filter/tex/texed.php

   1 <?PHP // $Id$
   2       // This function fetches math. images from the data directory
   3       // If not, it obtains the corresponding TeX expression from the cache_tex db table
   4       // and uses mimeTeX to create the image file
   5
   6     $nomoodlecookie = true;     // Because it interferes with caching
   7
   8     require_once("../../config.php");
   9
  10     if (empty($CFG->textfilters)) {
  11         error ('Filter not enabled!');
  12     } else {
  13         $filters = explode(',', $CFG->textfilters);
  14         if (array_search('filter/tex', $filters) === FALSE) {
  15             error ('Filter not enabled!');
  16         }
  17     }
  18
  19     $CFG->texfilterdir = "filter/tex";
  20     $CFG->teximagedir = "filter/tex";
  21
  22     error_reporting(E_ALL);
  23     $texexp = urldecode($_SERVER['QUERY_STRING']);
  24     $texexp = str_replace('formdata=','',$texexp);
  25
  26     if ($texexp) {
  27         //$texexp = stripslashes($texexp);
  28         $lifetime = 86400;
  29         $image  = md5($texexp) . ".gif";
  30         $filetype = 'image/gif';
  31         if (!file_exists("$CFG->dataroot/$CFG->teximagedir")) {
  32             make_upload_directory($CFG->teximagedir);
  33         }
  34         $pathname = "$CFG->dataroot/$CFG->teximagedir/$image";
  35         $texexp = escapeshellarg($texexp);
  36
  37         switch (PHP_OS) {
  38             case "Linux":
  39                 system("$CFG->dirroot/$CFG->texfilterdir/mimetex.linux -e $pathname -- $texexp" );
  40             break;
  41             case "WINNT":
  42             case "WIN32":
  43             case "Windows":
  44                 system("$CFG->dirroot/$CFG->texfilterdir/mimetex.exe -e  $pathname -- $texexp");
  45             break;
  46             case "Darwin":
  47                 system("$CFG->dirroot/$CFG->texfilterdir/mimetex.darwin -e $pathname -- $texexp" );
  48             break;
  49         }
  50         if (file_exists($pathname)) {
  51             $lastmodified = filemtime($pathname);
  52             header("Last-Modified: " . gmdate("D, d M Y H:i:s", $lastmodified) . " GMT");
  53             header("Expires: " . gmdate("D, d M Y H:i:s", time() + $lifetime) . " GMT");
  54             header("Cache-control: max_age = $lifetime"); // a day
  55             header("Pragma: ");
  56             header("Content-disposition: inline; filename=$image");
  57             header("Content-length: ".filesize($pathname));
  58             header("Content-type: $filetype");
  59             readfile("$pathname");
  60         } else {
  61             echo "Image not found!";
  62         }
  63         exit;
  64     }
  65
  66 ?>
  67
  68 <html>
  69 <head><title>mimeTeX Previewer</title></head>
  70 <body>
  71     <p>Now enter your own expression or use the sample provided,
  72      press the Submit button, and mimeTeX's rendering should be
  73      displayed in the little window immediately below it.
  74        <center>
  75           <form action="texed.php" method="get"
  76            target="inlineframe">
  77              <input type="text" name="formdata" size="50"
  78                     value="\Large f(x)=\Bigint_{-\infty}^x~e^{-t^2}dt" />
  79              <input type="submit" />
  80           </form> <br /> <br />
  81           <iframe name="inlineframe" align="middle" width="80%" height="100">
  82           &lt;p&gt;Something is wrong...&lt;/p&gt;
  83           </iframe>
  84        </center> <br />
  85 </body>
  86 </html>