lib/filelib.php

   1 <?php //$Id$
   2
   3 require_once($CFG->libdir.'/libcurlemu/libcurlemu.inc.php'); // might be moved to setup.php later
   4
   5 define('BYTESERVING_BOUNDARY', 's1k2o3d4a5k6s7'); //unique string constant
   6
   7 /**
   8  * Fetches content of file from Internet (using proxy if defined).
   9  *
  10  * @return mixed false if request failed or content of the file as string if ok.
  11  */
  12 function download_file_content($url) {
  13     $ch = curl_init($url);
  14     curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
  15     curl_setopt($ch, CURLOPT_HEADER, false);
  16     if (!empty($CFG->proxyhost)) {
  17         curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, true);
  18         if (empty($CFG->proxyport)) {
  19             curl_setopt($ch, CURLOPT_PROXY, $CFG->proxy);
  20         } else {
  21             curl_setopt($ch, CURLOPT_PROXY, $CFG->proxy.':'.$CFG->proxyport);
  22         }
  23         if(!empty($CFG->proxyuser) and !empty($CFG->proxypassword)) {
  24             curl_setopt($ch, CURLOPT_PROXYUSERPWD, $CFG->proxyuser.':'.$CFG->proxypassword);
  25         }
  26     }
  27     $result = curl_exec($ch);
  28     curl_close($ch);
  29     return $result;
  30 }
  31
  32 /**
  33  * @return List of information about file types based on extensions.
  34  *   Associative array of extension (lower-case) to associative array
  35  *   from 'element name' to data. Current element names are 'type' and 'icon'.
  36  *   Unknown types should use the 'xxx' entry which includes defaults.
  37  */
  38 function get_mimetypes_array() {
  39     return array (
  40         'xxx'  => array ('type'=>'document/unknown', 'icon'=>'unknown.gif'),
  41         '3gp'  => array ('type'=>'video/quicktime', 'icon'=>'video.gif'),
  42         'ai'   => array ('type'=>'application/postscript', 'icon'=>'image.gif'),
  43         'aif'  => array ('type'=>'audio/x-aiff', 'icon'=>'audio.gif'),
  44         'aiff' => array ('type'=>'audio/x-aiff', 'icon'=>'audio.gif'),
  45         'aifc' => array ('type'=>'audio/x-aiff', 'icon'=>'audio.gif'),
  46         'applescript'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  47         'asc'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  48         'asm'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  49         'au'   => array ('type'=>'audio/au', 'icon'=>'audio.gif'),
  50         'avi'  => array ('type'=>'video/x-ms-wm', 'icon'=>'avi.gif'),
  51         'bmp'  => array ('type'=>'image/bmp', 'icon'=>'image.gif'),
  52         'c'    => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  53         'cct'  => array ('type'=>'shockwave/director', 'icon'=>'flash.gif'),
  54         'cpp'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  55         'cs'   => array ('type'=>'application/x-csh', 'icon'=>'text.gif'),
  56         'css'  => array ('type'=>'text/css', 'icon'=>'text.gif'),
  57         'csv'  => array ('type'=>'text/csv', 'icon'=>'excel.gif'),
  58         'dv'   => array ('type'=>'video/x-dv', 'icon'=>'video.gif'),
  59         'dmg'  => array ('type'=>'application/octet-stream', 'icon'=>'dmg.gif'),
  60         'doc'  => array ('type'=>'application/msword', 'icon'=>'word.gif'),
  61         'docx' => array ('type'=>'application/msword', 'icon'=>'docx.gif'),
  62         'docm' => array ('type'=>'application/msword', 'icon'=>'docm.gif'),
  63         'dotx' => array ('type'=>'application/msword', 'icon'=>'dotx.gif'),
  64         'dcr'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
  65         'dif'  => array ('type'=>'video/x-dv', 'icon'=>'video.gif'),
  66         'dir'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
  67         'dxr'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
  68         'eps'  => array ('type'=>'application/postscript', 'icon'=>'pdf.gif'),
  69         'fdf'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
  70         'flv'  => array ('type'=>'video/x-flv', 'icon'=>'video.gif'),
  71         'gif'  => array ('type'=>'image/gif', 'icon'=>'image.gif'),
  72         'gtar' => array ('type'=>'application/x-gtar', 'icon'=>'zip.gif'),
  73         'tgz'  => array ('type'=>'application/g-zip', 'icon'=>'zip.gif'),
  74         'gz'   => array ('type'=>'application/g-zip', 'icon'=>'zip.gif'),
  75         'gzip' => array ('type'=>'application/g-zip', 'icon'=>'zip.gif'),
  76         'h'    => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  77         'hpp'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  78         'hqx'  => array ('type'=>'application/mac-binhex40', 'icon'=>'zip.gif'),
  79         'htc'  => array ('type'=>'text/x-component', 'icon'=>'text.gif'),
