xref: /dokuwiki/inc/common.php (revision 957e84c6d04b3287613860d79d564d971531db98) 
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 */
26function hsc($string) {
27    return htmlspecialchars($string, ENT_QUOTES, 'UTF-8');
28}
29
30/**
31 * print a newline terminated string
32 *
33 * You can give an indention as optional parameter
34 *
35 * @author Andreas Gohr <andi@splitbrain.org>
36 */
37function ptln($string, $indent = 0) {
38    echo str_repeat(' ', $indent)."$string\n";
39}
40
41/**
42 * strips control characters (<32) from the given string
43 *
44 * @author Andreas Gohr <andi@splitbrain.org>
45 */
46function stripctl($string) {
47    return preg_replace('/[\x00-\x1F]+/s', '', $string);
48}
49
50/**
51 * Return a secret token to be used for CSRF attack prevention
52 *
53 * @author  Andreas Gohr <andi@splitbrain.org>
54 * @link    http://en.wikipedia.org/wiki/Cross-site_request_forgery
55 * @link    http://christ1an.blogspot.com/2007/04/preventing-csrf-efficiently.html
56 * @return  string
57 */
58function getSecurityToken() {
59    return md5(auth_cookiesalt().session_id().$_SERVER['REMOTE_USER']);
60}
61
62/**
63 * Check the secret CSRF token
64 */
65function checkSecurityToken($token = null) {
66    global $INPUT;
67    if(!$_SERVER['REMOTE_USER']) return true; // no logged in user, no need for a check
68
69    if(is_null($token)) $token = $INPUT->str('sectok');
70    if(getSecurityToken() != $token) {
71        msg('Security Token did not match. Possible CSRF attack.', -1);
72        return false;
73    }
74    return true;
75}
76
77/**
78 * Print a hidden form field with a secret CSRF token
79 *
80 * @author  Andreas Gohr <andi@splitbrain.org>
81 */
82function formSecurityToken($print = true) {
83    $ret = '<div class="no"><input type="hidden" name="sectok" value="'.getSecurityToken().'" /></div>'."\n";
84    if($print) echo $ret;
85    return $ret;
86}
87
88/**
89 * Return info about the current document as associative
90 * array.
91 *
92 * @author Andreas Gohr <andi@splitbrain.org>
93 */
94function pageinfo() {
95    global $ID;
96    global $REV;
97    global $RANGE;
98    global $USERINFO;
99    global $lang;
100
101    // include ID & REV not redundant, as some parts of DokuWiki may temporarily change $ID, e.g. p_wiki_xhtml
102    // FIXME ... perhaps it would be better to ensure the temporary changes weren't necessary
103    $info['id']  = $ID;
104    $info['rev'] = $REV;
105
106    // set info about manager/admin status.
107    $info['isadmin']   = false;
108    $info['ismanager'] = false;
109    if(isset($_SERVER['REMOTE_USER'])) {
110        $sub = new Subscription();
111
112        $info['userinfo']   = $USERINFO;
113        $info['perm']       = auth_quickaclcheck($ID);
114        $info['subscribed'] = $sub->user_subscription();
115        $info['client']     = $_SERVER['REMOTE_USER'];
116
117        if($info['perm'] == AUTH_ADMIN) {
118            $info['isadmin']   = true;
119            $info['ismanager'] = true;
120        } elseif(auth_ismanager()) {
121            $info['ismanager'] = true;
122        }
123
124        // if some outside auth were used only REMOTE_USER is set
125        if(!$info['userinfo']['name']) {
126            $info['userinfo']['name'] = $_SERVER['REMOTE_USER'];
127        }
128
129    } else {
130        $info['perm']       = auth_aclcheck($ID, '', null);
131        $info['subscribed'] = false;
132        $info['client']     = clientIP(true);
133    }
134
135    $info['namespace'] = getNS($ID);
136    $info['locked']    = checklock($ID);
137    $info['filepath']  = fullpath(wikiFN($ID));
138    $info['exists']    = @file_exists($info['filepath']);
139    if($REV) {
140        //check if current revision was meant
141        if($info['exists'] && (@filemtime($info['filepath']) == $REV)) {
142            $REV = '';
143        } elseif($RANGE) {
144            //section editing does not work with old revisions!
145            $REV   = '';
146            $RANGE = '';
147            msg($lang['nosecedit'], 0);
148        } else {
149            //really use old revision
150            $info['filepath'] = fullpath(wikiFN($ID, $REV));
151            $info['exists']   = @file_exists($info['filepath']);
152        }
153    }
154    $info['rev'] = $REV;
155    if($info['exists']) {
156        $info['writable'] = (is_writable($info['filepath']) &&
157            ($info['perm'] >= AUTH_EDIT));
158    } else {
159        $info['writable'] = ($info['perm'] >= AUTH_CREATE);
160    }
161    $info['editable'] = ($info['writable'] && empty($info['locked']));
162    $info['lastmod']  = @filemtime($info['filepath']);
163
164    //load page meta data
165    $info['meta'] = p_get_metadata($ID);
166
167    //who's the editor
168    if($REV) {
169        $revinfo = getRevisionInfo($ID, $REV, 1024);
170    } else {
171        if(is_array($info['meta']['last_change'])) {
172            $revinfo = $info['meta']['last_change'];
173        } else {
174            $revinfo = getRevisionInfo($ID, $info['lastmod'], 1024);
175            // cache most recent changelog line in metadata if missing and still valid
176            if($revinfo !== false) {
177                $info['meta']['last_change'] = $revinfo;
178                p_set_metadata($ID, array('last_change' => $revinfo));
179            }
180        }
181    }
182    //and check for an external edit
183    if($revinfo !== false && $revinfo['date'] != $info['lastmod']) {
184        // cached changelog line no longer valid
185        $revinfo                     = false;
186        $info['meta']['last_change'] = $revinfo;
187        p_set_metadata($ID, array('last_change' => $revinfo));
188    }
189
190    $info['ip']   = $revinfo['ip'];
191    $info['user'] = $revinfo['user'];
192    $info['sum']  = $revinfo['sum'];
193    // See also $INFO['meta']['last_change'] which is the most recent log line for page $ID.
194    // Use $INFO['meta']['last_change']['type']===DOKU_CHANGE_TYPE_MINOR_EDIT in place of $info['minor'].
