src/AsyncFramework/Thread.h

   1 /***************************************************************************
   2  *   Copyright (C) 2009 by Stefan Fuhrmann                                 *
   3  *   stefanfuhrmann@alice-dsl.de                                           *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  19  ***************************************************************************/
  20
  21 #pragma once
  22
  23 #include "WaitableEvent.h"
  24
  25 /**
  26 * Repeatedly executes a function until \ref Terminate
  27 * is called. The function should not be long-running.
  28 * If the function returns \a true, the thread will terminate
  29 * automatically and delete the CThread instance.
  30 *
  31 * \ref Suspend and \ref Resume will not wait until the
  32 * thread actually enters the respective state.
  33 * \ref Terminate, however, will only return when \ref func
  34 * has exited and will not be called again.
  35 *
  36 * Please note that this class is designed to be controlled
  37 * by _one_ outer thread. Trying to control it from multiple
  38 * threads may result in unstable behavior.
  39 */
  40
  41 namespace async
  42 {
  43
  44 class CThread
  45 {
  46 private:
  47
  48     /// the thread handle
  49
  50     uintptr_t thread;
  51
  52     /// if set, the thread function should exit asap
  53
  54     volatile bool terminated;
  55
  56     /// set, if the thread function has terminated
  57
  58     CWaitableEvent done;
  59
  60     /// allow for the thread to become inactive
  61
  62     volatile bool suspended;
  63     CWaitableEvent suspend;
  64     CWaitableEvent resume;
  65
  66     /// to be executed cyclicly
  67
  68     bool (*func)(void *);
  69     void* args;
  70
  71     /// the actual thread function
  72
  73     static void ThreadFunc (void*);
  74
  75 public:
  76
  77     /// auto-start thread during construction
  78
  79     CThread (bool (*func)(void *), void* args, bool startSuspended = false);
  80     ~CThread(void);
  81
  82     /// thread control
  83
  84     void Suspend();
  85     void Resume();
  86     void Terminate();
  87 };
  88
  89 }