xref: /dokuwiki/inc/pageutils.php (revision 2844584ff3fc18be6cdd83e4cb80f35197a962d1)
1b625487dSandi<?php
2b625487dSandi/**
3b625487dSandi * Utilities for handling pagenames
4b625487dSandi *
5b625487dSandi * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
6b625487dSandi * @author     Andreas Gohr <andi@splitbrain.org>
71380fc45SAndreas Gohr * @todo       Combine similar functions like {wiki,media,meta}FN()
8b625487dSandi */
9b625487dSandi
106c7843b5Sandi/**
116de3759aSAndreas Gohr * Fetch the an ID from request
126c7843b5Sandi *
136c7843b5Sandi * Uses either standard $_REQUEST variable or extracts it from
146c7843b5Sandi * the full request URI when userewrite is set to 2
156c7843b5Sandi *
1642905504SAndreas Gohr * For $param='id' $conf['start'] is returned if no id was found.
1742905504SAndreas Gohr * If the second parameter is true (default) the ID is cleaned.
186c7843b5Sandi *
196c7843b5Sandi * @author Andreas Gohr <andi@splitbrain.org>
206c7843b5Sandi */
2142905504SAndreas Gohrfunction getID($param='id',$clean=true){
226c7843b5Sandi  global $conf;
236c7843b5Sandi
2448665d38SAndreas Gohr  $id = $_REQUEST[$param];
2548665d38SAndreas Gohr
266c7843b5Sandi  //construct page id from request URI
276c7843b5Sandi  if(empty($id) && $conf['userewrite'] == 2){
286c7843b5Sandi    //get the script URL
296c7843b5Sandi    if($conf['basedir']){
3081124000Sjan      $relpath = '';
3181124000Sjan      if($param != 'id') {
3281124000Sjan        $relpath = 'lib/exe/';
3381124000Sjan      }
3481124000Sjan      $script = $conf['basedir'].$relpath.basename($_SERVER['SCRIPT_FILENAME']);
356c7843b5Sandi    }elseif($_SERVER['DOCUMENT_ROOT'] && $_SERVER['SCRIPT_FILENAME']){
366c7843b5Sandi      $script = preg_replace ('/^'.preg_quote($_SERVER['DOCUMENT_ROOT'],'/').'/','',
376c7843b5Sandi                              $_SERVER['SCRIPT_FILENAME']);
386c7843b5Sandi      $script = '/'.$script;
396c7843b5Sandi    }else{
406c7843b5Sandi      $script = $_SERVER['SCRIPT_NAME'];
416c7843b5Sandi    }
426c7843b5Sandi
4352339126Sandi    //clean script and request (fixes a windows problem)
4452339126Sandi    $script  = preg_replace('/\/\/+/','/',$script);
4552339126Sandi    $request = preg_replace('/\/\/+/','/',$_SERVER['REQUEST_URI']);
4652339126Sandi
476c7843b5Sandi    //remove script URL and Querystring to gain the id
4852339126Sandi    if(preg_match('/^'.preg_quote($script,'/').'(.*)/',$request, $match)){
496c7843b5Sandi      $id = preg_replace ('/\?.*/','',$match[1]);
506c7843b5Sandi    }
516de3759aSAndreas Gohr    $id = urldecode($id);
5242905504SAndreas Gohr    //strip leading slashes
5342905504SAndreas Gohr    $id = preg_replace('!^/+!','',$id);
546c7843b5Sandi  }
5542905504SAndreas Gohr  if($clean) $id = cleanID($id);
560868021bSAndreas Gohr  if(empty($id) && $param=='id') $id = $conf['start'];
576c7843b5Sandi
586c7843b5Sandi  return $id;
596c7843b5Sandi}
60b625487dSandi
61b625487dSandi/**
62b625487dSandi * Remove unwanted chars from ID
63b625487dSandi *
64b625487dSandi * Cleans a given ID to only use allowed characters. Accented characters are
65b625487dSandi * converted to unaccented ones
66b625487dSandi *
67b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
688a831f2bSAndreas Gohr * @param  string  $id    The pageid to clean
698a831f2bSAndreas Gohr * @param  boolean $ascii Force ASCII
70b625487dSandi */
718a831f2bSAndreas Gohrfunction cleanID($id,$ascii=false){
72b625487dSandi  global $conf;
73b625487dSandi  global $lang;
