($ip),$text);
1099    $text = str_replace('@NEWPAGE@',wl($id,'',true,'&'),$text);
1100    $text = str_replace('@PAGE@',$id,$text);
1101    $text = str_replace('@TITLE@',$conf['title'],$text);
1102    $text = str_replace('@DOKUWIKIURL@',DOKU_URL,$text);
1103    $text = str_replace('@SUMMARY@',$summary,$text);
1104    $text = str_replace('@USER@',$_SERVER['REMOTE_USER'],$text);
1105
1106    foreach ($replace as $key => $substitution) {
1107        $text = str_replace('@'.strtoupper($key).'@',$substitution, $text);
1108    }
1109
1110    if($who == 'register'){
1111        $subject = $lang['mail_new_user'].' '.$summary;
1112    }elseif($rev){
1113        $subject = $lang['mail_changed'].' '.$id;
1114        $text = str_replace('@OLDPAGE@',wl($id,"rev=$rev",true,'&'),$text);
1115        require_once(DOKU_INC.'inc/DifferenceEngine.php');
1116        $df  = new Diff(explode("\n",rawWiki($id,$rev)),
1117                        explode("\n",rawWiki($id)));
1118        $dformat = new UnifiedDiffFormatter();
1119        $diff    = $dformat->format($df);
1120    }else{
1121        $subject=$lang['mail_newpage'].' '.$id;
1122        $text = str_replace('@OLDPAGE@','none',$text);
1123        $diff = rawWiki($id);
1124    }
1125    $text = str_replace('@DIFF@',$diff,$text);
1126    $subject = '['.$conf['title'].'] '.$subject;
1127
1128    $from = $conf['mailfrom'];
1129    $from = str_replace('@USER@',$_SERVER['REMOTE_USER'],$from);
1130    $from = str_replace('@NAME@',$INFO['userinfo']['name'],$from);
1131    $from = str_replace('@MAIL@',$INFO['userinfo']['mail'],$from);
1132
1133    mail_send($to,$subject,$text,$from,'',$bcc);
1134}
1135
1136/**
1137 * extracts the query from a search engine referrer
1138 *
1139 * @author Andreas Gohr <andi@splitbrain.org>
1140 * @author Todd Augsburger <todd@rollerorgans.com>
1141 */
1142function getGoogleQuery(){
1143    if (!isset($_SERVER['HTTP_REFERER'])) {
1144        return '';
1145    }
1146    $url = parse_url($_SERVER['HTTP_REFERER']);
1147
1148    $query = array();
1149
1150    // temporary workaround against PHP bug #49733
1151    // see http://bugs.php.net/bug.php?id=49733
1152    if(UTF8_MBSTRING) $enc = mb_internal_encoding();
1153    parse_str($url['query'],$query);
1154    if(UTF8_MBSTRING) mb_internal_encoding($enc);
1155
1156    $q = '';
1157    if(isset($query['q']))
1158        $q = $query['q'];        // google, live/msn, aol, ask, altavista, alltheweb, gigablast
1159    elseif(isset($query['p']))
1160        $q = $query['p'];        // yahoo
1161    elseif(isset($query['query']))
1162        $q = $query['query'];    // lycos, netscape, clusty, hotbot
1163    elseif(preg_match("#a9\.com#i",$url['host'])) // a9
1164        $q = urldecode(ltrim($url['path'],'/'));
1165
1166    if($q === '') return '';
1167    $q = preg_split('/[\s\'"\\\\`()\]\[?:!\.{};,#+*<>\\/]+/',$q,-1,PREG_SPLIT_NO_EMPTY);
1168    return $q;
1169}
1170
1171/**
1172 * Try to set correct locale
1173 *
1174 * @deprecated No longer used
1175 * @author     Andreas Gohr <andi@splitbrain.org>
1176 */
1177function setCorrectLocale(){
1178    global $conf;
1179    global $lang;
1180
1181    $enc = strtoupper($lang['encoding']);
1182    foreach ($lang['locales'] as $loc){
1183        //try locale
1184        if(@setlocale(LC_ALL,$loc)) return;
1185        //try loceale with encoding
1186        if(@setlocale(LC_ALL,"$loc.$enc")) return;
1187    }
1188    //still here? try to set from environment
1189    @setlocale(LC_ALL,"");
1190}
1191
1192/**
1193 * Return the human readable size of a file
1194 *
1195 * @param       int    $size   A file size
1196 * @param       int    $dec    A number of decimal places
1197 * @author      Martin Benjamin <b.martin@cybernet.ch>
1198 * @author      Aidan Lister <aidan@php.net>
1199 * @version     1.0.0
1200 */
1201function filesize_h($size, $dec = 1){
1202    $sizes = array('B', 'KB', 'MB', 'GB');
1203    $count = count($sizes);
