src/lib/platform/threads/threads.h

   1 #pragma once
   2 /*
   3  * This file is part of the libCEC(R) library.
   4  *
   5  * libCEC(R) is Copyright (C) 2011-2012 Pulse-Eight Limited.  All rights reserved.
   6  * libCEC(R) is an original work, containing original code.
   7  *
   8  * libCEC(R) is a trademark of Pulse-Eight Limited.
   9  *
  10  * This program is dual-licensed; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  *
  24  *
  25  * Alternatively, you can license this library under a commercial license,
  26  * please contact Pulse-Eight Licensing for more information.
  27  *
  28  * For more information contact:
  29  * Pulse-Eight Licensing       <license@pulse-eight.com>
  30  *     http://www.pulse-eight.com/
  31  *     http://www.pulse-eight.net/
  32  */
  33
  34 #include "mutex.h"
  35
  36 namespace PLATFORM
  37 {
  38   class CThread
  39   {
  40   public:
  41     CThread(void) :
  42         m_bStop(false),
  43         m_bRunning(false),
  44         m_bStopped(false) {}
  45
  46     virtual ~CThread(void)
  47     {
  48       StopThread(0);
  49       void *retVal;
  50       ThreadsWait(m_thread, &retVal);
  51       (void *)retVal; //"unreferenced local variable" warning
  52     }
  53
  54     static void *ThreadHandler(CThread *thread)
  55     {
  56       void *retVal = NULL;
  57
  58       if (thread)
  59       {
  60         {
  61           CLockObject lock(thread->m_threadMutex);
  62           thread->m_bRunning = true;
  63           thread->m_bStopped = false;
  64           thread->m_threadCondition.Broadcast();
  65         }
  66
  67         retVal = thread->Process();
  68
  69         {
  70           CLockObject lock(thread->m_threadMutex);
  71           thread->m_bRunning = false;
  72           thread->m_bStopped = true;
  73           thread->m_threadCondition.Broadcast();
  74         }
  75       }
  76
  77       return retVal;
  78     }
  79
  80     virtual bool IsRunning(void)
  81     {
  82       CLockObject lock(m_threadMutex);
  83       return m_bRunning;
  84     }
  85
  86     virtual bool IsStopped(void)
  87     {
  88       CLockObject lock(m_threadMutex);
  89       return m_bStop;
  90     }
  91
  92     virtual bool CreateThread(bool bWait = true)
  93     {
  94         bool bReturn(false);
  95         CLockObject lock(m_threadMutex);
  96         if (!IsRunning())
  97         {
  98           m_bStop = false;
  99           if (ThreadsCreate(m_thread, CThread::ThreadHandler, ((void*)static_cast<CThread *>(this))))
 100           {
 101             if (bWait)
 102               m_threadCondition.Wait(m_threadMutex, m_bRunning);
 103             bReturn = true;
 104           }
 105         }
 106       return bReturn;
 107     }
 108
 109     /*!
 110      * @brief Stop the thread
 111      * @param iWaitMs negative = don't wait, 0 = infinite, or the amount of ms to wait
 112      */
 113     virtual bool StopThread(int iWaitMs = 5000)
 114     {
 115       bool bReturn(true);
 116       bool bRunning(false);
 117       {
 118         CLockObject lock(m_threadMutex);
 119         bRunning = IsRunning();
 120         m_bStop = true;
 121       }
 122
 123       if (bRunning && iWaitMs >= 0)
 124       {
 125         CLockObject lock(m_threadMutex);
 126         bReturn = m_threadCondition.Wait(m_threadMutex, m_bStopped, iWaitMs);
 127       }
 128       else
 129       {
 130         bReturn = true;
 131       }
 132
 133       return bReturn;
 134     }
 135
 136     virtual bool Sleep(uint32_t iTimeout)
 137     {
 138       CLockObject lock(m_threadMutex);
 139       return m_bStop ? false : m_threadCondition.Wait(m_threadMutex, m_bStopped, iTimeout);
 140     }
 141
 142     virtual void *Process(void) = 0;
 143
 144   protected:
 145     void SetRunning(bool bSetTo);
 146
 147   private:
 148     bool             m_bStop;
 149     bool             m_bRunning;
 150     bool             m_bStopped;
 151     CCondition<bool> m_threadCondition;
 152     CMutex           m_threadMutex;
 153     thread_t         m_thread;
 154   };
 155 };