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/inc/ -> io.php (source)

   1  <?php
   2  /**
   3   * File IO functions
   4   *
   5   * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
   6   * @author     Andreas Gohr <andi@splitbrain.org>
   7   */
   8  
   9  use dokuwiki\HTTP\DokuHTTPClient;
  10  use dokuwiki\Extension\Event;
  11  
  12  /**
  13   * Removes empty directories
  14   *
  15   * Sends IO_NAMESPACE_DELETED events for 'pages' and 'media' namespaces.
  16   * Event data:
  17   * $data[0]    ns: The colon separated namespace path minus the trailing page name.
  18   * $data[1]    ns_type: 'pages' or 'media' namespace tree.
  19   *
  20   * @param string $id      - a pageid, the namespace of that id will be tried to deleted
  21   * @param string $basedir - the config name of the type to delete (datadir or mediadir usally)
  22   * @return bool - true if at least one namespace was deleted
  23   *
  24   * @author  Andreas Gohr <andi@splitbrain.org>
  25   * @author Ben Coburn <btcoburn@silicodon.net>
  26   */
  27  function io_sweepNS($id,$basedir='datadir'){
  28      global $conf;
  29      $types = array ('datadir'=>'pages', 'mediadir'=>'media');
  30      $ns_type = (isset($types[$basedir])?$types[$basedir]:false);
  31  
  32      $delone = false;
  33  
  34      //scan all namespaces
  35      while(($id = getNS($id)) !== false){
  36          $dir = $conf[$basedir].'/'.utf8_encodeFN(str_replace(':','/',$id));
  37  
  38          //try to delete dir else return
  39          if(@rmdir($dir)) {
  40              if ($ns_type!==false) {
  41                  $data = array($id, $ns_type);
  42                  $delone = true; // we deleted at least one dir
  43                  Event::createAndTrigger('IO_NAMESPACE_DELETED', $data);
  44              }
  45          } else { return $delone; }
  46      }
  47      return $delone;
  48  }
  49  
  50  /**
  51   * Used to read in a DokuWiki page from file, and send IO_WIKIPAGE_READ events.
  52   *
  53   * Generates the action event which delegates to io_readFile().
  54   * Action plugins are allowed to modify the page content in transit.
  55   * The file path should not be changed.
  56   *
  57   * Event data:
  58   * $data[0]    The raw arguments for io_readFile as an array.
  59   * $data[1]    ns: The colon separated namespace path minus the trailing page name. (false if root ns)
  60   * $data[2]    page_name: The wiki page name.
  61   * $data[3]    rev: The page revision, false for current wiki pages.
  62   *
  63   * @author Ben Coburn <btcoburn@silicodon.net>
  64   *
  65   * @param string   $file filename
  66   * @param string   $id page id
  67   * @param bool|int $rev revision timestamp
  68   * @return string
  69   */
  70  function io_readWikiPage($file, $id, $rev=false) {
  71      if (empty($rev)) { $rev = false; }
  72      $data = array(array($file, true), getNS($id), noNS($id), $rev);
  73      return Event::createAndTrigger('IO_WIKIPAGE_READ', $data, '_io_readWikiPage_action', false);
  74  }
  75  
  76  /**
  77   * Callback adapter for io_readFile().
  78   *
  79   * @author Ben Coburn <btcoburn@silicodon.net>
  80   *
  81   * @param array $data event data
  82   * @return string
  83   */
  84  function _io_readWikiPage_action($data) {
  85      if (is_array($data) && is_array($data[0]) && count($data[0])===2) {
  86          return call_user_func_array('io_readFile', $data[0]);
  87      } else {
  88          return ''; //callback error
  89      }
  90  }
  91  
  92  /**
  93   * Returns content of $file as cleaned string.
  94   *
  95   * Uses gzip if extension is .gz
  96   *
  97   * If you want to use the returned value in unserialize
  98   * be sure to set $clean to false!