  80         'html' => array ('type'=>'text/html', 'icon'=>'html.gif'),
  81         'xhtml'=> array ('type'=>'application/xhtml+xml', 'icon'=>'html.gif'),
  82         'htm'  => array ('type'=>'text/html', 'icon'=>'html.gif'),
  83         'ico'  => array ('type'=>'image/vnd.microsoft.icon', 'icon'=>'image.gif'),
  84         'isf'  => array ('type'=>'application/inspiration', 'icon'=>'isf.gif'),
  85         'ist'  => array ('type'=>'application/inspiration.template', 'icon'=>'isf.gif'),
  86         'java' => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  87         'jcb'  => array ('type'=>'text/xml', 'icon'=>'jcb.gif'),
  88         'jcl'  => array ('type'=>'text/xml', 'icon'=>'jcl.gif'),
  89         'jcw'  => array ('type'=>'text/xml', 'icon'=>'jcw.gif'),
  90         'jmt'  => array ('type'=>'text/xml', 'icon'=>'jmt.gif'),
  91         'jmx'  => array ('type'=>'text/xml', 'icon'=>'jmx.gif'),
  92         'jpe'  => array ('type'=>'image/jpeg', 'icon'=>'image.gif'),
  93         'jpeg' => array ('type'=>'image/jpeg', 'icon'=>'image.gif'),
  94         'jpg'  => array ('type'=>'image/jpeg', 'icon'=>'image.gif'),
  95         'jqz'  => array ('type'=>'text/xml', 'icon'=>'jqz.gif'),
  96         'js'   => array ('type'=>'application/x-javascript', 'icon'=>'text.gif'),
  97         'latex'=> array ('type'=>'application/x-latex', 'icon'=>'text.gif'),
  98         'm'    => array ('type'=>'text/plain', 'icon'=>'text.gif'),
  99         'mov'  => array ('type'=>'video/quicktime', 'icon'=>'video.gif'),
 100         'movie'=> array ('type'=>'video/x-sgi-movie', 'icon'=>'video.gif'),
 101         'm3u'  => array ('type'=>'audio/x-mpegurl', 'icon'=>'audio.gif'),
 102         'mp3'  => array ('type'=>'audio/mp3', 'icon'=>'audio.gif'),
 103         'mp4'  => array ('type'=>'video/mp4', 'icon'=>'video.gif'),
 104         'mpeg' => array ('type'=>'video/mpeg', 'icon'=>'video.gif'),
 105         'mpe'  => array ('type'=>'video/mpeg', 'icon'=>'video.gif'),
 106         'mpg'  => array ('type'=>'video/mpeg', 'icon'=>'video.gif'),
 107
 108         'odt'  => array ('type'=>'application/vnd.oasis.opendocument.text', 'icon'=>'odt.gif'),
 109         'ott'  => array ('type'=>'application/vnd.oasis.opendocument.text-template', 'icon'=>'odt.gif'),
 110         'oth'  => array ('type'=>'application/vnd.oasis.opendocument.text-web', 'icon'=>'odt.gif'),
 111         'odm'  => array ('type'=>'application/vnd.oasis.opendocument.text-master', 'icon'=>'odm.gif'),
 112         'odg'  => array ('type'=>'application/vnd.oasis.opendocument.graphics', 'icon'=>'odg.gif'),
 113         'otg'  => array ('type'=>'application/vnd.oasis.opendocument.graphics-template', 'icon'=>'odg.gif'),
 114         'odp'  => array ('type'=>'application/vnd.oasis.opendocument.presentation', 'icon'=>'odp.gif'),
 115         'otp'  => array ('type'=>'application/vnd.oasis.opendocument.presentation-template', 'icon'=>'odp.gif'),
 116         'ods'  => array ('type'=>'application/vnd.oasis.opendocument.spreadsheet', 'icon'=>'ods.gif'),
 117         'ots'  => array ('type'=>'application/vnd.oasis.opendocument.spreadsheet-template', 'icon'=>'ods.gif'),
 118         'odc'  => array ('type'=>'application/vnd.oasis.opendocument.chart', 'icon'=>'odc.gif'),
 119         'odf'  => array ('type'=>'application/vnd.oasis.opendocument.formula', 'icon'=>'odf.gif'),
 120         'odb'  => array ('type'=>'application/vnd.oasis.opendocument.database', 'icon'=>'odb.gif'),
 121         'odi'  => array ('type'=>'application/vnd.oasis.opendocument.image', 'icon'=>'odi.gif'),
 122
 123         'pct'  => array ('type'=>'image/pict', 'icon'=>'image.gif'),
 124         'pdf'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 125         'php'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 126         'pic'  => array ('type'=>'image/pict', 'icon'=>'image.gif'),
 127         'pict' => array ('type'=>'image/pict', 'icon'=>'image.gif'),
 128         'png'  => array ('type'=>'image/png', 'icon'=>'image.gif'),
 129         'pps'  => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'powerpoint.gif'),
 130         'ppt'  => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'powerpoint.gif'),
 131         'pptx' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'pptx.gif'),
 132         'pptm' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'pptm.gif'),
 133         'potx' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'potx.gif'),
 134         'potm' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'potm.gif'),
 135         'ppam' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'ppam.gif'),
