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See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.

Differences Between: [Versions 310 and 401] [Versions 311 and 401] [Versions 39 and 401] [Versions 400 and 401]

   1  <?php
   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  // disable moodle specific debug messages and any errors in output
   7  define('NO_DEBUG_DISPLAY', true);
   8  define('NO_MOODLE_COOKIES', true); // Because it interferes with caching
   9  
  10      require_once('../../config.php');
  11  
  12      if (!filter_is_enabled('algebra')) {
  13          throw new \moodle_exception('filternotenabled');
  14      }
  15  
  16      require_once($CFG->libdir.'/filelib.php');
  17      require_once($CFG->dirroot.'/filter/tex/lib.php');
  18  
  19      $cmd    = '';               // Initialise these variables
  20      $status = '';
  21  
  22      $relativepath = get_file_argument();
  23  
  24      $args = explode('/', trim($relativepath, '/'));
  25  
  26      if (count($args) == 1) {
  27          $image    = $args[0];
  28          $pathname = $CFG->dataroot.'/filter/algebra/'.$image;
  29      } else {
  30          throw new \moodle_exception('invalidarguments', 'error');
  31      }
  32  
  33      if (!file_exists($pathname)) {
  34          $md5 = str_replace('.gif','',$image);
  35          if ($texcache = $DB->get_record('cache_filters', array('filter'=>'algebra', 'md5key'=>$md5))) {
  36              if (!file_exists($CFG->dataroot.'/filter/algebra')) {
  37                  make_upload_directory('filter/algebra');
  38              }
  39  
  40              $texexp = $texcache->rawtext;
  41              $texexp = str_replace('&lt;','<',$texexp);
  42              $texexp = str_replace('&gt;','>',$texexp);
  43              $texexp = preg_replace('!\r\n?!',' ',$texexp);
  44              $texexp = '\Large ' . $texexp;
  45              $cmd = filter_tex_get_cmd($pathname, $texexp);
  46              system($cmd, $status);
  47          }
  48      }
  49  
  50      if (file_exists($pathname)) {
  51          send_file($pathname, $image);
  52      } else {
  53          if (debugging()) {
  54              echo "The shell command<br />$cmd<br />returned status = $status<br />\n";
  55              echo "Image not found!<br />";
  56              echo "Please try the <a href=\"$CFG->wwwroot/filter/algebra/algebradebug.php\">debugging script</a>";
  57          } else {
  58              echo "Image not found!<br />";
  59              echo "Please try the <a href=\"$CFG->wwwroot/filter/algebra/algebradebug.php\">debugging script</a><br />";
  60              echo "Please turn on debug mode in site configuration to see more info here.";
  61          }
  62      }
  63