  99   *
 100   * @author  Andreas Gohr <andi@splitbrain.org>
 101   *
 102   * @param string $file  filename
 103   * @param bool   $clean
 104   * @return string|bool the file contents or false on error
 105   */
 106  function io_readFile($file,$clean=true){
 107      $ret = '';
 108      if(file_exists($file)){
 109          if(substr($file,-3) == '.gz'){
 110              if(!DOKU_HAS_GZIP) return false;
 111              $ret = gzfile($file);
 112              if(is_array($ret)) $ret = join('', $ret);
 113          }else if(substr($file,-4) == '.bz2'){
 114              if(!DOKU_HAS_BZIP) return false;
 115              $ret = bzfile($file);
 116          }else{
 117              $ret = file_get_contents($file);
 118          }
 119      }
 120      if($ret === null) return false;
 121      if($ret !== false && $clean){
 122          return cleanText($ret);
 123      }else{
 124          return $ret;
 125      }
 126  }
 127  /**
 128   * Returns the content of a .bz2 compressed file as string
 129   *
 130   * @author marcel senf <marcel@rucksackreinigung.de>
 131   * @author  Andreas Gohr <andi@splitbrain.org>
 132   *
 133   * @param string $file filename
 134   * @param bool   $array return array of lines
 135   * @return string|array|bool content or false on error
 136   */
 137  function bzfile($file, $array=false) {
 138      $bz = bzopen($file,"r");
 139      if($bz === false) return false;
 140  
 141      if($array) $lines = array();
 142      $str = '';
 143      while (!feof($bz)) {
 144          //8192 seems to be the maximum buffersize?
 145          $buffer = bzread($bz,8192);
 146          if(($buffer === false) || (bzerrno($bz) !== 0)) {
 147              return false;
 148          }
 149          $str = $str . $buffer;
 150          if($array) {
 151              $pos = strpos($str, "\n");
 152              while($pos !== false) {
 153                  $lines[] = substr($str, 0, $pos+1);
 154                  $str = substr($str, $pos+1);
 155                  $pos = strpos($str, "\n");
 156              }
 157          }
 158      }
 159      bzclose($bz);
 160      if($array) {
 161          if($str !== '') $lines[] = $str;
 162          return $lines;
 163      }
 164      return $str;
 165  }
 166  
 167  /**
 168   * Used to write out a DokuWiki page to file, and send IO_WIKIPAGE_WRITE events.
 169   *
 170   * This generates an action event and delegates to io_saveFile().
 171   * Action plugins are allowed to modify the page content in transit.
 172   * The file path should not be changed.
 173   * (The append parameter is set to false.)
 174   *
 175   * Event data:
 176   * $data[0]    The raw arguments for io_saveFile as an array.
 177   * $data[1]    ns: The colon separated namespace path minus the trailing page name. (false if root ns)
 178   * $data[2]    page_name: The wiki page name.
 179   * $data[3]    rev: The page revision, false for current wiki pages.
 180   *
 181   * @author Ben Coburn <btcoburn@silicodon.net>
 182   *
 183   * @param string $file      filename
 184   * @param string $content
 185   * @param string $id        page id
 186   * @param int|bool $rev timestamp of revision
 187   * @return bool
 188   */
 189  function io_writeWikiPage($file, $content, $id, $rev=false) {
 190      if (empty($rev)) { $rev = false; }
 191      if ($rev===false) { io_createNamespace($id); } // create namespaces as needed
 192      $data = array(array($file, $content, false), getNS($id), noNS($id), $rev);
 193      return Event::createAndTrigger('IO_WIKIPAGE_WRITE', $data, '_io_writeWikiPage_action', false);
 194  }
 195  
 196  /**
 197   * Callback adapter for io_saveFile().
 198   * @author Ben Coburn <btcoburn@silicodon.net>
 199   *
 200   * @param array $data event data
 201   * @return bool
 202   */
 203  function _io_writeWikiPage_action($data) {
 204      if (is_array($data) && is_array($data[0]) && count($data[0])===3) {
 205          $ok = call_user_func_array('io_saveFile', $data[0]);
 206          // for attic files make sure the file has the mtime of the revision
 207          if($ok && is_int($data[3]) && $data[3] > 0) {
 208              @touch($data[0][0], $data[3]);
 209          }
 210          return $ok;
 211      } else {
 212          return false; //callback error
 213      }
 214  }
 215  
 216  /**
 217   * Internal function to save contents to a file.