1204    $i = 0;
1205
1206    while ($size >= 1024 && ($i < $count - 1)) {
1207        $size /= 1024;
1208        $i++;
1209    }
1210
1211    return round($size, $dec) . ' ' . $sizes[$i];
1212}
1213
1214/**
1215 * Return the given timestamp as human readable, fuzzy age
1216 *
1217 * @author Andreas Gohr <gohr@cosmocode.de>
1218 */
1219function datetime_h($dt){
1220    global $lang;
1221
1222    $ago = time() - $dt;
1223    if($ago > 24*60*60*30*12*2){
1224        return sprintf($lang['years'], round($ago/(24*60*60*30*12)));
1225    }
1226    if($ago > 24*60*60*30*2){
1227        return sprintf($lang['months'], round($ago/(24*60*60*30)));
1228    }
1229    if($ago > 24*60*60*7*2){
1230        return sprintf($lang['weeks'], round($ago/(24*60*60*7)));
1231    }
1232    if($ago > 24*60*60*2){
1233        return sprintf($lang['days'], round($ago/(24*60*60)));
1234    }
1235    if($ago > 60*60*2){
1236        return sprintf($lang['hours'], round($ago/(60*60)));
1237    }
1238    if($ago > 60*2){
1239        return sprintf($lang['minutes'], round($ago/(60)));
1240    }
1241    return sprintf($lang['seconds'], $ago);
1242}
1243
1244/**
1245 * Wraps around strftime but provides support for fuzzy dates
1246 *
1247 * The format default to $conf['dformat']. It is passed to
1248 * strftime - %f can be used to get the value from datetime_h()
1249 *
1250 * @see datetime_h
1251 * @author Andreas Gohr <gohr@cosmocode.de>
1252 */
1253function dformat($dt=null,$format=''){
1254    global $conf;
1255
1256    if(is_null($dt)) $dt = time();
1257    $dt = (int) $dt;
1258    if(!$format) $format = $conf['dformat'];
1259
1260    $format = str_replace('%f',datetime_h($dt),$format);
1261    return strftime($format,$dt);
1262}
1263
1264/**
1265 * return an obfuscated email address in line with $conf['mailguard'] setting
1266 *
1267 * @author Harry Fuecks <hfuecks@gmail.com>
1268 * @author Christopher Smith <chris@jalakai.co.uk>
1269 */
1270function obfuscate($email) {
1271    global $conf;
1272
1273    switch ($conf['mailguard']) {
1274        case 'visible' :
1275            $obfuscate = array('@' => ' [at] ', '.' => ' [dot] ', '-' => ' [dash] ');
1276            return strtr($email, $obfuscate);
1277
1278        case 'hex' :
1279            $encode = '';
1280            $len = strlen($email);
1281            for ($x=0; $x < $len; $x++){
1282                $encode .= '&#x' . bin2hex($email{$x}).';';
1283            }
1284            return $encode;
1285
1286        case 'none' :
1287        default :
1288            return $email;
1289    }
1290}
1291
1292/**
1293 * Removes quoting backslashes
1294 *
1295 * @author Andreas Gohr <andi@splitbrain.org>
1296 */
1297function unslash($string,$char="'"){
1298    return str_replace('\\'.$char,$char,$string);
1299}
1300
1301/**
1302 * Convert php.ini shorthands to byte
1303 *
1304 * @author <gilthans dot NO dot SPAM at gmail dot com>
1305 * @link   http://de3.php.net/manual/en/ini.core.php#79564
1306 */
1307function php_to_byte($v){
1308    $l = substr($v, -1);
1309    $ret = substr($v, 0, -1);
1310    switch(strtoupper($l)){
1311        case 'P':
1312            $ret *= 1024;
1313        case 'T':
1314            $ret *= 1024;
1315        case 'G':
1316            $ret *= 1024;
1317        case 'M':
1318            $ret *= 1024;
1319        case 'K':
1320            $ret *= 1024;
1321        break;
1322    }
1323    return $ret;
1324}
1325
1326/**
1327 * Wrapper around preg_quote adding the default delimiter
1328 */
1329function preg_quote_cb($string){
1330    return preg_quote($string,'/');
1331}
1332
1333/**
1334 * Shorten a given string by removing data from the middle
1335 *
1336 * You can give the string in two parts, the first part $keep
1337 * will never be shortened. The second part $short will be cut
1338 * in the middle to shorten but only if at least $min chars are
1339 * left to display it. Otherwise it will be left off.