744b5db43bSjoe.lapp  static $sepcharpat = null;
754b5db43bSjoe.lapp
764b5db43bSjoe.lapp  $sepchar = $conf['sepchar'];
774b5db43bSjoe.lapp  if($sepcharpat == null) // build string only once to save clock cycles
784b5db43bSjoe.lapp    $sepcharpat = '#\\'.$sepchar.'+#';
794b5db43bSjoe.lapp
80b625487dSandi  $id = trim($id);
81b625487dSandi  $id = utf8_strtolower($id);
82b625487dSandi
83b625487dSandi  //alternative namespace seperator
84b625487dSandi  $id = strtr($id,';',':');
85b625487dSandi  if($conf['useslash']){
86b625487dSandi    $id = strtr($id,'/',':');
87b625487dSandi  }else{
884eeffcd2SAndreas Gohr    $id = strtr($id,'/',$sepchar);
89b625487dSandi  }
90b625487dSandi
918a831f2bSAndreas Gohr  if($conf['deaccent'] == 2 || $ascii) $id = utf8_romanize($id);
928a831f2bSAndreas Gohr  if($conf['deaccent'] || $ascii) $id = utf8_deaccent($id,-1);
93b625487dSandi
94b625487dSandi  //remove specials
95ad81d431SAndreas Gohr  $id = utf8_stripspecials($id,$sepchar,'\*');
96b625487dSandi
978a831f2bSAndreas Gohr  if($ascii) $id = utf8_strip($id);
988a831f2bSAndreas Gohr
99b625487dSandi  //clean up
1004b5db43bSjoe.lapp  $id = preg_replace($sepcharpat,$sepchar,$id);
101b625487dSandi  $id = preg_replace('#:+#',':',$id);
102b625487dSandi  $id = trim($id,':._-');
103b625487dSandi  $id = preg_replace('#:[:\._\-]+#',':',$id);
104b625487dSandi
105b625487dSandi  return($id);
106b625487dSandi}
107b625487dSandi
108b625487dSandi/**
109b625487dSandi * Return namespacepart of a wiki ID
110b625487dSandi *
111b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
112b625487dSandi */
113b625487dSandifunction getNS($id){
114c4e0e4a1SAndreas Gohr  $pos = strrpos($id,':');
115c4e0e4a1SAndreas Gohr  if($pos!==false){
116c4e0e4a1SAndreas Gohr    return substr($id,0,$pos);
117b625487dSandi  }
118b625487dSandi  return false;
119b625487dSandi}
120b625487dSandi
121b625487dSandi/**
122b625487dSandi * Returns the ID without the namespace
123b625487dSandi *
124b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
125b625487dSandi */
126b625487dSandifunction noNS($id) {
127*2844584fSBen Coburn  $pos = strrpos($id, ':');
128*2844584fSBen Coburn  if ($pos!==false) {
129*2844584fSBen Coburn    return substr($id, $pos+1);
130*2844584fSBen Coburn  } else {
131*2844584fSBen Coburn    return $id;
132*2844584fSBen Coburn  }
133b625487dSandi}
134b625487dSandi
135b625487dSandi/**
136b625487dSandi * returns the full path to the datafile specified by ID and
137b625487dSandi * optional revision
138b625487dSandi *
139b625487dSandi * The filename is URL encoded to protect Unicode chars
140b625487dSandi *
141b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
142b625487dSandi */
143b625487dSandifunction wikiFN($id,$rev=''){
144b625487dSandi  global $conf;
145b625487dSandi  $id = cleanID($id);
146b625487dSandi  $id = str_replace(':','/',$id);
147b625487dSandi  if(empty($rev)){
148b625487dSandi    $fn = $conf['datadir'].'/'.utf8_encodeFN($id).'.txt';
149b625487dSandi  }else{
150b625487dSandi    $fn = $conf['olddir'].'/'.utf8_encodeFN($id).'.'.$rev.'.txt';
151b625487dSandi    if($conf['usegzip'] && !@file_exists($fn)){
152b625487dSandi      //return gzip if enabled and plaintext doesn't exist
153b625487dSandi      $fn .= '.gz';
154b625487dSandi    }
155b625487dSandi  }
156b625487dSandi  return $fn;
157b625487dSandi}
158b625487dSandi
159b625487dSandi/**
160c9b4bd1eSBen Coburn * Returns the full path to the file for locking the page while editing.
