threads.h

   1 #pragma once
   2 /*
   3  * This file is part of the libCEC(R) library.
   4  *
   5  * libCEC(R) is Copyright (C) 2011-2013 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(INVALID_THREAD_VALUE) {}
  46
  47     virtual ~CThread(void)
  48     {
  49       StopThread(0);
  50       void *retVal = NULL;
  51       if (m_thread != INVALID_THREAD_VALUE)
  52         if (ThreadsWait(m_thread, &retVal)){}; // silence unused warning
  53     }
  54
  55     static void *ThreadHandler(CThread *thread)
  56     {
  57       void *retVal = NULL;
  58
  59       if (thread)
  60       {
  61         {
  62           CLockObject lock(thread->m_threadMutex);
  63           thread->m_bRunning = true;
  64           thread->m_bStopped = false;
  65           thread->m_threadCondition.Broadcast();
  66         }
  67
  68         retVal = thread->Process();
  69
  70         {
  71           CLockObject lock(thread->m_threadMutex);
  72           thread->m_bRunning = false;
  73           thread->m_bStopped = true;
  74           thread->m_threadCondition.Broadcast();
  75         }
  76       }
  77
  78       return retVal;
  79     }
  80
  81     virtual bool IsRunning(void)
  82     {
  83       CLockObject lock(m_threadMutex);
  84       return m_bRunning;
  85     }
  86
  87     virtual bool IsStopped(void)
  88     {
  89       CLockObject lock(m_threadMutex);
  90       return m_bStop;
  91     }
  92
  93     virtual bool CreateThread(bool bWait = true)
  94     {
  95       bool bReturn(false);
  96       CLockObject lock(m_threadMutex);
  97       if (!IsRunning())
  98       {
  99         m_bStop = false;
 100         if (ThreadsCreate(m_thread, CThread::ThreadHandler, ((void*)static_cast<CThread *>(this))))
 101         {
 102           if (bWait)
 103             m_threadCondition.Wait(m_threadMutex, m_bRunning);
 104           bReturn = true;
 105         }
 106       }
 107       return bReturn;
 108     }
 109
 110     /*!
 111      * @brief Stop the thread
 112      * @param iWaitMs negative = don't wait, 0 = infinite, or the amount of ms to wait
 113      */
 114     virtual bool StopThread(int iWaitMs = 5000)
 115     {
 116       bool bReturn(true);
 117       bool bRunning(false);
 118       {
 119         CLockObject lock(m_threadMutex);
 120         bRunning = IsRunning();
 121         m_bStop = true;
 122       }
 123
 124       if (bRunning && iWaitMs >= 0)
 125       {
 126         CLockObject lock(m_threadMutex);
 127         bReturn = m_threadCondition.Wait(m_threadMutex, m_bStopped, iWaitMs);
 128       }
 129       else
 130       {
 131         bReturn = true;
 132       }
 133
 134       return bReturn;
 135     }
 136
 137     virtual bool Sleep(uint32_t iTimeout)
 138     {
 139       CLockObject lock(m_threadMutex);
 140       return m_bStop ? false : m_threadCondition.Wait(m_threadMutex, m_bStopped, iTimeout);
 141     }
 142
 143     virtual void *Process(void) = 0;
 144
 145   protected:
 146     void SetRunning(bool bSetTo);
 147     CMutex           m_threadMutex;
 148
 149   private:
 150     bool             m_bStop;
 151     bool             m_bRunning;
 152     bool             m_bStopped;
 153     CCondition<bool> m_threadCondition;
 154     thread_t         m_thread;
 155   };
 156 };