text: /***************************************************************************
   *   Copyright (C) 2008 by Dominik Seichter                                *
   *   domseichter@web.de                                                    *
   *                                                                         *
   *   This program is free software; you can redistribute it and/or modify  *
   *   it under the terms of the GNU Library General Public License as       *
   *   published by the Free Software Foundation; either version 2 of the    *
   *   License, or (at your option) any later version.                       *
   *                                                                         *
   *   This program is distributed in the hope that it will be useful,       *
   *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
   *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
   *   GNU General Public License for more details.                          *
   *                                                                         *
   *   You should have received a copy of the GNU Library General Public     *
   *   License along with this program; if not, write to the                 *
   *   Free Software Foundation, Inc.,                                       *
   *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
   *                                                                         *
   *   In addition, as a special exception, the copyright holders give       *
   *   permission to link the code of portions of this program with the      *
   *   OpenSSL library under certain conditions as described in each         *
   *   individual source file, and distribute linked combinations            *
   *   including the two.                                                    *
   *   You must obey the GNU General Public License in all respects          *
   *   for all of the code used other than OpenSSL.  If you modify           *
   *   file(s) with this exception, you may extend this exception to your    *
   *   version of the file(s), but you are not obligated to do so.  If you   *
   *   do not wish to do so, delete this exception statement from your       *
   *   version.  If you delete this exception statement from all source      *
   *   files in the program, then also delete it here.                       *
   ***************************************************************************/
  
  #include "../PdfDefines.h"
  #include "../PdfDefinesPrivate.h"
  
  #if ! defined(PODOFO_MULTI_THREAD)
  #error "Not a multi-thread build. PdfMutex_null.h should be used instead"
  #endif
  
  #if !defined(_WIN32)
  #error "Wrong PdfMutex implementation included!"
  #endif
  
  namespace PoDoFo {
  namespace Util {
  
  /** 
   * A platform independent reentrant mutex, win32 implementation.
   */
  class PdfMutexImpl {
    public:
      /** Construct a new mutex
       */
      inline PdfMutexImpl();
  
      inline ~PdfMutexImpl();
  
      /**
       * Lock the mutex
       */
      inline void Lock();
  
      /**
       * Try locking the mutex. 
       *
       * \returns true if the mutex was locked
       * \returns false if the mutex is already locked
       *                by some other thread
       */
      inline bool TryLock();
  
      /**
       * Unlock the mutex
       */
      inline void UnLock();
  
    private:
      CRITICAL_SECTION m_cs;
  };
  
  PdfMutexImpl::PdfMutexImpl()
  {
  	// Visual Studio Code Analyzer warns that InitializeCriticalSection must be within try/catch block
  	// because InitializeCriticalSection can raise a STATUS_NO_MEMORY exception in low memory conditions
  	// on Windows XP / Server 2003. The exception was eliminated in Windows Vista / Server 2008,
  	// so don't warn if building for Vista or later.
  
  #if ( WINVER >= _WIN32_WINNT_VISTA )
  	#pragma warning(disable : 28125)
  #endif
  
      InitializeCriticalSection( &m_cs );
  
  #if ( WINVER >= _WIN32_WINNT_VISTA )
  	#pragma warning(default : 28125)
  #endif
  
  }
  
  PdfMutexImpl::~PdfMutexImpl()
  {
      DeleteCriticalSection( &m_cs );
  }
  
  void PdfMutexImpl::Lock()
  {
      EnterCriticalSection( &m_cs );
  }
  
  bool PdfMutexImpl::TryLock()
  {
      return (TryEnterCriticalSection( &m_cs ) ? true : false);
  }
  
  void PdfMutexImpl::UnLock()
  {
      LeaveCriticalSection( &m_cs );
  }
  
  
  }; // Util
  }; // PoDoFo
  