 218   *
 219   * @author  Andreas Gohr <andi@splitbrain.org>
 220   *
 221   * @param string $file filename path to file
 222   * @param string $content
 223   * @param bool   $append
 224   * @return bool true on success, otherwise false
 225   */
 226  function _io_saveFile($file, $content, $append) {
 227      global $conf;
 228      $mode = ($append) ? 'ab' : 'wb';
 229      $fileexists = file_exists($file);
 230  
 231      if(substr($file,-3) == '.gz'){
 232          if(!DOKU_HAS_GZIP) return false;
 233          $fh = @gzopen($file,$mode.'9');
 234          if(!$fh) return false;
 235          gzwrite($fh, $content);
 236          gzclose($fh);
 237      }else if(substr($file,-4) == '.bz2'){
 238          if(!DOKU_HAS_BZIP) return false;
 239          if($append) {
 240              $bzcontent = bzfile($file);
 241              if($bzcontent === false) return false;
 242              $content = $bzcontent.$content;
 243          }
 244          $fh = @bzopen($file,'w');
 245          if(!$fh) return false;
 246          bzwrite($fh, $content);
 247          bzclose($fh);
 248      }else{
 249          $fh = @fopen($file,$mode);
 250          if(!$fh) return false;
 251          fwrite($fh, $content);
 252          fclose($fh);
 253      }
 254  
 255      if(!$fileexists and !empty($conf['fperm'])) chmod($file, $conf['fperm']);
 256      return true;
 257  }
 258  
 259  /**
 260   * Saves $content to $file.
 261   *
 262   * If the third parameter is set to true the given content
 263   * will be appended.
 264   *
 265   * Uses gzip if extension is .gz
 266   * and bz2 if extension is .bz2
 267   *
 268   * @author  Andreas Gohr <andi@splitbrain.org>
 269   *
 270   * @param string $file filename path to file
 271   * @param string $content
 272   * @param bool   $append
 273   * @return bool true on success, otherwise false
 274   */
 275  function io_saveFile($file, $content, $append=false) {
 276      io_makeFileDir($file);
 277      io_lock($file);
 278      if(!_io_saveFile($file, $content, $append)) {
 279          msg("Writing $file failed",-1);
 280          io_unlock($file);
 281          return false;
 282      }
 283      io_unlock($file);
 284      return true;
 285  }
 286  
 287  /**
 288   * Replace one or more occurrences of a line in a file.
 289   *
 290   * The default, when $maxlines is 0 is to delete all matching lines then append a single line.
 291   * A regex that matches any part of the line will remove the entire line in this mode.
 292   * Captures in $newline are not available.
 293   *
 294   * Otherwise each line is matched and replaced individually, up to the first $maxlines lines
 295   * or all lines if $maxlines is -1. If $regex is true then captures can be used in $newline.
 296   *
 297   * Be sure to include the trailing newline in $oldline when replacing entire lines.
 298   *
 299   * Uses gzip if extension is .gz
 300   * and bz2 if extension is .bz2
 301   *
 302   * @author Steven Danz <steven-danz@kc.rr.com>
 303   * @author Christopher Smith <chris@jalakai.co.uk>
 304   * @author Patrick Brown <ptbrown@whoopdedo.org>
 305   *
 306   * @param string $file     filename
 307   * @param string $oldline  exact linematch to remove
 308   * @param string $newline  new line to insert
 309   * @param bool   $regex    use regexp?
