lib/filelib.php

   1 <?php //$Id$
   2
   3 define('BYTESERVING_BOUNDARY', 's1k2o3d4a5k6s7'); //unique string constant
   4
   5 function get_file_url($path, $options=null, $type='coursefile') {
   6     global $CFG;
   7
   8     $path = str_replace('//', '/', $path);
   9     $path = trim($path, '/'); // no leading and trailing slashes
  10
  11     // type of file
  12     switch ($type) {
  13        case 'questionfile':
  14             $url = $CFG->wwwroot."/question/exportfile.php";
  15             break;
  16        case 'rssfile':
  17             $url = $CFG->wwwroot."/rss/file.php";
  18             break;
  19         case 'user':
  20             $url = $CFG->wwwroot."/user/pix.php";
  21             break;
  22         case 'usergroup':
  23             $url = $CFG->wwwroot."/user/pixgroup.php";
  24             break;
  25         case 'httpscoursefile':
  26             $url = $CFG->httpswwwroot."/file.php";
  27             break;
  28          case 'coursefile':
  29         default:
  30             $url = $CFG->wwwroot."/file.php";
  31     }
  32
  33     if ($CFG->slasharguments) {
  34         $parts = explode('/', $path);
  35         $parts = array_map('rawurlencode', $parts);
  36         $path  = implode('/', $parts);
  37         $ffurl = $url.'/'.$path;
  38         $separator = '?';
  39     } else {
  40         $path = rawurlencode('/'.$path);
  41         $ffurl = $url.'?file='.$path;
  42         $separator = '&amp;';
  43     }
  44
  45     if ($options) {
  46         foreach ($options as $name=>$value) {
  47             $ffurl = $ffurl.$separator.$name.'='.$value;
  48             $separator = '&amp;';
  49         }
  50     }
  51
  52     return $ffurl;
  53 }
  54
  55 /**
  56  * Fetches content of file from Internet (using proxy if defined). Uses cURL extension if present.
  57  * Due to security concerns only downloads from http(s) sources are supported.
  58  *
  59  * @param string $url file url starting with http(s)://
  60  * @param array $headers http headers, null if none. If set, should be an
  61  *   associative array of header name => value pairs.
  62  * @param array $postdata array means use POST request with given parameters
  63  * @param bool $fullresponse return headers, responses, etc in a similar way snoopy does
  64  *   (if false, just returns content)
  65  * @param int $timeout timeout for complete download process including all file transfer
  66  *   (default 5 minutes)
  67  * @param int $connecttimeout timeout for connection to server; this is the timeout that
  68  *   usually happens if the remote server is completely down (default 20 seconds);
  69  *   may not work when using proxy
  70  * @param bool $skipcertverify If true, the peer's SSL certificate will not be checked. Only use this when already in a trusted location.
  71  * @return mixed false if request failed or content of the file as string if ok.
  72  */
  73 function download_file_content($url, $headers=null, $postdata=null, $fullresponse=false, $timeout=300, $connecttimeout=20, $skipcertverify=false) {
  74     global $CFG;
  75
  76     // some extra security
  77     $newlines = array("\r", "\n");
  78     if (is_array($headers) ) {
  79         foreach ($headers as $key => $value) {
  80             $headers[$key] = str_replace($newlines, '', $value);
  81         }
  82     }
  83     $url = str_replace($newlines, '', $url);
  84     if (!preg_match('|^https?://|i', $url)) {
  85         if ($fullresponse) {
  86             $response = new object();
  87             $response->status        = 0;
  88             $response->headers       = array();
  89             $response->response_code = 'Invalid protocol specified in url';
  90             $response->results       = '';
  91             $response->error         = 'Invalid protocol specified in url';
  92             return $response;
  93         } else {
  94             return false;
  95         }
  96     }
  97
  98
  99     if (!extension_loaded('curl') or ($ch = curl_init($url)) === false) {
 100         require_once($CFG->libdir.'/snoopy/Snoopy.class.inc');
 101         $snoopy = new Snoopy();
 102         $snoopy->read_timeout = $timeout;
 103         $snoopy->_fp_timeout  = $connecttimeout;
 104         $snoopy->proxy_host   = $CFG->proxyhost;
 105         $snoopy->proxy_port   = $CFG->proxyport;
 106         if (!empty($CFG->proxyuser) and !empty($CFG->proxypassword)) {
 107             // this will probably fail, but let's try it anyway
 108             $snoopy->proxy_user     = $CFG->proxyuser;
 109             $snoopy->proxy_password = $CFG->proxypassword;
 110         }
 111         if (is_array($headers) ) {
 112             $client->rawheaders = $headers;
 113         }
 114
 115         if (is_array($postdata)) {
 116             $fetch = @$snoopy->fetch($url, $postdata); // use more specific debug code bellow
 117         } else {
 118             $fetch = @$snoopy->fetch($url); // use more specific debug code bellow
 119         }
 120
 121         if ($fetch) {
 122             if ($fullresponse) {
 123                 //fix header line endings
 124                 foreach ($snoopy->headers as $key=>$unused) {
 125                     $snoopy->headers[$key] = trim($snoopy->headers[$key]);
 126                 }
 127                 $response = new object();
 128                 $response->status        = $snoopy->status;
 129                 $response->headers       = $snoopy->headers;
 130                 $response->response_code = trim($snoopy->response_code);
 131                 $response->results       = $snoopy->results;
 132                 $response->error         = $snoopy->error;
 133                 return $response;
 134
 135             } else if ($snoopy->status != 200) {
 136                 debugging("Snoopy request for \"$url\" failed, http response code: ".$snoopy->response_code, DEBUG_ALL);
 137                 return false;
 138
 139             } else {
 140                 return $snoopy->results;
 141             }
 142         } else {
 143             if ($fullresponse) {
 144                 $response = new object();
 145                 $response->status        = $snoopy->status;
 146                 $response->headers       = array();
 147                 $response->response_code = $snoopy->response_code;
 148                 $response->results       = '';
 149                 $response->error         = $snoopy->error;
 150                 return $response;
