Separating scheduler into bunch of files
diff --git a/scheduler/task.h b/scheduler/task.h
new file mode 100644
index 0000000..8289c57
--- /dev/null
+++ b/scheduler/task.h
@@ -0,0 +1,99 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ *         Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef TASK_H
+#define TASK_H
+
+#define _OVERRIDE
+#ifdef __GNUC__
+#if __GNUC_MAJOR >= 4 && __GNUC_MINOR__ >= 7
+  #undef _OVERRIDE
+  #define _OVERRIDE override
+#endif // __GNUC__ version
+#endif // __GNUC__
+
+#include <boost/function.hpp>
+#include <boost/shared_ptr.hpp>
+#include <sys/time.h>
+
+//////////////////////////////////////////////////
+// forward declarations
+class Task;
+typedef boost::shared_ptr<Task> TaskPtr;
+
+class Scheduler;
+typedef boost::shared_ptr<Scheduler> SchedulerPtr;
+
+struct event;
+//////////////////////////////////////////////////
+
+
+/**
+ * @brief Base class for a task
+ */
+class Task
+{
+public:
+  // callback of this task
+  typedef boost::function<void ()> Callback;
+  // tag identifies this task, should be unique
+  typedef std::string Tag;
+  // used to match tasks
+  typedef boost::function<bool (const TaskPtr &task)> TaskMatcher;
+
+  // Task is associated with Schedulers due to the requirement that libevent event is associated with an libevent event_base
+  Task(const Callback &callback, const Tag &tag, const SchedulerPtr &scheduler);
+  virtual ~Task();
+
+  virtual void
+  run() = 0;
+
+  Tag
+  tag() { return m_tag; }
+
+  event *
+  ev() { return m_event; }
+
+  timeval *
+  tv() { return m_tv; }
+
+  // Task needs to be resetted after the callback is invoked if it is to be schedule again; just for safety
+  // it's called by scheduler automatically when addTask or rescheduleTask is called;
+  // Tasks should do preparation work here (e.g. set up new delay, etc. )
+  virtual void
+  reset() = 0;
+
+  // set delay
+  // This overrides whatever delay kept in m_tv
+  void
+  setTv(double delay);
+
+protected:
+  Callback m_callback;
+  Tag m_tag;
+  SchedulerPtr m_scheduler;
+  bool m_invoked;
+  event *m_event;
+  timeval *m_tv;
+};
+
+
+#endif // TASK_H