ceph/src/boost/boost/interprocess/xsi_key.hpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 //
   3 // (C) Copyright Ion Gaztanaga 2009. 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
  11 #ifndef BOOST_INTERPROCESS_XSI_KEY_HPP
  12 #define BOOST_INTERPROCESS_XSI_KEY_HPP
  13
  14 #ifndef BOOST_CONFIG_HPP
  15 #  include <boost/config.hpp>
  16 #endif
  17 #
  18 #if defined(BOOST_HAS_PRAGMA_ONCE)
  19 #  pragma once
  20 #endif
  21
  22 #include <boost/interprocess/detail/config_begin.hpp>
  23 #include <boost/interprocess/detail/workaround.hpp>
  24 #include <boost/detail/workaround.hpp>
  25
  26 #if !defined(BOOST_INTERPROCESS_XSI_SHARED_MEMORY_OBJECTS)
  27 #error "This header can't be used in operating systems without XSI (System V) shared memory support"
  28 #endif
  29
  30 #include <boost/interprocess/creation_tags.hpp>
  31 #include <boost/interprocess/exceptions.hpp>
  32 #include <boost/interprocess/detail/utilities.hpp>
  33 #include <boost/move/utility_core.hpp>
  34 #include <boost/interprocess/detail/os_file_functions.hpp>
  35 #include <boost/interprocess/interprocess_fwd.hpp>
  36 #include <boost/interprocess/exceptions.hpp>
  37 #include <sys/types.h>
  38 #include <sys/ipc.h>
  39 #include <cstddef>
  40 #include <boost/cstdint.hpp>
  41
  42 //!\file
  43 //!Describes a class representing a xsi key type.
  44
  45 namespace boost {
  46 namespace interprocess {
  47
  48 //!A class that wraps XSI (System V) key_t type.
  49 //!This type calculates key_t from path and id using ftok,
  50 //!sets key to a specified value,
  51 //!or sets key to IPC_PRIVATE using the default constructor.
  52 class xsi_key
  53 {
  54    public:
  55
  56    //!Default constructor.
  57    //!Represents a private xsi_key.
  58    xsi_key()
  59       : m_key(IPC_PRIVATE)
  60    {}
  61
  62    //!Creates a new XSI key using a specified value. Constructor is explicit to avoid ambiguity with shmid.
  63    explicit xsi_key(key_t key)
  64       : m_key(key)
  65    {}
  66
  67    //!Creates a new XSI  shared memory with a key obtained from a call to ftok (with path
  68    //!"path" and id "id"), of size "size" and permissions "perm".
  69    //!If the shared memory previously exists, throws an error.
  70    xsi_key(const char *path, boost::uint8_t id)
  71    {
  72       key_t key;
  73       if(path){
  74          key  = ::ftok(path, id);
  75          if(((key_t)-1) == key){
  76             error_info err = system_error_code();
  77             throw interprocess_exception(err);
  78          }
  79       }
  80       else{
  81          key = IPC_PRIVATE;
  82       }
  83       m_key = key;
  84    }
  85
  86    //!Returns the internal key_t value
  87    key_t get_key() const
  88    {  return m_key;  }
  89
  90    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
  91    private:
  92    key_t m_key;
  93    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
  94 };
  95
  96 }  //namespace interprocess {
  97 }  //namespace boost {
  98
  99 #include <boost/interprocess/detail/config_end.hpp>
 100
 101 #endif   //BOOST_INTERPROCESS_XSI_KEY_HPP