 151             } else {
 152                 debugging("Snoopy request for \"$url\" failed with: ".$snoopy->error, DEBUG_ALL);
 153                 return false;
 154             }
 155         }
 156     }
 157
 158     // set extra headers
 159     if (is_array($headers) ) {
 160         $headers2 = array();
 161         foreach ($headers as $key => $value) {
 162             $headers2[] = "$key: $value";
 163         }
 164         curl_setopt($ch, CURLOPT_HTTPHEADER, $headers2);
 165     }
 166
 167
 168     if ($skipcertverify) {
 169         curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
 170     }
 171
 172     // use POST if requested
 173     if (is_array($postdata)) {
 174         foreach ($postdata as $k=>$v) {
 175             $postdata[$k] = urlencode($k).'='.urlencode($v);
 176         }
 177         $postdata = implode('&', $postdata);
 178         curl_setopt($ch, CURLOPT_POST, true);
 179         curl_setopt($ch, CURLOPT_POSTFIELDS, $postdata);
 180     }
 181
 182     curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
 183     curl_setopt($ch, CURLOPT_HEADER, true);
 184     curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $connecttimeout);
 185     curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
 186     if (!ini_get('open_basedir') and !ini_get('safe_mode')) {
 187         // TODO: add version test for '7.10.5'
 188         curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
 189         curl_setopt($ch, CURLOPT_MAXREDIRS, 5);
 190     }
 191
 192     if (!empty($CFG->proxyhost)) {
 193         // SOCKS supported in PHP5 only
 194         if (!empty($CFG->proxytype) and ($CFG->proxytype == 'SOCKS5')) {
 195             if (defined('CURLPROXY_SOCKS5')) {
 196                 curl_setopt($ch, CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
 197             } else {
 198                 curl_close($ch);
 199                 if ($fullresponse) {
 200                     $response = new object();
 201                     $response->status        = '0';
 202                     $response->headers       = array();
 203                     $response->response_code = 'SOCKS5 proxy is not supported in PHP4';
 204                     $response->results       = '';
 205                     $response->error         = 'SOCKS5 proxy is not supported in PHP4';
 206                     return $response;
 207                 } else {
 208                     debugging("SOCKS5 proxy is not supported in PHP4.", DEBUG_ALL);
 209                     return false;
 210                 }
 211             }
 212         }
 213
 214         curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, false);
 215
 216         if (empty($CFG->proxyport)) {
 217             curl_setopt($ch, CURLOPT_PROXY, $CFG->proxyhost);
 218         } else {
 219             curl_setopt($ch, CURLOPT_PROXY, $CFG->proxyhost.':'.$CFG->proxyport);
 220         }
 221
 222         if (!empty($CFG->proxyuser) and !empty($CFG->proxypassword)) {
 223             curl_setopt($ch, CURLOPT_PROXYUSERPWD, $CFG->proxyuser.':'.$CFG->proxypassword);
 224             if (defined('CURLOPT_PROXYAUTH')) {
 225                 // any proxy authentication if PHP 5.1
 226                 curl_setopt($ch, CURLOPT_PROXYAUTH, CURLAUTH_BASIC | CURLAUTH_NTLM);
 227             }
 228         }
 229     }
 230
 231     $data = curl_exec($ch);
 232
 233     // try to detect encoding problems
 234     if ((curl_errno($ch) == 23 or curl_errno($ch) == 61) and defined('CURLOPT_ENCODING')) {
 235         curl_setopt($ch, CURLOPT_ENCODING, 'none');
 236         $data = curl_exec($ch);
 237     }
 238
 239     if (curl_errno($ch)) {
 240         $error    = curl_error($ch);
 241         $error_no = curl_errno($ch);
 242         curl_close($ch);
 243
 244         if ($fullresponse) {
 245             $response = new object();
 246             if ($error_no == 28) {
 247                 $response->status    = '-100'; // mimic snoopy
 248             } else {
 249                 $response->status    = '0';
 250             }
 251             $response->headers       = array();
 252             $response->response_code = $error;
 253             $response->results       = '';
 254             $response->error         = $error;
 255             return $response;
 256         } else {
 257             debugging("cURL request for \"$url\" failed with: $error ($error_no)", DEBUG_ALL);
 258             return false;
 259         }
 260
 261     } else {
 262         $info = curl_getinfo($ch);
 263         curl_close($ch);
 264
 265         if (empty($info['http_code'])) {
 266             // for security reasons we support only true http connections (Location: file:// exploit prevention)
 267             $response = new object();
 268             $response->status        = '0';
 269             $response->headers       = array();
 270             $response->response_code = 'Unknown cURL error';
 271             $response->results       = ''; // do NOT change this!
 272             $response->error         = 'Unknown cURL error';
 273
 274         } else {
 275             // strip redirect headers and get headers array and content
 276             $data = explode("\r\n\r\n", $data, $info['redirect_count'] + 2);
 277             $results = array_pop($data);
 278             $headers = array_pop($data);
 279             $headers = explode("\r\n", trim($headers));
 280
 281             $response = new object();;
 282             $response->status        = (string)$info['http_code'];
 283             $response->headers       = $headers;
 284             $response->response_code = $headers[0];
 285             $response->results       = $results;
 286             $response->error         = '';
 287         }
 288
 289         if ($fullresponse) {
 290             return $response;
 291         } else if ($info['http_code'] != 200) {
 292             debugging("cURL request for \"$url\" failed, HTTP response code: ".$response->response_code, DEBUG_ALL);
 293             return false;
 294         } else {
 295             return $response->results;
 296         }
 297     }
 298 }
 299
 300 /**
 301  * @return List of information about file types based on extensions.
 302  *   Associative array of extension (lower-case) to associative array
 303  *   from 'element name' to data. Current element names are 'type' and 'icon'.
 304  *   Unknown types should use the 'xxx' entry which includes defaults.
