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         m_thread(NULL) {}
  46
  47     virtual ~CThread(void)
  48     {
  49       StopThread(0);
  50       void *retVal;
  51       if (m_thread)
  52         ThreadsWait(m_thread, &retVal);
  53       #if defined(__WINDOWS__)
  54       (void *)retVal; //"unreferenced local variable" warning
  55       #endif
  56     }
  57
  58     static void *ThreadHandler(CThread *thread)
  59     {
  60       void *retVal = NULL;
  61
  62       if (thread)
  63       {
  64         {
  65           CLockObject lock(thread->m_threadMutex);
  66           thread->m_bRunning = true;
  67           thread->m_bStopped = false;
  68           thread->m_threadCondition.Broadcast();
  69         }
  70
  71         retVal = thread->Process();
  72
  73         {
  74           CLockObject lock(thread->m_threadMutex);
  75           thread->m_bRunning = false;
  76           thread->m_bStopped = true;
  77           thread->m_threadCondition.Broadcast();
  78         }
  79       }
  80
  81       return retVal;
  82     }
  83
  84     virtual bool IsRunning(void)
  85     {
  86       CLockObject lock(m_threadMutex);
  87       return m_bRunning;
  88     }
  89
  90     virtual bool IsStopped(void)
  91     {
  92       CLockObject lock(m_threadMutex);
  93       return m_bStop;
  94     }
  95
  96     virtual bool CreateThread(bool bWait = true)
  97     {
  98       bool bReturn(false);
  99       CLockObject lock(m_threadMutex);
 100       if (!IsRunning())
 101       {
 102         m_bStop = false;
 103         if (ThreadsCreate(m_thread, CThread::ThreadHandler, ((void*)static_cast<CThread *>(this))))
 104         {
 105           if (bWait)
 106             m_threadCondition.Wait(m_threadMutex, m_bRunning);
 107           bReturn = true;
 108         }
 109       }
 110       return bReturn;
 111     }
 112
 113     /*!
 114      * @brief Stop the thread
 115      * @param iWaitMs negative = don't wait, 0 = infinite, or the amount of ms to wait
 116      */
 117     virtual bool StopThread(int iWaitMs = 5000)
 118     {
 119       bool bReturn(true);
 120       bool bRunning(false);
 121       {
 122         CLockObject lock(m_threadMutex);
 123         bRunning = IsRunning();
 124         m_bStop = true;
 125       }
 126
 127       if (bRunning && iWaitMs >= 0)
 128       {
 129         CLockObject lock(m_threadMutex);
 130         bReturn = m_threadCondition.Wait(m_threadMutex, m_bStopped, iWaitMs);
 131       }
 132       else
 133       {
 134         bReturn = true;
 135       }
 136
 137       return bReturn;
 138     }
 139
 140     virtual bool Sleep(uint32_t iTimeout)
 141     {
 142       CLockObject lock(m_threadMutex);
 143       return m_bStop ? false : m_threadCondition.Wait(m_threadMutex, m_bStopped, iTimeout);
 144     }
 145
 146     virtual void *Process(void) = 0;
 147
 148   protected:
 149     void SetRunning(bool bSetTo);
 150     CMutex           m_threadMutex;
 151
 152   private:
 153     bool             m_bStop;
 154     bool             m_bRunning;
 155     bool             m_bStopped;
 156     CCondition<bool> m_threadCondition;
 157     thread_t         m_thread;
 158   };
 159 };