161c9b4bd1eSBen Coburn *
162c9b4bd1eSBen Coburn * @author Ben Coburn <btcoburn@silicodon.net>
163c9b4bd1eSBen Coburn */
164c9b4bd1eSBen Coburnfunction wikiLockFN($id) {
165c9b4bd1eSBen Coburn  global $conf;
166c9b4bd1eSBen Coburn  return $conf['lockdir'].'/'.sha1(cleanID($id)).'.lock';
167c9b4bd1eSBen Coburn}
168c9b4bd1eSBen Coburn
169c9b4bd1eSBen Coburn
170c9b4bd1eSBen Coburn/**
1711380fc45SAndreas Gohr * returns the full path to the meta file specified by ID and extension
172b158d625SSteven Danz *
173b158d625SSteven Danz * The filename is URL encoded to protect Unicode chars
174b158d625SSteven Danz *
175b158d625SSteven Danz * @author Steven Danz <steven-danz@kc.rr.com>
176b158d625SSteven Danz */
1771380fc45SAndreas Gohrfunction metaFN($id,$ext){
178b158d625SSteven Danz  global $conf;
179b158d625SSteven Danz  $id = cleanID($id);
180b158d625SSteven Danz  $id = str_replace(':','/',$id);
1811380fc45SAndreas Gohr  $fn = $conf['metadir'].'/'.utf8_encodeFN($id).$ext;
182b158d625SSteven Danz  return $fn;
183b158d625SSteven Danz}
184b158d625SSteven Danz
185b158d625SSteven Danz/**
186e1f3d9e1SEsther Brunner * returns an array of full paths to all metafiles of a given ID
187e1f3d9e1SEsther Brunner *
188e1f3d9e1SEsther Brunner * @author Esther Brunner <esther@kaffeehaus.ch>
189e1f3d9e1SEsther Brunner */
190e1f3d9e1SEsther Brunnerfunction metaFiles($id){
191e1f3d9e1SEsther Brunner   $name   = noNS($id);
192e1f3d9e1SEsther Brunner   $dir    = metaFN(getNS($id),'');
193e1f3d9e1SEsther Brunner   $files  = array();
194e1f3d9e1SEsther Brunner
195e1f3d9e1SEsther Brunner   $dh = @opendir($dir);
1965011da9dSEsther Brunner   if(!$dh) return $files;
197e1f3d9e1SEsther Brunner   while(($file = readdir($dh)) !== false){
1981a54dfabSEsther Brunner     if(strpos($file,$name.'.') === 0 && !is_dir($dir.$file))
199e1f3d9e1SEsther Brunner       $files[] = $dir.$file;
200e1f3d9e1SEsther Brunner   }
201e1f3d9e1SEsther Brunner   closedir($dh);
202e1f3d9e1SEsther Brunner
203e1f3d9e1SEsther Brunner   return $files;
204e1f3d9e1SEsther Brunner}
205e1f3d9e1SEsther Brunner
206e1f3d9e1SEsther Brunner/**
207b625487dSandi * returns the full path to the mediafile specified by ID
208b625487dSandi *
209b625487dSandi * The filename is URL encoded to protect Unicode chars
210b625487dSandi *
211b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
212b625487dSandi */
213b625487dSandifunction mediaFN($id){
214b625487dSandi  global $conf;
215b625487dSandi  $id = cleanID($id);
216b625487dSandi  $id = str_replace(':','/',$id);
217b625487dSandi    $fn = $conf['mediadir'].'/'.utf8_encodeFN($id);
218b625487dSandi  return $fn;
219b625487dSandi}
220b625487dSandi
221b625487dSandi/**
222b625487dSandi * Returns the full filepath to a localized textfile if local
223b625487dSandi * version isn't found the english one is returned
224b625487dSandi *
225b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
226b625487dSandi */
227b625487dSandifunction localeFN($id){
228b625487dSandi  global $conf;