1340 *
1341 * @param string $keep   the part to keep
1342 * @param string $short  the part to shorten
1343 * @param int    $max    maximum chars you want for the whole string
1344 * @param int    $min    minimum number of chars to have left for middle shortening
1345 * @param string $char   the shortening character to use
1346 */
1347function shorten($keep,$short,$max,$min=9,$char='…'){
1348    $max = $max - utf8_strlen($keep);
1349    if($max < $min) return $keep;
1350    $len = utf8_strlen($short);
1351    if($len <= $max) return $keep.$short;
1352    $half = floor($max/2);
1353    return $keep.utf8_substr($short,0,$half-1).$char.utf8_substr($short,$len-$half);
1354}
1355
1356/**
1357 * Return the users realname or e-mail address for use
1358 * in page footer and recent changes pages
1359 *
1360 * @author Andy Webber <dokuwiki AT andywebber DOT com>
1361 */
1362function editorinfo($username){
1363    global $conf;
1364    global $auth;
1365
1366    switch($conf['showuseras']){
1367        case 'username':
1368        case 'email':
1369        case 'email_link':
1370            if($auth) $info = $auth->getUserData($username);
1371            break;
1372        default:
1373            return hsc($username);
1374    }
1375
1376    if(isset($info) && $info) {
1377        switch($conf['showuseras']){
1378            case 'username':
1379                return hsc($info['name']);
1380            case 'email':
1381                return obfuscate($info['mail']);
1382            case 'email_link':
1383                $mail=obfuscate($info['mail']);
1384                return '<a href="mailto:'.$mail.'">'.$mail.'</a>';
1385            default:
1386                return hsc($username);
1387        }
1388    } else {
1389        return hsc($username);
1390    }
1391}
1392
1393/**
1394 * Returns the path to a image file for the currently chosen license.
1395 * When no image exists, returns an empty string
1396 *
1397 * @author Andreas Gohr <andi@splitbrain.org>
1398 * @param  string $type - type of image 'badge' or 'button'
1399 */
1400function license_img($type){
1401    global $license;
1402    global $conf;
1403    if(!$conf['license']) return '';
1404    if(!is_array($license[$conf['license']])) return '';
1405    $lic = $license[$conf['license']];
1406    $try = array();
1407    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.png';
1408    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.gif';
1409    if(substr($conf['license'],0,3) == 'cc-'){
1410        $try[] = 'lib/images/license/'.$type.'/cc.png';
1411    }
1412    foreach($try as $src){
1413        if(@file_exists(DOKU_INC.$src)) return $src;
1414    }
1415    return '';
1416}
1417
1418/**
1419 * Checks if the given amount of memory is available
1420 *
1421 * If the memory_get_usage() function is not available the
1422 * function just assumes $bytes of already allocated memory
1423 *
1424 * @param  int $mem  Size of memory you want to allocate in bytes
1425 * @param  int $used already allocated memory (see above)
1426 * @author Filip Oscadal <webmaster@illusionsoftworks.cz>
1427 * @author Andreas Gohr <andi@splitbrain.org>
1428 */
1429function is_mem_available($mem,$bytes=1048576){
1430    $limit = trim(ini_get('memory_limit'));
1431    if(empty($limit)) return true; // no limit set!
1432
1433    // parse limit to bytes
1434    $limit = php_to_byte($limit);
1435
1436    // get used memory if possible
1437    if(function_exists('memory_get_usage')){
1438        $used = memory_get_usage();
1439    }else{
1440        $used = $bytes;
1441    }
1442
1443    if($used+$mem > $limit){
1444        return false;
1445    }
1446
1447    return true;
1448}
1449
1450/**
1451 * Send a HTTP redirect to the browser
1452 *
1453 * Works arround Microsoft IIS cookie sending bug. Exits the script.
1454 *
1455 * @link   http://support.microsoft.com/kb/q176113/
1456 * @author Andreas Gohr <andi@splitbrain.org>
1457 */
1458function send_redirect($url){
1459    // always close the session
1460    session_write_close();
1461
1462    // check if running on IIS < 6 with CGI-PHP
1463    if( isset($_SERVER['SERVER_SOFTWARE']) && isset($_SERVER['GATEWAY_INTERFACE']) &&
1464        (strpos($_SERVER['GATEWAY_INTERFACE'],'CGI') !== false) &&
1465        (preg_match('|^Microsoft-IIS/(\d)\.\d$|', trim($_SERVER['SERVER_SOFTWARE']), $matches)) &&
1466        $matches[1] < 6 ){
1467        header('Refresh: 0;url='.$url);
1468    }else{
1469        header('Location: '.$url);
1470    }
1471    exit;
1472}
1473
1474/**
1475 * Validate a value using a set of valid values
1476 *
1477 * This function checks whether a specified value is set and in the array
1478 * $valid_values. If not, the function returns a default value or, if no
1479 * default is specified, throws an exception.
1480 *
1481 * @param string $param        The name of the parameter
1482 * @param array  $valid_values A set of valid values; Optionally a default may
1483 *                             be marked by the key “default”.
1484 * @param array  $array        The array containing the value (typically $_POST
1485 *                             or $_GET)
1486 * @param string $exc          The text of the raised exception
1487 *
1488 * @author Adrian Lang <lang@cosmocode.de>
1489 */
1490function valid_input_set($param, $valid_values, $array, $exc = '') {
1491    if (isset($array[$param]) && in_array($array[$param], $valid_values)) {
1492        return $array[$param];
1493    } elseif (isset($valid_values['default'])) {
1494        return $valid_values['default'];
1495    } else {
1496        throw new Exception($exc);
1497    }
1498}
1499
1500//Setup VIM: ex: et ts=2 enc=utf-8 :
1501