 305  */
 306 function get_mimetypes_array() {
 307     return array (
 308         'xxx'  => array ('type'=>'document/unknown', 'icon'=>'unknown.gif'),
 309         '3gp'  => array ('type'=>'video/quicktime', 'icon'=>'video.gif'),
 310         'ai'   => array ('type'=>'application/postscript', 'icon'=>'image.gif'),
 311         'aif'  => array ('type'=>'audio/x-aiff', 'icon'=>'audio.gif'),
 312         'aiff' => array ('type'=>'audio/x-aiff', 'icon'=>'audio.gif'),
 313         'aifc' => array ('type'=>'audio/x-aiff', 'icon'=>'audio.gif'),
 314         'applescript'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 315         'asc'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 316         'asm'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 317         'au'   => array ('type'=>'audio/au', 'icon'=>'audio.gif'),
 318         'avi'  => array ('type'=>'video/x-ms-wm', 'icon'=>'avi.gif'),
 319         'bmp'  => array ('type'=>'image/bmp', 'icon'=>'image.gif'),
 320         'c'    => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 321         'cct'  => array ('type'=>'shockwave/director', 'icon'=>'flash.gif'),
 322         'cpp'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 323         'cs'   => array ('type'=>'application/x-csh', 'icon'=>'text.gif'),
 324         'css'  => array ('type'=>'text/css', 'icon'=>'text.gif'),
 325         'csv'  => array ('type'=>'text/csv', 'icon'=>'excel.gif'),
 326         'dv'   => array ('type'=>'video/x-dv', 'icon'=>'video.gif'),
 327         'dmg'  => array ('type'=>'application/octet-stream', 'icon'=>'dmg.gif'),
 328         'doc'  => array ('type'=>'application/msword', 'icon'=>'word.gif'),
 329         'docx' => array ('type'=>'application/msword', 'icon'=>'docx.gif'),
 330         'docm' => array ('type'=>'application/msword', 'icon'=>'docm.gif'),
 331         'dotx' => array ('type'=>'application/msword', 'icon'=>'dotx.gif'),
 332         'dcr'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
 333         'dif'  => array ('type'=>'video/x-dv', 'icon'=>'video.gif'),
 334         'dir'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
 335         'dxr'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
 336         'eps'  => array ('type'=>'application/postscript', 'icon'=>'pdf.gif'),
 337         'fdf'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 338         'flv'  => array ('type'=>'video/x-flv', 'icon'=>'video.gif'),
 339         'gif'  => array ('type'=>'image/gif', 'icon'=>'image.gif'),
 340         'gtar' => array ('type'=>'application/x-gtar', 'icon'=>'zip.gif'),
 341         'tgz'  => array ('type'=>'application/g-zip', 'icon'=>'zip.gif'),
 342         'gz'   => array ('type'=>'application/g-zip', 'icon'=>'zip.gif'),
 343         'gzip' => array ('type'=>'application/g-zip', 'icon'=>'zip.gif'),
 344         'h'    => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 345         'hpp'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 346         'hqx'  => array ('type'=>'application/mac-binhex40', 'icon'=>'zip.gif'),
 347         'htc'  => array ('type'=>'text/x-component', 'icon'=>'text.gif'),
 348         'html' => array ('type'=>'text/html', 'icon'=>'html.gif'),
 349         'xhtml'=> array ('type'=>'application/xhtml+xml', 'icon'=>'html.gif'),
 350         'htm'  => array ('type'=>'text/html', 'icon'=>'html.gif'),
 351         'ico'  => array ('type'=>'image/vnd.microsoft.icon', 'icon'=>'image.gif'),
 352         'ics'  => array ('type'=>'text/calendar', 'icon'=>'text.gif'),
 353         'isf'  => array ('type'=>'application/inspiration', 'icon'=>'isf.gif'),
 354         'ist'  => array ('type'=>'application/inspiration.template', 'icon'=>'isf.gif'),
 355         'java' => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 356         'jcb'  => array ('type'=>'text/xml', 'icon'=>'jcb.gif'),
 357         'jcl'  => array ('type'=>'text/xml', 'icon'=>'jcl.gif'),
 358         'jcw'  => array ('type'=>'text/xml', 'icon'=>'jcw.gif'),
 359         'jmt'  => array ('type'=>'text/xml', 'icon'=>'jmt.gif'),
 360         'jmx'  => array ('type'=>'text/xml', 'icon'=>'jmx.gif'),
 361         'jpe'  => array ('type'=>'image/jpeg', 'icon'=>'image.gif'),
 362         'jpeg' => array ('type'=>'image/jpeg', 'icon'=>'image.gif'),
 363         'jpg'  => array ('type'=>'image/jpeg', 'icon'=>'image.gif'),
 364         'jqz'  => array ('type'=>'text/xml', 'icon'=>'jqz.gif'),
 365         'js'   => array ('type'=>'application/x-javascript', 'icon'=>'text.gif'),
 366         'latex'=> array ('type'=>'application/x-latex', 'icon'=>'text.gif'),
 367         'm'    => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 368         'mov'  => array ('type'=>'video/quicktime', 'icon'=>'video.gif'),
 369         'movie'=> array ('type'=>'video/x-sgi-movie', 'icon'=>'video.gif'),
 370         'm3u'  => array ('type'=>'audio/x-mpegurl', 'icon'=>'audio.gif'),
 371         'mp3'  => array ('type'=>'audio/mp3', 'icon'=>'audio.gif'),
 372         'mp4'  => array ('type'=>'video/mp4', 'icon'=>'video.gif'),
 373         'mpeg' => array ('type'=>'video/mpeg', 'icon'=>'video.gif'),
 374         'mpe'  => array ('type'=>'video/mpeg', 'icon'=>'video.gif'),
 375         'mpg'  => array ('type'=>'video/mpeg', 'icon'=>'video.gif'),
 376
 377         'odt'  => array ('type'=>'application/vnd.oasis.opendocument.text', 'icon'=>'odt.gif'),
 378         'ott'  => array ('type'=>'application/vnd.oasis.opendocument.text-template', 'icon'=>'odt.gif'),
 379         'oth'  => array ('type'=>'application/vnd.oasis.opendocument.text-web', 'icon'=>'odt.gif'),
 380         'odm'  => array ('type'=>'application/vnd.oasis.opendocument.text-master', 'icon'=>'odm.gif'),
 381         'odg'  => array ('type'=>'application/vnd.oasis.opendocument.graphics', 'icon'=>'odg.gif'),
 382         'otg'  => array ('type'=>'application/vnd.oasis.opendocument.graphics-template', 'icon'=>'odg.gif'),
 383         'odp'  => array ('type'=>'application/vnd.oasis.opendocument.presentation', 'icon'=>'odp.gif'),
 384         'otp'  => array ('type'=>'application/vnd.oasis.opendocument.presentation-template', 'icon'=>'odp.gif'),
 385         'ods'  => array ('type'=>'application/vnd.oasis.opendocument.spreadsheet', 'icon'=>'ods.gif'),
