1<?php 2/** 3 * Utilities for handling HTTP related tasks 4 * 5 * @license GPL 2 (http://www.gnu.org/licenses/gpl.html) 6 * @author Andreas Gohr <andi@splitbrain.org> 7 */ 8 9define('HTTP_MULTIPART_BOUNDARY','D0KuW1K1B0uNDARY'); 10define('HTTP_HEADER_LF',"\r\n"); 11define('HTTP_CHUNK_SIZE',16*1024); 12 13/** 14 * Checks and sets HTTP headers for conditional HTTP requests 15 * 16 * @author Simon Willison <swillison@gmail.com> 17 * @link http://simonwillison.net/2003/Apr/23/conditionalGet/ 18 * 19 * @param int $timestamp lastmodified time of the cache file 20 * @returns void or exits with previously header() commands executed 21 */ 22function http_conditionalRequest($timestamp){ 23 // A PHP implementation of conditional get, see 24 // http://fishbowl.pastiche.org/2002/10/21/http_conditional_get_for_rss_hackers/ 25 $last_modified = substr(gmdate('r', $timestamp), 0, -5).'GMT'; 26 $etag = '"'.md5($last_modified).'"'; 27 // Send the headers 28 header("Last-Modified: $last_modified"); 29 header("ETag: $etag"); 30 // See if the client has provided the required headers 31 if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE'])){ 32 $if_modified_since = stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE']); 33 }else{ 34 $if_modified_since = false; 35 } 36 37 if (isset($_SERVER['HTTP_IF_NONE_MATCH'])){ 38 $if_none_match = stripslashes($_SERVER['HTTP_IF_NONE_MATCH']); 39 }else{ 40 $if_none_match = false; 41 } 42 43 if (!$if_modified_since && !$if_none_match){ 44 return; 45 } 46 47 // At least one of the headers is there - check them 48 if ($if_none_match && $if_none_match != $etag) { 49 return; // etag is there but doesn't match 50 } 51 52 if ($if_modified_since && $if_modified_since != $last_modified) { 53 return; // if-modified-since is there but doesn't match 54 } 55 56 // Nothing has changed since their last request - serve a 304 and exit 57 header('HTTP/1.0 304 Not Modified'); 58 59 // don't produce output, even if compression is on 60 @ob_end_clean(); 61 exit; 62} 63 64/** 65 * Let the webserver send the given file via x-sendfile method 66 * 67 * @author Chris Smith <chris@jalakai.co.uk> 68 * 69 * @param string $file absolute path of file to send 70 * @returns void or exits with previous header() commands executed 71 */ 72function http_sendfile($file) { 73 global $conf; 74 75 //use x-sendfile header to pass the delivery to compatible web servers 76 if($conf['xsendfile'] == 1){ 77 header("X-LIGHTTPD-send-file: $file"); 78 ob_end_clean(); 79 exit; 80 }elseif($conf['xsendfile'] == 2){ 81 header("X-Sendfile: $file"); 82 ob_end_clean(); 83 exit; 84 }elseif($conf['xsendfile'] == 3){ 85 header("X-Accel-Redirect: $file"); 86 ob_end_clean(); 87 exit; 88 } 89} 90 91/** 92 * Send file contents supporting rangeRequests 93 * 94 * This function exits the running script 95 * 96 * @param resource $fh - file handle for an already open file 97 * @param int $size - size of the whole file 98 * @param int $mime - MIME type of the file 99 * 100 * @author Andreas Gohr <andi@splitbrain.org> 101 */ 102function http_rangeRequest($fh,$size,$mime){ 103 $ranges = array(); 104 $isrange = false; 105 106 header('Accept-Ranges: bytes'); 107 108 if(!isset($_SERVER['HTTP_RANGE'])){ 109 // no range requested - send the whole file 110 $ranges[] = array(0,$size,$size); 111 }else{ 112 $t = explode('=', $_SERVER['HTTP_RANGE']); 113 if (!