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         // Is this a thumb of an archived file?
  44         $isOld = (isset( $params['archived'] ) && $params['archived']);
  45         unset( $params['archived'] );
  46
  47         // Some basic input validation
  48         $fileName = strtr( $fileName, '\\/', '__' );
  49
  50         // Actually fetch the image. Method depends on whether it is archived or not.
  51         if( $isOld ) {
  52                 // Format is <timestamp>!<name>
  53                 $bits = explode( '!', $fileName, 2 );
  54                 if( !isset($bits[1]) ) {
  55                         wfThumbError( 404, wfMsg( 'badtitletext' ) );
  56                         return;
  57                 }
  58                 $title = Title::makeTitle( NS_IMAGE, $bits[1] );
  59                 $img = RepoGroup::singleton()->getLocalRepo()->newFromArchiveName( $title, $fileName );
  60         } else {
  61                 $img = wfLocalFile( $fileName );
  62         }
  63
  64         if ( !$img ) {
  65                 wfThumbError( 404, wfMsg( 'badtitletext' ) );
  66                 return;
  67         }
  68         if ( !$img->exists() ) {
  69                 wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
  70                 return;
  71         }
  72         $sourcePath = $img->getPath();
  73         if ( $sourcePath === false ) {
  74                 wfThumbError( 500, 'The source file is not locally accessible.' );
  75                 return;
  76         }
  77
  78         // Check IMS against the source file
  79         // This means that clients can keep a cached copy even after it has been deleted on the server
  80         if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
  81                 // Fix IE brokenness
  82                 $imsString = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
  83                 // Calculate time
  84                 wfSuppressWarnings();
  85                 $imsUnix = strtotime( $imsString );
  86                 wfRestoreWarnings();
  87                 $stat = @stat( $sourcePath );
  88                 if ( $stat['mtime'] <= $imsUnix ) {
  89                         header( 'HTTP/1.1 304 Not Modified' );
  90                         return;
  91                 }
  92         }
  93
  94         // Stream the file if it exists already
  95         try {
  96                 if ( false != ( $thumbName = $img->thumbName( $params ) ) ) {
  97                         $thumbPath = $img->getThumbPath( $thumbName );
  98
  99                         if ( is_file( $thumbPath ) ) {
 100                                 wfStreamFile( $thumbPath );
 101                                 return;
 102                         }
 103                 }
 104         } catch ( MWException $e ) {
 105                 wfThumbError( 500, $e->getHTML() );
 106                 return;
 107         }
 108
 109         try {
 110                 $thumb = $img->transform( $params, File::RENDER_NOW );
 111         } catch( Exception $ex ) {
 112                 // Tried to select a page on a non-paged file?
 113                 $thumb = false;
 114         }
 115
 116         $errorMsg = false;
 117         if ( !$thumb ) {
 118                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'File::transform() returned false' );
 119         } elseif ( $thumb->isError() ) {
 120                 $errorMsg = $thumb->getHtmlMsg();
 121         } elseif ( !$thumb->getPath() ) {
 122                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'No path supplied in thumbnail object' );
 123         } elseif ( $thumb->getPath() == $img->getPath() ) {
 124                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'Image was not scaled, ' .
 125                         'is the requested width bigger than the source?' );
 126         } else {
 127                 wfStreamFile( $thumb->getPath() );
 128         }
 129         if ( $errorMsg !== false ) {
 130                 wfThumbError( 500, $errorMsg );
 131         }
 132
 133         wfProfileOut( __METHOD__ );
 134 }
 135
 136 function wfThumbError( $status, $msg ) {
 137         global $wgShowHostnames;
 138         header( 'Cache-Control: no-cache' );
 139         header( 'Content-Type: text/html; charset=utf-8' );
 140         if ( $status == 404 ) {
 141                 header( 'HTTP/1.1 404 Not found' );
 142         } else {
 143                 header( 'HTTP/1.1 500 Internal server error' );
 144         }
 145         if( $wgShowHostnames ) {
 146                 $url = htmlspecialchars( @$_SERVER['REQUEST_URI'] );
 147                 $hostname = htmlspecialchars( wfHostname() );
 148                 $debug = "<!-- $url -->\n<!-- $hostname -->\n";
 149         } else {
 150                 $debug = "";
 151         }
 152         echo <<<EOT
 153 <html><head><title>Error generating thumbnail</title></head>
 154 <body>
 155 <h1>Error generating thumbnail</h1>
 156 <p>
 157 $msg
 158 </p>
 159 $debug
 160 </body>
 161 </html>
 162
 163 EOT;
 164 }
 165