 136         'ppsx' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'ppsx.gif'),
 137         'ppsm' => array ('type'=>'application/vnd.ms-powerpoint', 'icon'=>'ppsm.gif'),
 138         'ps'   => array ('type'=>'application/postscript', 'icon'=>'pdf.gif'),
 139         'qt'   => array ('type'=>'video/quicktime', 'icon'=>'video.gif'),
 140         'ra'   => array ('type'=>'audio/x-realaudio', 'icon'=>'audio.gif'),
 141         'ram'  => array ('type'=>'audio/x-pn-realaudio', 'icon'=>'audio.gif'),
 142         'rhb'  => array ('type'=>'text/xml', 'icon'=>'xml.gif'),
 143         'rm'   => array ('type'=>'audio/x-pn-realaudio', 'icon'=>'audio.gif'),
 144         'rtf'  => array ('type'=>'text/rtf', 'icon'=>'text.gif'),
 145         'rtx'  => array ('type'=>'text/richtext', 'icon'=>'text.gif'),
 146         'sh'   => array ('type'=>'application/x-sh', 'icon'=>'text.gif'),
 147         'sit'  => array ('type'=>'application/x-stuffit', 'icon'=>'zip.gif'),
 148         'smi'  => array ('type'=>'application/smil', 'icon'=>'text.gif'),
 149         'smil' => array ('type'=>'application/smil', 'icon'=>'text.gif'),
 150         'sqt'  => array ('type'=>'text/xml', 'icon'=>'xml.gif'),
 151         'svg'  => array ('type'=>'image/svg+xml', 'icon'=>'image.gif'),
 152         'svgz' => array ('type'=>'image/svg+xml', 'icon'=>'image.gif'),
 153         'swa'  => array ('type'=>'application/x-director', 'icon'=>'flash.gif'),
 154         'swf'  => array ('type'=>'application/x-shockwave-flash', 'icon'=>'flash.gif'),
 155         'swfl' => array ('type'=>'application/x-shockwave-flash', 'icon'=>'flash.gif'),
 156
 157         'sxw'  => array ('type'=>'application/vnd.sun.xml.writer', 'icon'=>'odt.gif'),
 158         'stw'  => array ('type'=>'application/vnd.sun.xml.writer.template', 'icon'=>'odt.gif'),
 159         'sxc'  => array ('type'=>'application/vnd.sun.xml.calc', 'icon'=>'odt.gif'),
 160         'stc'  => array ('type'=>'application/vnd.sun.xml.calc.template', 'icon'=>'odt.gif'),
 161         'sxd'  => array ('type'=>'application/vnd.sun.xml.draw', 'icon'=>'odt.gif'),
 162         'std'  => array ('type'=>'application/vnd.sun.xml.draw.template', 'icon'=>'odt.gif'),
 163         'sxi'  => array ('type'=>'application/vnd.sun.xml.impress', 'icon'=>'odt.gif'),
 164         'sti'  => array ('type'=>'application/vnd.sun.xml.impress.template', 'icon'=>'odt.gif'),
 165         'sxg'  => array ('type'=>'application/vnd.sun.xml.writer.global', 'icon'=>'odt.gif'),
 166         'sxm'  => array ('type'=>'application/vnd.sun.xml.math', 'icon'=>'odt.gif'),
 167
 168         'tar'  => array ('type'=>'application/x-tar', 'icon'=>'zip.gif'),
 169         'tif'  => array ('type'=>'image/tiff', 'icon'=>'image.gif'),
 170         'tiff' => array ('type'=>'image/tiff', 'icon'=>'image.gif'),
 171         'tex'  => array ('type'=>'application/x-tex', 'icon'=>'text.gif'),
 172         'texi' => array ('type'=>'application/x-texinfo', 'icon'=>'text.gif'),
 173         'texinfo'  => array ('type'=>'application/x-texinfo', 'icon'=>'text.gif'),
 174         'tsv'  => array ('type'=>'text/tab-separated-values', 'icon'=>'text.gif'),
 175         'txt'  => array ('type'=>'text/plain', 'icon'=>'text.gif'),
 176         'wav'  => array ('type'=>'audio/wav', 'icon'=>'audio.gif'),
 177         'wmv'  => array ('type'=>'video/x-ms-wmv', 'icon'=>'avi.gif'),
 178         'asf'  => array ('type'=>'video/x-ms-asf', 'icon'=>'avi.gif'),
 179         'xdp'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 180         'xfd'  => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 181         'xfdf' => array ('type'=>'application/pdf', 'icon'=>'pdf.gif'),
 182         'xls'  => array ('type'=>'application/vnd.ms-excel', 'icon'=>'excel.gif'),
 183         'xlsx' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlsx.gif'),
 184         'xlsm' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlsm.gif'),
 185         'xltx' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xltx.gif'),
 186         'xltm' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xltm.gif'),
 187         'xlsb' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlsb.gif'),
 188         'xlam' => array ('type'=>'application/vnd.ms-excel', 'icon'=>'xlam.gif'),
 189         'xml'  => array ('type'=>'application/xml', 'icon'=>'xml.gif'),
 190         'xsl'  => array ('type'=>'text/xml', 'icon'=>'xml.gif'),
 191         'zip'  => array ('type'=>'application/zip', 'icon'=>'zip.gif')
 192     );
 193 }
 194
 195 /**
 196  * Obtains information about a filetype based on its extension. Will
 197  * use a default if no information is present about that particular
 198  * extension.
