common/JackActivationCount.h

   1 /*
   2 Copyright (C) 2004-2008 Grame
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU Lesser General Public License as published by
   6 the Free Software Foundation; either version 2.1 of the License, or
   7 (at your option) any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU Lesser General Public License for more details.
  13
  14 You should have received a copy of the GNU Lesser General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17
  18 */
  19
  20 #ifndef __JackActivationCount__
  21 #define __JackActivationCount__
  22
  23 #include "JackPlatformPlug.h"
  24 #include "JackTime.h"
  25 #include "JackTypes.h"
  26
  27 namespace Jack
  28 {
  29
  30 struct JackClientControl;
  31
  32 /*!
  33 \brief Client activation counter.
  34 */
  35
  36 PRE_PACKED_STRUCTURE
  37 class JackActivationCount
  38 {
  39
  40     private:
  41
  42         alignas(SInt32) SInt32 fValue;
  43         SInt32 fCount;
  44
  45     public:
  46
  47         JackActivationCount(): fValue(0), fCount(0)
  48         {
  49             static_assert(offsetof(JackActivationCount, fValue) % sizeof(fValue) == 0,
  50                           "fValue must be aligned within JackActivationCount");
  51         }
  52
  53         bool Signal(JackSynchro* synchro, JackClientControl* control);
  54
  55         inline void Reset()
  56         {
  57             fValue = fCount;
  58         }
  59
  60         inline void SetValue(int val)
  61         {
  62             fCount = val;
  63         }
  64
  65         inline void IncValue()
  66         {
  67             fCount++;
  68         }
  69
  70         inline void DecValue()
  71         {
  72             fCount--;
  73         }
  74
  75         inline int GetValue() const
  76         {
  77             return fValue;
  78         }
  79
  80 }  POST_PACKED_STRUCTURE;
  81
  82 } // end of namespace
  83
  84
  85 #endif