 310   * @param int    $maxlines number of occurrences of the line to replace
 311   * @return bool true on success
 312   */
 313  function io_replaceInFile($file, $oldline, $newline, $regex=false, $maxlines=0) {
 314      if ((string)$oldline === '') {
 315          trigger_error('$oldline parameter cannot be empty in io_replaceInFile()', E_USER_WARNING);
 316          return false;
 317      }
 318  
 319      if (!file_exists($file)) return true;
 320  
 321      io_lock($file);
 322  
 323      // load into array
 324      if(substr($file,-3) == '.gz'){
 325          if(!DOKU_HAS_GZIP) return false;
 326          $lines = gzfile($file);
 327      }else if(substr($file,-4) == '.bz2'){
 328          if(!DOKU_HAS_BZIP) return false;
 329          $lines = bzfile($file, true);
 330      }else{
 331          $lines = file($file);
 332      }
 333  
 334      // make non-regexes into regexes
 335      $pattern = $regex ? $oldline : '/^'.preg_quote($oldline,'/').'$/';
 336      $replace = $regex ? $newline : addcslashes($newline, '\$');
 337  
 338      // remove matching lines
 339      if ($maxlines > 0) {
 340          $count = 0;
 341          $matched = 0;
 342          foreach($lines as $i => $line) {
 343              if($count >= $maxlines) break;
 344              // $matched will be set to 0|1 depending on whether pattern is matched and line replaced
 345              $lines[$i] = preg_replace($pattern, $replace, $line, -1, $matched);
 346              if ($matched) $count++;
 347          }
 348      } else if ($maxlines == 0) {
 349          $lines = preg_grep($pattern, $lines, PREG_GREP_INVERT);
 350  
 351          if ((string)$newline !== ''){
 352              $lines[] = $newline;
 353          }
 354      } else {
 355          $lines = preg_replace($pattern, $replace, $lines);
 356      }
 357  
 358      if(count($lines)){
 359          if(!_io_saveFile($file, join('',$lines), false)) {
 360              msg("Removing content from $file failed",-1);
 361              io_unlock($file);
 362              return false;
 363          }
 364      }else{
 365          @unlink($file);
 366      }
 367  
 368      io_unlock($file);
 369      return true;
 370  }
 371  
 372  /**
 373   * Delete lines that match $badline from $file.
 374   *
 375   * Be sure to include the trailing newline in $badline
 376   *
 377   * @author Patrick Brown <ptbrown@whoopdedo.org>
 378   *
 379   * @param string $file    filename
 380   * @param string $badline exact linematch to remove
 381   * @param bool   $regex   use regexp?
 382   * @return bool true on success
 383   */
 384  function io_deleteFromFile($file,$badline,$regex=false){
 385      return io_replaceInFile($file,$badline,null,$regex,0);
 386  }
 387  
 388  /**
 389   * Tries to lock a file
 390   *
 391   * Locking is only done for io_savefile and uses directories
 392   * inside $conf['lockdir']
 393   *
 394   * It waits maximal 3 seconds for the lock, after this time
 395   * the lock is assumed to be stale and the function goes on
 396   *
 397   * @author Andreas Gohr <andi@splitbrain.org>
 398   *
 399   * @param string $file filename
 400   */
 401  function io_lock($file){
 402      global $conf;
 403  
 404      $lockDir = $conf['lockdir'].'/'.md5($file);
 405      @ignore_user_abort(1);
 406  
 407      $timeStart = time();
 408      do {
 409          //waited longer than 3 seconds? -> stale lock
 410          if ((time() - $timeStart) > 3) break;
 411          $locked = @mkdir($lockDir, $conf['dmode']);
 412          if($locked){
 413              if(!empty($conf['dperm'])) chmod($lockDir, $conf['dperm']);
 414              break;
 415          }
 416          usleep(50);
 417      } while ($locked === false);
 418  }
 419  
 420  /**
 421   * Unlocks a file
 422   *
 423   * @author Andreas Gohr <andi@splitbrain.org>
 424   *
 425   * @param string $file filename
 426   */
 427  function io_unlock($file){
 428      global $conf;
 429  
 430      $lockDir = $conf['lockdir'].'/'.md5($file);
 431      @rmdir($lockDir);
 432      @ignore_user_abort(0);
 433  }
 434  
 435  /**
 436   * Create missing namespace directories and send the IO_NAMESPACE_CREATED events
 437   * in the order of directory creation. (Parent directories first.)
