Use the event-handler for timers.

src/vm/event_handler.h

 // Copyright (c) 2015, the Fletch project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE.md file.
 
 #ifndef SRC_VM_EVENT_HANDLER_H_
 #define SRC_VM_EVENT_HANDLER_H_
 
 #include "src/shared/globals.h"
+#include "src/vm/hash_map.h"
 #include "src/vm/thread.h"
 
 namespace fletch {
 
 class Monitor;
 class Port;
 
 class EventHandler {
  public:
   enum {
     READ_EVENT        = 1 << 0,
     WRITE_EVENT       = 1 << 1,
     CLOSE_EVENT       = 1 << 2,
     ERROR_EVENT       = 1 << 3,
   };
 
   EventHandler();
   ~EventHandler();
 
   int GetEventHandler();
 
+  void ScheduleTimeout(int64 timeout, Port* port);
+
   Monitor* monitor() const { return monitor_; }
 
   int Create();
   void Run();
 
  private:
   Monitor* monitor_;
   int fd_;
   ThreadIdentifier thread_;
 
+  HashMap<Port*, int64> timeouts_;
+  int64 next_timeout_;
+
   int read_fd_;
   int write_fd_;
 
+  void HandleTimeouts();
+
   void Send(Port* port, uword mask);
 };
 
 }  // namespace fletch
 
 #endif  // SRC_VM_EVENT_HANDLER_H_