thumb.php

   1 <?php
   2
   3 /**
   4  * PHP script to stream out an image thumbnail.
   5  *
   6  * @file
   7  * @ingroup Media
   8  */
   9 define( 'MW_NO_OUTPUT_COMPRESSION', 1 );
  10 require_once( './includes/WebStart.php' );
  11
  12 $wgTrivialMimeDetection = true; //don't use fancy mime detection, just check the file extension for jpg/gif/png.
  13
  14 require_once( "$IP/includes/StreamFile.php" );
  15
  16 wfThumbMain();
  17 wfLogProfilingData();
  18
  19 //--------------------------------------------------------------------------
  20
  21 function wfThumbMain() {
  22         wfProfileIn( __METHOD__ );
  23         // Get input parameters
  24         if ( get_magic_quotes_gpc() ) {
  25                 $params = array_map( 'stripslashes', $_REQUEST );
  26         } else {
  27                 $params = $_REQUEST;
  28         }
  29
  30         $fileName = isset( $params['f'] ) ? $params['f'] : '';
  31         unset( $params['f'] );
  32
  33         // Backwards compatibility parameters
  34         if ( isset( $params['w'] ) ) {
  35                 $params['width'] = $params['w'];
  36                 unset( $params['w'] );
  37         }
  38         if ( isset( $params['p'] ) ) {
  39                 $params['page'] = $params['p'];
  40         }
  41         unset( $params['r'] );
  42
  43         // Some basic input validation
  44         $fileName = strtr( $fileName, '\\/', '__' );
  45
  46         $img = wfLocalFile( $fileName );
  47         if ( !$img ) {
  48                 wfThumbError( 404, wfMsg( 'badtitletext' ) );
  49                 return;
  50         }
  51         if ( !$img->exists() ) {
  52                 wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
  53                 return;
  54         }
  55         $sourcePath = $img->getPath();
  56         if ( $sourcePath === false ) {
  57                 wfThumbError( 500, 'The source file is not locally accessible.' );
  58                 return;
  59         }
  60
  61         // Check IMS against the source file
  62         // This means that clients can keep a cached copy even after it has been deleted on the server
  63         if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
  64                 // Fix IE brokenness
  65                 $imsString = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
  66                 // Calculate time
  67                 wfSuppressWarnings();
  68                 $imsUnix = strtotime( $imsString );
  69                 wfRestoreWarnings();
  70                 $stat = @stat( $sourcePath );
  71                 if ( $stat['mtime'] <= $imsUnix ) {
  72                         header( 'HTTP/1.1 304 Not Modified' );
  73                         return;
  74                 }
  75         }
  76
  77         // Stream the file if it exists already
  78         try {
  79                 if ( false != ( $thumbName = $img->thumbName( $params ) ) ) {
  80                         $thumbPath = $img->getThumbPath( $thumbName );
  81
  82                         if ( is_file( $thumbPath ) ) {
  83                                 wfStreamFile( $thumbPath );
  84                                 return;
  85                         }
  86                 }
  87         } catch ( MWException $e ) {
  88                 wfThumbError( 500, $e->getHTML() );
  89                 return;
  90         }
  91
  92         try {
  93                 $thumb = $img->transform( $params, File::RENDER_NOW );
  94         } catch( Exception $ex ) {
  95                 // Tried to select a page on a non-paged file?
  96                 $thumb = false;
  97         }
  98
  99         $errorMsg = false;
 100         if ( !$thumb ) {
 101                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'File::transform() returned false' );
 102         } elseif ( $thumb->isError() ) {
 103                 $errorMsg = $thumb->getHtmlMsg();
 104         } elseif ( !$thumb->getPath() ) {
 105                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'No path supplied in thumbnail object' );
 106         } elseif ( $thumb->getPath() == $img->getPath() ) {
 107                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'Image was not scaled, ' .
 108                         'is the requested width bigger than the source?' );
 109         } else {
 110                 wfStreamFile( $thumb->getPath() );
 111         }
 112         if ( $errorMsg !== false ) {
 113                 wfThumbError( 500, $errorMsg );
 114         }
 115
 116         wfProfileOut( __METHOD__ );
 117 }
 118
 119 function wfThumbError( $status, $msg ) {
 120         global $wgShowHostnames;
 121         header( 'Cache-Control: no-cache' );
 122         header( 'Content-Type: text/html; charset=utf-8' );
 123         if ( $status == 404 ) {
 124                 header( 'HTTP/1.1 404 Not found' );
 125         } else {
 126                 header( 'HTTP/1.1 500 Internal server error' );
 127         }
 128         if( $wgShowHostnames ) {
 129                 $url = htmlspecialchars( @$_SERVER['REQUEST_URI'] );
 130                 $hostname = htmlspecialchars( wfHostname() );
 131                 $debug = "<!-- $url -->\n<!-- $hostname -->\n";
 132         } else {
 133                 $debug = "";
 134         }
 135         echo <<<EOT
 136 <html><head><title>Error generating thumbnail</title></head>
 137 <body>
 138 <h1>Error generating thumbnail</h1>
 139 <p>
 140 $msg
 141 </p>
 142 $debug
 143 </body>
 144 </html>
 145
 146 EOT;
 147 }
 148