chrome/test/data/media/html/utils.js

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 //
   5 // Miscellaneous utility functions for HTML media tests. Loading this script
   6 // should not modify the page in any way.
   7 //
   8
   9 var QueryString = function () {
  10   // Allows access to query parameters on the URL; e.g., given a URL like:
  11   //
  12   //    http://<url>/my.html?test=123&bob=123
  13   //
  14   // parameters can now be accessed via QueryString.test or QueryString.bob.
  15   var params = {};
  16
  17   // RegEx to split out values by &.
  18   var r = /([^&=]+)=?([^&]*)/g;
  19
  20   // Lambda function for decoding extracted match values. Replaces '+' with
  21   // space so decodeURIComponent functions properly.
  22   function d(s) { return decodeURIComponent(s.replace(/\+/g, ' ')); }
  23
  24   var match;
  25   while (match = r.exec(window.location.search.substring(1)))
  26     params[d(match[1])] = d(match[2]);
  27
  28   return params;
  29 } ();
  30
  31 function getCurrentTime() {
  32   if (window.performance.now)
  33     return window.performance.now();
  34   else
  35     return new Date().getTime();
  36 }
  37
  38 function Timer() {
  39   this.start_ = 0;
  40   this.times_ = [];
  41 }
  42
  43 Timer.prototype = {
  44   start: function() {
  45     this.start_ = getCurrentTime();
  46   },
  47
  48   stop: function() {
  49     var delta = getCurrentTime() - this.start_;
  50     this.times_.push(delta);
  51     return delta;
  52   },
  53
  54   reset: function() {
  55     this.start_ = 0;
  56     this.times_ = [];
  57   }
  58 }
  59
  60 function GenerateUniqueURL(src) {
  61   var ch = src.indexOf('?') >= 0 ? '&' : '?';
  62   return src + ch + 't=' + (new Date()).getTime();
  63 }