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::makeTitleSafe( NS_FILE, $bits[1] );
  59                 if( is_null($title) ) {
  60                         wfThumbError( 404, wfMsg( 'badtitletext' ) );
  61                         return;
  62                 }
  63                 $img = RepoGroup::singleton()->getLocalRepo()->newFromArchiveName( $title, $fileName );
  64         } else {
  65                 $img = wfLocalFile( $fileName );
  66         }
  67
  68         if ( !$img ) {
  69                 wfThumbError( 404, wfMsg( 'badtitletext' ) );
  70                 return;
  71         }
  72         if ( !$img->exists() ) {
  73                 wfThumbError( 404, 'The source file for the specified thumbnail does not exist.' );
  74                 return;
  75         }
  76         $sourcePath = $img->getPath();
  77         if ( $sourcePath === false ) {
  78                 wfThumbError( 500, 'The source file is not locally accessible.' );
  79                 return;
  80         }
  81
  82         // Check IMS against the source file
  83         // This means that clients can keep a cached copy even after it has been deleted on the server
  84         if ( !empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ) {
  85                 // Fix IE brokenness
  86                 $imsString = preg_replace( '/;.*$/', '', $_SERVER["HTTP_IF_MODIFIED_SINCE"] );
  87                 // Calculate time
  88                 wfSuppressWarnings();
  89                 $imsUnix = strtotime( $imsString );
  90                 wfRestoreWarnings();
  91                 $stat = @stat( $sourcePath );
  92                 if ( $stat['mtime'] <= $imsUnix ) {
  93                         header( 'HTTP/1.1 304 Not Modified' );
  94                         return;
  95                 }
  96         }
  97
  98         // Stream the file if it exists already
  99         try {
 100                 if ( false != ( $thumbName = $img->thumbName( $params ) ) ) {
 101                         $thumbPath = $img->getThumbPath( $thumbName );
 102
 103                         if ( is_file( $thumbPath ) ) {
 104                                 wfStreamFile( $thumbPath );
 105                                 return;
 106                         }
 107                 }
 108         } catch ( MWException $e ) {
 109                 wfThumbError( 500, $e->getHTML() );
 110                 return;
 111         }
 112
 113         try {
 114                 $thumb = $img->transform( $params, File::RENDER_NOW );
 115         } catch( Exception $ex ) {
 116                 // Tried to select a page on a non-paged file?
 117                 $thumb = false;
 118         }
 119
 120         $errorMsg = false;
 121         if ( !$thumb ) {
 122                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'File::transform() returned false' );
 123         } elseif ( $thumb->isError() ) {
 124                 $errorMsg = $thumb->getHtmlMsg();
 125         } elseif ( !$thumb->getPath() ) {
 126                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'No path supplied in thumbnail object' );
 127         } elseif ( $thumb->getPath() == $img->getPath() ) {
 128                 $errorMsg = wfMsgHtml( 'thumbnail_error', 'Image was not scaled, ' .
 129                         'is the requested width bigger than the source?' );
 130         } else {
 131                 wfStreamFile( $thumb->getPath() );
 132         }
 133         if ( $errorMsg !== false ) {
 134                 wfThumbError( 500, $errorMsg );
 135         }
 136
 137         wfProfileOut( __METHOD__ );
 138 }
 139
 140 function wfThumbError( $status, $msg ) {
 141         global $wgShowHostnames;
 142         header( 'Cache-Control: no-cache' );
 143         header( 'Content-Type: text/html; charset=utf-8' );
 144         if ( $status == 404 ) {
 145                 header( 'HTTP/1.1 404 Not found' );
 146         } else {
 147                 header( 'HTTP/1.1 500 Internal server error' );
 148         }
 149         if( $wgShowHostnames ) {
 150                 $url = htmlspecialchars( @$_SERVER['REQUEST_URI'] );
 151                 $hostname = htmlspecialchars( wfHostname() );
 152                 $debug = "<!-- $url -->\n<!-- $hostname -->\n";
 153         } else {
 154                 $debug = "";
 155         }
 156         echo <<<EOT
 157 <html><head><title>Error generating thumbnail</title></head>
 158 <body>
 159 <h1>Error generating thumbnail</h1>
 160 <p>
 161 $msg
 162 </p>
 163 $debug
 164 </body>
 165 </html>
 166
 167 EOT;
 168 }
 169