1 files changed, 72 insertions, 0 deletions
diff --git a/storage/ndb/src/kernel/blocks/qmgr/timer.hpp b/storage/ndb/src/kernel/blocks/qmgr/timer.hpp
new file mode 100644
index 00000000000..9c35a23766c
--- /dev/null
+++ b/storage/ndb/src/kernel/blocks/qmgr/timer.hpp
@@ -0,0 +1,72 @@
+/* Copyright (C) 2003 MySQL AB
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   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 */
+
+/**
+ *  @class Timer
+ *  @brief A timer class that can't be fooled by NTP:ing the system clock to old time
+ */
+class Timer {
+public:
+  Timer() {
+    m_delay = 10;
+  };
+
+  Timer(NDB_TICKS delay_time) {
+    m_delay = delay_time;
+  }
+
+  /**
+   *  Set/Get alarm time of timer
+   */
+  inline void       setDelay(NDB_TICKS delay_time) { m_delay = delay_time;  }
+  inline NDB_TICKS  getDelay()                     { return m_delay; }
+
+  /**
+   *  Start timer
+   */
+  inline void reset() { 
+    m_current_time = NdbTick_CurrentMillisecond();
+    m_alarm_time = m_current_time + m_delay;
+  }
+  
+  /**
+   *  Check for alarm
+   */ 
+  inline bool check() { return check(NdbTick_CurrentMillisecond()); }
+
+  inline bool check(NDB_TICKS check_time) {
+    /**
+     *  Standard alarm check
+     */
+    if (check_time > m_alarm_time) return true;
+
+    /**
+     *  Time progressing, but it is not alarm time yet
+     */
+    if (check_time >= m_current_time) return false;
+
+    /**
+     *  Time has moved backwards
+     */
+    reset();
+    return false;
+  }    
+
+private:
+  NDB_TICKS m_current_time;
+  NDB_TICKS m_alarm_time;
+  NDB_TICKS m_delay;
+};