 438   *
 439   * Event data:
 440   * $data[0]    ns: The colon separated namespace path minus the trailing page name.
 441   * $data[1]    ns_type: 'pages' or 'media' namespace tree.
 442   *
 443   * @author Ben Coburn <btcoburn@silicodon.net>
 444   *
 445   * @param string $id page id
 446   * @param string $ns_type 'pages' or 'media'
 447   */
 448  function io_createNamespace($id, $ns_type='pages') {
 449      // verify ns_type
 450      $types = array('pages'=>'wikiFN', 'media'=>'mediaFN');
 451      if (!isset($types[$ns_type])) {
 452          trigger_error('Bad $ns_type parameter for io_createNamespace().');
 453          return;
 454      }
 455      // make event list
 456      $missing = array();
 457      $ns_stack = explode(':', $id);
 458      $ns = $id;
 459      $tmp = dirname( $file = call_user_func($types[$ns_type], $ns) );
 460      while (!@is_dir($tmp) && !(file_exists($tmp) && !is_dir($tmp))) {
 461          array_pop($ns_stack);
 462          $ns = implode(':', $ns_stack);
 463          if (strlen($ns)==0) { break; }
 464          $missing[] = $ns;
 465          $tmp = dirname(call_user_func($types[$ns_type], $ns));
 466      }
 467      // make directories
 468      io_makeFileDir($file);
 469      // send the events
 470      $missing = array_reverse($missing); // inside out
 471      foreach ($missing as $ns) {
 472          $data = array($ns, $ns_type);
 473          Event::createAndTrigger('IO_NAMESPACE_CREATED', $data);
 474      }
 475  }
 476  
 477  /**
 478   * Create the directory needed for the given file
 479   *
 480   * @author  Andreas Gohr <andi@splitbrain.org>
 481   *
 482   * @param string $file file name
 483   */
 484  function io_makeFileDir($file){
 485      $dir = dirname($file);
 486      if(!@is_dir($dir)){
 487          io_mkdir_p($dir) || msg("Creating directory $dir failed",-1);
 488      }
 489  }
 490  
 491  /**
 492   * Creates a directory hierachy.
 493   *
 494   * @link    http://php.net/manual/en/function.mkdir.php
 495   * @author  <saint@corenova.com>
 496   * @author  Andreas Gohr <andi@splitbrain.org>
 497   *
 498   * @param string $target filename
 499   * @return bool|int|string
 500   */
 501  function io_mkdir_p($target){
 502      global $conf;
 503      if (@is_dir($target)||empty($target)) return 1; // best case check first
 504      if (file_exists($target) && !is_dir($target)) return 0;
 505      //recursion
 506      if (io_mkdir_p(substr($target,0,strrpos($target,'/')))){
 507          $ret = @mkdir($target,$conf['dmode']); // crawl back up & create dir tree
 508          if($ret && !empty($conf['dperm'])) chmod($target, $conf['dperm']);
 509          return $ret;
 510      }
 511      return 0;
 512  }
 513  
 514  /**
 515   * Recursively delete a directory
 516   *
 517   * @author Andreas Gohr <andi@splitbrain.org>
 518   * @param string $path
 519   * @param bool   $removefiles defaults to false which will delete empty directories only
 520   * @return bool
 521   */
 522  function io_rmdir($path, $removefiles = false) {
 523      if(!is_string($path) || $path == "") return false;
 524      if(!file_exists($path)) return true; // it's already gone or was never there, count as success
 525  
 526      if(is_dir($path) && !is_link($path)) {
 527          $dirs  = array();
 528          $files = array();
 529  
 530          if(!$dh = @opendir($path)) return false;
 531          while(false !== ($f = readdir($dh))) {
 532              if($f == '..' || $f == '.') continue;
 533  
 534              // collect dirs and files first
 535              if(is_dir("$path/$f") && !is_link("$path/$f")) {
 536                  $dirs[] = "$path/$f";
 537              } else if($removefiles) {
 538                  $files[] = "$path/$f";
 539              } else {
 540                  return false; // abort when non empty
 541              }
 542  
 543          }
 544          closedir($dh);
 545  
 546          // now traverse into  directories first
 547          foreach($dirs as $dir) {
 548              if(!io_rmdir($dir, $removefiles)) return false; // abort on any error
 549          }
 550  
 551          // now delete files
 552          foreach($files as $file) {
 553              if(!@unlink($file)) return false; //abort on any error
 554          }
 555  
 556          // remove self
 557          return @rmdir($path);
 558      } else if($removefiles) {
 559          return @unlink($path);
 560      }
 561      return false;
 562  }
 563  
 564  /**
 565   * Creates a unique temporary directory and returns
 566   * its path.