 199  * @param string $element Desired information (usually 'icon'
 200  *   for icon filename or 'type' for MIME type)
 201  * @param string $filename Filename we're looking up
 202  * @return string Requested piece of information from array
 203  */
 204 function mimeinfo($element, $filename) {
 205     static $mimeinfo;
 206     $mimeinfo=get_mimetypes_array();
 207
 208     if (eregi('\.([a-z0-9]+)$', $filename, $match)) {
 209         if (isset($mimeinfo[strtolower($match[1])][$element])) {
 210             return $mimeinfo[strtolower($match[1])][$element];
 211         } else {
 212             return $mimeinfo['xxx'][$element];   // By default
 213         }
 214     } else {
 215         return $mimeinfo['xxx'][$element];   // By default
 216     }
 217 }
 218
 219 /**
 220  * Obtains information about a filetype based on the MIME type rather than
 221  * the other way around.
 222  * @param string $element Desired information (usually 'icon')
 223  * @param string $mimetype MIME type we're looking up
 224  * @return string Requested piece of information from array
 225  */
 226 function mimeinfo_from_type($element, $mimetype) {
 227     static $mimeinfo;
 228     $mimeinfo=get_mimetypes_array();
 229
 230     foreach($mimeinfo as $values) {
 231         if($values['type']==$mimetype) {
 232             if(isset($values[$element])) {
 233                 return $values[$element];
 234             }
 235             break;
 236         }
 237     }
 238     return $mimeinfo['xxx'][$element]; // Default
 239 }
 240
 241 /**
 242  * Get information about a filetype based on the icon file.
 243  * @param string $element Desired information (usually 'icon')
 244  * @param string $icon Icon file path.
 245  * @return string Requested piece of information from array
 246  */
 247 function mimeinfo_from_icon($element, $icon) {
 248     static $mimeinfo;
 249     $mimeinfo=get_mimetypes_array();
 250
 251     if (preg_match("/\/(.*)/", $icon, $matches)) {
 252         $icon = $matches[1];
 253     }
 254     $info = $mimeinfo['xxx'][$element]; // Default
 255     foreach($mimeinfo as $values) {
 256         if($values['icon']==$icon) {
 257             if(isset($values[$element])) {
 258                 $info = $values[$element];
 259             }
 260             //No break, for example for 'excel.gif' we don't want 'csv'!
 261         }
 262     }
 263     return $info;
 264 }
 265
 266 /**
 267  * Obtains descriptions for file types (e.g. 'Microsoft Word document') from the
 268  * mimetypes.php language file.
 269  * @param string $mimetype MIME type (can be obtained using the mimeinfo function)
 270  * @param bool $capitalise If true, capitalises first character of result
 271  * @return string Text description
 272  */
 273 function get_mimetype_description($mimetype,$capitalise=false) {
 274     $result=get_string($mimetype,'mimetypes');
 275     // Surrounded by square brackets indicates that there isn't a string for that
 276     // (maybe there is a better way to find this out?)
 277     if(strpos($result,'[')===0) {
 278         $result=get_string('document/unknown','mimetypes');
 279     }
 280     if($capitalise) {
 281         $result=ucfirst($result);
 282     }
 283     return $result;
 284 }
 285
 286 /**
 287  * Handles the sending of file data to the user's browser, including support for
 288  * byteranges etc.
