Separating scheduler into bunch of files
diff --git a/scheduler/scheduler.h b/scheduler/scheduler.h
new file mode 100644
index 0000000..f6f1fe8
--- /dev/null
+++ b/scheduler/scheduler.h
@@ -0,0 +1,113 @@
+/* -*- 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 SCHEDULER_H
+#define SCHEDULER_H
+
+#include <event2/event.h>
+#include <event2/thread.h>
+#include <event2/event-config.h>
+#include <event2/util.h>
+
+#include <boost/function.hpp>
+#include <boost/shared_ptr.hpp>
+
+#include <boost/exception/all.hpp>
+#include <boost/thread/shared_mutex.hpp>
+#include <boost/thread/thread.hpp>
+#include <math.h>
+#include <map>
+#include <sys/time.h>
+
+#include "task.h"
+
+/**
+ * @brief Scheduler class
+ */
+class Scheduler
+{
+public:
+  Scheduler();
+  virtual ~Scheduler();
+
+  // start event scheduling
+  virtual void
+  start();
+
+  // stop event scheduling
+  virtual void
+  shutdown();
+
+  // if task with the same tag exists, the task is not added and return false
+  virtual bool
+  addTask(const TaskPtr &task);
+
+  // delete task by tag, regardless of whether it's invoked or not
+  // if no task is found, no effect
+  virtual void
+  deleteTask(const Task::Tag &tag);
+
+  // delete tasks by matcher, regardless of whether it's invoked or not
+  // this is flexiable in that you can use any form of criteria in finding tasks to delete
+  // but keep in mind this is a linear scan
+
+  // if no task is found, no effect
+  virtual void
+  deleteTask(const Task::TaskMatcher &matcher);
+
+  // task must already have been added to the scheduler, otherwise this method has no effect
+  // this is usually used by PeriodicTask
+  virtual void
+  rescheduleTask(const Task::Tag &tag);
+
+  void
+  eventLoop();
+
+  event_base *
+  base() { return m_base; }
+
+  // used in test
+  int
+  size();
+
+protected:
+  bool
+  addToMap(const TaskPtr &task);
+
+protected:
+  typedef std::map<Task::Tag, TaskPtr> TaskMap;
+  typedef std::map<Task::Tag, TaskPtr>::iterator TaskMapIt;
+  typedef boost::shared_mutex Mutex;
+  typedef boost::unique_lock<Mutex> WriteLock;
+  typedef boost::shared_lock<Mutex> ReadLock;
+  TaskMap m_taskMap;
+  Mutex m_mutex;
+  bool m_running;
+  event_base *m_base;
+  boost::thread m_thread;
+};
+
+class Scheduler;
+typedef boost::shared_ptr<Scheduler> SchedulerPtr;
+
+struct SchedulerException : virtual boost::exception, virtual std::exception { };
+
+#endif // SCHEDULER_H