xref: /dokuwiki/inc/common.php (revision c1b2e736c1da490219a060dd52104c4f88e70f7e) 
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    $lock = wikiLockFN($id);
736    if($_SERVER['REMOTE_USER']){
737        io_saveFile($lock,$_SERVER['REMOTE_USER']);
738    }else{
739        io_saveFile($lock,clientIP());
740    }
741}
742
743/**
744 * Unlock a page if it was locked by the user
745 *
746 * @author Andreas Gohr <andi@splitbrain.org>
747 * @return bool true if a lock was removed
748 */
749function unlock($id){
750    $lock = wikiLockFN($id);
751    if(@file_exists($lock)){
752        $ip = io_readFile($lock);
753        if( ($ip == clientIP()) || ($ip == $_SERVER['REMOTE_USER']) ){
754            @unlink($lock);
755            return true;
756        }
757    }
758    return false;
759}
760
761/**
762 * convert line ending to unix format
763 *
764 * @see    formText() for 2crlf conversion
765 * @author Andreas Gohr <andi@splitbrain.org>
766 */
767function cleanText($text){
768    $text = preg_replace("/(\015\012)|(\015)/","\012",$text);
769    return $text;
770}
771
772/**
773 * Prepares text for print in Webforms by encoding special chars.
774 * It also converts line endings to Windows format which is
775 * pseudo standard for webforms.
776 *
777 * @see    cleanText() for 2unix conversion
778 * @author Andreas Gohr <andi@splitbrain.org>
779 */
780function formText($text){
781    $text = str_replace("\012","\015\012",$text);
782    return htmlspecialchars($text);
783}
784
785/**
786 * Returns the specified local text in raw format
787 *
788 * @author Andreas Gohr <andi@splitbrain.org>
789 */
790function rawLocale($id){
791    return io_readFile(localeFN($id));
792}
793
794/**
795 * Returns the raw WikiText
796 *
797 * @author Andreas Gohr <andi@splitbrain.org>
798 */
799function rawWiki($id,$rev=''){
800    return io_readWikiPage(wikiFN($id, $rev), $id, $rev);
801}
802
803/**
804 * Returns the pagetemplate contents for the ID's namespace
805 *
806 * @author Andreas Gohr <andi@splitbrain.org>
807 */
808function pageTemplate($data){
809    $id = $data[0];
810    global $conf;
811    global $INFO;
812
813    $path = dirname(wikiFN($id));
814
815    if(@file_exists($path.'/_template.txt')){
816        $tpl = io_readFile($path.'/_template.txt');
817    }else{
818        // search upper namespaces for templates
819        $len = strlen(rtrim($conf['datadir'],'/'));
820        while (strlen($path) >= $len){
821            if(@file_exists($path.'/__template.txt')){
822                $tpl = io_readFile($path.'/__template.txt');
823                break;
824            }
825            $path = substr($path, 0, strrpos($path, '/'));
826        }
827    }
828    if(!$tpl) return '';
829
830    // replace placeholders
831    $file = noNS($id);
832    $page = strtr($file,'_',' ');
833
834    $tpl = str_replace(array(
835                '@ID@',
836                '@NS@',
837                '@FILE@',
838                '@!FILE@',
839                '@!FILE!@',
840                '@PAGE@',
841                '@!PAGE@',
842                '@!!PAGE@',
843                '@!PAGE!@',
844                '@USER@',
845                '@NAME@',
846                '@MAIL@',
847                '@DATE@',
848                ),
849            array(
850                $id,
851                getNS($id),
852                $file,
853                utf8_ucfirst($file),
854                utf8_strtoupper($file),
855                $page,
856                utf8_ucfirst($page),
857                utf8_ucwords($page),
858                utf8_strtoupper($page),
859                $_SERVER['REMOTE_USER'],
860                $INFO['userinfo']['name'],
861                $INFO['userinfo']['mail'],
862                $conf['dformat'],
863                ), $tpl);
864
865    // we need the callback to work around strftime's char limit
866    $tpl = preg_replace_callback('/%./',create_function('$m','return strftime($m[0]);'),$tpl);
867
868    return $tpl;
869}
870
871
872/**
873 * Returns the raw Wiki Text in three slices.