 289  * @param string $path Path of file on disk (including real filename), or actual content of file as string
 290  * @param string $filename Filename to send
 291  * @param int $lifetime Number of seconds before the file should expire from caches (default 24 hours)
 292  * @param int $filter 0 (default)=no filtering, 1=all files, 2=html files only
 293  * @param bool $pathisstring If true (default false), $path is the content to send and not the pathname
 294  * @param bool $forcedownload If true (default false), forces download of file rather than view in browser/plugin
 295  * @param string $mimetype Include to specify the MIME type; leave blank to have it guess the type from $filename
 296  */
 297 function send_file($path, $filename, $lifetime=86400 , $filter=0, $pathisstring=false, $forcedownload=false, $mimetype='') {
 298     global $CFG, $COURSE;
 299
 300     // Use given MIME type if specified, otherwise guess it using mimeinfo.
 301     // IE, Konqueror and Opera open html file directly in browser from web even when directed to save it to disk :-O
 302     // only Firefox saves all files locally before opening when content-disposition: attachment stated
 303     $isFF         = check_browser_version('Firefox', '1.5'); // only FF > 1.5 properly tested
 304     $mimetype     = ($forcedownload and !$isFF) ? 'application/x-forcedownload' :
 305                          ($mimetype ? $mimetype : mimeinfo('type', $filename));
 306     $lastmodified = $pathisstring ? time() : filemtime($path);
 307     $filesize     = $pathisstring ? strlen($path) : filesize($path);
 308
 309     //Adobe Acrobat Reader XSS prevention
 310     if ($mimetype=='application/pdf' or mimeinfo('type', $filename)=='application/pdf') {
 311         //please note that it prevents opening of pdfs in browser when http referer disabled
 312         //or file linked from another site; browser caching of pdfs is now disabled too
 313         if (!empty($_SERVER['HTTP_RANGE'])) {
 314             //already byteserving
 315             $lifetime = 1; // >0 needed for byteserving
 316         } else if (empty($_SERVER['HTTP_REFERER']) or strpos($_SERVER['HTTP_REFERER'], $CFG->wwwroot)!==0) {
 317             $mimetype = 'application/x-forcedownload';
 318             $forcedownload = true;
 319             $lifetime = 0;
 320         } else {
 321             $lifetime = 1; // >0 needed for byteserving
 322         }
 323     }
 324
 325     //IE compatibiltiy HACK!
 326     if (ini_get('zlib.output_compression')) {
 327         ini_set('zlib.output_compression', 'Off');
 328     }
 329
 330     //try to disable automatic sid rewrite in cookieless mode
 331     @ini_set("session.use_trans_sid", "false");
 332
 333     //do not put '@' before the next header to detect incorrect moodle configurations,
 334     //error should be better than "weird" empty lines for admins/users
 335     //TODO: should we remove all those @ before the header()? Are all of the values supported on all servers?
 336     header('Last-Modified: '. gmdate('D, d M Y H:i:s', $lastmodified) .' GMT');
 337
 338     if ($forcedownload) {
 339         @header('Content-Disposition: attachment; filename='.$filename);
 340     } else {
 341         @header('Content-Disposition: inline; filename='.$filename);
 342     }
 343
 344     if ($lifetime > 0) {
 345         @header('Cache-Control: max-age='.$lifetime);
 346         @header('Expires: '. gmdate('D, d M Y H:i:s', time() + $lifetime) .' GMT');
 347         @header('Pragma: ');
 348
 349         if (empty($CFG->disablebyteserving) && !$pathisstring && $mimetype != 'text/plain' && $mimetype != 'text/html') {
 350
 351             @header('Accept-Ranges: bytes');
 352
 353             if (!empty($_SERVER['HTTP_RANGE']) && strpos($_SERVER['HTTP_RANGE'],'bytes=') !== FALSE) {
 354                 // byteserving stuff - for acrobat reader and download accelerators
 355                 // see: http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.35
 356                 // inspired by: http://www.coneural.org/florian/papers/04_byteserving.php
 357                 $ranges = false;
 358                 if (preg_match_all('/(\d*)-(\d*)/', $_SERVER['HTTP_RANGE'], $ranges, PREG_SET_ORDER)) {
 359                     foreach ($ranges as $key=>$value) {
 360                         if ($ranges[$key][1] == '') {
 361                             //suffix case
 362                             $ranges[$key][1] = $filesize - $ranges[$key][2];
 363                             $ranges[$key][2] = $filesize - 1;
 364                         } else if ($ranges[$key][2] == '' || $ranges[$key][2] > $filesize - 1) {
 365                             //fix range length
 366                             $ranges[$key][2] = $filesize - 1;
 367                         }
 368                         if ($ranges[$key][2] != '' && $ranges[$key][2] < $ranges[$key][1]) {
 369                             //invalid byte-range ==> ignore header
 370                             $ranges = false;
 371                             break;
 372                         }
 373                         //prepare multipart header
 374                         $ranges[$key][0] =  "\r\n--".BYTESERVING_BOUNDARY."\r\nContent-Type: $mimetype\r\n";
 375                         $ranges[$key][0] .= "Content-Range: bytes {$ranges[$key][1]}-{$ranges[$key][2]}/$filesize\r\n\r\n";
 376                     }
 377                 } else {
 378                     $ranges = false;
 379                 }
 380                 if ($ranges) {
 381                     byteserving_send_file($path, $mimetype, $ranges);
 382                 }
 383             }
 384         } else {
 385             /// Do not byteserve (disabled, strings, text and html files).
