mod/quiz/quizfile.php

   1 <?PHP // $Id$
   2       // This function fetches files from the data directory
   3       // Syntax:   quizfile.php/quiz id/question id/dir/.../dir/filename.ext
   4       // It is supposed to be used by the quiz module only
   5       // I believe this is obsolete, everything should be using moodle/file.php GWD
   6
   7     require_once('../../config.php');
   8     require_once($CFG->libdir.'/filelib.php');
   9     require_once('locallib.php');
  10
  11     if (empty($CFG->filelifetime)) {
  12         $lifetime = 86400;     // Seconds for files to remain in caches
  13     } else {
  14         $lifetime = $CFG->filelifetime;
  15     }
  16
  17     // disable moodle specific debug messages
  18     disable_debugging();
  19
  20     $relativepath = get_file_argument('quizfile.php');
  21
  22     if (!$relativepath) {
  23         error('No valid arguments supplied or incorrect server configuration');
  24     }
  25
  26     // extract relative path components
  27     $args = explode('/', trim($relativepath, '/'));
  28     if (count($args) < 3) { // always at least category, question and path
  29         error('No valid arguments supplied');
  30     }
  31
  32     $quizid       = (int)array_shift($args);
  33     $questionid   = (int)array_shift($args);
  34     $relativepath = implode ('/', $args);
  35
  36     if (!($question = get_record('question', 'id', $questionid))) {
  37         error('No valid arguments supplied');
  38     }
  39
  40     if (!($questioncategory = get_record('question_categories', 'id', $question->category))) {
  41         error('No valid arguments supplied');
  42     }
  43
  44     /////////////////////////////////////
  45     // Check access
  46     /////////////////////////////////////
  47     if ($quizid == 0) { // teacher doing preview during quiz creation
  48         if ($questioncategory->publish) {
  49             require_login();
  50             if (!isteacherinanycourse()) {
  51               error('No valid arguments supplied');
  52             }
  53         } else {
  54             require_login($questioncategory->course);
  55             $cm = get_coursemodule_from_instance('quiz', $quizid);
  56             require_capability('mod/quiz:preview', get_context_instance(CONTEXT_MODULE, $cm->id));
  57         }
  58     } else {
  59         if (!($quiz = get_record('quiz', 'id', $quizid))) {
  60             error('No valid arguments supplied');
  61         }
  62         if (!($course = get_record('course', 'id', $quiz->course))) {
  63             error('No valid arguments supplied');
  64         }
  65         require_login($course->id);
  66
  67         // For now, let's not worry about this.  The following check causes
  68         // problems sometimes when reviewing a quiz
  69         //if (!isteacher($course->id)
  70         //    and !quiz_get_user_attempt_unfinished($quiz->id, $USER->id)
  71         //    and ! ($quiz->review  &&  time() > $quiz->timeclose)
  72         //        || !quiz_get_user_attempts($quiz->id, $USER->id) )
  73         //{
  74         //    error("Logged-in user is not allowed to view this quiz");
  75         //}
  76
  77         ///////////////////////////////////////////////////
  78         // The logged-in user has the right to view material on this quiz!
  79         // Now verify the consistency between $quiz, $question, its category and $relativepathname
  80         ///////////////////////////////////////////////////
  81
  82         // For now, let's not worry about this.  The following check doesn't
  83         // work for randomly selected questions and it gets complicated
  84         //if (!in_array($question->id, explode(',', $quiz->questions), FALSE)) {
  85         //    error("Specified question is not on the specified quiz");
  86         //}
  87     }
  88
  89     // Have the question check whether it uses this file or not
  90     if (!$QTYPES[$question->qtype]->uses_quizfile($question,
  91                                                        $relativepath)) {
  92         error("The specified file path is not on the specified question");
  93     }
  94
  95
  96     ///////////////////////////////////////////
  97     // All security stuff is now taken care of.
  98     // Specified file can now be returned...
  99     //////////////////////////////////////////
 100
 101     $pathname = "$CFG->dataroot/$questioncategory->course/$relativepath";
 102     $filename = $args[count($args)-1];
 103
 104
 105     if (file_exists($pathname)) {
 106         send_file($pathname, $filename, $lifetime);
 107     } else {
 108         header('HTTP/1.0 404 not found');
 109         error(get_string('filenotfound', 'error')); //this is not displayed on IIS??
 110     }
 111 ?>