 567   *
 568   * @author Michael Klier <chi@chimeric.de>
 569   *
 570   * @return false|string path to new directory or false
 571   */
 572  function io_mktmpdir() {
 573      global $conf;
 574  
 575      $base = $conf['tmpdir'];
 576      $dir  = md5(uniqid(mt_rand(), true));
 577      $tmpdir = $base.'/'.$dir;
 578  
 579      if(io_mkdir_p($tmpdir)) {
 580          return($tmpdir);
 581      } else {
 582          return false;
 583      }
 584  }
 585  
 586  /**
 587   * downloads a file from the net and saves it
 588   *
 589   * if $useAttachment is false,
 590   * - $file is the full filename to save the file, incl. path
 591   * - if successful will return true, false otherwise
 592   *
 593   * if $useAttachment is true,
 594   * - $file is the directory where the file should be saved
 595   * - if successful will return the name used for the saved file, false otherwise
 596   *
 597   * @author Andreas Gohr <andi@splitbrain.org>
 598   * @author Chris Smith <chris@jalakai.co.uk>
 599   *
 600   * @param string $url           url to download
 601   * @param string $file          path to file or directory where to save
 602   * @param bool   $useAttachment true: try to use name of download, uses otherwise $defaultName
 603   *                              false: uses $file as path to file
 604   * @param string $defaultName   fallback for if using $useAttachment
 605   * @param int    $maxSize       maximum file size
 606   * @return bool|string          if failed false, otherwise true or the name of the file in the given dir
 607   */
 608  function io_download($url,$file,$useAttachment=false,$defaultName='',$maxSize=2097152){
 609      global $conf;
 610      $http = new DokuHTTPClient();
 611      $http->max_bodysize = $maxSize;
 612      $http->timeout = 25; //max. 25 sec
 613      $http->keep_alive = false; // we do single ops here, no need for keep-alive
 614  
 615      $data = $http->get($url);
 616      if(!$data) return false;
 617  
 618      $name = '';
 619      if ($useAttachment) {
 620          if (isset($http->resp_headers['content-disposition'])) {
 621              $content_disposition = $http->resp_headers['content-disposition'];
 622              $match=array();
 623              if (is_string($content_disposition) &&
 624                      preg_match('/attachment;\s*filename\s*=\s*"([^"]*)"/i', $content_disposition, $match)) {
 625  
 626                  $name = \dokuwiki\Utf8\PhpString::basename($match[1]);
 627              }
 628  
 629          }
 630  
 631          if (!$name) {
 632              if (!$defaultName) return false;
 633              $name = $defaultName;
 634          }
 635  
 636          $file = $file.$name;
 637      }
 638  
 639      $fileexists = file_exists($file);
 640      $fp = @fopen($file,"w");
 641      if(!$fp) return false;
 642      fwrite($fp,$data);
 643      fclose($fp);
 644      if(!$fileexists and $conf['fperm']) chmod($file, $conf['fperm']);
 645      if ($useAttachment) return $name;
 646      return true;
 647  }
 648  
 649  /**
 650   * Windows compatible rename
 651   *
 652   * rename() can not overwrite existing files on Windows
 653   * this function will use copy/unlink instead
 654   *
 655   * @param string $from
 656   * @param string $to
 657   * @return bool succes or fail
 658   */
 659  function io_rename($from,$to){
 660      global $conf;
 661      if(!@rename($from,$to)){
 662          if(@copy($from,$to)){
 663              if($conf['fperm']) chmod($to, $conf['fperm']);
 664              @unlink($from);
 665              return true;
 666          }
 667          return false;
 668      }
 669      return true;
 670  }
 671  
 672  /**
 673   * Runs an external command with input and output pipes.