$t[0]=='bytes') { 114 // we only understand byte ranges - send the whole file 115 $ranges[] = array(0,$size,$size); 116 }else{ 117 $isrange = true; 118 // handle multiple ranges 119 $r = explode(',',$t[1]); 120 foreach($r as $x){ 121 $p = explode('-', $x); 122 $start = (int)$p[0]; 123 $end = (int)$p[1]; 124 if (!$end) $end = $size - 1; 125 if ($start > $end || $start > $size || $end > $size){ 126 header('HTTP/1.1 416 Requested Range Not Satisfiable'); 127 print 'Bad Range Request!'; 128 exit; 129 } 130 $len = $end - $start + 1; 131 $ranges[] = array($start,$end,$len); 132 } 133 } 134 } 135 $parts = count($ranges); 136 137 // now send the type and length headers 138 if(!$isrange){ 139 header("Content-Type: $mime",true); 140 }else{ 141 header('HTTP/1.1 206 Partial Content'); 142 if($parts == 1){ 143 header("Content-Type: $mime",true); 144 }else{ 145 header('Content-Type: multipart/byteranges; boundary='.HTTP_MULTIPART_BOUNDARY,true); 146 } 147 } 148 149 // send all ranges 150 for($i=0; $i<$parts; $i++){ 151 list($start,$end,$len) = $ranges[$i]; 152 153 // multipart or normal headers 154 if($parts > 1){ 155 echo HTTP_HEADER_LF.'--'.HTTP_MULTIPART_BOUNDARY.HTTP_HEADER_LF; 156 echo "Content-Type: $mime".HTTP_HEADER_LF; 157 echo "Content-Range: bytes $start-$end/$size".HTTP_HEADER_LF; 158 echo HTTP_HEADER_LF; 159 }else{ 160 header("Content-Length: $len"); 161 if($isrange){ 162 header("Content-Range: bytes $start-$end/$size"); 163 } 164 } 165 166 // send file content 167 fseek($fh,$start); //seek to start of range 168 $chunk = ($len > HTTP_CHUNK_SIZE) ? HTTP_CHUNK_SIZE : $len; 169 while (!feof($fh) && $chunk > 0) { 170 @set_time_limit(30); // large files can take a lot of time 171 print fread($fh, $chunk); 172 flush(); 173 $len -= $chunk; 174 $chunk = ($len > HTTP_CHUNK_SIZE) ? HTTP_CHUNK_SIZE : $len; 175 } 176 } 177 if($parts > 1){ 178 echo HTTP_HEADER_LF.'--'.HTTP_MULTIPART_BOUNDARY.'--'.HTTP_HEADER_LF; 179 } 180 181 // everything should be done here, exit (or return if testing) 182 if (defined('SIMPLE_TEST')) return; 183 exit; 184} 185 186/** 187 * Check for a gzipped version and create if necessary 188 * 189 * return true if there exists a gzip version of the uncompressed file 190 * (samepath/samefilename.sameext.gz) created after the uncompressed file 191 * 192 * @author Chris Smith <chris.eureka@jalakai.co.uk> 193 * 194 * @param string $uncompressed_file 195 * @return bool 196 */ 197function http_gzip_valid($uncompressed_file) { 198 if(!DOKU_HAS_GZIP) return false; 199 200 $gzip = $uncompressed_file.'.gz'; 201 if (filemtime($gzip) < filemtime($uncompressed_file)) { // filemtime returns false (0) if file doesn't exist 202 return copy($uncompressed_file, 'compress.zlib://'.$gzip); 203 } 204 205 return true; 206} 207 208/** 209 * Set HTTP headers and echo cachefile, if useable 210 * 211 * This function handles output of cacheable resource files. It ses the needed 212 * HTTP headers. If a useable cache is present, it is passed to the web server 213 * and the script is terminated. 