xbmc/utils/SingleLock.cpp

   1 /*
   2  * XBMC Media Center
   3  * Copyright (c) 2002 Frodo
   4  * Portions Copyright (c) by the authors of ffmpeg and xvid
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include "SingleLock.h"
  22
  23
  24 //////////////////////////////////////////////////////////////////////
  25 // Construction/Destruction
  26 //////////////////////////////////////////////////////////////////////
  27
  28 CSingleLock::CSingleLock(CCriticalSection& cs)
  29     : m_cs( cs )
  30     , m_bIsOwner( false )
  31 {
  32   Enter();
  33 }
  34
  35 CSingleLock::CSingleLock(const CCriticalSection& cs)
  36     : m_cs( const_cast<CCriticalSection&>(cs) )
  37     , m_bIsOwner( false )
  38 {
  39   Enter();
  40 }
  41
  42 CSingleLock::~CSingleLock()
  43 {
  44   Leave();
  45 }
  46
  47 bool CSingleLock::IsOwner() const
  48 {
  49   return m_bIsOwner;
  50 }
  51
  52 bool CSingleLock::Enter()
  53 {
  54   // Test if we already own the critical section
  55   if ( true == m_bIsOwner )
  56   {
  57     return true;
  58   }
  59
  60   // Blocking call
  61   ::EnterCriticalSection( m_cs );
  62   m_bIsOwner = true;
  63
  64   return m_bIsOwner;
  65 }
  66
  67 void CSingleLock::Leave()
  68 {
  69   if ( false == m_bIsOwner )
  70   {
  71     return ;
  72   }
  73
  74   ::LeaveCriticalSection( m_cs );
  75   m_bIsOwner = false;
  76 }
  77
  78 CSingleExit::CSingleExit(CCriticalSection& cs)
  79     : m_cs( cs )
  80     , m_count(0)
  81 {
  82   Exit();
  83 }
  84
  85  CSingleExit::CSingleExit(const CCriticalSection& cs)
  86     : m_cs(const_cast<CCriticalSection&>(cs))
  87     , m_count(0)
  88 {
  89   Exit();
  90 }
  91
  92 CSingleExit::~CSingleExit()
  93 {
  94   Restore();
  95 }
  96
  97 void CSingleExit::Exit()
  98 {
  99   if(m_count == 0)
 100     m_count = ::ExitCriticalSection(m_cs);
 101 }
 102
 103 void CSingleExit::Restore()
 104 {
 105   if(m_count)
 106   {
 107     RestoreCriticalSection(m_cs, m_count);
 108     m_count = 0;
 109   }
 110 }
 111
 112