 386         'ots'  => array ('type'=>'application/vnd.oasis.opendocument.spreadsheet-template', 'icon'=>'ods.gif'),
 387         'odc'  => array ('type'=>'application/vnd.oasis.opendocument.chart', 'icon'=>'odc.gif'),
 388         'odf'  => array ('type'=>'application/vnd.oasis.opendocument.formula', 'icon'=>'odf.gif'),
 389         'odb'  => array ('type'=>'application/vnd.oasis.opendocument.database', 'icon'=>'odb.gif'),
 390         'odi'  => array ('type'=>'application/vnd.oasis.opendocument.image', 'icon'=>'odi.gif'),
 391
 392         'pct'  => array ('type'=>'image/pict', 'icon'=>'image.gif'),
 393         'pdf'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 394         'php'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 395         'pic'  => array ('type'=>'image/pict', 'icon'=>'image.gif'),
 396         'pict' => array ('type'=>'image/pict', 'icon'=>'image.gif'),
 397         'png'  => array ('type'=>'image/png', 'icon'=>'image.gif'),
 398         'pps'  => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'powerpoint.gif'),
 399         'ppt'  => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'powerpoint.gif'),
 400         'pptx' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'pptx.gif'),
 401         'pptm' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'pptm.gif'),
 402         'potx' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'potx.gif'),
 403         'potm' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'potm.gif'),
 404         'ppam' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'ppam.gif'),
 405         'ppsx' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'ppsx.gif'),
 406         'ppsm' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'ppsm.gif'),
 407         'ps'   => array ('type'=>'application/postscript', 'icon'=>'pdf.gif'),
 408         'qt'   => array ('type'=>'video/quicktime', 'icon'=>'video.gif'),
 409         'ra'   => array ('type'=>'audio/x-realaudio', 'icon'=>'audio.gif'),
 410         'ram'  => array ('type'=>'audio/x-pn-realaudio', 'icon'=>'audio.gif'),
 411         'rhb'  => array ('type'=>'text/xml', 'icon'=>'xml.gif'),
 412         'rm'   => array ('type'=>'audio/x-pn-realaudio', 'icon'=>'audio.gif'),
 413         'rtf'  => array ('type'=>'text/rtf', 'icon'=>'text.gif'),
 414         'rtx'  => array ('type'=>'text/richtext', 'icon'=>'text.gif'),
 415         'sh'   => array ('type'=>'application/x-sh', 'icon'=>'text.gif'),
 416         'sit'  => array ('type'=>'application/x-stuffit', 'icon'=>'zip.gif'),
 417         'smi'  => array ('type'=>'application/smil', 'icon'=>'text.gif'),
 418         'smil' => array ('type'=>'application/smil', 'icon'=>'text.gif'),
 419         'sqt'  => array ('type'=>'text/xml', 'icon'=>'xml.gif'),
 420         'svg'  => array ('type'=>'image/svg+xml', 'icon'=>'image.gif'),
 421         'svgz' => array ('type'=>'image/svg+xml', 'icon'=>'image.gif'),
 422         'swa'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
 423         'swf'  => array ('type'=>'application/x-shockwave-flash', 'icon'=>'flash.gif'),
 424         'swfl' => array ('type'=>'application/x-shockwave-flash', 'icon'=>'flash.gif'),
 425
 426         'sxw'  => array ('type'=>'application/vnd.sun.xml.writer', 'icon'=>'odt.gif'),
 427         'stw'  => array ('type'=>'application/vnd.sun.xml.writer.template', 'icon'=>'odt.gif'),
 428         'sxc'  => array ('type'=>'application/vnd.sun.xml.calc', 'icon'=>'odt.gif'),
 429         'stc'  => array ('type'=>'application/vnd.sun.xml.calc.template', 'icon'=>'odt.gif'),
 430         'sxd'  => array ('type'=>'application/vnd.sun.xml.draw', 'icon'=>'odt.gif'),
 431         'std'  => array ('type'=>'application/vnd.sun.xml.draw.template', 'icon'=>'odt.gif'),
 432         'sxi'  => array ('type'=>'application/vnd.sun.xml.impress', 'icon'=>'odt.gif'),
 433         'sti'  => array ('type'=>'application/vnd.sun.xml.impress.template', 'icon'=>'odt.gif'),
 434         'sxg'  => array ('type'=>'application/vnd.sun.xml.writer.global', 'icon'=>'odt.gif'),
 435         'sxm'  => array ('type'=>'application/vnd.sun.xml.math', 'icon'=>'odt.gif'),
 436
 437         'tar'  => array ('type'=>'application/x-tar', 'icon'=>'zip.gif'),
 438         'tif'  => array ('type'=>'image/tiff', 'icon'=>'image.gif'),
 439         'tiff' => array ('type'=>'image/tiff', 'icon'=>'image.gif'),
 440         'tex'  => array ('type'=>'application/x-tex', 'icon'=>'text.gif'),
 441         'texi' => array ('type'=>'application/x-texinfo', 'icon'=>'text.gif'),
 442         'texinfo'  => array ('type'=>'application/x-texinfo', 'icon'=>'text.gif'),
 443         'tsv'  => array ('type'=>'text/tab-separated-values', 'icon'=>'text.gif'),
 444         'txt'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 445         'wav'  => array ('type'=>'audio/wav', 'icon'=>'audio.gif'),
 446         'wmv'  => array ('type'=>'video/x-ms-wmv', 'icon'=>'avi.gif'),
 447         'asf'  => array ('type'=>'video/x-ms-asf', 'icon'=>'avi.gif'),
 448         'xdp'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 449         'xfd'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 450         'xfdf' => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 451         'xls'  => array ('type'=>'application/vnd.ms-excel', 'icon'=>'excel.gif'),
 452         'xlsx' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlsx.gif'),
 453         'xlsm' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlsm.gif'),
 454         'xltx' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xltx.gif'),
 455         'xltm' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xltm.gif'),
 456         'xlsb' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlsb.gif'),
 457         'xlam' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlam.gif'),
 458         'xml'  => array ('type'=>'application/xml', 'icon'=>'xml.gif'),
 459         'xsl'  => array ('type'=>'text/xml', 'icon'=>'xml.gif'),
 460         'zip'  => array ('type'=>'application/zip', 'icon'=>'zip.gif')
 461     );
 462 }
 463
 464 /**
 465  * Obtains information about a filetype based on its extension. Will
 466  * use a default if no information is present about that particular
 467  * extension.