 386             @header('Accept-Ranges: none');
 387         }
 388     } else { // Do not cache files in proxies and browsers
 389         if (strpos($CFG->wwwroot, 'https://') === 0) { //https sites - watch out for IE! KB812935 and KB316431
 390             @header('Cache-Control: max-age=10');
 391             @header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
 392             @header('Pragma: ');
 393         } else { //normal http - prevent caching at all cost
 394             @header('Cache-Control: private, must-revalidate, pre-check=0, post-check=0, max-age=0');
 395             @header('Expires: '. gmdate('D, d M Y H:i:s', 0) .' GMT');
 396             @header('Pragma: no-cache');
 397         }
 398         @header('Accept-Ranges: none'); // Do not allow byteserving when caching disabled
 399     }
 400
 401     if (empty($filter)) {
 402         if ($mimetype == 'text/html' && !empty($CFG->usesid) && empty($_COOKIE['MoodleSession'.$CFG->sessioncookie])) {
 403             //cookieless mode - rewrite links
 404             @header('Content-Type: text/html');
 405             $path = $pathisstring ? $path : implode('', file($path));
 406             $path = sid_ob_rewrite($path);
 407             $filesize = strlen($path);
 408             $pathisstring = true;
 409         } else if ($mimetype == 'text/plain') {
 410             @header('Content-Type: Text/plain; charset=utf-8'); //add encoding
 411         } else {
 412             @header('Content-Type: '.$mimetype);
 413         }
 414         @header('Content-Length: '.$filesize);
 415         while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 416         if ($pathisstring) {
 417             echo $path;
 418         } else {
 419             readfile_chunked($path);
 420         }
 421     } else {     // Try to put the file through filters
 422         if ($mimetype == 'text/html') {
 423             $options = new object();
 424             $options->noclean = true;
 425             $options->nocache = true; // temporary workaround for MDL-5136
 426             $text = $pathisstring ? $path : implode('', file($path));
 427
 428             $text = file_modify_html_header($text);
 429             $output = format_text($text, FORMAT_HTML, $options, $COURSE->id);
 430             if (!empty($CFG->usesid) && empty($_COOKIE['MoodleSession'.$CFG->sessioncookie])) {
 431                 //cookieless mode - rewrite links
 432                 $output = sid_ob_rewrite($output);
 433             }
 434
 435             @header('Content-Length: '.strlen($output));
 436             @header('Content-Type: text/html');
 437             while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 438             echo $output;
 439         // only filter text if filter all files is selected
 440         } else if (($mimetype == 'text/plain') and ($filter == 1)) {
 441             $options = new object();
 442             $options->newlines = false;
 443             $options->noclean = true;
 444             $text = htmlentities($pathisstring ? $path : implode('', file($path)));
 445             $output = '<pre>'. format_text($text, FORMAT_MOODLE, $options, $COURSE->id) .'</pre>';
 446             if (!empty($CFG->usesid) && empty($_COOKIE['MoodleSession'.$CFG->sessioncookie])) {
 447                 //cookieless mode - rewrite links
 448                 $output = sid_ob_rewrite($output);
 449             }
 450
 451             @header('Content-Length: '.strlen($output));
 452             @header('Content-Type: text/html; charset=utf-8'); //add encoding
 453             while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 454             echo $output;
 455         } else {    // Just send it out raw
 456             @header('Content-Length: '.$filesize);
 457             @header('Content-Type: '.$mimetype);
 458             while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 459             if ($pathisstring) {
 460                 echo $path;
 461             }else {
 462                 readfile_chunked($path);
 463             }
 464         }
 465     }
 466     die; //no more chars to output!!!