874 *
875 * The range parameter needs to have the form "from-to"
876 * and gives the range of the section in bytes - no
877 * UTF-8 awareness is needed.
878 * The returned order is prefix, section and suffix.
879 *
880 * @author Andreas Gohr <andi@splitbrain.org>
881 */
882function rawWikiSlices($range,$id,$rev=''){
883    list($from,$to) = explode('-',$range,2);
884    $text = io_readWikiPage(wikiFN($id, $rev), $id, $rev);
885    if(!$from) $from = 0;
886    if(!$to)   $to   = strlen($text)+1;
887
888    $slices[0] = substr($text,0,$from-1);
889    $slices[1] = substr($text,$from-1,$to-$from);
890    $slices[2] = substr($text,$to);
891
892    return $slices;
893}
894
895/**
896 * Joins wiki text slices
897 *
898 * function to join the text slices with correct lineendings again.
899 * When the pretty parameter is set to true it adds additional empty
900 * lines between sections if needed (used on saving).
901 *
902 * @author Andreas Gohr <andi@splitbrain.org>
903 */
904function con($pre,$text,$suf,$pretty=false){
905    if($pretty){
906        if($pre && substr($pre,-1) != "\n") $pre .= "\n";
907        if($suf && substr($text,-1) != "\n") $text .= "\n";
908    }
909
910    // Avoid double newline above section when saving section edit
911    //if($pre) $pre .= "\n";
912    if($suf) $text .= "\n";
913    return $pre.$text.$suf;
914}
915
916/**
917 * Saves a wikitext by calling io_writeWikiPage.
918 * Also directs changelog and attic updates.
919 *
920 * @author Andreas Gohr <andi@splitbrain.org>
921 * @author Ben Coburn <btcoburn@silicodon.net>
922 */
923function saveWikiText($id,$text,$summary,$minor=false){
924    /* Note to developers:
925       This code is subtle and delicate. Test the behavior of
926       the attic and changelog with dokuwiki and external edits
927       after any changes. External edits change the wiki page
928       directly without using php or dokuwiki.
929     */
930    global $conf;
931    global $lang;
932    global $REV;
933    // ignore if no changes were made
934    if($text == rawWiki($id,'')){
935        return;
936    }
937
938    $file = wikiFN($id);
939    $old = @filemtime($file); // from page
940    $wasRemoved = empty($text);
941    $wasCreated = !@file_exists($file);
942    $wasReverted = ($REV==true);
943    $newRev = false;
944    $oldRev = getRevisions($id, -1, 1, 1024); // from changelog
945    $oldRev = (int)(empty($oldRev)?0:$oldRev[0]);
946    if(!@file_exists(wikiFN($id, $old)) && @file_exists($file) && $old>=$oldRev) {
947        // add old revision to the attic if missing
948        saveOldRevision($id);
949        // add a changelog entry if this edit came from outside dokuwiki
950        if ($old>$oldRev) {
951            addLogEntry($old, $id, DOKU_CHANGE_TYPE_EDIT, $lang['external_edit'], '', array('ExternalEdit'=>true));
952            // remove soon to be stale instructions
953            $cache = new cache_instructions($id, $file);
954            $cache->removeCache();
955        }
956    }
957
958    if ($wasRemoved){
959        // Send "update" event with empty data, so plugins can react to page deletion
960        $data = array(array($file, '', false), getNS($id), noNS($id), false);
961        trigger_event('IO_WIKIPAGE_WRITE', $data);
962        // pre-save deleted revision
963        @touch($file);
964        clearstatcache();
965        $newRev = saveOldRevision($id);
966        // remove empty file
967        @unlink($file);
968        // remove old meta info...