 468  * @param string $element Desired information (usually 'icon'
 469  *   for icon filename or 'type' for MIME type)
 470  * @param string $filename Filename we're looking up
 471  * @return string Requested piece of information from array
 472  */
 473 function mimeinfo($element, $filename) {
 474     static $mimeinfo = null;
 475     if (is_null($mimeinfo)) {
 476         $mimeinfo = get_mimetypes_array();
 477     }
 478
 479     if (eregi('\.([a-z0-9]+)$', $filename, $match)) {
 480         if (isset($mimeinfo[strtolower($match[1])][$element])) {
 481             return $mimeinfo[strtolower($match[1])][$element];
 482         } else {
 483             return $mimeinfo['xxx'][$element];   // By default
 484         }
 485     } else {
 486         return $mimeinfo['xxx'][$element];   // By default
 487     }
 488 }
 489
 490 /**
 491  * Obtains information about a filetype based on the MIME type rather than
 492  * the other way around.
 493  * @param string $element Desired information (usually 'icon')
 494  * @param string $mimetype MIME type we're looking up
 495  * @return string Requested piece of information from array
 496  */
 497 function mimeinfo_from_type($element, $mimetype) {
 498     static $mimeinfo;
 499     $mimeinfo=get_mimetypes_array();
 500
 501     foreach($mimeinfo as $values) {
 502         if($values['type']==$mimetype) {
 503             if(isset($values[$element])) {
 504                 return $values[$element];
 505             }
 506             break;
 507         }
 508     }
 509     return $mimeinfo['xxx'][$element]; // Default
 510 }
 511
 512 /**
 513  * Get information about a filetype based on the icon file.
 514  * @param string $element Desired information (usually 'icon')
 515  * @param string $icon Icon file path.
 516  * @return string Requested piece of information from array
 517  */
 518 function mimeinfo_from_icon($element, $icon) {
 519     static $mimeinfo;
 520     $mimeinfo=get_mimetypes_array();
 521
 522     if (preg_match("/\/(.*)/", $icon, $matches)) {
 523         $icon = $matches[1];
 524     }
 525     $info = $mimeinfo['xxx'][$element]; // Default
 526     foreach($mimeinfo as $values) {
 527         if($values['icon']==$icon) {
 528             if(isset($values[$element])) {
 529                 $info = $values[$element];
 530             }
 531             //No break, for example for 'excel.gif' we don't want 'csv'!
 532         }
 533     }
 534     return $info;
 535 }
 536
 537 /**
 538  * Obtains descriptions for file types (e.g. 'Microsoft Word document') from the
 539  * mimetypes.php language file.
 540  * @param string $mimetype MIME type (can be obtained using the mimeinfo function)
 541  * @param bool $capitalise If true, capitalises first character of result
 542  * @return string Text description
 543  */
 544 function get_mimetype_description($mimetype,$capitalise=false) {
 545     $result=get_string($mimetype,'mimetypes');
 546     // Surrounded by square brackets indicates that there isn't a string for that
 547     // (maybe there is a better way to find this out?)
 548     if(strpos($result,'[')===0) {
 549         $result=get_string('document/unknown','mimetypes');
 550     }
 551     if($capitalise) {
 552         $result=ucfirst($result);
 553     }
 554     return $result;
 555 }
 556
 557 /**
 558  * Handles the sending of temporary file to user, download is forced.
 559  * File is deleted after abort or succesful sending.
 560  * @param string $path path to file, preferably from moodledata/temp/something; or content of file itself
 561  * @param string $filename proposed file name when saving file
 562  * @param bool $path is content of file
 563  */
 564 function send_temp_file($path, $filename, $pathisstring=false) {
 565     global $CFG;
 566
 567     // close session - not needed anymore
 568     @session_write_close();
 569
 570     if (!$pathisstring) {
 571         if (!file_exists($path)) {
 572             header('HTTP/1.0 404 not found');
 573             error(get_string('filenotfound', 'error'), $CFG->wwwroot.'/');
 574         }
 575         // executed after normal finish or abort
 576         @register_shutdown_function('send_temp_file_finished', $path);
 577     }
 578
 579     //IE compatibiltiy HACK!
 580     if (ini_get('zlib.output_compression')) {
 581         ini_set('zlib.output_compression', 'Off');
 582     }
 583
 584     // if user is using IE, urlencode the filename so that multibyte file name will show up correctly on popup
 585     if (check_browser_version('MSIE')) {
 586         $filename = urlencode($filename);
 587     }
 588
 589     $filesize = $pathisstring ? strlen($path) : filesize($path);
 590
 591     @header('Content-Disposition: attachment; filename='.$filename);
 592     @header('Content-Length: '.$filesize);
 593     if (strpos($CFG->wwwroot, 'https://') === 0) { //https sites - watch out for IE! KB812935 and KB316431
 594         @header('Cache-Control: max-age=10');
 595         @header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
 596         @header('Pragma: ');
 597     } else { //normal http - prevent caching at all cost
 598         @header('Cache-Control: private, must-revalidate, pre-check=0, post-check=0, max-age=0');
 599         @header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
 600         @header('Pragma: no-cache');
 601     }
 602     @header('Accept-Ranges: none'); // Do not allow byteserving
 603
 604     while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 605     if ($pathisstring) {
 606         echo $path;
 607     } else {
 608         readfile_chunked($path);
 609     }
 610
 611     die; //no more chars to output
 612 }
 613
 614 /**
 615  * Internal callnack function used by send_temp_file()
 616  */
 617 function send_temp_file_finished($path) {
 618     if (file_exists($path)) {
 619         @unlink($path);
 620     }
 621 }
 622
 623 /**
 624  * Handles the sending of file data to the user's browser, including support for
 625  * byteranges etc.