 467 }
 468
 469 function get_records_csv($file, $table) {
 470     global $CFG, $db;
 471
 472     if (!$metacolumns = $db->MetaColumns($CFG->prefix . $table)) {
 473         return false;
 474     }
 475
 476     if(!($handle = @fopen($file, 'r'))) {
 477         error('get_records_csv failed to open '.$file);
 478     }
 479
 480     $fieldnames = fgetcsv($handle, 4096);
 481     if(empty($fieldnames)) {
 482         fclose($handle);
 483         return false;
 484     }
 485
 486     $columns = array();
 487
 488     foreach($metacolumns as $metacolumn) {
 489         $ord = array_search($metacolumn->name, $fieldnames);
 490         if(is_int($ord)) {
 491             $columns[$metacolumn->name] = $ord;
 492         }
 493     }
 494
 495     $rows = array();
 496
 497     while (($data = fgetcsv($handle, 4096)) !== false) {
 498         $item = new stdClass;
 499         foreach($columns as $name => $ord) {
 500             $item->$name = $data[$ord];
 501         }
 502         $rows[] = $item;
 503     }
 504
 505     fclose($handle);
 506     return $rows;
 507 }
 508
 509 function put_records_csv($file, $records, $table = NULL) {
 510     global $CFG, $db;
 511
 512     if (empty($records)) {
 513         return true;
 514     }
 515
 516     $metacolumns = NULL;
 517     if ($table !== NULL && !$metacolumns = $db->MetaColumns($CFG->prefix . $table)) {
 518         return false;
 519     }
 520
 521     echo "x";
 522
 523     if(!($fp = @fopen($CFG->dataroot.'/temp/'.$file, 'w'))) {
 524         error('put_records_csv failed to open '.$file);
 525     }
 526
 527     $proto = reset($records);
 528     if(is_object($proto)) {
 529         $fields_records = array_keys(get_object_vars($proto));
 530     }
 531     else if(is_array($proto)) {
 532         $fields_records = array_keys($proto);
 533     }
 534     else {
 535         return false;
 536     }
 537     echo "x";
 538
 539     if(!empty($metacolumns)) {
 540         $fields_table = array_map(create_function('$a', 'return $a->name;'), $metacolumns);
 541         $fields = array_intersect($fields_records, $fields_table);
 542     }
 543     else {
 544         $fields = $fields_records;
 545     }
 546
 547     fwrite($fp, implode(',', $fields));
 548     fwrite($fp, "\r\n");
 549
 550     foreach($records as $record) {
 551         $array  = (array)$record;
 552         $values = array();
 553         foreach($fields as $field) {
 554             if(strpos($array[$field], ',')) {
 555                 $values[] = '"'.str_replace('"', '\"', $array[$field]).'"';
 556             }
 557             else {
 558                 $values[] = $array[$field];
 559             }
 560         }
 561         fwrite($fp, implode(',', $values)."\r\n");
 562     }
 563
 564     fclose($fp);
 565     return true;
 566 }
 567
 568
 569 /**
 570  * Recursively delete the file or folder with path $location. That is,
 571  * if it is a file delete it. If it is a folder, delete all its content
 572  * then delete it. If $location does not exist to start, that is not
 573  * considered an error.
 574  *
 575  * @param $location the path to remove.
 576  */
 577 function fulldelete($location) {
 578     if (is_dir($location)) {
 579         $currdir = opendir($location);
 580         while (false !== ($file = readdir($currdir))) {
 581             if ($file <> ".." && $file <> ".") {
 582                 $fullfile = $location."/".$file;
 583                 if (is_dir($fullfile)) {
 584                     if (!fulldelete($fullfile)) {
 585                         return false;
 586                     }
 587                 } else {
 588                     if (!unlink($fullfile)) {
 589                         return false;
 590                     }
 591                 }
 592             }
 593         }
 594         closedir($currdir);
 595         if (! rmdir($location)) {
 596             return false;
 597         }
 598
 599     } else if (file_exists($location)) {
 600         if (!unlink($location)) {
 601             return false;
 602         }
 603     }
 604     return true;
 605 }
 606
 607 /**
 608  * Improves memory consumptions and works around buggy readfile() in PHP 5.0.4 (2MB readfile limit).
 609  */
 610 function readfile_chunked($filename, $retbytes=true) {
 611     $chunksize = 1*(1024*1024); // 1MB chunks - must be less than 2MB!
 612     $buffer = '';
 613     $cnt =0;
 614     $handle = fopen($filename, 'rb');
 615     if ($handle === false) {
 616         return false;
 617     }
 618
 619     while (!feof($handle)) {
 620         @set_time_limit(60*60); //reset time limit to 60 min - should be enough for 1 MB chunk
 621         $buffer = fread($handle, $chunksize);
 622         echo $buffer;
 623         flush();
 624         if ($retbytes) {
 625             $cnt += strlen($buffer);
 626         }
 627     }
 628     $status = fclose($handle);
 629     if ($retbytes && $status) {
 630         return $cnt; // return num. bytes delivered like readfile() does.
 631     }
 632     return $status;
 633 }
 634
 635 /**
 636  * Send requested byterange of file.
 637  */
 638 function byteserving_send_file($filename, $mimetype, $ranges) {
 639     $chunksize = 1*(1024*1024); // 1MB chunks - must be less than 2MB!