969        $mfiles = metaFiles($id);
970        $changelog = metaFN($id, '.changes');
971        $metadata  = metaFN($id, '.meta');
972        foreach ($mfiles as $mfile) {
973            // but keep per-page changelog to preserve page history and keep meta data
974            if (@file_exists($mfile) && $mfile!==$changelog && $mfile!==$metadata) { @unlink($mfile); }
975        }
976        // purge meta data
977        p_purge_metadata($id);
978        $del = true;
979        // autoset summary on deletion
980        if(empty($summary)) $summary = $lang['deleted'];
981        // remove empty namespaces
982        io_sweepNS($id, 'datadir');
983        io_sweepNS($id, 'mediadir');
984    }else{
985        // save file (namespace dir is created in io_writeWikiPage)
986        io_writeWikiPage($file, $text, $id);
987        // pre-save the revision, to keep the attic in sync
988        $newRev = saveOldRevision($id);
989        $del = false;
990    }
991
992    // select changelog line type
993    $extra = '';
994    $type = DOKU_CHANGE_TYPE_EDIT;
995    if ($wasReverted) {
996        $type = DOKU_CHANGE_TYPE_REVERT;
997        $extra = $REV;
998    }
999    else if ($wasCreated) { $type = DOKU_CHANGE_TYPE_CREATE; }
1000    else if ($wasRemoved) { $type = DOKU_CHANGE_TYPE_DELETE; }
1001    else if ($minor && $conf['useacl'] && $_SERVER['REMOTE_USER']) { $type = DOKU_CHANGE_TYPE_MINOR_EDIT; } //minor edits only for logged in users
1002
1003    addLogEntry($newRev, $id, $type, $summary, $extra);
1004    // send notify mails
1005    notify($id,'admin',$old,$summary,$minor);
1006    notify($id,'subscribers',$old,$summary,$minor);
1007
1008    // update the purgefile (timestamp of the last time anything within the wiki was changed)
1009    io_saveFile($conf['cachedir'].'/purgefile',time());
1010
1011    // if useheading is enabled, purge the cache of all linking pages
1012    if(useHeading('content')){
1013        require_once(DOKU_INC.'inc/fulltext.php');
1014        $pages = ft_backlinks($id);
1015        foreach ($pages as $page) {
1016            $cache = new cache_renderer($page, wikiFN($page), 'xhtml');
1017            $cache->removeCache();
1018        }
1019    }
1020}
1021
1022/**
1023 * moves the current version to the attic and returns its
1024 * revision date
1025 *
1026 * @author Andreas Gohr <andi@splitbrain.org>
1027 */
1028function saveOldRevision($id){
1029    global $conf;
1030    $oldf = wikiFN($id);
1031    if(!@file_exists($oldf)) return '';
1032    $date = filemtime($oldf);
1033    $newf = wikiFN($id,$date);
1034    io_writeWikiPage($newf, rawWiki($id), $id, $date);
1035    return $date;
1036}
1037
1038/**
1039 * Sends a notify mail on page change or registration
1040 *
1041 * @param  string  $id       The changed page
1042 * @param  string  $who      Who to notify (admin|subscribers|register)
1043 * @param  int     $rev      Old page revision
1044 * @param  string  $summary  What changed
1045 * @param  boolean $minor    Is this a minor edit?
1046 * @param  array   $replace  Additional string substitutions, @KEY@ to be replaced by value
1047 *
1048 * @author Andreas Gohr <andi@splitbrain.org>
1049 */
1050function notify($id,$who,$rev='',$summary='',$minor=false,$replace=array()){
1051    global $lang;
1052    global $conf;
1053    global $INFO;
1054
1055    // decide if there is something to do
1056    if($who == 'admin'){
1057        if(empty($conf['notify'])) return; //notify enabled?
1058        $text = rawLocale('mailtext');
1059        $to   = $conf['notify'];
1060        $bcc  = '';
1061    }elseif($who == 'subscribers'){
1062        if(!$conf['subscribers']) return; //subscribers enabled?