229bc3b6aecSandi  $file = DOKU_INC.'inc/lang/'.$conf['lang'].'/'.$id.'.txt';
230b625487dSandi  if(!@file_exists($file)){
231b625487dSandi    //fall back to english
232bc3b6aecSandi    $file = DOKU_INC.'inc/lang/en/'.$id.'.txt';
233b625487dSandi  }
234b625487dSandi  return $file;
235b625487dSandi}
236b625487dSandi
237b625487dSandi/**
238c4e0e4a1SAndreas Gohr * Resolve relative paths in IDs
239c4e0e4a1SAndreas Gohr *
240c4e0e4a1SAndreas Gohr * Do not call directly use resolve_mediaid or resolve_pageid
241c4e0e4a1SAndreas Gohr * instead
242c4e0e4a1SAndreas Gohr *
243c4e0e4a1SAndreas Gohr * Partyly based on a cleanPath function found at
244c4e0e4a1SAndreas Gohr * http://www.php.net/manual/en/function.realpath.php#57016
245c4e0e4a1SAndreas Gohr *
246c4e0e4a1SAndreas Gohr * @author <bart at mediawave dot nl>
247c4e0e4a1SAndreas Gohr */
248a6ef4796SAndreas Gohrfunction resolve_id($ns,$id,$clean=true){
249c4e0e4a1SAndreas Gohr  // if the id starts with a dot we need to handle the
250c4e0e4a1SAndreas Gohr  // relative stuff
251c4e0e4a1SAndreas Gohr  if($id{0} == '.'){
252c4e0e4a1SAndreas Gohr    // normalize initial dots without a colon
253c4e0e4a1SAndreas Gohr    $id = preg_replace('/^(\.+)(?=[^:\.])/','\1:',$id);
254c4e0e4a1SAndreas Gohr    // prepend the current namespace
255c4e0e4a1SAndreas Gohr    $id = $ns.':'.$id;
256c4e0e4a1SAndreas Gohr
257c4e0e4a1SAndreas Gohr    // cleanup relatives
258c4e0e4a1SAndreas Gohr    $result = array();
259c4e0e4a1SAndreas Gohr    $pathA  = explode(':', $id);
260c4e0e4a1SAndreas Gohr    if (!$pathA[0]) $result[] = '';
261c4e0e4a1SAndreas Gohr    foreach ($pathA AS $key => $dir) {
262c4e0e4a1SAndreas Gohr      if ($dir == '..') {
263c4e0e4a1SAndreas Gohr        if (end($result) == '..') {
264c4e0e4a1SAndreas Gohr          $result[] = '..';
265c4e0e4a1SAndreas Gohr        } elseif (!array_pop($result)) {
266c4e0e4a1SAndreas Gohr          $result[] = '..';
267c4e0e4a1SAndreas Gohr        }
268c4e0e4a1SAndreas Gohr      } elseif ($dir && $dir != '.') {
269c4e0e4a1SAndreas Gohr        $result[] = $dir;
270c4e0e4a1SAndreas Gohr      }
271c4e0e4a1SAndreas Gohr    }
272c4e0e4a1SAndreas Gohr    if (!end($pathA)) $result[] = '';
273c4e0e4a1SAndreas Gohr    $id = implode(':', $result);
274c4e0e4a1SAndreas Gohr  }elseif($ns !== false && strpos($id,':') === false){
275c4e0e4a1SAndreas Gohr    //if link contains no namespace. add current namespace (if any)
276c4e0e4a1SAndreas Gohr    $id = $ns.':'.$id;
277c4e0e4a1SAndreas Gohr  }
278c4e0e4a1SAndreas Gohr
279a6ef4796SAndreas Gohr  if($clean) $id = cleanID($id);
280a6ef4796SAndreas Gohr  return $id;
281c4e0e4a1SAndreas Gohr}
282c4e0e4a1SAndreas Gohr
283c4e0e4a1SAndreas Gohr/**
284b625487dSandi * Returns a full media id
285b625487dSandi *
286b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
287b625487dSandi */
28837e34a5eSandifunction resolve_mediaid($ns,&$page,&$exists){
289c4e0e4a1SAndreas Gohr  $page   = resolve_id($ns,$page);
290b625487dSandi  $file   = mediaFN($page);