195
196    if($revinfo['user']) {
197        $info['editor'] = $revinfo['user'];
198    } else {
199        $info['editor'] = $revinfo['ip'];
200    }
201
202    // draft
203    $draft = getCacheName($info['client'].$ID, '.draft');
204    if(@file_exists($draft)) {
205        if(@filemtime($draft) < @filemtime(wikiFN($ID))) {
206            // remove stale draft
207            @unlink($draft);
208        } else {
209            $info['draft'] = $draft;
210        }
211    }
212
213    // mobile detection
214    $info['ismobile'] = clientismobile();
215
216    return $info;
217}
218
219/**
220 * Build an string of URL parameters
221 *
222 * @author Andreas Gohr
223 */
224function buildURLparams($params, $sep = '&amp;') {
225    $url = '';
226    $amp = false;
227    foreach($params as $key => $val) {
228        if($amp) $url .= $sep;
229
230        $url .= rawurlencode($key).'=';
231        $url .= rawurlencode((string) $val);
232        $amp = true;
233    }
234    return $url;
235}
236
237/**
238 * Build an string of html tag attributes
239 *
240 * Skips keys starting with '_', values get HTML encoded
241 *
242 * @author Andreas Gohr
243 */
244function buildAttributes($params, $skipempty = false) {
245    $url   = '';
246    $white = false;
247    foreach($params as $key => $val) {
248        if($key{0} == '_') continue;
249        if($val === '' && $skipempty) continue;
250        if($white) $url .= ' ';
251
252        $url .= $key.'="';
253        $url .= htmlspecialchars($val);
254        $url .= '"';
255        $white = true;
256    }
257    return $url;
258}
259
260/**
261 * This builds the breadcrumb trail and returns it as array
262 *
263 * @author Andreas Gohr <andi@splitbrain.org>
264 */
265function breadcrumbs() {
266    // we prepare the breadcrumbs early for quick session closing
267    static $crumbs = null;
268    if($crumbs != null) return $crumbs;
269
270    global $ID;
271    global $ACT;
272    global $conf;
273
274    //first visit?
275    $crumbs = isset($_SESSION[DOKU_COOKIE]['bc']) ? $_SESSION[DOKU_COOKIE]['bc'] : array();
276    //we only save on show and existing wiki documents
277    $file = wikiFN($ID);
278    if($ACT != 'show' || !@file_exists($file)) {
279        $_SESSION[DOKU_COOKIE]['bc'] = $crumbs;
280        return $crumbs;
281    }
282
283    // page names
284    $name = noNSorNS($ID);
285    if(useHeading('navigation')) {
286        // get page title
287        $title = p_get_first_heading($ID, METADATA_RENDER_USING_SIMPLE_CACHE);
288        if($title) {
289            $name = $title;
290        }
291    }
292
293    //remove ID from array
294    if(isset($crumbs[$ID])) {
295        unset($crumbs[$ID]);
296    }
297
298    //add to array
299    $crumbs[$ID] = $name;
300    //reduce size
301    while(count($crumbs) > $conf['breadcrumbs']) {
302        array_shift($crumbs);
303    }
304    //save to session
305    $_SESSION[DOKU_COOKIE]['bc'] = $crumbs;
306    return $crumbs;
307}
308
309/**
310 * Filter for page IDs
311 *
312 * This is run on a ID before it is outputted somewhere
313 * currently used to replace the colon with something else
314 * on Windows systems and to have proper URL encoding
315 *
316 * Urlencoding is ommitted when the second parameter is false
317 *
318 * @author Andreas Gohr <andi@splitbrain.org>
319 */
320function idfilter($id, $ue = true) {
321    global $conf;
322    if($conf['useslash'] && $conf['userewrite']) {
323        $id = strtr($id, ':', '/');
324    } elseif(strtoupper(substr(PHP_OS, 0, 3)) === 'WIN' &&
325        $conf['userewrite']
326    ) {
327        $id = strtr($id, ':', ';');
328    }
329    if($ue) {
330        $id = rawurlencode($id);
331        $id = str_replace('%3A', ':', $id); //keep as colon
332        $id = str_replace('%2F', '/', $id); //keep as slash
333    }
334    return $id;
335}
336
337/**
338 * This builds a link to a wikipage
339 *
340 * It handles URL rewriting and adds additional parameter if
341 * given in $more
342 *
343 * @author Andreas Gohr <andi@splitbrain.org>
344 */
345function wl($id = '', $urlParameters = '', $absolute = false, $separator = '&amp;') {
346    global $conf;
347    if(is_array($urlParameters)) {
348        $urlParameters = buildURLparams($urlParameters, $separator);
349    } else {
350        $urlParameters = str_replace(',', $separator, $urlParameters);
351    }
352    if($id === '') {
353        $id = $conf['start'];
354    }
355    $id = idfilter($id);
356    if($absolute) {
357        $xlink = DOKU_URL;
358    } else {
359        $xlink = DOKU_BASE;
360    }
361
362    if($conf['userewrite'] == 2) {
363        $xlink .= DOKU_SCRIPT.'/'.$id;
364        if($urlParameters) $xlink .= '?'.$urlParameters;
365    } elseif($conf['userewrite']) {
366        $xlink .= $id;
367        if($urlParameters) $xlink .= '?'.$urlParameters;
368    } elseif($id) {
369        $xlink .= DOKU_SCRIPT.'?id='.$id;
370        if($urlParameters) $xlink .= $separator.$urlParameters;
371    } else {
372        $xlink .= DOKU_SCRIPT;
373        if($urlParameters) $xlink .= '?'.$urlParameters;
374    }
375
376    return $xlink;
377}
378
379/**
380 * This builds a link to an alternate page format
381 *
382 * Handles URL rewriting if enabled. Follows the style of wl().