214 * 215 * @param string $cache cache file name 216 * @param bool $cache_ok if cache can be used 217 */ 218function http_cached($cache, $cache_ok) { 219 global $conf; 220 221 // check cache age & handle conditional request 222 // since the resource files are timestamped, we can use a long max age: 1 year 223 header('Cache-Control: public, max-age=31536000'); 224 header('Pragma: public'); 225 if($cache_ok){ 226 http_conditionalRequest(filemtime($cache)); 227 if($conf['allowdebug']) header("X-CacheUsed: $cache"); 228 229 // finally send output 230 if ($conf['gzip_output'] && http_gzip_valid($cache)) { 231 header('Vary: Accept-Encoding'); 232 header('Content-Encoding: gzip'); 233 readfile($cache.".gz"); 234 } else { 235 http_sendfile($cache); 236 readfile($cache); 237 } 238 exit; 239 } 240 241 http_conditionalRequest(time()); 242} 243 244/** 245 * Cache content and print it 246 * 247 * @param string $file file name 248 * @param string $content 249 */ 250function http_cached_finish($file, $content) { 251 global $conf; 252 253 // save cache file 254 io_saveFile($file, $content); 255 if(DOKU_HAS_GZIP) io_saveFile("$file.gz",$content); 256 257 // finally send output 258 if ($conf['gzip_output'] && DOKU_HAS_GZIP) { 259 header('Vary: Accept-Encoding'); 260 header('Content-Encoding: gzip'); 261 print gzencode($content,9,FORCE_GZIP); 262 } else { 263 print $content; 264 } 265} 266 267/** 268 * Fetches raw, unparsed POST data 269 * 270 * @return string 271 */ 272function http_get_raw_post_data() { 273 static $postData = null; 274 if ($postData === null) { 275 $postData = file_get_contents('php://input'); 276 } 277 return $postData; 278} 279 280/** 281 * Set the HTTP response status and takes care of the used PHP SAPI 282 * 283 * Inspired by CodeIgniter's set_status_header function 284 * 285 * @param int $code 286 * @param string $text 287 */ 288function http_status($code = 200, $text = '') { 289 static $stati = array( 290 200 => 'OK', 291 201 => 'Created', 292 202 => 'Accepted', 293 203 => 'Non-Authoritative Information', 294 204 => 'No Content', 295 205 => 'Reset Content', 296 206 => 'Partial Content', 297 298 300 => 'Multiple Choices', 299 301 => 'Moved Permanently', 300 302 => 'Found', 301 304 => 'Not Modified', 302 305 => 'Use Proxy', 303 307 => 'Temporary Redirect', 304 305 400 => 'Bad Request', 306 401 => 'Unauthorized', 307 403 => 'Forbidden', 308 404 => 'Not Found', 309 405 => 'Method Not Allowed', 310 406 => 'Not Acceptable', 311 407 => 'Proxy Authentication Required', 312 408 => 'Request Timeout', 313 409 => 'Conflict', 314 410 => 'Gone', 315 411 => 'Length Required', 316 412 => 'Precondition Failed', 317 413 => 'Request Entity Too Large', 318 414 => 'Request-URI Too Long', 319 415 => 'Unsupported Media Type', 320 416 => 'Requested Range Not Satisfiable', 321 417 => 'Expectation Failed', 322 323 500 => 'Internal Server Error', 324 501 => 'Not Implemented', 325 502 => 'Bad Gateway', 326 503 => 'Service Unavailable', 327 504 => 'Gateway Timeout', 328 505 => 'HTTP Version Not Supported' 329 ); 330 331 if($text == '' && isset($stati[$code])) { 332 $text = $stati[$code]; 333 } 334 335 $server_protocol = (isset($_SERVER['SERVER_PROTOCOL'])) ? $_SERVER['SERVER_PROTOCOL'] : false; 336 337 if(substr(php_sapi_name(), 0, 3) == 'cgi' || defined('SIMPLE_TEST')) { 338 header("Status: {$code} {$text}", true); 339 } elseif($server_protocol == 'HTTP/1.1' OR $server_protocol == 'HTTP/1.0') { 340 header($server_protocol." {$code} {$text}", true, $code); 341 } else { 342 header("HTTP/1.1 {$code} {$text}", true, $code); 343 } 344} 345