 626  * @param string $path Path of file on disk (including real filename), or actual content of file as string
 627  * @param string $filename Filename to send
 628  * @param int $lifetime Number of seconds before the file should expire from caches (default 24 hours)
 629  * @param int $filter 0 (default)=no filtering, 1=all files, 2=html files only
 630  * @param bool $pathisstring If true (default false), $path is the content to send and not the pathname
 631  * @param bool $forcedownload If true (default false), forces download of file rather than view in browser/plugin
 632  * @param string $mimetype Include to specify the MIME type; leave blank to have it guess the type from $filename
 633  */
 634 function send_file($path, $filename, $lifetime = 'default' , $filter=0, $pathisstring=false, $forcedownload=false, $mimetype='') {
 635     global $CFG, $COURSE;
 636
 637     // MDL-11789, apply $CFG->filelifetime here
 638     if ($lifetime === 'default') {
 639         if (!empty($CFG->filelifetime)) {
 640             $filetime = $CFG->filelifetime;
 641         } else {
 642             $filetime = 86400;
 643         }
 644     }
 645
 646     // Use given MIME type if specified, otherwise guess it using mimeinfo.
 647     // IE, Konqueror and Opera open html file directly in browser from web even when directed to save it to disk :-O
 648     // only Firefox saves all files locally before opening when content-disposition: attachment stated
 649     $isFF         = check_browser_version('Firefox', '1.5'); // only FF > 1.5 properly tested
 650     $mimetype     = ($forcedownload and !$isFF) ? 'application/x-forcedownload' :
 651                          ($mimetype ? $mimetype : mimeinfo('type', $filename));
 652     $lastmodified = $pathisstring ? time() : filemtime($path);
 653     $filesize     = $pathisstring ? strlen($path) : filesize($path);
 654
 655 /* - MDL-13949
 656     //Adobe Acrobat Reader XSS prevention
 657     if ($mimetype=='application/pdf' or mimeinfo('type', $filename)=='application/pdf') {
 658         //please note that it prevents opening of pdfs in browser when http referer disabled
 659         //or file linked from another site; browser caching of pdfs is now disabled too
 660         if (!empty($_SERVER['HTTP_RANGE'])) {
 661             //already byteserving
 662             $lifetime = 1; // >0 needed for byteserving
 663         } else if (empty($_SERVER['HTTP_REFERER']) or strpos($_SERVER['HTTP_REFERER'], $CFG->wwwroot)!==0) {
 664             $mimetype = 'application/x-forcedownload';
 665             $forcedownload = true;
 666             $lifetime = 0;
 667         } else {
 668             $lifetime = 1; // >0 needed for byteserving
 669         }
 670     }
 671 */
 672
 673     //IE compatibiltiy HACK!
 674     if (ini_get('zlib.output_compression')) {
 675         ini_set('zlib.output_compression', 'Off');
 676     }
 677
 678     //try to disable automatic sid rewrite in cookieless mode
 679     @ini_set("session.use_trans_sid", "false");
 680
 681     //do not put '@' before the next header to detect incorrect moodle configurations,
 682     //error should be better than "weird" empty lines for admins/users
 683     //TODO: should we remove all those @ before the header()? Are all of the values supported on all servers?
 684     header('Last-Modified: '. gmdate('D, d M Y H:i:s', $lastmodified) .' GMT');
 685
 686     // if user is using IE, urlencode the filename so that multibyte file name will show up correctly on popup
 687     if (check_browser_version('MSIE')) {
 688         $filename = rawurlencode($filename);
 689     }
 690
 691     if ($forcedownload) {
 692         @header('Content-Disposition: attachment; filename="'.$filename.'"');
 693     } else {
 694         @header('Content-Disposition: inline; filename="'.$filename.'"');
 695     }
 696
 697     if ($lifetime > 0) {
 698         @header('Cache-Control: max-age='.$lifetime);
 699         @header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
 700         @header('Pragma: ');
 701
 702         if (empty($CFG->disablebyteserving) && !$pathisstring && $mimetype != 'text/plain' && $mimetype != 'text/html') {
 703
 704             @header('Accept-Ranges: bytes');
 705
 706             if (!empty($_SERVER['HTTP_RANGE']) && strpos($_SERVER['HTTP_RANGE'],'bytes=') !== FALSE) {
 707                 // byteserving stuff - for acrobat reader and download accelerators
 708                 // see: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35
 709                 // inspired by: http://www.coneural.org/florian/papers/04_byteserving.php
 710                 $ranges = false;
 711                 if (preg_match_all('/(\d*)-(\d*)/', $_SERVER['HTTP_RANGE'], $ranges, PREG_SET_ORDER)) {
 712                     foreach ($ranges as $key=>$value) {
 713                         if ($ranges[$key][1] == '') {
 714                             //suffix case
 715                             $ranges[$key][1] = $filesize - $ranges[$key][2];
 716                             $ranges[$key][2] = $filesize - 1;
 717                         } else if ($ranges[$key][2] == '' || $ranges[$key][2] > $filesize - 1) {
 718                             //fix range length
 719                             $ranges[$key][2] = $filesize - 1;
 720                         }
 721                         if ($ranges[$key][2] != '' && $ranges[$key][2] < $ranges[$key][1]) {
 722                             //invalid byte-range ==> ignore header
 723                             $ranges = false;
 724                             break;
 725                         }
 726                         //prepare multipart header
 727                         $ranges[$key][0] =  "\r\n--".BYTESERVING_BOUNDARY."\r\nContent-Type: $mimetype\r\n";
 728                         $ranges[$key][0] .= "Content-Range: bytes {$ranges[$key][1]}-{$ranges[$key][2]}/$filesize\r\n\r\n";
 729                     }
 730                 } else {
 731                     $ranges = false;
 732                 }
 733                 if ($ranges) {
 734                     byteserving_send_file($path, $mimetype, $ranges);
 735                 }
 736             }
 737         } else {
 738             /// Do not byteserve (disabled, strings, text and html files).