383 *
384 * @author Ben Coburn <btcoburn@silicodon.net>
385 */
386function exportlink($id = '', $format = 'raw', $more = '', $abs = false, $sep = '&amp;') {
387    global $conf;
388    if(is_array($more)) {
389        $more = buildURLparams($more, $sep);
390    } else {
391        $more = str_replace(',', $sep, $more);
392    }
393
394    $format = rawurlencode($format);
395    $id     = idfilter($id);
396    if($abs) {
397        $xlink = DOKU_URL;
398    } else {
399        $xlink = DOKU_BASE;
400    }
401
402    if($conf['userewrite'] == 2) {
403        $xlink .= DOKU_SCRIPT.'/'.$id.'?do=export_'.$format;
404        if($more) $xlink .= $sep.$more;
405    } elseif($conf['userewrite'] == 1) {
406        $xlink .= '_export/'.$format.'/'.$id;
407        if($more) $xlink .= '?'.$more;
408    } else {
409        $xlink .= DOKU_SCRIPT.'?do=export_'.$format.$sep.'id='.$id;
410        if($more) $xlink .= $sep.$more;
411    }
412
413    return $xlink;
414}
415
416/**
417 * Build a link to a media file
418 *
419 * Will return a link to the detail page if $direct is false
420 *
421 * The $more parameter should always be given as array, the function then
422 * will strip default parameters to produce even cleaner URLs
423 *
424 * @param string  $id     the media file id or URL
425 * @param mixed   $more   string or array with additional parameters
426 * @param bool    $direct link to detail page if false
427 * @param string  $sep    URL parameter separator
428 * @param bool    $abs    Create an absolute URL
429 * @return string
430 */
431function ml($id = '', $more = '', $direct = true, $sep = '&amp;', $abs = false) {
432    global $conf;
433    if(is_array($more)) {
434        // strip defaults for shorter URLs
435        if(isset($more['cache']) && $more['cache'] == 'cache') unset($more['cache']);
436        if(!$more['w']) unset($more['w']);
437        if(!$more['h']) unset($more['h']);
438        if(isset($more['id']) && $direct) unset($more['id']);
439        $more = buildURLparams($more, $sep);
440    } else {
441        $more = str_replace('cache=cache', '', $more); //skip default
442        $more = str_replace(',,', ',', $more);
443        $more = str_replace(',', $sep, $more);
444    }
445
446    if($abs) {
447        $xlink = DOKU_URL;
448    } else {
449        $xlink = DOKU_BASE;
450    }
451
452    // external URLs are always direct without rewriting
453    if(preg_match('#^(https?|ftp)://#i', $id)) {
454        $xlink .= 'lib/exe/fetch.php';
455        // add hash:
456        $xlink .= '?hash='.substr(md5(auth_cookiesalt().$id), 0, 6);
457        if($more) {
458            $xlink .= $sep.$more;
459            $xlink .= $sep.'media='.rawurlencode($id);
460        } else {
461            $xlink .= $sep.'media='.rawurlencode($id);
462        }
463        return $xlink;
464    }
465
466    $id = idfilter($id);
467
468    // decide on scriptname
469    if($direct) {
470        if($conf['userewrite'] == 1) {
471            $script = '_media';
472        } else {
473            $script = 'lib/exe/fetch.php';
474        }
475    } else {
476        if($conf['userewrite'] == 1) {
477            $script = '_detail';
478        } else {
479            $script = 'lib/exe/detail.php';
480        }
481    }
482
483    // build URL based on rewrite mode
484    if($conf['userewrite']) {
485        $xlink .= $script.'/'.$id;
486        if($more) $xlink .= '?'.$more;
487    } else {
488        if($more) {
489            $xlink .= $script.'?'.$more;
490            $xlink .= $sep.'media='.$id;
491        } else {
492            $xlink .= $script.'?media='.$id;
493        }
494    }
495
496    return $xlink;
497}
498
499/**
500 * Returns the URL to the DokuWiki base script
501 *
502 * Consider using wl() instead, unless you absoutely need the doku.php endpoint
503 *
504 * @author Andreas Gohr <andi@splitbrain.org>
505 */
506function script() {
507    return DOKU_BASE.DOKU_SCRIPT;
508}
509
510/**
511 * Spamcheck against wordlist
512 *
513 * Checks the wikitext against a list of blocked expressions
514 * returns true if the text contains any bad words
515 *
516 * Triggers COMMON_WORDBLOCK_BLOCKED
517 *
518 *  Action Plugins can use this event to inspect the blocked data
519 *  and gain information about the user who was blocked.
520 *
521 *  Event data:
522 *    data['matches']  - array of matches
523 *    data['userinfo'] - information about the blocked user
524 *      [ip]           - ip address
525 *      [user]         - username (if logged in)
526 *      [mail]         - mail address (if logged in)
527 *      [name]         - real name (if logged in)
528 *
529 * @author Andreas Gohr <andi@splitbrain.org>
530 * @author Michael Klier <chi@chimeric.de>
531 * @param  string $text - optional text to check, if not given the globals are used
532 * @return bool         - true if a spam word was found
533 */
534function checkwordblock($text = '') {
535    global $TEXT;
536    global $PRE;
537    global $SUF;
538    global $conf;
539    global $INFO;
540
541    if(!$conf['usewordblock']) return false;
542
543    if(!$text) $text = "$PRE $TEXT $SUF";
544
545    // we prepare the text a tiny bit to prevent spammers circumventing URL checks
546    $text = preg_replace('!(\b)(www\.[\w.:?\-;,]+?\.[\w.:?\-;,]+?[\w/\#~:.?+=&%@\!\-.:?\-;,]+?)([.:?\-;,]*[^\w/\#~:.?+=&%@\!\-.:?\-;,])!i', '\1http://\2 \2\3', $text);
547
548    $wordblocks = getWordblocks();
549    // how many lines to read at once (to work around some PCRE limits)
550    if(version_compare(phpversion(), '4.3.0', '<')) {
551        // old versions of PCRE define a maximum of parenthesises even if no
552        // backreferences are used - the maximum is 99
553        // this is very bad performancewise and may even be too high still
554        $chunksize = 40;
555    } else {
556        // read file in chunks of 200 - this should work around the
557        // MAX_PATTERN_SIZE in modern PCRE
558        $chunksize = 200;
559    }
560    while($blocks = array_splice($wordblocks, 0, $chunksize)) {
561        $re = array();
562        // build regexp from blocks
563        foreach($blocks as $block) {
564            $block = preg_replace('/#.*$/', '', $block);
565            $block = trim($block);
566            if(empty($block)) continue;
567            $re[] = $block;
568        }
569        if(count($re) && preg_match('#('.join('|', $re).')#si', $text, $matches)) {
570            // prepare event data
571            $data['matches']        = $matches;
572            $data['userinfo']['ip'] = $_SERVER['REMOTE_ADDR'];
573            if($_SERVER['REMOTE_USER']) {
574                $data['userinfo']['user'] = $_SERVER['REMOTE_USER'];
575                $data['userinfo']['name'] = $INFO['userinfo']['name'];
576                $data['userinfo']['mail'] = $INFO['userinfo']['mail'];
577            }
578            $callback = create_function('', 'return true;');
579            return trigger_event('COMMON_WORDBLOCK_BLOCKED', $data, $callback, true);
580        }
581    }
582    return false;
583}
584
585/**
586 * Return the IP of the client
587 *
588 * Honours X-Forwarded-For and X-Real-IP Proxy Headers
589 *
590 * It returns a comma separated list of IPs if the above mentioned
591 * headers are set. If the single parameter is set, it tries to return
592 * a routable public address, prefering the ones suplied in the X
593 * headers
594 *
595 * @author Andreas Gohr <andi@splitbrain.org>
596 * @param  boolean $single If set only a single IP is returned
597 * @return string
598 */
599function clientIP($single = false) {
600    $ip   = array();
601    $ip[] = $_SERVER['REMOTE_ADDR'];
602    if(!empty($_SERVER['HTTP_X_FORWARDED_FOR']))
603        $ip = array_merge($ip, explode(',', str_replace(' ', '', $_SERVER['HTTP_X_FORWARDED_FOR'])));
604    if(!empty($_SERVER['HTTP_X_REAL_IP']))
605        $ip = array_merge($ip, explode(',', str_replace(' ', '', $_SERVER['HTTP_X_REAL_IP'])));
606
607    // some IPv4/v6 regexps borrowed from Feyd
608    // see: http://forums.devnetwork.net/viewtopic.php?f=38&t=53479
609    $dec_octet   = '(?:25[0-5]|2[0-4]\d|1\d\d|[1-9]\d|[0-9])';
610    $hex_digit   = '[A-Fa-f0-9]';
611    $h16         = "{$hex_digit}{1,4}";
612    $IPv4Address = "$dec_octet\\.$dec_octet\\.$dec_octet\\.$dec_octet";
613    $ls32        = "(?:$h16:$h16|$IPv4Address)";
614    $IPv6Address =
615        "(?:(?:{$IPv4Address})|(?:".