1063        if($conf['useacl'] && $_SERVER['REMOTE_USER'] && $minor) return; //skip minors
1064        $data = array('id' => $id, 'addresslist' => '', 'self' => false);
1065        trigger_event('COMMON_NOTIFY_ADDRESSLIST', $data,
1066                      'subscription_addresslist');
1067        $bcc = $data['addresslist'];
1068        if(empty($bcc)) return;
1069        $to   = '';
1070        $text = rawLocale('subscr_single');
1071    }elseif($who == 'register'){
1072        if(empty($conf['registernotify'])) return;
1073        $text = rawLocale('registermail');
1074        $to   = $conf['registernotify'];
1075        $bcc  = '';
1076    }else{
1077        return; //just to be safe
1078    }
1079
1080    $ip   = clientIP();
1081    $text = str_replace('@DATE@',dformat(),$text);
1082    $text = str_replace('@BROWSER@',$_SERVER['HTTP_USER_AGENT'],$text);
1083    $text = str_replace('@IPADDRESS@',$ip,$text);
1084    $text = str_replace('@HOSTNAME@',gethostsbyaddrs($ip),$text);
1085    $text = str_replace('@NEWPAGE@',wl($id,'',true,'&'),$text);
1086    $text = str_replace('@PAGE@',$id,$text);
1087    $text = str_replace('@TITLE@',$conf['title'],$text);
1088    $text = str_replace('@DOKUWIKIURL@',DOKU_URL,$text);
1089    $text = str_replace('@SUMMARY@',$summary,$text);
1090    $text = str_replace('@USER@',$_SERVER['REMOTE_USER'],$text);
1091
1092    foreach ($replace as $key => $substitution) {
1093        $text = str_replace('@'.strtoupper($key).'@',$substitution, $text);
1094    }
1095
1096    if($who == 'register'){
1097        $subject = $lang['mail_new_user'].' '.$summary;
1098    }elseif($rev){
1099        $subject = $lang['mail_changed'].' '.$id;
1100        $text = str_replace('@OLDPAGE@',wl($id,"rev=$rev",true,'&'),$text);
1101        require_once(DOKU_INC.'inc/DifferenceEngine.php');
1102        $df  = new Diff(explode("\n",rawWiki($id,$rev)),
1103                        explode("\n",rawWiki($id)));
1104        $dformat = new UnifiedDiffFormatter();
1105        $diff    = $dformat->format($df);
1106    }else{
1107        $subject=$lang['mail_newpage'].' '.$id;
1108        $text = str_replace('@OLDPAGE@','none',$text);
1109        $diff = rawWiki($id);
1110    }
1111    $text = str_replace('@DIFF@',$diff,$text);
1112    $subject = '['.$conf['title'].'] '.$subject;
1113
1114    $from = $conf['mailfrom'];
1115    $from = str_replace('@USER@',$_SERVER['REMOTE_USER'],$from);
1116    $from = str_replace('@NAME@',$INFO['userinfo']['name'],$from);
1117    $from = str_replace('@MAIL@',$INFO['userinfo']['mail'],$from);
1118
1119    mail_send($to,$subject,$text,$from,'',$bcc);
1120}
1121
1122/**
1123 * extracts the query from a search engine referrer
1124 *
1125 * @author Andreas Gohr <andi@splitbrain.org>
1126 * @author Todd Augsburger <todd@rollerorgans.com>
1127 */
1128function getGoogleQuery(){
1129    if (!isset($_SERVER['HTTP_REFERER'])) {
1130        return '';
1131    }
1132    $url = parse_url($_SERVER['HTTP_REFERER']);
1133
1134    $query = array();
1135
1136    // temporary workaround against PHP bug #49733
1137    // see http://bugs.php.net/bug.php?id=49733
1138    if(UTF8_MBSTRING) $enc = mb_internal_encoding();
1139    parse_str($url['query'],$query);
1140    if(UTF8_MBSTRING) mb_internal_encoding($enc);
1141
1142    $q = '';
1143    if(isset($query['q']))
1144        $q = $query['q'];        // google, live/msn, aol, ask, altavista, alltheweb, gigablast
1145    elseif(isset($query['p']))
1146        $q = $query['p'];        // yahoo
1147    elseif(isset($query['query']))