 739             @header('Accept-Ranges: none');
 740         }
 741     } else { // Do not cache files in proxies and browsers
 742         if (strpos($CFG->wwwroot, 'https://') === 0) { //https sites - watch out for IE! KB812935 and KB316431
 743             @header('Cache-Control: max-age=10');
 744             @header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
 745             @header('Pragma: ');
 746         } else { //normal http - prevent caching at all cost
 747             @header('Cache-Control: private, must-revalidate, pre-check=0, post-check=0, max-age=0');
 748             @header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
 749             @header('Pragma: no-cache');
 750         }
 751         @header('Accept-Ranges: none'); // Do not allow byteserving when caching disabled
 752     }
 753
 754     if (empty($filter)) {
 755         if ($mimetype == 'text/html' && !empty($CFG->usesid) && empty($_COOKIE['MoodleSession'.$CFG->sessioncookie])) {
 756             //cookieless mode - rewrite links
 757             @header('Content-Type: text/html');
 758             $path = $pathisstring ? $path : implode('', file($path));
 759             $path = sid_ob_rewrite($path);
 760             $filesize = strlen($path);
 761             $pathisstring = true;
 762         } else if ($mimetype == 'text/plain') {
 763             @header('Content-Type: Text/plain; charset=utf-8'); //add encoding
 764         } else {
 765             @header('Content-Type: '.$mimetype);
 766         }
 767         @header('Content-Length: '.$filesize);
 768         while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 769         if ($pathisstring) {
 770             echo $path;
 771         } else {
 772             readfile_chunked($path);
 773         }
 774     } else {     // Try to put the file through filters
 775         if ($mimetype == 'text/html') {
 776             $options = new object();
 777             $options->noclean = true;
 778             $options->nocache = true; // temporary workaround for MDL-5136
 779             $text = $pathisstring ? $path : implode('', file($path));
 780
 781             $text = file_modify_html_header($text);
 782             $output = format_text($text, FORMAT_HTML, $options, $COURSE->id);
 783             if (!empty($CFG->usesid) && empty($_COOKIE['MoodleSession'.$CFG->sessioncookie])) {
 784                 //cookieless mode - rewrite links
 785                 $output = sid_ob_rewrite($output);
 786             }
 787
 788             @header('Content-Length: '.strlen($output));
 789             @header('Content-Type: text/html');
 790             while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 791             echo $output;
 792         // only filter text if filter all files is selected
 793         } else if (($mimetype == 'text/plain') and ($filter == 1)) {
 794             $options = new object();
 795             $options->newlines = false;
 796             $options->noclean = true;
 797             $text = htmlentities($pathisstring ? $path : implode('', file($path)));
 798             $output = '<pre>'. format_text($text, FORMAT_MOODLE, $options, $COURSE->id) .'</pre>';
 799             if (!empty($CFG->usesid) && empty($_COOKIE['MoodleSession'.$CFG->sessioncookie])) {
 800                 //cookieless mode - rewrite links
 801                 $output = sid_ob_rewrite($output);
 802             }
 803
 804             @header('Content-Length: '.strlen($output));
 805             @header('Content-Type: text/html; charset=utf-8'); //add encoding
 806             while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 807             echo $output;
 808         } else {    // Just send it out raw
 809             @header('Content-Length: '.$filesize);
 810             @header('Content-Type: '.$mimetype);
 811             while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 812             if ($pathisstring) {
 813                 echo $path;
 814             }else {
 815                 readfile_chunked($path);
 816             }
 817         }
 818     }
 819     die; //no more chars to output!!!
 820 }
 821
 822 function get_records_csv($file, $table) {
 823     global $CFG, $db;
 824
 825     if (!$metacolumns = $db->MetaColumns($CFG->prefix . $table)) {
 826         return false;
 827     }
 828
 829     if(!($handle = @fopen($file, 'r'))) {
 830         error('get_records_csv failed to open '.$file);
 831     }
 832
 833     $fieldnames = fgetcsv($handle, 4096);
 834     if(empty($fieldnames)) {
 835         fclose($handle);
 836         return false;
 837     }
 838
 839     $columns = array();
 840
 841     foreach($metacolumns as $metacolumn) {
 842         $ord = array_search($metacolumn->name, $fieldnames);
 843         if(is_int($ord)) {
 844             $columns[$metacolumn->name] = $ord;
 845         }
 846     }
 847
 848     $rows = array();
 849
 850     while (($data = fgetcsv($handle, 4096)) !== false) {
 851         $item = new stdClass;
 852         foreach($columns as $name => $ord) {
 853             $item->$name = $data[$ord];
 854         }
 855         $rows[] = $item;
 856     }
 857
 858     fclose($handle);
 859     return $rows;
 860 }
 861
 862 function put_records_csv($file, $records, $table = NULL) {
 863     global $CFG, $db;
 864
 865     if (empty($records)) {
 866         return true;
 867     }
 868
 869     $metacolumns = NULL;
 870     if ($table !== NULL && !$metacolumns = $db->MetaColumns($CFG->prefix . $table)) {
 871         return false;
 872     }
 873
 874     echo "x";
 875
 876     if(!($fp = @fopen($CFG->dataroot.'/temp/'.$file, 'w'))) {
 877         error('put_records_csv failed to open '.$file);
 878     }
 879
 880     $proto = reset($records);
 881     if(is_object($proto)) {
 882         $fields_records = array_keys(get_object_vars($proto));
 883     }
 884     else if(is_array($proto)) {
 885         $fields_records = array_keys($proto);
 886     }
 887     else {
 888         return false;
 889     }
 890     echo "x";
 891
 892     if(!empty($metacolumns)) {
 893         $fields_table = array_map(create_function('$a', 'return $a->name;'), $metacolumns);
 894         $fields = array_intersect($fields_records, $fields_table);
 895     }
 896     else {
 897         $fields = $fields_records;
 898     }
 899
 900     fwrite($fp, implode(',', $fields));
 901     fwrite($fp, "\r\n");
 902
 903     foreach($records as $record) {
 904         $array  = (array)$record;
 905         $values = array();
 906         foreach($fields as $field) {
 907             if(strpos($array[$field], ',')) {
 908                 $values[] = '"'.str_replace('"', '\"', $array[$field]).'"';
 909             }
 910             else {
 911                 $values[] = $array[$field];
 912             }
 913         }
 914         fwrite($fp, implode(',', $values)."\r\n");
 915     }
 916
 917     fclose($fp);
 918     return true;
 919 }
 920
 921
 922 /**
 923  * Recursively delete the file or folder with path $location. That is,
 924  * if it is a file delete it. If it is a folder, delete all its content
 925  * then delete it. If $location does not exist to start, that is not
 926  * considered an error.
 927  *
 928  * @param $location the path to remove.
 929  */
 930 function fulldelete($location) {
 931     if (is_dir($location)) {
 932         $currdir = opendir($location);
 933         while (false !== ($file = readdir($currdir))) {
 934             if ($file <> ".." && $file <> ".") {
 935                 $fullfile = $location."/".$file;
 936                 if (is_dir($fullfile)) {
 937                     if (!fulldelete($fullfile)) {
 938                         return false;
 939                     }
 940                 } else {
 941                     if (!unlink($fullfile)) {
 942                         return false;
 943                     }
 944                 }
 945             }
 946         }
 947         closedir($currdir);
 948         if (! rmdir($location)) {
 949             return false;
 950         }
 951
 952     } else if (file_exists($location)) {
 953         if (!unlink($location)) {
 954             return false;
 955         }
 956     }
 957     return true;
 958 }
 959
 960 /**
 961  * Improves memory consumptions and works around buggy readfile() in PHP 5.0.4 (2MB readfile limit).