616            "(?:$h16:){6}$ls32".
617            "|::(?:$h16:){5}$ls32".
618            "|(?:$h16)?::(?:$h16:){4}$ls32".
619            "|(?:(?:$h16:){0,1}$h16)?::(?:$h16:){3}$ls32".
620            "|(?:(?:$h16:){0,2}$h16)?::(?:$h16:){2}$ls32".
621            "|(?:(?:$h16:){0,3}$h16)?::(?:$h16:){1}$ls32".
622            "|(?:(?:$h16:){0,4}$h16)?::$ls32".
623            "|(?:(?:$h16:){0,5}$h16)?::$h16".
624            "|(?:(?:$h16:){0,6}$h16)?::".
625            ")(?:\\/(?:12[0-8]|1[0-1][0-9]|[1-9][0-9]|[0-9]))?)";
626
627    // remove any non-IP stuff
628    $cnt   = count($ip);
629    $match = array();
630    for($i = 0; $i < $cnt; $i++) {
631        if(preg_match("/^$IPv4Address$/", $ip[$i], $match) || preg_match("/^$IPv6Address$/", $ip[$i], $match)) {
632            $ip[$i] = $match[0];
633        } else {
634            $ip[$i] = '';
635        }
636        if(empty($ip[$i])) unset($ip[$i]);
637    }
638    $ip = array_values(array_unique($ip));
639    if(!$ip[0]) $ip[0] = '0.0.0.0'; // for some strange reason we don't have a IP
640
641    if(!$single) return join(',', $ip);
642
643    // decide which IP to use, trying to avoid local addresses
644    $ip = array_reverse($ip);
645    foreach($ip as $i) {
646        if(preg_match('/^(::1|[fF][eE]80:|127\.|10\.|192\.168\.|172\.((1[6-9])|(2[0-9])|(3[0-1]))\.)/', $i)) {
647            continue;
648        } else {
649            return $i;
650        }
651    }
652    // still here? just use the first (last) address
653    return $ip[0];
654}
655
656/**
657 * Check if the browser is on a mobile device
658 *
659 * Adapted from the example code at url below
660 *
661 * @link http://www.brainhandles.com/2007/10/15/detecting-mobile-browsers/#code
662 */
663function clientismobile() {
664
665    if(isset($_SERVER['HTTP_X_WAP_PROFILE'])) return true;
666
667    if(preg_match('/wap\.|\.wap/i', $_SERVER['HTTP_ACCEPT'])) return true;
668
669    if(!isset($_SERVER['HTTP_USER_AGENT'])) return false;
670
671    $uamatches = 'midp|j2me|avantg|docomo|novarra|palmos|palmsource|240x320|opwv|chtml|pda|windows ce|mmp\/|blackberry|mib\/|symbian|wireless|nokia|hand|mobi|phone|cdm|up\.b|audio|SIE\-|SEC\-|samsung|HTC|mot\-|mitsu|sagem|sony|alcatel|lg|erics|vx|NEC|philips|mmm|xx|panasonic|sharp|wap|sch|rover|pocket|benq|java|pt|pg|vox|amoi|bird|compal|kg|voda|sany|kdd|dbt|sendo|sgh|gradi|jb|\d\d\di|moto';
672
673    if(preg_match("/$uamatches/i", $_SERVER['HTTP_USER_AGENT'])) return true;
674
675    return false;
676}
677
678/**
679 * Convert one or more comma separated IPs to hostnames
680 *
681 * If $conf['dnslookups'] is disabled it simply returns the input string
682 *
683 * @author Glen Harris <astfgl@iamnota.org>
684 * @param  string $ips comma separated list of IP addresses
685 * @return string a comma separated list of hostnames
686 */
687function gethostsbyaddrs($ips) {
688    global $conf;
689    if(!$conf['dnslookups']) return $ips;
690
691    $hosts = array();
692    $ips   = explode(',', $ips);
693
694    if(is_array($ips)) {
695        foreach($ips as $ip) {
696            $hosts[] = gethostbyaddr(trim($ip));
697        }
698        return join(',', $hosts);
699    } else {
700        return gethostbyaddr(trim($ips));
701    }
702}
703
704/**
705 * Checks if a given page is currently locked.
706 *
707 * removes stale lockfiles
708 *
709 * @author Andreas Gohr <andi@splitbrain.org>
710 */
711function checklock($id) {
712    global $conf;
713    $lock = wikiLockFN($id);
714
715    //no lockfile
716    if(!@file_exists($lock)) return false;
717
718    //lockfile expired
719    if((time() - filemtime($lock)) > $conf['locktime']) {
720        @unlink($lock);
721        return false;
722    }
723
724    //my own lock
725    list($ip, $session) = explode("\n", io_readFile($lock));
726    if($ip == $_SERVER['REMOTE_USER'] || $ip == clientIP() || $session == session_id()) {
727        return false;
728    }
729
730    return $ip;
731}
732
733/**
734 * Lock a page for editing
735 *
736 * @author Andreas Gohr <andi@splitbrain.org>
737 */
738function lock($id) {
739    global $conf;
740
741    if($conf['locktime'] == 0) {
742        return;
743    }
744
745    $lock = wikiLockFN($id);
746    if($_SERVER['REMOTE_USER']) {
747        io_saveFile($lock, $_SERVER['REMOTE_USER']);
748    } else {
749        io_saveFile($lock, clientIP()."\n".session_id());
750    }
751}
752
753/**
754 * Unlock a page if it was locked by the user
755 *
756 * @author Andreas Gohr <andi@splitbrain.org>
757 * @param string $id page id to unlock
758 * @return bool true if a lock was removed
759 */
760function unlock($id) {
761    $lock = wikiLockFN($id);
762    if(@file_exists($lock)) {
763        list($ip, $session) = explode("\n", io_readFile($lock));
764        if($ip == $_SERVER['REMOTE_USER'] || $ip == clientIP() || $session == session_id()) {
765            @unlink($lock);
766            return true;
767        }
768    }
769    return false;
770}
771
772/**
773 * convert line ending to unix format
774 *
775 * @see    formText() for 2crlf conversion
776 * @author Andreas Gohr <andi@splitbrain.org>
777 */
778function cleanText($text) {
779    $text = preg_replace("/(\015\012)|(\015)/", "\012", $text);
780    return $text;
781}
782
783/**
784 * Prepares text for print in Webforms by encoding special chars.
785 * It also converts line endings to Windows format which is
786 * pseudo standard for webforms.