 640     $handle = fopen($filename, 'rb');
 641     if ($handle === false) {
 642         die;
 643     }
 644     if (count($ranges) == 1) { //only one range requested
 645         $length = $ranges[0][2] - $ranges[0][1] + 1;
 646         @header('HTTP/1.1 206 Partial content');
 647         @header('Content-Length: '.$length);
 648         @header('Content-Range: bytes '.$ranges[0][1].'-'.$ranges[0][2].'/'.filesize($filename));
 649         @header('Content-Type: '.$mimetype);
 650         while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 651         $buffer = '';
 652         fseek($handle, $ranges[0][1]);
 653         while (!feof($handle) && $length > 0) {
 654             @set_time_limit(60*60); //reset time limit to 60 min - should be enough for 1 MB chunk
 655             $buffer = fread($handle, ($chunksize < $length ? $chunksize : $length));
 656             echo $buffer;
 657             flush();
 658             $length -= strlen($buffer);
 659         }
 660         fclose($handle);
 661         die;
 662     } else { // multiple ranges requested - not tested much
 663         $totallength = 0;
 664         foreach($ranges as $range) {
 665             $totallength += strlen($range[0]) + $range[2] - $range[1] + 1;
 666         }
 667         $totallength += strlen("\r\n--".BYTESERVING_BOUNDARY."--\r\n");
 668         @header('HTTP/1.1 206 Partial content');
 669         @header('Content-Length: '.$totallength);
 670         @header('Content-Type: multipart/byteranges; boundary='.BYTESERVING_BOUNDARY);
 671         //TODO: check if "multipart/x-byteranges" is more compatible with current readers/browsers/servers
 672         while (@ob_end_flush()); //flush the buffers - save memory and disable sid rewrite
 673         foreach($ranges as $range) {
 674             $length = $range[2] - $range[1] + 1;
 675             echo $range[0];
 676             $buffer = '';
 677             fseek($handle, $range[1]);
 678             while (!feof($handle) && $length > 0) {
 679                 @set_time_limit(60*60); //reset time limit to 60 min - should be enough for 1 MB chunk
 680                 $buffer = fread($handle, ($chunksize < $length ? $chunksize : $length));
 681                 echo $buffer;
 682                 flush();
 683                 $length -= strlen($buffer);
 684             }
 685         }
 686         echo "\r\n--".BYTESERVING_BOUNDARY."--\r\n";
 687         fclose($handle);
 688         die;
 689     }
 690 }
 691
 692 /**
 693  * add includes (js and css) into uploaded files
 694  * before returning them, useful for themes and utf.js includes
 695  * @param string text - text to search and replace
 696  * @return string - text with added head includes
 697  */
 698 function file_modify_html_header($text) {
 699     // first look for <head> tag
 700     global $CFG;
 701
 702     $stylesheetshtml = '';
 703     foreach ($CFG->stylesheets as $stylesheet) {
 704         $stylesheetshtml .= '<link rel="stylesheet" type="text/css" href="'.$stylesheet.'" />'."\n";
 705     }
 706
 707     $filters = explode(",", $CFG->textfilters);
 708     if (in_array('filter/mediaplugin', $filters)) {
 709         // this script is needed by most media filter plugins.
 710         $ufo = "\n".'<script type="text/javascript" src="'.$CFG->wwwroot.'/lib/ufo.js"></script>'."\n";
 711     } else {
 712         $ufo = '';
 713     }
 714
 715     preg_match('/\<head\>|\<HEAD\>/', $text, $matches);
 716     if ($matches) {
 717         $replacement = '<head>'.$ufo.$stylesheetshtml;
 718         $text = preg_replace('/\<head\>|\<HEAD\>/', $replacement, $text, 1);
 719         return $text;
 720     }
 721
 722     // if not, look for <html> tag, and stick <head> right after
 723     preg_match('/\<html\>|\<HTML\>/', $text, $matches);
 724     if ($matches) {
 725         // replace <html> tag with <html><head>includes</head>
 726         $replacement = '<html>'."\n".'<head>'.$ufo.$stylesheetshtml.'</head>';
 727         $text = preg_replace('/\<html\>|\<HTML\>/', $replacement, $text, 1);
 728         return $text;
 729     }
 730
 731     // if not, look for <body> tag, and stick <head> before body
 732     preg_match('/\<body\>|\<BODY\>/', $text, $matches);
 733     if ($matches) {
 734         $replacement = '<head>'.$ufo.$stylesheetshtml.'</head>'."\n".'<body>';
 735         $text = preg_replace('/\<body\>|\<BODY\>/', $replacement, $text, 1);
 736         return $text;
 737     }
 738
 739     // if not, just stick a <head> tag at the beginning
 740     $text = '<head>'.$ufo.$stylesheetshtml.'</head>'."\n".$text;
 741     return $text;
 742 }
 743
 744 ?>