291b625487dSandi  $exists = @file_exists($file);
292b625487dSandi}
293b625487dSandi
294b625487dSandi/**
295b625487dSandi * Returns a full page id
296b625487dSandi *
297b625487dSandi * @author Andreas Gohr <andi@splitbrain.org>
298b625487dSandi */
29937e34a5eSandifunction resolve_pageid($ns,&$page,&$exists){
300b625487dSandi  global $conf;
3010b7c14c2Sandi  $exists = false;
302b625487dSandi
303b625487dSandi  //keep hashlink if exists then clean both parts
304b625487dSandi  list($page,$hash) = split('#',$page,2);
305b625487dSandi  $hash = cleanID($hash);
306a6ef4796SAndreas Gohr  $page = resolve_id($ns,$page,false); // resolve but don't clean, yet
307b625487dSandi
308a6ef4796SAndreas Gohr  // get filename (calls clean itself)
309b625487dSandi  $file = wikiFN($page);
310b625487dSandi
311a6ef4796SAndreas Gohr  // if ends with colon we have a namespace link
312a6ef4796SAndreas Gohr  if(substr($page,-1) == ':'){
313a6ef4796SAndreas Gohr    if(@file_exists(wikiFN($page.$conf['start']))){
314a6ef4796SAndreas Gohr      // start page inside namespace
315a6ef4796SAndreas Gohr      $page = $page.$conf['start'];
316a6ef4796SAndreas Gohr      $exists = true;
317a6ef4796SAndreas Gohr    }elseif(@file_exists(wikiFN($page.noNS(cleanID($page))))){
318a6ef4796SAndreas Gohr      // page named like the NS inside the NS
319a6ef4796SAndreas Gohr      $page = $page.noNS(cleanID($page));
320a6ef4796SAndreas Gohr      $exists = true;
321a6ef4796SAndreas Gohr    }elseif(@file_exists(wikiFN($page))){
322a6ef4796SAndreas Gohr      // page like namespace exists
323a6ef4796SAndreas Gohr      $page = $page;
324a6ef4796SAndreas Gohr      $exists = true;
325a6ef4796SAndreas Gohr    }else{
326a6ef4796SAndreas Gohr      // fall back to default
327a6ef4796SAndreas Gohr      $page = $page.$conf['start'];
328a6ef4796SAndreas Gohr    }
329a6ef4796SAndreas Gohr  }else{
330b625487dSandi    //check alternative plural/nonplural form
331b625487dSandi    if(!@file_exists($file)){
332b625487dSandi      if( $conf['autoplural'] ){
333b625487dSandi        if(substr($page,-1) == 's'){
334b625487dSandi          $try = substr($page,0,-1);
335b625487dSandi        }else{
336b625487dSandi          $try = $page.'s';
337b625487dSandi        }
338b625487dSandi        if(@file_exists(wikiFN($try))){
339b625487dSandi          $page   = $try;
340b625487dSandi          $exists = true;
341b625487dSandi        }
342b625487dSandi      }
343b625487dSandi    }else{
344b625487dSandi      $exists = true;
345b625487dSandi    }
346a6ef4796SAndreas Gohr  }
347a6ef4796SAndreas Gohr
348a6ef4796SAndreas Gohr  // now make sure we have a clean page
349a6ef4796SAndreas Gohr  $page = cleanID($page);
350b625487dSandi
351b625487dSandi  //add hash if any
352b2d7d3f2Sandi  if(!empty($hash)) $page .= '#'.$hash;
353b625487dSandi}
354b625487dSandi
35598407a7aSandi/**
35698407a7aSandi * Returns the name of a cachefile from given data
35798407a7aSandi *
35898407a7aSandi * The needed directory is created by this function!