787 *
788 * @see    cleanText() for 2unix conversion
789 * @author Andreas Gohr <andi@splitbrain.org>
790 */
791function formText($text) {
792    $text = str_replace("\012", "\015\012", $text);
793    return htmlspecialchars($text);
794}
795
796/**
797 * Returns the specified local text in raw format
798 *
799 * @author Andreas Gohr <andi@splitbrain.org>
800 */
801function rawLocale($id, $ext = 'txt') {
802    return io_readFile(localeFN($id, $ext));
803}
804
805/**
806 * Returns the raw WikiText
807 *
808 * @author Andreas Gohr <andi@splitbrain.org>
809 */
810function rawWiki($id, $rev = '') {
811    return io_readWikiPage(wikiFN($id, $rev), $id, $rev);
812}
813
814/**
815 * Returns the pagetemplate contents for the ID's namespace
816 *
817 * @triggers COMMON_PAGETPL_LOAD
818 * @author Andreas Gohr <andi@splitbrain.org>
819 */
820function pageTemplate($id) {
821    global $conf;
822
823    if(is_array($id)) $id = $id[0];
824
825    // prepare initial event data
826    $data = array(
827        'id'        => $id, // the id of the page to be created
828        'tpl'       => '', // the text used as template
829        'tplfile'   => '', // the file above text was/should be loaded from
830        'doreplace' => true // should wildcard replacements be done on the text?
831    );
832
833    $evt = new Doku_Event('COMMON_PAGETPL_LOAD', $data);
834    if($evt->advise_before(true)) {
835        // the before event might have loaded the content already
836        if(empty($data['tpl'])) {
837            // if the before event did not set a template file, try to find one
838            if(empty($data['tplfile'])) {
839                $path = dirname(wikiFN($id));
840                if(@file_exists($path.'/_template.txt')) {
841                    $data['tplfile'] = $path.'/_template.txt';
842                } else {
843                    // search upper namespaces for templates
844                    $len = strlen(rtrim($conf['datadir'], '/'));
845                    while(strlen($path) >= $len) {
846                        if(@file_exists($path.'/__template.txt')) {
847                            $data['tplfile'] = $path.'/__template.txt';
848                            break;
849                        }
850                        $path = substr($path, 0, strrpos($path, '/'));
851                    }
852                }
853            }
854            // load the content
855            $data['tpl'] = io_readFile($data['tplfile']);
856        }
857        if($data['doreplace']) parsePageTemplate($data);
858    }
859    $evt->advise_after();
860    unset($evt);
861
862    return $data['tpl'];
863}
864
865/**
866 * Performs common page template replacements
867 * This works on data from COMMON_PAGETPL_LOAD
868 *
869 * @author Andreas Gohr <andi@splitbrain.org>
870 */
871function parsePageTemplate(&$data) {
872    /**
873     * @var string $id        the id of the page to be created
874     * @var string $tpl       the text used as template
875     * @var string $tplfile   the file above text was/should be loaded from
876     * @var bool   $doreplace should wildcard replacements be done on the text?
877     */
878    extract($data);
879
880    global $USERINFO;
881    global $conf;
882
883    // replace placeholders
884    $file = noNS($id);
885    $page = strtr($file, $conf['sepchar'], ' ');
886
887    $tpl = str_replace(
888        array(
889             '@ID@',
890             '@NS@',
891             '@FILE@',
892             '@!FILE@',
893             '@!FILE!@',
894             '@PAGE@',
895             '@!PAGE@',
896             '@!!PAGE@',
897             '@!PAGE!@',
898             '@USER@',
899             '@NAME@',
900             '@MAIL@',
901             '@DATE@',
902        ),
903        array(
904             $id,
905             getNS($id),
906             $file,
907             utf8_ucfirst($file),
908             utf8_strtoupper($file),
909             $page,
910             utf8_ucfirst($page),
911             utf8_ucwords($page),
912             utf8_strtoupper($page),
913             $_SERVER['REMOTE_USER'],
914             $USERINFO['name'],
915             $USERINFO['mail'],
916             $conf['dformat'],
917        ), $tpl
918    );
919
920    // we need the callback to work around strftime's char limit
921    $tpl         = preg_replace_callback('/%./', create_function('$m', 'return strftime($m[0]);'), $tpl);
922    $data['tpl'] = $tpl;
923    return $tpl;
924}
925
926/**
927 * Returns the raw Wiki Text in three slices.
928 *
929 * The range parameter needs to have the form "from-to"
930 * and gives the range of the section in bytes - no
931 * UTF-8 awareness is needed.
932 * The returned order is prefix, section and suffix.
933 *
934 * @author Andreas Gohr <andi@splitbrain.org>
935 */
936function rawWikiSlices($range, $id, $rev = '') {
937    $text = io_readWikiPage(wikiFN($id, $rev), $id, $rev);
938
939    // Parse range
940    list($from, $to) = explode('-', $range, 2);
941    // Make range zero-based, use defaults if marker is missing
942    $from = !$from ? 0 : ($from - 1);
943    $to   = !$to ? strlen($text) : ($to - 1);
944
945    $slices[0] = substr($text, 0, $from);
946    $slices[1] = substr($text, $from, $to - $from);
947    $slices[2] = substr($text, $to);
948    return $slices;
949}
950
951/**
952 * Joins wiki text slices
953 *
954 * function to join the text slices.
955 * When the pretty parameter is set to true it adds additional empty
956 * lines between sections if needed (used on saving).
957 *
958 * @author Andreas Gohr <andi@splitbrain.org>
959 */
960function con($pre, $text, $suf, $pretty = false) {
961    if($pretty) {
962        if($pre !== '' && substr($pre, -1) !== "\n" &&
963            substr($text, 0, 1) !== "\n"
964        ) {
965            $pre .= "\n";
966        }
967        if($suf !== '' && substr($text, -1) !== "\n" &&
968            substr($suf, 0, 1) !== "\n"
969        ) {
970            $text .= "\n";
971        }
972    }
973
974    return $pre.$text.$suf;
975}
976
977/**
978 * Saves a wikitext by calling io_writeWikiPage.
979 * Also directs changelog and attic updates.
980 *
981 * @author Andreas Gohr <andi@splitbrain.org>
982 * @author Ben Coburn <btcoburn@silicodon.net>
983 */
984function saveWikiText($id, $text, $summary, $minor = false) {
985    /* Note to developers:
986       This code is subtle and delicate. Test the behavior of
987       the attic and changelog with dokuwiki and external edits
988       after any changes. External edits change the wiki page
989       directly without using php or dokuwiki.
