(bug 33471) compare detectProtocol to 'https'
[lhc/web/wiklou.git] / includes / StreamFile.php
index ae4ca4e..95c69a2 100644 (file)
 <?php
 /**
- * Functions related to the output of file content
+ * Functions related to the output of file content.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
  *
  * @file
  */
 
-/** */
-function wfStreamFile( $fname, $headers = array() ) {
-       $stat = @stat( $fname );
-       if ( !$stat ) {
-               header( 'HTTP/1.0 404 Not Found' );
-               header( 'Cache-Control: no-cache' );
-               header( 'Content-Type: text/html; charset=utf-8' );
-               $encFile = htmlspecialchars( $fname );
-               $encScript = htmlspecialchars( $_SERVER['SCRIPT_NAME'] );
-               echo "<html><body>
-<h1>File not found</h1>
-<p>Although this PHP script ($encScript) exists, the file requested for output
-($encFile) does not.</p>
-</body></html>
-";
-               return;
-       }
+/**
+ * Functions related to the output of file content
+ */
+class StreamFile {
+       const READY_STREAM = 1;
+       const NOT_MODIFIED = 2;
 
-       header( 'Last-Modified: ' . gmdate( 'D, d M Y H:i:s', $stat['mtime'] ) . ' GMT' );
+       /**
+        * Stream a file to the browser, adding all the headings and fun stuff.
+        * Headers sent include: Content-type, Content-Length, Last-Modified,
+        * and Content-Disposition.
+        *
+        * @param $fname string Full name and path of the file to stream
+        * @param $headers array Any additional headers to send
+        * @param $sendErrors bool Send error messages if errors occur (like 404)
+        * @return bool Success
+        */
+       public static function stream( $fname, $headers = array(), $sendErrors = true ) {
+               wfProfileIn( __METHOD__ );
 
-       // Cancel output buffering and gzipping if set
-       wfResetOutputBuffers();
+               if ( FileBackend::isStoragePath( $fname ) ) { // sanity
+                       throw new MWException( __FUNCTION__ . " given storage path '$fname'." );
+               }
 
-       $type = wfGetType( $fname );
-       if ( $type and $type!="unknown/unknown") {
-               header("Content-type: $type");
-       } else {
-               header('Content-type: application/x-wiki');
-       }
+               wfSuppressWarnings();
+               $stat = stat( $fname );
+               wfRestoreWarnings();
 
-       // Don't stream it out as text/html if there was a PHP error
-       if ( headers_sent() ) {
-               echo "Headers already sent, terminating.\n";
-               return;
+               $res = self::prepareForStream( $fname, $stat, $headers, $sendErrors );
+               if ( $res == self::NOT_MODIFIED ) {
+                       $ok = true; // use client cache
+               } elseif ( $res == self::READY_STREAM ) {
+                       wfProfileIn( __METHOD__ . '-send' );
+                       $ok = readfile( $fname );
+                       wfProfileOut( __METHOD__ . '-send' );
+               } else {
+                       $ok = false; // failed
+               }
+
+               wfProfileOut( __METHOD__ );
+               return $ok;
        }
 
-       global $wgLanguageCode;
-       header( "Content-Disposition: inline;filename*=utf-8'$wgLanguageCode'" . urlencode( basename( $fname ) ) );
+       /**
+        * Call this function used in preparation before streaming a file.
+        * This function does the following:
+        * (a) sends Last-Modified, Content-type, and Content-Disposition headers
+        * (b) cancels any PHP output buffering and automatic gzipping of output
+        * (c) sends Content-Length header based on HTTP_IF_MODIFIED_SINCE check
+        *
+        * @param $path string Storage path or file system path
+        * @param $info Array|bool File stat info with 'mtime' and 'size' fields
+        * @param $headers Array Additional headers to send
+        * @param $sendErrors bool Send error messages if errors occur (like 404)
+        * @return int|bool READY_STREAM, NOT_MODIFIED, or false on failure
+        */
+       public static function prepareForStream(
+               $path, $info, $headers = array(), $sendErrors = true
+       ) {
+               if ( !is_array( $info ) ) {
+                       if ( $sendErrors ) {
+                               header( 'HTTP/1.0 404 Not Found' );
+                               header( 'Cache-Control: no-cache' );
+                               header( 'Content-Type: text/html; charset=utf-8' );
+                               $encFile = htmlspecialchars( $path );
+                               $encScript = htmlspecialchars( $_SERVER['SCRIPT_NAME'] );
+                               echo "<html><body>
+                                       <h1>File not found</h1>
+                                       <p>Although this PHP script ($encScript) exists, the file requested for output
+                                       ($encFile) does not.</p>
+                                       </body></html>
+                                       ";
+                       }
+                       return false;
+               }
+
+               // Sent Last-Modified HTTP header for client-side caching
+               header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $info['mtime'] ) );
 
-       foreach ( $headers as $header ) {
-               header( $header );
-       }
+               // Cancel output buffering and gzipping if set
+               wfResetOutputBuffers();
 
-       if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
-               $modsince = preg_replace( '/;.*$/', '', $_SERVER['HTTP_IF_MODIFIED_SINCE'] );
-               $sinceTime = strtotime( $modsince );
-               if ( $stat['mtime'] <= $sinceTime ) {
-                       ini_set('zlib.output_compression', 0);
-                       header( "HTTP/1.0 304 Not Modified" );
-                       return;
+               $type = self::contentTypeFromPath( $path );
+               if ( $type && $type != 'unknown/unknown' ) {
+                       header( "Content-type: $type" );
+               } else {
+                       // Send a content type which is not known to Internet Explorer, to
+                       // avoid triggering IE's content type detection. Sending a standard
+                       // unknown content type here essentially gives IE license to apply
+                       // whatever content type it likes.
+                       header( 'Content-type: application/x-wiki' );
                }
-       }
 