35998407a7aSandi *
36098407a7aSandi * @author Andreas Gohr <andi@splitbrain.org>
36198407a7aSandi *
36298407a7aSandi * @param string $data  This data is used to create a unique md5 name
36398407a7aSandi * @param string $ext   This is appended to the filename if given
36498407a7aSandi * @return string       The filename of the cachefile
36598407a7aSandi */
36698407a7aSandifunction getCacheName($data,$ext=''){
36798407a7aSandi  global $conf;
36898407a7aSandi  $md5  = md5($data);
36998407a7aSandi  $file = $conf['cachedir'].'/'.$md5{0}.'/'.$md5.$ext;
37098407a7aSandi  io_makeFileDir($file);
37198407a7aSandi  return $file;
37298407a7aSandi}
37398407a7aSandi
3740dc92c6fSAndreas Gohr/**
3750dc92c6fSAndreas Gohr * Checks a pageid against $conf['hidepages']
3760dc92c6fSAndreas Gohr *
3770dc92c6fSAndreas Gohr * @author Andreas Gohr <gohr@cosmocode.de>
3780dc92c6fSAndreas Gohr */
3790dc92c6fSAndreas Gohrfunction isHiddenPage($id){
3800dc92c6fSAndreas Gohr  global $conf;
3810dc92c6fSAndreas Gohr  if(empty($conf['hidepages'])) return false;
3820dc92c6fSAndreas Gohr
3830dc92c6fSAndreas Gohr  if(preg_match('/'.$conf['hidepages'].'/ui',':'.$id)){
3840dc92c6fSAndreas Gohr    return true;
3850dc92c6fSAndreas Gohr  }
3860dc92c6fSAndreas Gohr  return false;
3870dc92c6fSAndreas Gohr}
3880dc92c6fSAndreas Gohr
3890dc92c6fSAndreas Gohr/**
3900dc92c6fSAndreas Gohr * Reverse of isHiddenPage
3910dc92c6fSAndreas Gohr *
3920dc92c6fSAndreas Gohr * @author Andreas Gohr <gohr@cosmocode.de>
3930dc92c6fSAndreas Gohr */
3940dc92c6fSAndreas Gohrfunction isVisiblePage($id){
3950dc92c6fSAndreas Gohr  return !isHiddenPage($id);
3960dc92c6fSAndreas Gohr}
3970dc92c6fSAndreas Gohr
398254e5c84SBen Coburn/**
399254e5c84SBen Coburn * Checks and sets HTTP headers for conditional HTTP requests
400254e5c84SBen Coburn *
401254e5c84SBen Coburn * @author Simon Willison <swillison@gmail.com>
402254e5c84SBen Coburn * @link   http://simon.incutio.com/archive/2003/04/23/conditionalGet
403254e5c84SBen Coburn */
404254e5c84SBen Coburnfunction http_conditionalRequest($timestamp){
405254e5c84SBen Coburn    // A PHP implementation of conditional get, see
406254e5c84SBen Coburn    //   http://fishbowl.pastiche.org/archives/001132.html
407254e5c84SBen Coburn    $last_modified = substr(date('r', $timestamp), 0, -5).'GMT';
408254e5c84SBen Coburn    $etag = '"'.md5($last_modified).'"';
409254e5c84SBen Coburn    // Send the headers
410254e5c84SBen Coburn    header("Last-Modified: $last_modified");
411254e5c84SBen Coburn    header("ETag: $etag");
412254e5c84SBen Coburn    // See if the client has provided the required headers
413254e5c84SBen Coburn    $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ?
414254e5c84SBen Coburn        stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE']) :
415254e5c84SBen Coburn        false;
416254e5c84SBen Coburn    $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ?
417254e5c84SBen Coburn        stripslashes($_SERVER['HTTP_IF_NONE_MATCH']) :
418254e5c84SBen Coburn        false;
419254e5c84SBen Coburn    if (!$if_modified_since && !$if_none_match) {
420254e5c84SBen Coburn        return;
421254e5c84SBen Coburn    }
422254e5c84SBen Coburn    // At least one of the headers is there - check them
423254e5c84SBen Coburn    if ($if_none_match && $if_none_match != $etag) {
424254e5c84SBen Coburn        return; // etag is there but doesn't match
425254e5c84SBen Coburn    }
426254e5c84SBen Coburn    if ($if_modified_since && $if_modified_since != $last_modified) {
427254e5c84SBen Coburn        return; // if-modified-since is there but doesn't match
428254e5c84SBen Coburn    }
429254e5c84SBen Coburn    // Nothing has changed since their last request - serve a 304 and exit
430254e5c84SBen Coburn    header('HTTP/1.0 304 Not Modified');
431254e5c84SBen Coburn    exit;
432254e5c84SBen Coburn}
433254e5c84SBen Coburn
434b625487dSandi//Setup VIM: ex: et ts=2 enc=utf-8 :
435