990     */
991    global $conf;
992    global $lang;
993    global $REV;
994    // ignore if no changes were made
995    if($text == rawWiki($id, '')) {
996        return;
997    }
998
999    $file        = wikiFN($id);
1000    $old         = @filemtime($file); // from page
1001    $wasRemoved  = (trim($text) == ''); // check for empty or whitespace only
1002    $wasCreated  = !@file_exists($file);
1003    $wasReverted = ($REV == true);
1004    $newRev      = false;
1005    $oldRev      = getRevisions($id, -1, 1, 1024); // from changelog
1006    $oldRev      = (int) (empty($oldRev) ? 0 : $oldRev[0]);
1007    if(!@file_exists(wikiFN($id, $old)) && @file_exists($file) && $old >= $oldRev) {
1008        // add old revision to the attic if missing
1009        saveOldRevision($id);
1010        // add a changelog entry if this edit came from outside dokuwiki
1011        if($old > $oldRev) {
1012            addLogEntry($old, $id, DOKU_CHANGE_TYPE_EDIT, $lang['external_edit'], '', array('ExternalEdit'=> true));
1013            // remove soon to be stale instructions
1014            $cache = new cache_instructions($id, $file);
1015            $cache->removeCache();
1016        }
1017    }
1018
1019    if($wasRemoved) {
1020        // Send "update" event with empty data, so plugins can react to page deletion
1021        $data = array(array($file, '', false), getNS($id), noNS($id), false);
1022        trigger_event('IO_WIKIPAGE_WRITE', $data);
1023        // pre-save deleted revision
1024        @touch($file);
1025        clearstatcache();
1026        $newRev = saveOldRevision($id);
1027        // remove empty file
1028        @unlink($file);
1029        // don't remove old meta info as it should be saved, plugins can use IO_WIKIPAGE_WRITE for removing their metadata...
1030        // purge non-persistant meta data
1031        p_purge_metadata($id);
1032        $del = true;
1033        // autoset summary on deletion
1034        if(empty($summary)) $summary = $lang['deleted'];
1035        // remove empty namespaces
1036        io_sweepNS($id, 'datadir');
1037        io_sweepNS($id, 'mediadir');
1038    } else {
1039        // save file (namespace dir is created in io_writeWikiPage)
1040        io_writeWikiPage($file, $text, $id);
1041        // pre-save the revision, to keep the attic in sync
1042        $newRev = saveOldRevision($id);
1043        $del    = false;
1044    }
1045
1046    // select changelog line type
1047    $extra = '';
1048    $type  = DOKU_CHANGE_TYPE_EDIT;
1049    if($wasReverted) {
1050        $type  = DOKU_CHANGE_TYPE_REVERT;
1051        $extra = $REV;
1052    } else if($wasCreated) {
1053        $type = DOKU_CHANGE_TYPE_CREATE;
1054    } else if($wasRemoved) {
1055        $type = DOKU_CHANGE_TYPE_DELETE;
1056    } else if($minor && $conf['useacl'] && $_SERVER['REMOTE_USER']) {
1057        $type = DOKU_CHANGE_TYPE_MINOR_EDIT;
1058    } //minor edits only for logged in users
1059
1060    addLogEntry($newRev, $id, $type, $summary, $extra);
1061    // send notify mails
1062    notify($id, 'admin', $old, $summary, $minor);
1063    notify($id, 'subscribers', $old, $summary, $minor);
1064
1065    // update the purgefile (timestamp of the last time anything within the wiki was changed)
1066    io_saveFile($conf['cachedir'].'/purgefile', time());
1067
1068    // if useheading is enabled, purge the cache of all linking pages
1069    if(useHeading('content')) {
1070        $pages = ft_backlinks($id);
1071        foreach($pages as $page) {
1072            $cache = new cache_renderer($page, wikiFN($page), 'xhtml');
1073            $cache->removeCache();
1074        }
1075    }
1076}
1077
1078/**
1079 * moves the current version to the attic and returns its
1080 * revision date
1081 *
1082 * @author Andreas Gohr <andi@splitbrain.org>
1083 */
1084function saveOldRevision($id) {
1085    global $conf;
1086    $oldf = wikiFN($id);
1087    if(!@file_exists($oldf)) return '';
1088    $date = filemtime($oldf);
1089    $newf = wikiFN($id, $date);
1090    io_writeWikiPage($newf, rawWiki($id), $id, $date);
1091    return $date;
1092}
1093
1094/**
1095 * Sends a notify mail on page change or registration
1096 *
1097 * @param string     $id       The changed page
1098 * @param string     $who      Who to notify (admin|subscribers|register)
1099 * @param int|string $rev Old page revision
1100 * @param string     $summary  What changed
1101 * @param boolean    $minor    Is this a minor edit?
1102 * @param array      $replace  Additional string substitutions, @KEY@ to be replaced by value
1103 *
1104 * @return bool
1105 * @author Andreas Gohr <andi@splitbrain.org>
1106 */
1107function notify($id, $who, $rev = '', $summary = '', $minor = false, $replace = array()) {
1108    global $conf;
1109
1110    // decide if there is something to do, eg. whom to mail
1111    if($who == 'admin') {
1112        if(empty($conf['notify'])) return false; //notify enabled?
1113        $tpl = 'mailtext';
1114        $to  = $conf['notify'];
1115    } elseif($who == 'subscribers') {
1116        if(!actionOK('subscribe')) return false; //subscribers enabled?
