ceph/src/boost/boost/interprocess/indexes/null_index.hpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 //
   3 // (C) Copyright Ion Gaztanaga 2005-2012. Distributed under the Boost
   4 // Software License, Version 1.0. (See accompanying file
   5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // See http://www.boost.org/libs/interprocess for documentation.
   8 //
   9 //////////////////////////////////////////////////////////////////////////////
  10 #ifndef BOOST_INTERPROCESS_NULL_INDEX_HPP
  11 #define BOOST_INTERPROCESS_NULL_INDEX_HPP
  12
  13 #ifndef BOOST_CONFIG_HPP
  14 #  include <boost/config.hpp>
  15 #endif
  16 #
  17 #if defined(BOOST_HAS_PRAGMA_ONCE)
  18 #  pragma once
  19 #endif
  20
  21 #include <boost/interprocess/detail/config_begin.hpp>
  22 #include <boost/interprocess/detail/workaround.hpp>
  23
  24 #include <boost/interprocess/offset_ptr.hpp>
  25
  26 //!\file
  27 //!Describes a null index adaptor, so that if we don't want to construct
  28 //!named objects, we can use this null index type to save resources.
  29
  30 namespace boost {
  31 namespace interprocess {
  32
  33 //!Null index type
  34 //!used to save compilation time when
  35 //!named indexes are not needed.
  36 template <class MapConfig>
  37 class null_index
  38 {
  39    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
  40    typedef typename MapConfig::
  41       segment_manager_base    segment_manager_base;
  42    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
  43
  44    public:
  45    typedef int * iterator;
  46    typedef const int * const_iterator;
  47
  48    //!begin() is equal
  49    //!to end()
  50    const_iterator begin() const
  51    {  return const_iterator(0);  }
  52
  53    //!begin() is equal
  54    //!to end()
  55    iterator begin()
  56    {  return iterator(0);  }
  57
  58    //!begin() is equal
  59    //!to end()
  60    const_iterator end() const
  61    {  return const_iterator(0);  }
  62
  63    //!begin() is equal
  64    //!to end()
  65    iterator end()
  66    {  return iterator(0);  }
  67
  68    //!Empty constructor
  69    null_index(segment_manager_base *){}
  70 };
  71
  72 }}   //namespace boost { namespace interprocess {
  73
  74 #include <boost/interprocess/detail/config_end.hpp>
  75
  76 #endif   //#ifndef BOOST_INTERPROCESS_NULL_INDEX_HPP