thumb.php

   1 <?php
   2
   3 /**
   4  * PHP script to stream out an image thumbnail.
   5  *
   6  * @addtogroup Media
   7  */
   8 define( 'MW_NO_OUTPUT_COMPRESSION', 1 );
   9 require_once( './includes/WebStart.php' );
  10
  11 $wgTrivialMimeDetection = true; //don't use fancy mime detection, just check the file extension for jpg/gif/png.
  12
  13 require_once( "$IP/includes/StreamFile.php" );
  14
  15 wfThumbMain();
  16 wfLogProfilingData();
  17
  18 //--------------------------------------------------------------------------
  19
  20 function wfThumbMain() {
  21         wfProfileIn( __METHOD__ );
  22         // Get input parameters
  23         if ( get_magic_quotes_gpc() ) {
  24                 $params = array_map( 'stripslashes', $_REQUEST );
  25         } else {
  26                 $params = $_REQUEST;
  27         }
  28
  29         $fileName = isset( $params['f'] ) ? $params['f'] : '';
  30         unset( $params['f'] );
  31
  32         // Backwards compatibility parameters
  33         if ( isset( $params['w'] ) ) {
  34                 $params['width'] = $params['w'];
  35                 unset( $params['w'] );
  36         }
  37         if ( isset( $params['p'] ) ) {
  38                 $params['page'] = $params['p'];
  39         }
  40         unset( $params['r'] );
  41
  42         // Some basic input validation
  43         $fileName = strtr( $fileName, '\\/', '__' );
  44
  45         $img = wfLocalFile( $fileName );
  46         if ( !$img ) {
  47                 wfThumbError( 404, wfMsg( 'badtitletext' ) );
  48                 return;
  49         }
  50         if ( !$img->exists() ) {
  51                 wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
  52                 return;
  53         }
  54         $sourcePath = $img->getPath();
  55         if ( $sourcePath === false ) {
  56                 wfThumbError( 500, 'The source file is not locally accessible.' );
  57                 return;
  58         }
  59
  60         // Check IMS against the source file
  61         // This means that clients can keep a cached copy even after it has been deleted on the server
  62         if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
  63                 // Fix IE brokenness
  64                 $imsString = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
  65                 // Calculate time
  66                 wfSuppressWarnings();
  67                 $imsUnix = strtotime( $imsString );
  68                 wfRestoreWarnings();
  69                 $stat = @stat( $sourcePath );
  70                 if ( $stat['mtime'] <= $imsUnix ) {
  71                         header( 'HTTP/1.1 304 Not Modified' );
  72                         return;
  73                 }
  74         }
  75
  76         // Stream the file if it exists already
  77         try {
  78                 if ( false != ( $thumbName = $img->thumbName( $params ) ) ) {
  79                         $thumbPath = $img->getThumbPath( $thumbName );
  80
  81                         if ( is_file( $thumbPath ) ) {
  82                                 wfStreamFile( $thumbPath );
  83                                 return;
  84                         }
  85                 }
  86         } catch ( MWException $e ) {
  87                 wfThumbError( 500, $e->getHTML() );
  88                 return;
  89         }
  90
  91         try {
  92                 $thumb = $img->transform( $params, File::RENDER_NOW );
  93         } catch( Exception $ex ) {
  94                 // Tried to select a page on a non-paged file?
  95                 $thumb = false;
  96         }
  97
  98         $errorMsg = false;
  99         if ( !$thumb ) {
 100                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'File::transform() returned false' );
 101         } elseif ( $thumb->isError() ) {
 102                 $errorMsg = $thumb->getHtmlMsg();
 103         } elseif ( !$thumb->getPath() ) {
 104                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'No path supplied in thumbnail object' );
 105         } elseif ( $thumb->getPath() == $img->getPath() ) {
 106                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'Image was not scaled, ' .
 107                         'is the requested width bigger than the source?' );
 108         } else {
 109                 wfStreamFile( $thumb->getPath() );
 110         }
 111         if ( $errorMsg !== false ) {
 112                 wfThumbError( 500, $errorMsg );
 113         }
 114
 115         wfProfileOut( __METHOD__ );
 116 }
 117
 118 function wfThumbError( $status, $msg ) {
 119         header( 'Cache-Control: no-cache' );
 120         header( 'Content-Type: text/html; charset=utf-8' );
 121         if ( $status == 404 ) {
 122                 header( 'HTTP/1.1 404 Not found' );
 123         } else {
 124                 header( 'HTTP/1.1 500 Internal server error' );
 125         }
 126         echo <<<EOT
 127 <html><head><title>Error generating thumbnail</title></head>
 128 <body>
 129 <h1>Error generating thumbnail</h1>
 130 <p>
 131 $msg
 132 </p>
 133 </body>
 134 </html>
 135
 136 EOT;
 137 }
 138