1117        if($conf['useacl'] && $_SERVER['REMOTE_USER'] && $minor) return false; //skip minors
1118        $data = array('id' => $id, 'addresslist' => '', 'self' => false);
1119        trigger_event(
1120            'COMMON_NOTIFY_ADDRESSLIST', $data,
1121            array(new Subscription(), 'notifyaddresses')
1122        );
1123        $to = $data['addresslist'];
1124        if(empty($to)) return false;
1125        $tpl = 'subscr_single';
1126    } else {
1127        return false; //just to be safe
1128    }
1129
1130    // prepare content
1131    $subscription = new Subscription();
1132    return $subscription->send_diff($to, $tpl, $id, $rev, $summary);
1133}
1134
1135/**
1136 * extracts the query from a search engine referrer
1137 *
1138 * @author Andreas Gohr <andi@splitbrain.org>
1139 * @author Todd Augsburger <todd@rollerorgans.com>
1140 */
1141function getGoogleQuery() {
1142    if(!isset($_SERVER['HTTP_REFERER'])) {
1143        return '';
1144    }
1145    $url = parse_url($_SERVER['HTTP_REFERER']);
1146
1147    // only handle common SEs
1148    if(!preg_match('/(google|bing|yahoo|ask|duckduckgo|babylon|aol|yandex)/',$url['host'])) return '';
1149
1150    $query = array();
1151    // temporary workaround against PHP bug #49733
1152    // see http://bugs.php.net/bug.php?id=49733
1153    if(UTF8_MBSTRING) $enc = mb_internal_encoding();
1154    parse_str($url['query'], $query);
1155    if(UTF8_MBSTRING) mb_internal_encoding($enc);
1156
1157    $q = '';
1158    if(isset($query['q'])){
1159        $q = $query['q'];
1160    }elseif(isset($query['p'])){
1161        $q = $query['p'];
1162    }elseif(isset($query['query'])){
1163        $q = $query['query'];
1164    }
1165    $q = trim($q);
1166
1167    if(!$q) return '';
1168    $q = preg_split('/[\s\'"\\\\`()\]\[?:!\.{};,#+*<>\\/]+/', $q, -1, PREG_SPLIT_NO_EMPTY);
1169    return $q;
1170}
1171
1172/**
1173 * Try to set correct locale
1174 *
1175 * @deprecated No longer used
1176 * @author     Andreas Gohr <andi@splitbrain.org>
1177 */
1178function setCorrectLocale() {
1179    global $conf;
1180    global $lang;
1181
1182    $enc = strtoupper($lang['encoding']);
1183    foreach($lang['locales'] as $loc) {
1184        //try locale
1185        if(@setlocale(LC_ALL, $loc)) return;
1186        //try loceale with encoding
1187        if(@setlocale(LC_ALL, "$loc.$enc")) return;
1188    }
1189    //still here? try to set from environment
1190    @setlocale(LC_ALL, "");
1191}
1192
1193/**
1194 * Return the human readable size of a file
1195 *
1196 * @param       int    $size   A file size
1197 * @param       int    $dec    A number of decimal places
1198 * @author      Martin Benjamin <b.martin@cybernet.ch>
1199 * @author      Aidan Lister <aidan@php.net>
1200 * @version     1.0.0
1201 */
1202function filesize_h($size, $dec = 1) {
1203    $sizes = array('B', 'KB', 'MB', 'GB');
1204    $count = count($sizes);
1205    $i     = 0;
1206
1207    while($size >= 1024 && ($i < $count - 1)) {
1208        $size /= 1024;
1209        $i++;
1210    }
1211
1212    return round($size, $dec).' '.$sizes[$i];
1213}
1214
1215/**
1216 * Return the given timestamp as human readable, fuzzy age
1217 *
1218 * @author Andreas Gohr <gohr@cosmocode.de>
1219 */
1220function datetime_h($dt) {
1221    global $lang;
1222
1223    $ago = time() - $dt;
1224    if($ago > 24 * 60 * 60 * 30 * 12 * 2) {
1225        return sprintf($lang['years'], round($ago / (24 * 60 * 60 * 30 * 12)));
1226    }
1227    if($ago > 24 * 60 * 60 * 30 * 2) {
1228        return sprintf($lang['months'], round($ago / (24 * 60 * 60 * 30)));
1229    }
1230    if($ago > 24 * 60 * 60 * 7 * 2) {
1231        return sprintf($lang['weeks'], round($ago / (24 * 60 * 60 * 7)));
1232    }
1233    if($ago > 24 * 60 * 60 * 2) {
1234        return sprintf($lang['days'], round($ago / (24 * 60 * 60)));
1235    }
1236    if($ago > 60 * 60 * 2) {
1237        return sprintf($lang['hours'], round($ago / (60 * 60)));
1238    }
1239    if($ago > 60 * 2) {
1240        return sprintf($lang['minutes'], round($ago / (60)));
1241    }
1242    return sprintf($lang['seconds'], $ago);
1243}
1244
1245/**
1246 * Wraps around strftime but provides support for fuzzy dates
1247 *
1248 * The format default to $conf['dformat']. It is passed to
1249 * strftime - %f can be used to get the value from datetime_h()
1250 *
1251 * @see datetime_h
1252 * @author Andreas Gohr <gohr@cosmocode.de>
1253 */
1254function dformat($dt = null, $format = '') {
1255    global $conf;
1256
1257    if(is_null($dt)) $dt = time();
1258    $dt = (int) $dt;
1259    if(!$format) $format = $conf['dformat'];
1260
1261    $format = str_replace('%f', datetime_h($dt), $format);
1262    return strftime($format, $dt);
1263}
1264
1265/**
1266 * Formats a timestamp as ISO 8601 date
1267 *
1268 * @author <ungu at terong dot com>
1269 * @link http://www.php.net/manual/en/function.date.php#54072
1270 * @param int $int_date: current date in UNIX timestamp
1271 * @return string
1272 */
1273function date_iso8601($int_date) {
1274    $date_mod     = date('Y-m-d\TH:i:s', $int_date);
1275    $pre_timezone = date('O', $int_date);
1276    $time_zone    = substr($pre_timezone, 0, 3).":".substr($pre_timezone, 3, 2);
1277    $date_mod .= $time_zone;
1278    return $date_mod;
1279}
1280
1281/**
1282 * return an obfuscated email address in line with $conf['mailguard'] setting
1283 *
1284 * @author Harry Fuecks <hfuecks@gmail.com>
1285 * @author Christopher Smith <chris@jalakai.co.uk>
1286 */
1287function obfuscate($email) {
1288    global $conf;
1289
1290    switch($conf['mailguard']) {
1291        case 'visible' :
1292            $obfuscate = array('@' => ' [at] ', '.' => ' [dot] ', '-' => ' [dash] ');
1293            return strtr($email, $obfuscate);
1294
1295        case 'hex' :
1296            $encode = '';
1297            $len    = strlen($email);
1298            for($x = 0; $x < $len; $x++) {
1299                $encode .= '&#x'.bin2hex($email{$x}).';';
1300            }
1301            return $encode;
1302
1303        case 'none' :
1304        default :
1305            return $email;
1306    }
1307}
1308
1309/**
1310 * Removes quoting backslashes
1311 *
1312 * @author Andreas Gohr <andi@splitbrain.org>
1313 */
1314function unslash($string, $char = "'") {
1315    return str_replace('\\'.$char, $char, $string);
1316}
1317
1318/**
1319 * Convert php.ini shorthands to byte
1320 *
1321 * @author <gilthans dot NO dot SPAM at gmail dot com>
1322 * @link   http://de3.php.net/manual/en/ini.core.php#79564
1323 */
1324function php_to_byte($v) {
1325    $l   = substr($v, -1);
1326    $ret = substr($v, 0, -1);
1327    switch(strtoupper($l)) {
1328        case 'P':
1329            $ret *= 1024;
1330        case 'T':
1331            $ret *= 1024;
1332        case 'G':
1333            $ret *= 1024;
1334        case 'M':
1335            $ret *= 1024;
1336        case 'K':
1337            $ret *= 1024;
1338            break;
1339        default;
1340            $ret *= 10;
1341            break;
1342    }
1343    return $ret;
1344}
1345
1346/**
1347 * Wrapper around preg_quote adding the default delimiter
1348 */
1349function preg_quote_cb($string) {
1350    return preg_quote($string, '/');
1351}
1352
1353/**
1354 * Shorten a given string by removing data from the middle
1355 *
1356 * You can give the string in two parts, the first part $keep
1357 * will never be shortened. The second part $short will be cut
1358 * in the middle to shorten but only if at least $min chars are
1359 * left to display it. Otherwise it will be left off.