1148        $q = $query['query'];    // lycos, netscape, clusty, hotbot
1149    elseif(preg_match("#a9\.com#i",$url['host'])) // a9
1150        $q = urldecode(ltrim($url['path'],'/'));
1151
1152    if($q === '') return '';
1153    $q = preg_split('/[\s\'"\\\\`()\]\[?:!\.{};,#+*<>\\/]+/',$q,-1,PREG_SPLIT_NO_EMPTY);
1154    return $q;
1155}
1156
1157/**
1158 * Try to set correct locale
1159 *
1160 * @deprecated No longer used
1161 * @author     Andreas Gohr <andi@splitbrain.org>
1162 */
1163function setCorrectLocale(){
1164    global $conf;
1165    global $lang;
1166
1167    $enc = strtoupper($lang['encoding']);
1168    foreach ($lang['locales'] as $loc){
1169        //try locale
1170        if(@setlocale(LC_ALL,$loc)) return;
1171        //try loceale with encoding
1172        if(@setlocale(LC_ALL,"$loc.$enc")) return;
1173    }
1174    //still here? try to set from environment
1175    @setlocale(LC_ALL,"");
1176}
1177
1178/**
1179 * Return the human readable size of a file
1180 *
1181 * @param       int    $size   A file size
1182 * @param       int    $dec    A number of decimal places
1183 * @author      Martin Benjamin <b.martin@cybernet.ch>
1184 * @author      Aidan Lister <aidan@php.net>
1185 * @version     1.0.0
1186 */
1187function filesize_h($size, $dec = 1){
1188    $sizes = array('B', 'KB', 'MB', 'GB');
1189    $count = count($sizes);
1190    $i = 0;
1191
1192    while ($size >= 1024 && ($i < $count - 1)) {
1193        $size /= 1024;
1194        $i++;
1195    }
1196
1197    return round($size, $dec) . ' ' . $sizes[$i];
1198}
1199
1200/**
1201 * Return the given timestamp as human readable, fuzzy age
1202 *
1203 * @author Andreas Gohr <gohr@cosmocode.de>
1204 */
1205function datetime_h($dt){
1206    global $lang;
1207
1208    $ago = time() - $dt;
1209    if($ago > 24*60*60*30*12*2){
1210        return sprintf($lang['years'], round($ago/(24*60*60*30*12)));
1211    }
1212    if($ago > 24*60*60*30*2){
1213        return sprintf($lang['months'], round($ago/(24*60*60*30)));
1214    }
1215    if($ago > 24*60*60*7*2){
1216        return sprintf($lang['weeks'], round($ago/(24*60*60*7)));
1217    }
1218    if($ago > 24*60*60*2){
1219        return sprintf($lang['days'], round($ago/(24*60*60)));
1220    }
1221    if($ago > 60*60*2){
1222        return sprintf($lang['hours'], round($ago/(60*60)));
1223    }
1224    if($ago > 60*2){
1225        return sprintf($lang['minutes'], round($ago/(60)));
1226    }
1227    return sprintf($lang['seconds'], $ago);
1228}
1229
1230/**
1231 * Wraps around strftime but provides support for fuzzy dates
1232 *
1233 * The format default to $conf['dformat']. It is passed to
1234 * strftime - %f can be used to get the value from datetime_h()
1235 *
1236 * @see datetime_h
1237 * @author Andreas Gohr <gohr@cosmocode.de>
1238 */
1239function dformat($dt=null,$format=''){
1240    global $conf;
1241
1242    if(is_null($dt)) $dt = time();
1243    $dt = (int) $dt;
1244    if(!$format) $format = $conf['dformat'];
1245
1246    $format = str_replace('%f',datetime_h($dt),$format);
1247    return strftime($format,$dt);
1248}
1249
1250/**
1251 * return an obfuscated email address in line with $conf['mailguard'] setting
1252 *
1253 * @author Harry Fuecks <hfuecks@gmail.com>
1254 * @author Christopher Smith <chris@jalakai.co.uk>
1255 */
1256function obfuscate($email) {
1257    global $conf;
1258
1259    switch ($conf['mailguard']) {
1260        case 'visible' :
1261            $obfuscate = array('@' => ' [at] ', '.' => ' [dot] ', '-' => ' [dash] ');
1262            return strtr($email, $obfuscate);
1263
1264        case 'hex' :
