//////////////////////////////////////////////////////////////////////////////
 //
 // (C) Copyright Ion Gaztanaga 2011-2012. 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)
 //
 // See http://www.boost.org/libs/interprocess for documentation.
 //
 //////////////////////////////////////////////////////////////////////////////
 
 #ifndef BOOST_INTERPROCESS_DETAIL_WINAPI_SEMAPHORE_WRAPPER_HPP
 #define BOOST_INTERPROCESS_DETAIL_WINAPI_SEMAPHORE_WRAPPER_HPP
 
 #ifndef BOOST_CONFIG_HPP
 #  include <boost/config.hpp>
 #endif
 #
 #if defined(BOOST_HAS_PRAGMA_ONCE)
 #  pragma once
 #endif
 
 #include <boost/interprocess/detail/config_begin.hpp>
 #include <boost/interprocess/detail/workaround.hpp>
 #include <boost/interprocess/creation_tags.hpp>
 #include <boost/interprocess/permissions.hpp>
 #include <boost/interprocess/detail/win32_api.hpp>
 #include <boost/interprocess/detail/posix_time_types_wrk.hpp>
 #include <boost/interprocess/sync/windows/winapi_wrapper_common.hpp>
 #include <boost/interprocess/errors.hpp>
 #include <boost/interprocess/exceptions.hpp>
 #include <limits>
 
 namespace boost {
 namespace interprocess {
 namespace ipcdetail {
 
 class winapi_semaphore_functions
 {
    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
 
    //Non-copyable
    winapi_semaphore_functions(const winapi_semaphore_functions &);
    winapi_semaphore_functions &operator=(const winapi_semaphore_functions &);
    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 
    public:
    winapi_semaphore_functions(void *hnd)
       : m_sem_hnd(hnd)
    {}
 
    void post(long count = 1)
    {
       long prev_count;
       winapi::release_semaphore(m_sem_hnd, count, &prev_count);
    }
 
    void wait()
    {  return winapi_wrapper_wait_for_single_object(m_sem_hnd);  }
 
    bool try_wait()
    {  return winapi_wrapper_try_wait_for_single_object(m_sem_hnd);  }
 
    bool timed_wait(const boost::posix_time::ptime &abs_time)
    {  return winapi_wrapper_timed_wait_for_single_object(m_sem_hnd, abs_time);  }
 
    long value() const
    {
       long l_count, l_limit;
       if(!winapi::get_semaphore_info(m_sem_hnd, l_count, l_limit))
          return 0;
       return l_count;
    }
 
    long limit() const
    {
       long l_count, l_limit;
       if(!winapi::get_semaphore_info(m_sem_hnd, l_count, l_limit))
          return 0;
       return l_limit;
    }
 
    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
    protected:
    void *m_sem_hnd;
    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
 };
 
 
 //Swappable semaphore wrapper
 class winapi_semaphore_wrapper
    : public winapi_semaphore_functions
 {
    winapi_semaphore_wrapper(const winapi_semaphore_wrapper &);
    winapi_semaphore_wrapper &operator=(const winapi_semaphore_wrapper &);
 
    public:
 
    //Long is 32 bits in windows
    static const long MaxCount = long(0x7FFFFFFF);
 
    winapi_semaphore_wrapper(void *hnd = winapi::invalid_handle_value)
       : winapi_semaphore_functions(hnd)
    {}
 
    ~winapi_semaphore_wrapper()
    {  this->close(); }
 
    void *release()
    {
       void *hnd = m_sem_hnd;
       m_sem_hnd = winapi::invalid_handle_value;
       return hnd;
    }
 
    void *handle() const
    {  return m_sem_hnd; }
 
    template <class CharT>
    bool open_or_create( const CharT *name
                       , long sem_count
                       , long max_count
                       , const permissions &perm
                       , bool &created)
    {
       if(m_sem_hnd == winapi::invalid_handle_value){
          m_sem_hnd = winapi::open_or_create_semaphore
             ( name
             , sem_count
             , max_count
             , (winapi::interprocess_security_attributes*)perm.get_permissions()
             );
          created = winapi::get_last_error() != winapi::error_already_exists;
          return m_sem_hnd != winapi::invalid_handle_value;
       }
       else{
          return false;
       }
    }
 
    bool open_semaphore(const char *name)
    {
       if(m_sem_hnd == winapi::invalid_handle_value){
          m_sem_hnd = winapi::open_semaphore(name);
          return m_sem_hnd != winapi::invalid_handle_value;
       }
       else{
          return false;
       }
    }
 
    void close()
    {
       if(m_sem_hnd != winapi::invalid_handle_value){
          winapi::close_handle(m_sem_hnd);
          m_sem_hnd = winapi::invalid_handle_value;
       }
    }
 
    void swap(winapi_semaphore_wrapper &other)
    {  void *tmp = m_sem_hnd; m_sem_hnd = other.m_sem_hnd; other.m_sem_hnd = tmp;   }
 };
 
 }  //namespace ipcdetail {
 }  //namespace interprocess {
 }  //namespace boost {
 
 #include <boost/interprocess/detail/config_end.hpp>
 
 #endif   //BOOST_INTERPROCESS_DETAIL_WINAPI_SEMAPHORE_WRAPPER_HPP