text: //
  //  boost/signals2/detail/lwm_win32_cs.hpp
  //
  //  Copyright (c) 2002, 2003 Peter Dimov
  //  Copyright (c) 2008 Frank Mori Hess
  //
  // Distributed under the Boost Software License, Version 1.0. (See
  // accompanying file LICENSE_1_0.txt or copy at
  // http://www.boost.org/LICENSE_1_0.txt)
  //
  
  #ifndef BOOST_SIGNALS2_LWM_WIN32_CS_HPP
  #define BOOST_SIGNALS2_LWM_WIN32_CS_HPP
  
  // MS compatible compilers support #pragma once
  
  #if defined(_MSC_VER) && (_MSC_VER >= 1020)
  # pragma once
  #endif
  
  #include <boost/assert.hpp>
  
  #ifdef BOOST_USE_WINDOWS_H
  #  include <windows.h>
  #endif
  
  namespace boost
  {
  
  namespace signals2
  {
  
  #ifndef BOOST_USE_WINDOWS_H
  
  struct critical_section
  {
      struct critical_section_debug * DebugInfo;
      long LockCount;
      long RecursionCount;
      void * OwningThread;
      void * LockSemaphore;
  #if defined(_WIN64)
      unsigned __int64 SpinCount;
  #else
      unsigned long SpinCount;
  #endif
  };
  
  extern "C" __declspec(dllimport) void __stdcall InitializeCriticalSection(critical_section *);
  extern "C" __declspec(dllimport) void __stdcall EnterCriticalSection(critical_section *);
  extern "C" __declspec(dllimport) bool __stdcall TryEnterCriticalSection(critical_section *);
  extern "C" __declspec(dllimport) void __stdcall LeaveCriticalSection(critical_section *);
  extern "C" __declspec(dllimport) void __stdcall DeleteCriticalSection(critical_section *);
  
  #else
  
  typedef ::CRITICAL_SECTION critical_section;
  
  #endif // #ifndef BOOST_USE_WINDOWS_H
  
  class mutex
  {
  private:
  
      critical_section cs_;
  
      mutex(mutex const &);
      mutex & operator=(mutex const &);
  
  public:
  
      mutex()
      {
          InitializeCriticalSection(&cs_);
      }
  
      ~mutex()
      {
          DeleteCriticalSection(&cs_);
      }
  
      void lock()
      {
          EnterCriticalSection(&cs_);
      }
  // TryEnterCriticalSection only exists on Windows NT 4.0 and later
  #if (defined(_WIN32_WINNT) && (_WIN32_WINNT >= 0x0400))
      bool try_lock()
      {
          return TryEnterCriticalSection(&cs_) != 0;
      }
  #else
      bool try_lock()
      {
          BOOST_ASSERT(false);
          return false;
      }
  #endif
      void unlock()
      {
          LeaveCriticalSection(&cs_);
      }
  };
  
  } // namespace signals2
  
  } // namespace boost
  
  #endif // #ifndef BOOST_SIGNALS2_LWM_WIN32_CS_HPP
  