//////////////////////////////////////////////////////////////////////////////

//

// (C) Copyright Ion Gaztanaga 2009. 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_XSI_KEY_HPP

#define BOOST_INTERPROCESS_XSI_KEY_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/detail/workaround.hpp>

#if !defined(BOOST_INTERPROCESS_XSI_SHARED_MEMORY_OBJECTS)

#error "This header can't be used in operating systems without XSI (System V) shared memory support"

#endif

#include <boost/interprocess/creation_tags.hpp>

#include <boost/interprocess/exceptions.hpp>

#include <boost/interprocess/detail/utilities.hpp>

#include <boost/move/utility_core.hpp>

#include <boost/interprocess/detail/os_file_functions.hpp>

#include <boost/interprocess/interprocess_fwd.hpp>

#include <boost/interprocess/exceptions.hpp>

#include <sys/types.h>

#include <sys/ipc.h>

#include <cstddef>

#include <boost/cstdint.hpp>

//!\file

//!Describes a class representing a xsi key type.

namespace boost {

namespace interprocess {

//!A class that wraps XSI (System V) key_t type.

//!This type calculates key_t from path and id using ftok,

//!sets key to a specified value,

//!or sets key to IPC_PRIVATE using the default constructor.

class xsi_key

{

   public:

   //!Default constructor.

   //!Represents a private xsi_key.

   xsi_key()

      : m_key(IPC_PRIVATE)

   {}

   //!Creates a new XSI key using a specified value. Constructor is explicit to avoid ambiguity with shmid.

   explicit xsi_key(key_t key)

      : m_key(key)

   {}

   //!Creates a new XSI  shared memory with a key obtained from a call to ftok (with path

   //!"path" and id "id"), of size "size" and permissions "perm".

   //!If the shared memory previously exists, throws an error.

   xsi_key(const char *path, boost::uint8_t id)

   {

      key_t key;

      if(path){

         key  = ::ftok(path, id);

         if(((key_t)-1) == key){

            error_info err = system_error_code();

            throw interprocess_exception(err);

         }

      }

      else{

         key = IPC_PRIVATE;

      }

      m_key = key;

   }

   //!Returns the internal key_t value

   key_t get_key() const

   {  return m_key;  }

   #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)

   private:

   key_t m_key;

   #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED

};

}  //namespace interprocess {

}  //namespace boost {

#include <boost/interprocess/detail/config_end.hpp>

#endif   //BOOST_INTERPROCESS_XSI_KEY_HPP