1360 *
1361 * @param string $keep   the part to keep
1362 * @param string $short  the part to shorten
1363 * @param int    $max    maximum chars you want for the whole string
1364 * @param int    $min    minimum number of chars to have left for middle shortening
1365 * @param string $char   the shortening character to use
1366 * @return string
1367 */
1368function shorten($keep, $short, $max, $min = 9, $char = '…') {
1369    $max = $max - utf8_strlen($keep);
1370    if($max < $min) return $keep;
1371    $len = utf8_strlen($short);
1372    if($len <= $max) return $keep.$short;
1373    $half = floor($max / 2);
1374    return $keep.utf8_substr($short, 0, $half - 1).$char.utf8_substr($short, $len - $half);
1375}
1376
1377/**
1378 * Return the users realname or e-mail address for use
1379 * in page footer and recent changes pages
1380 *
1381 * @author Andy Webber <dokuwiki AT andywebber DOT com>
1382 */
1383function editorinfo($username) {
1384    global $conf;
1385    global $auth;
1386
1387    switch($conf['showuseras']) {
1388        case 'username':
1389        case 'email':
1390        case 'email_link':
1391            if($auth) $info = $auth->getUserData($username);
1392            break;
1393        default:
1394            return hsc($username);
1395    }
1396
1397    if(isset($info) && $info) {
1398        switch($conf['showuseras']) {
1399            case 'username':
1400                return hsc($info['name']);
1401            case 'email':
1402                return obfuscate($info['mail']);
1403            case 'email_link':
1404                $mail = obfuscate($info['mail']);
1405                return '<a href="mailto:'.$mail.'">'.$mail.'</a>';
1406            default:
1407                return hsc($username);
1408        }
1409    } else {
1410        return hsc($username);
1411    }
1412}
1413
1414/**
1415 * Returns the path to a image file for the currently chosen license.
1416 * When no image exists, returns an empty string
1417 *
1418 * @author Andreas Gohr <andi@splitbrain.org>
1419 * @param  string $type - type of image 'badge' or 'button'
1420 * @return string
1421 */
1422function license_img($type) {
1423    global $license;
1424    global $conf;
1425    if(!$conf['license']) return '';
1426    if(!is_array($license[$conf['license']])) return '';
1427    $lic   = $license[$conf['license']];
1428    $try   = array();
1429    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.png';
1430    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.gif';
1431    if(substr($conf['license'], 0, 3) == 'cc-') {
1432        $try[] = 'lib/images/license/'.$type.'/cc.png';
1433    }
1434    foreach($try as $src) {
1435        if(@file_exists(DOKU_INC.$src)) return $src;
1436    }
1437    return '';
1438}
1439
1440/**
1441 * Checks if the given amount of memory is available
1442 *
1443 * If the memory_get_usage() function is not available the
1444 * function just assumes $bytes of already allocated memory
1445 *
1446 * @author Filip Oscadal <webmaster@illusionsoftworks.cz>
1447 * @author Andreas Gohr <andi@splitbrain.org>
1448 *
1449 * @param  int $mem  Size of memory you want to allocate in bytes
1450 * @param int  $bytes
1451 * @internal param int $used already allocated memory (see above)
1452 * @return bool
1453 */
1454function is_mem_available($mem, $bytes = 1048576) {
1455    $limit = trim(ini_get('memory_limit'));
1456    if(empty($limit)) return true; // no limit set!
1457
1458    // parse limit to bytes
1459    $limit = php_to_byte($limit);
1460
1461    // get used memory if possible
1462    if(function_exists('memory_get_usage')) {
1463        $used = memory_get_usage();
1464    } else {
1465        $used = $bytes;
1466    }
1467
1468    if($used + $mem > $limit) {
1469        return false;
1470    }
1471
1472    return true;
1473}
1474
1475/**
1476 * Send a HTTP redirect to the browser
1477 *
1478 * Works arround Microsoft IIS cookie sending bug. Exits the script.
1479 *
1480 * @link   http://support.microsoft.com/kb/q176113/
1481 * @author Andreas Gohr <andi@splitbrain.org>
1482 */
1483function send_redirect($url) {
1484    //are there any undisplayed messages? keep them in session for display
1485    global $MSG;
1486    if(isset($MSG) && count($MSG) && !defined('NOSESSION')) {
1487        //reopen session, store data and close session again
1488        @session_start();
1489        $_SESSION[DOKU_COOKIE]['msg'] = $MSG;
1490    }
1491
1492    // always close the session
1493    session_write_close();
1494
1495    // work around IE bug
1496    // http://www.ianhoar.com/2008/11/16/internet-explorer-6-and-redirected-anchor-links/
1497    list($url, $hash) = explode('#', $url);
1498    if($hash) {
1499        if(strpos($url, '?')) {
1500            $url = $url.'&#'.$hash;
1501        } else {
1502            $url = $url.'?&#'.$hash;
1503        }
1504    }
1505
1506    // check if running on IIS < 6 with CGI-PHP
1507    if(isset($_SERVER['SERVER_SOFTWARE']) && isset($_SERVER['GATEWAY_INTERFACE']) &&
1508        (strpos($_SERVER['GATEWAY_INTERFACE'], 'CGI') !== false) &&
1509        (preg_match('|^Microsoft-IIS/(\d)\.\d$|', trim($_SERVER['SERVER_SOFTWARE']), $matches)) &&
1510        $matches[1] < 6
1511    ) {
1512        header('Refresh: 0;url='.$url);
1513    } else {
1514        header('Location: '.$url);
1515    }
1516    exit;
1517}
1518
1519/**
1520 * Validate a value using a set of valid values
1521 *
1522 * This function checks whether a specified value is set and in the array
1523 * $valid_values. If not, the function returns a default value or, if no
1524 * default is specified, throws an exception.
1525 *
1526 * @param string $param        The name of the parameter
1527 * @param array  $valid_values A set of valid values; Optionally a default may
1528 *                             be marked by the key “default”.
1529 * @param array  $array        The array containing the value (typically $_POST
1530 *                             or $_GET)
1531 * @param string $exc          The text of the raised exception
1532 *
1533 * @throws Exception
1534 * @return mixed
1535 * @author Adrian Lang <lang@cosmocode.de>
1536 */
1537function valid_input_set($param, $valid_values, $array, $exc = '') {
1538    if(isset($array[$param]) && in_array($array[$param], $valid_values)) {
1539        return $array[$param];
1540    } elseif(isset($valid_values['default'])) {
1541        return $valid_values['default'];
1542    } else {
1543        throw new Exception($exc);
1544    }
1545}
1546
1547/**
1548 * Read a preference from the DokuWiki cookie
1549 */
1550function get_doku_pref($pref, $default) {
1551    if(strpos($_COOKIE['DOKU_PREFS'], $pref) !== false) {
1552        $parts = explode('#', $_COOKIE['DOKU_PREFS']);
1553        $cnt   = count($parts);
1554        for($i = 0; $i < $cnt; $i += 2) {
1555            if($parts[$i] == $pref) {
1556                return $parts[$i + 1];
1557            }
1558        }
1559    }
1560    return $default;
1561}
1562
1563//Setup VIM: ex: et ts=2 :
1564