// This file is part of iSnooze.
//
// iSnooze is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// iSnooze 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 General Public License
// along with iSnooze; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#ifndef LimitSingleInstance_H
#define LimitSingleInstance_H

#include <windows.h> 

//this code is from Q243953 in case you lose the article and wonder
//where this code came from...
class CLimitSingleInstance
{
protected:
  DWORD  m_dwLastError;
  HANDLE m_hMutex;

public:
  CLimitSingleInstance(TCHAR *strMutexName)
  {
    //be sure to use a name that is unique for this application otherwise
    //two apps may think they are the same if they are using same name for
    //3rd parm to CreateMutex
    m_hMutex = CreateMutex(NULL, FALSE, strMutexName); //do early
    m_dwLastError = GetLastError(); //save for use later...
  }
   
  ~CLimitSingleInstance() 
  {
    if (m_hMutex)  //don't forget to close handles...
    {
       CloseHandle(m_hMutex); //do as late as possible
       m_hMutex = NULL; //good habit to be in
    }
  }

  BOOL IsAnotherInstanceRunning() 
  {
    return (ERROR_ALREADY_EXISTS == m_dwLastError);
  }
};
#endif