win32 synch objects.js

/*
  Shows that Mutexes, Events, and Critical Sections are available in js "threading" model too. :)

  WaitForSingleObject http://msdn.microsoft.com/en-us/library/ms687032(VS.85).aspx
  WaitForMultipleObjects http://msdn.microsoft.com/en-us/library/ms687025(VS.85).aspx
  Event http://msdn.microsoft.com/en-us/library/ms682396(VS.85).aspx
*/

(function($G)
{
  var Event = function(state)
  {
    if(state != null)
    {
      this.state = Boolean(state);
    }
    else
    {
      this.state = false;
    }

    this.onSetFns = [];
  };
  
  Event.prototype._set = function(state)
  {
    if(this.state != state)
    {
      this.state = state;

      var i = this.onSetFns.length; while(i--)
        this.onSetFns[i](this);
    }
  };
  
  Event.prototype._attachListener = function(_fn)
  {
    if(this.onSetFns.indexOf(_fn) < 0)
      this.onSetFns.push(_fn);
  };
  
  Event.prototype._detachListener = function(_fn)
  {
    var i = this.onSetFns.indexOf(_fn);
    
    if(i > -1)
      this.onSetFns.splice(i, 1);
  };
  
  var _waitForSingleObject = function(m, timeout, _fn)
  {
    var _final = function()
    {
      m._detachListener(_onSet)
      _fn();
    };
    
    var _onSet = function(m)
    {
      if(m.state)
        _final();
    };
    
    if(m.state)
    {
      _fn();
    }
    else
    {
      m._attachListener(_onSet);
    
      if(timeout > 0 && timeout < +Infinity)
      {
        setTimeout(
          _final,
          timeout
        );
      }
    }  
  };

  var _waitForMultipleObject = function(ms, timeout, _fn)
  {
    var _final = function()
    {
      var i = ms.length; while(i--)
        ms[i]._detachListener(_onSet);
      
      _fn();
    };
    
    var _onSet = function(m)
    {
      if(m.state)
      {
        --n;

        if(n == 0)
          _final();
      }
      else
      {
        ++n;
      }
    };
    
    var n = 0;
    var i = ms.length; while(i--)
    {  
      if(!ms[i].state)
        ++n;
    }
    
    if(n == 0)
    {  
      _fn();
    }
    else
    {
      var i = ms.length; while(i--)
        ms[i]._attachListener(_onSet);

      if(timeout > 0 && timeout < +Infinity)
      {
        setTimeout(
          _final,
          timeout
        );
      }
    }
  };
  
  var _sleep = function(time, _fn)
  {
    setTimeout(_fn, time);
  };

  (function()
  {
    var img = new Image();
    var m = new Event(false);
    
    img.onload = function()
    {
      console.log('img.onload');
      _sleep(1000, function()
      {
        m._set(true);
      });
    };
    
    img.src = 'data:image/gif;base64,R0lGODlhAgACAIAAAAAAAP///yH5BAkAAAEALAAAAAACAAIAAAIDDBIFADs=';
    
    _waitForSingleObject(m, +Infinity, function()
    {
      console.log('m');
    });
    
  })();

  (function()
  {
    var img1 = new Image();
    var img2 = new Image();
    var m1 = new Event(false);
    var m2 = new Event(false);
    
    img1.onload = function()
    {
      console.log('img1.onload');
      m1._set(true);
    };
    img2.onload = function()
    {
      console.log('img2.onload');
      _sleep(1000, function()
      {
        m2._set(true);
      });
    };
    
    img1.src = 'data:image/gif;base64,R0lGODlhAgACAIAAAAAAAP///yH5BAkAAAEALAAAAAACAAIAAAIDDBIFADs=';
    img2.src = 'data:image/gif;base64,R0lGODlhAgACAIAAAAAAAP///yH5BAkAAAEALAAAAAACAAIAAAIDDBIFADs=';
    
    _waitForMultipleObject([m1, m2], +Infinity, function()
    {
      console.log('m1, m2');
    });
    
  })();
  
})(this);