 962  */
 963 function readfile_chunked($filename, $retbytes=true) {
 964     $chunksize = 1*(1024*1024); // 1MB chunks - must be less than 2MB!
 965     $buffer = '';
 966     $cnt =0;
 967     $handle = fopen($filename, 'rb');
 968     if ($handle === false) {
 969         return false;
 970     }
 971
 972     while (!feof($handle)) {
 973         @set_time_limit(60*60); //reset time limit to 60 min - should be enough for 1 MB chunk
 974         $buffer = fread($handle, $chunksize);
 975         echo $buffer;
 976         flush();
 977         if ($retbytes) {
 978             $cnt += strlen($buffer);
 979         }
 980     }
 981     $status = fclose($handle);
 982     if ($retbytes && $status) {
 983         return $cnt; // return num. bytes delivered like readfile() does.
 984     }
 985     return $status;
 986 }
 987
 988 /**
 989  * Send requested byterange of file.
 990  */
 991 function byteserving_send_file($filename, $mimetype, $ranges) {
 992     $chunksize = 1*(1024*1024); // 1MB chunks - must be less than 2MB!
 993     $handle = fopen($filename, 'rb');
 994     if ($handle === false) {
 995         die;
 996     }
 997     if (count($ranges) == 1) { //only one range requested
 998         $length = $ranges[0][2] - $ranges[0][1] + 1;
 999         @header('HTTP/1.1 206 Partial content');
1000         @header('Content-Length: '.$length);
1001         @header('Content-Range: bytes '.$ranges[0][1].'-'.$ranges[0][2].'/'.filesize($filename));
1002         @header('Content-Type: '.$mimetype);
1003         while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
1004         $buffer = '';
1005         fseek($handle, $ranges[0][1]);
1006         while (!feof($handle) && $length > 0) {
1007             @set_time_limit(60*60); //reset time limit to 60 min - should be enough for 1 MB chunk
1008             $buffer = fread($handle, ($chunksize < $length ? $chunksize : $length));
1009             echo $buffer;
1010             flush();
1011             $length -= strlen($buffer);
1012         }
1013         fclose($handle);
1014         die;
1015     } else { // multiple ranges requested - not tested much
1016         $totallength = 0;
1017         foreach($ranges as $range) {
1018             $totallength += strlen($range[0]) + $range[2] - $range[1] + 1;
1019         }
1020         $totallength += strlen("\r\n--".BYTESERVING_BOUNDARY."--\r\n");
1021         @header('HTTP/1.1 206 Partial content');
1022         @header('Content-Length: '.$totallength);
1023         @header('Content-Type: multipart/byteranges; boundary='.BYTESERVING_BOUNDARY);
1024         //TODO: check if "multipart/x-byteranges" is more compatible with current readers/browsers/servers
1025         while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
1026         foreach($ranges as $range) {
1027             $length = $range[2] - $range[1] + 1;
1028             echo $range[0];
1029             $buffer = '';
1030             fseek($handle, $range[1]);
1031             while (!feof($handle) && $length > 0) {
1032                 @set_time_limit(60*60); //reset time limit to 60 min - should be enough for 1 MB chunk
1033                 $buffer = fread($handle, ($chunksize < $length ? $chunksize : $length));
1034                 echo $buffer;
1035                 flush();
1036                 $length -= strlen($buffer);
1037             }
1038         }
1039         echo "\r\n--".BYTESERVING_BOUNDARY."--\r\n";
1040         fclose($handle);
1041         die;
1042     }
1043 }
1044
1045 /**
1046  * add includes (js and css) into uploaded files
1047  * before returning them, useful for themes and utf.js includes
1048  * @param string text - text to search and replace
1049  * @return string - text with added head includes
1050  */
1051 function file_modify_html_header($text) {
1052     // first look for <head> tag
1053     global $CFG;
1054
1055     $stylesheetshtml = '';
1056     foreach ($CFG->stylesheets as $stylesheet) {
1057         $stylesheetshtml .= '<link rel="stylesheet" type="text/css" href="'.$stylesheet.'" />'."\n";
1058     }
1059
1060     $filters = explode(",", $CFG->textfilters);
1061     if (in_array('filter/mediaplugin', $filters)) {
1062         // this script is needed by most media filter plugins.
1063         $ufo = "\n".'<script type="text/javascript" src="'.$CFG->wwwroot.'/lib/ufo.js"></script>'."\n";
1064     } else {
1065         $ufo = '';
1066     }
1067
1068     preg_match('/\<head\>|\<HEAD\>/', $text, $matches);
1069     if ($matches) {
1070         $replacement = '<head>'.$ufo.$stylesheetshtml;
1071         $text = preg_replace('/\<head\>|\<HEAD\>/', $replacement, $text, 1);
1072         return $text;
1073     }
1074
1075     // if not, look for <html> tag, and stick <head> right after
1076     preg_match('/\<html\>|\<HTML\>/', $text, $matches);
1077     if ($matches) {
1078         // replace <html> tag with <html><head>includes</head>
1079         $replacement = '<html>'."\n".'<head>'.$ufo.$stylesheetshtml.'</head>';
1080         $text = preg_replace('/\<html\>|\<HTML\>/', $replacement, $text, 1);
1081         return $text;
1082     }
1083
1084     // if not, look for <body> tag, and stick <head> before body
1085     preg_match('/\<body\>|\<BODY\>/', $text, $matches);
1086     if ($matches) {
1087         $replacement = '<head>'.$ufo.$stylesheetshtml.'</head>'."\n".'<body>';
1088         $text = preg_replace('/\<body\>|\<BODY\>/', $replacement, $text, 1);
1089         return $text;
1090     }
1091
1092     // if not, just stick a <head> tag at the beginning
1093     $text = '<head>'.$ufo.$stylesheetshtml.'</head>'."\n".$text;
1094     return $text;
1095 }
1096
1097 ?>