1265            $encode = '';
1266            $len = strlen($email);
1267            for ($x=0; $x < $len; $x++){
1268                $encode .= '&#x' . bin2hex($email{$x}).';';
1269            }
1270            return $encode;
1271
1272        case 'none' :
1273        default :
1274            return $email;
1275    }
1276}
1277
1278/**
1279 * Removes quoting backslashes
1280 *
1281 * @author Andreas Gohr <andi@splitbrain.org>
1282 */
1283function unslash($string,$char="'"){
1284    return str_replace('\\'.$char,$char,$string);
1285}
1286
1287/**
1288 * Convert php.ini shorthands to byte
1289 *
1290 * @author <gilthans dot NO dot SPAM at gmail dot com>
1291 * @link   http://de3.php.net/manual/en/ini.core.php#79564
1292 */
1293function php_to_byte($v){
1294    $l = substr($v, -1);
1295    $ret = substr($v, 0, -1);
1296    switch(strtoupper($l)){
1297        case 'P':
1298            $ret *= 1024;
1299        case 'T':
1300            $ret *= 1024;
1301        case 'G':
1302            $ret *= 1024;
1303        case 'M':
1304            $ret *= 1024;
1305        case 'K':
1306            $ret *= 1024;
1307        break;
1308    }
1309    return $ret;
1310}
1311
1312/**
1313 * Wrapper around preg_quote adding the default delimiter
1314 */
1315function preg_quote_cb($string){
1316    return preg_quote($string,'/');
1317}
1318
1319/**
1320 * Shorten a given string by removing data from the middle
1321 *
1322 * You can give the string in two parts, the first part $keep
1323 * will never be shortened. The second part $short will be cut
1324 * in the middle to shorten but only if at least $min chars are
1325 * left to display it. Otherwise it will be left off.
1326 *
1327 * @param string $keep   the part to keep
1328 * @param string $short  the part to shorten
1329 * @param int    $max    maximum chars you want for the whole string
1330 * @param int    $min    minimum number of chars to have left for middle shortening
1331 * @param string $char   the shortening character to use
1332 */
1333function shorten($keep,$short,$max,$min=9,$char='…'){
1334    $max = $max - utf8_strlen($keep);
1335    if($max < $min) return $keep;
1336    $len = utf8_strlen($short);
1337    if($len <= $max) return $keep.$short;
1338    $half = floor($max/2);
1339    return $keep.utf8_substr($short,0,$half-1).$char.utf8_substr($short,$len-$half);
1340}
1341
1342/**
1343 * Return the users realname or e-mail address for use
1344 * in page footer and recent changes pages
1345 *
1346 * @author Andy Webber <dokuwiki AT andywebber DOT com>
1347 */
1348function editorinfo($username){
1349    global $conf;
1350    global $auth;
1351
1352    switch($conf['showuseras']){
1353        case 'username':
1354        case 'email':
1355        case 'email_link':
1356            if($auth) $info = $auth->getUserData($username);
1357            break;
1358        default:
1359            return hsc($username);
1360    }
1361
1362    if(isset($info) && $info) {
1363        switch($conf['showuseras']){
1364            case 'username':
1365                return hsc($info['name']);
1366            case 'email':
1367                return obfuscate($info['mail']);
1368            case 'email_link':
1369                $mail=obfuscate($info['mail']);
1370                return '<a href="mailto:'.$mail.'">'.$mail.'</a>';
1371            default:
1372                return hsc($username);
1373        }
1374    } else {
1375        return hsc($username);
1376    }
1377}
1378
1379/**
1380 * Returns the path to a image file for the currently chosen license.