-       header( 'Content-Length: ' . $stat['size'] );
+               // Don't stream it out as text/html if there was a PHP error
+               if ( headers_sent() ) {
+                       echo "Headers already sent, terminating.\n";
+                       return false;
+               }
 
-       readfile( $fname );
-}
+               // Send additional headers
+               foreach ( $headers as $header ) {
+                       header( $header );
+               }
 
-/** */
-function wfGetType( $filename, $safe = true ) {
-       global $wgTrivialMimeDetection;
-
-       $ext = strrchr($filename, '.');
-       $ext = $ext === false ? '' : strtolower( substr( $ext, 1 ) );
-
-       # trivial detection by file extension,
-       # used for thumbnails (thumb.php)
-       if ($wgTrivialMimeDetection) {
-               switch ($ext) {
-                       case 'gif': return 'image/gif';
-                       case 'png': return 'image/png';
-                       case 'jpg': return 'image/jpeg';
-                       case 'jpeg': return 'image/jpeg';
+               // Don't send if client has up to date cache
+               if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
+                       $modsince = preg_replace( '/;.*$/', '', $_SERVER['HTTP_IF_MODIFIED_SINCE'] );
+                       if ( wfTimestamp( TS_UNIX, $info['mtime'] ) <= strtotime( $modsince ) ) {
+                               ini_set( 'zlib.output_compression', 0 );
+                               header( "HTTP/1.0 304 Not Modified" );
+                               return self::NOT_MODIFIED; // ok
+                       }
                }
 
-               return 'unknown/unknown';
+               header( 'Content-Length: ' . $info['size'] );
+
+               return self::READY_STREAM; // ok
        }
-       
-       $magic = MimeMagic::singleton();
-       // Use the extension only, rather than magic numbers, to avoid opening 
-       // up vulnerabilities due to uploads of files with allowed extensions
-       // but disallowed types.
-       $type = $magic->guessTypesForExtension( $ext );
 
        /**
-        * Double-check some security settings that were done on upload but might 
-        * have changed since.
+        * Determine the file type of a file based on the path
+        *
+        * @param $filename string Storage path or file system path
+        * @param $safe bool Whether to do retroactive upload blacklist checks
+        * @return null|string
         */
-       if ( $safe ) {
-               global $wgFileBlacklist, $wgCheckFileExtensions, $wgStrictFileExtensions, 
-                       $wgFileExtensions, $wgVerifyMimeType, $wgMimeTypeBlacklist;
-               list( $partName, $extList ) = UploadBase::splitExtensions( $filename );
-               if ( UploadBase::checkFileExtensionList( $extList, $wgFileBlacklist ) ) {
-                       return 'unknown/unknown';
-               }
-               if ( $wgCheckFileExtensions && $wgStrictFileExtensions 
-                       && !UploadBase::checkFileExtensionList( $extList, $wgFileExtensions ) )
-               {
+       public static function contentTypeFromPath( $filename, $safe = true ) {
+               global $wgTrivialMimeDetection;
+
+               $ext = strrchr( $filename, '.' );
+               $ext = $ext === false ? '' : strtolower( substr( $ext, 1 ) );
+
+               # trivial detection by file extension,
+               # used for thumbnails (thumb.php)
+               if ( $wgTrivialMimeDetection ) {
+                       switch ( $ext ) {
+                               case 'gif': return 'image/gif';
+                               case 'png': return 'image/png';
+                               case 'jpg': return 'image/jpeg';
+                               case 'jpeg': return 'image/jpeg';
+                       }
+
                        return 'unknown/unknown';
                }
-               if ( $wgVerifyMimeType && in_array( strtolower( $type ), $wgMimeTypeBlacklist ) ) {
-                       return 'unknown/unknown';
+
+               $magic = MimeMagic::singleton();
+               // Use the extension only, rather than magic numbers, to avoid opening
+               // up vulnerabilities due to uploads of files with allowed extensions
+               // but disallowed types.
+               $type = $magic->guessTypesForExtension( $ext );
+
+               /**
+                * Double-check some security settings that were done on upload but might
+                * have changed since.
+                */
+               if ( $safe ) {
+                       global $wgFileBlacklist, $wgCheckFileExtensions, $wgStrictFileExtensions,
+                               $wgFileExtensions, $wgVerifyMimeType, $wgMimeTypeBlacklist;
+                       list( , $extList ) = UploadBase::splitExtensions( $filename );
+                       if ( UploadBase::checkFileExtensionList( $extList, $wgFileBlacklist ) ) {
+                               return 'unknown/unknown';
+                       }
+                       if ( $wgCheckFileExtensions && $wgStrictFileExtensions
+                               && !UploadBase::checkFileExtensionList( $extList, $wgFileExtensions ) )
+                       {
+                               return 'unknown/unknown';
+                       }
+                       if ( $wgVerifyMimeType && in_array( strtolower( $type ), $wgMimeTypeBlacklist ) ) {
+                               return 'unknown/unknown';
+                       }
                }
+               return $type;
        }
-       return $type;
 }