 674   * Returns the exit code from the process.
 675   *
 676   * @author Tom N Harris <tnharris@whoopdedo.org>
 677   *
 678   * @param string $cmd
 679   * @param string $input  input pipe
 680   * @param string $output output pipe
 681   * @return int exit code from process
 682   */
 683  function io_exec($cmd, $input, &$output){
 684      $descspec = array(
 685              0=>array("pipe","r"),
 686              1=>array("pipe","w"),
 687              2=>array("pipe","w"));
 688      $ph = proc_open($cmd, $descspec, $pipes);
 689      if(!$ph) return -1;
 690      fclose($pipes[2]); // ignore stderr
 691      fwrite($pipes[0], $input);
 692      fclose($pipes[0]);
 693      $output = stream_get_contents($pipes[1]);
 694      fclose($pipes[1]);
 695      return proc_close($ph);
 696  }
 697  
 698  /**
 699   * Search a file for matching lines
 700   *
 701   * This is probably not faster than file()+preg_grep() but less
 702   * memory intensive because not the whole file needs to be loaded
 703   * at once.
 704   *
 705   * @author Andreas Gohr <andi@splitbrain.org>
 706   * @param  string $file    The file to search
 707   * @param  string $pattern PCRE pattern
 708   * @param  int    $max     How many lines to return (0 for all)
 709   * @param  bool   $backref When true returns array with backreferences instead of lines
 710   * @return array matching lines or backref, false on error
 711   */
 712  function io_grep($file,$pattern,$max=0,$backref=false){
 713      $fh = @fopen($file,'r');
 714      if(!$fh) return false;
 715      $matches = array();
 716  
 717      $cnt  = 0;
 718      $line = '';
 719      while (!feof($fh)) {
 720          $line .= fgets($fh, 4096);  // read full line
 721          if(substr($line,-1) != "\n") continue;
 722  
 723          // check if line matches
 724          if(preg_match($pattern,$line,$match)){
 725              if($backref){
 726                  $matches[] = $match;
 727              }else{
 728                  $matches[] = $line;
 729              }
 730              $cnt++;
 731          }
 732          if($max && $max == $cnt) break;
 733          $line = '';
 734      }
 735      fclose($fh);
 736      return $matches;
 737  }
 738  
 739  
 740  /**
 741   * Get size of contents of a file, for a compressed file the uncompressed size
 742   * Warning: reading uncompressed size of content of bz-files requires uncompressing
 743   *
 744   * @author  Gerrit Uitslag <klapinklapin@gmail.com>
 745   *
 746   * @param string $file filename path to file
 747   * @return int size of file
 748   */
 749  function io_getSizeFile($file) {
 750      if (!file_exists($file)) return 0;
 751  
 752      if(substr($file,-3) == '.gz'){
 753          $fp = @fopen($file, "rb");
 754          if($fp === false) return 0;
 755  
 756          fseek($fp, -4, SEEK_END);
 757          $buffer = fread($fp, 4);
 758          fclose($fp);
 759          $array = unpack("V", $buffer);
 760          $uncompressedsize = end($array);
 761      }else if(substr($file,-4) == '.bz2'){
 762          if(!DOKU_HAS_BZIP) return 0;
 763  
 764          $bz = bzopen($file,"r");
 765          if($bz === false) return 0;
 766  
 767          $uncompressedsize = 0;
 768          while (!feof($bz)) {
 769              //8192 seems to be the maximum buffersize?
 770              $buffer = bzread($bz,8192);
 771              if(($buffer === false) || (bzerrno($bz) !== 0)) {
 772                  return 0;
 773              }
 774              $uncompressedsize += strlen($buffer);
 775          }
 776      }else{
 777          $uncompressedsize = filesize($file);
 778      }
 779  
 780      return $uncompressedsize;
 781   }