1381 * When no image exists, returns an empty string
1382 *
1383 * @author Andreas Gohr <andi@splitbrain.org>
1384 * @param  string $type - type of image 'badge' or 'button'
1385 */
1386function license_img($type){
1387    global $license;
1388    global $conf;
1389    if(!$conf['license']) return '';
1390    if(!is_array($license[$conf['license']])) return '';
1391    $lic = $license[$conf['license']];
1392    $try = array();
1393    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.png';
1394    $try[] = 'lib/images/license/'.$type.'/'.$conf['license'].'.gif';
1395    if(substr($conf['license'],0,3) == 'cc-'){
1396        $try[] = 'lib/images/license/'.$type.'/cc.png';
1397    }
1398    foreach($try as $src){
1399        if(@file_exists(DOKU_INC.$src)) return $src;
1400    }
1401    return '';
1402}
1403
1404/**
1405 * Checks if the given amount of memory is available
1406 *
1407 * If the memory_get_usage() function is not available the
1408 * function just assumes $bytes of already allocated memory
1409 *
1410 * @param  int $mem  Size of memory you want to allocate in bytes
1411 * @param  int $used already allocated memory (see above)
1412 * @author Filip Oscadal <webmaster@illusionsoftworks.cz>
1413 * @author Andreas Gohr <andi@splitbrain.org>
1414 */
1415function is_mem_available($mem,$bytes=1048576){
1416    $limit = trim(ini_get('memory_limit'));
1417    if(empty($limit)) return true; // no limit set!
1418
1419    // parse limit to bytes
1420    $limit = php_to_byte($limit);
1421
1422    // get used memory if possible
1423    if(function_exists('memory_get_usage')){
1424        $used = memory_get_usage();
1425    }else{
1426        $used = $bytes;
1427    }
1428
1429    if($used+$mem > $limit){
1430        return false;
1431    }
1432
1433    return true;
1434}
1435
1436/**
1437 * Send a HTTP redirect to the browser
1438 *
1439 * Works arround Microsoft IIS cookie sending bug. Exits the script.
1440 *
1441 * @link   http://support.microsoft.com/kb/q176113/
1442 * @author Andreas Gohr <andi@splitbrain.org>
1443 */
1444function send_redirect($url){
1445    // always close the session
1446    session_write_close();
1447
1448    // check if running on IIS < 6 with CGI-PHP
1449    if( isset($_SERVER['SERVER_SOFTWARE']) && isset($_SERVER['GATEWAY_INTERFACE']) &&
1450        (strpos($_SERVER['GATEWAY_INTERFACE'],'CGI') !== false) &&
1451        (preg_match('|^Microsoft-IIS/(\d)\.\d$|', trim($_SERVER['SERVER_SOFTWARE']), $matches)) &&
1452        $matches[1] < 6 ){
1453        header('Refresh: 0;url='.$url);
1454    }else{
1455        header('Location: '.$url);
1456    }
1457    exit;
1458}
1459
1460/**
1461 * Validate a value using a set of valid values
1462 *
1463 * This function checks whether a specified value is set and in the array
1464 * $valid_values. If not, the function returns a default value or, if no
1465 * default is specified, throws an exception.
1466 *
1467 * @param string $param        The name of the parameter
1468 * @param array  $valid_values A set of valid values; Optionally a default may
1469 *                             be marked by the key “default”.
1470 * @param array  $array        The array containing the value (typically $_POST
1471 *                             or $_GET)
1472 * @param string $exc          The text of the raised exception
1473 *
1474 * @author Adrian Lang <lang@cosmocode.de>
1475 */
1476function valid_input_set($param, $valid_values, $array, $exc = '') {
1477    if (isset($array[$param]) && in_array($array[$param], $valid_values)) {
1478        return $array[$param];
1479    } elseif (isset($valid_values['default'])) {
1480        return $valid_values['default'];
1481    } else {
1482        throw new Exception($exc);
1483    }
1484}
1485
1486//Setup VIM: ex: et ts=2 enc=utf-8 :
1487