Chris@16: //////////////////////////////////////////////////////////////////////////////
Chris@16: //
Chris@16: // (C) Copyright Ion Gaztanaga 2009-2012. Distributed under the Boost
Chris@16: // Software License, Version 1.0. (See accompanying file
Chris@16: // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: //
Chris@16: // See http://www.boost.org/libs/interprocess for documentation.
Chris@16: //
Chris@16: //////////////////////////////////////////////////////////////////////////////
Chris@16: 
Chris@16: #ifndef BOOST_INTERPROCESS_XSI_SHARED_MEMORY_HPP
Chris@16: #define BOOST_INTERPROCESS_XSI_SHARED_MEMORY_HPP
Chris@16: 
Chris@101: #ifndef BOOST_CONFIG_HPP
Chris@101: #  include <boost/config.hpp>
Chris@101: #endif
Chris@101: #
Chris@101: #if defined(BOOST_HAS_PRAGMA_ONCE)
Chris@101: #  pragma once
Chris@101: #endif
Chris@101: 
Chris@16: #include <boost/interprocess/detail/config_begin.hpp>
Chris@16: #include <boost/interprocess/detail/workaround.hpp>
Chris@16: 
Chris@16: #if !defined(BOOST_INTERPROCESS_XSI_SHARED_MEMORY_OBJECTS)
Chris@16: #error "This header can't be used in operating systems without XSI (System V) shared memory support"
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/interprocess/creation_tags.hpp>
Chris@16: #include <boost/interprocess/exceptions.hpp>
Chris@16: #include <boost/interprocess/detail/utilities.hpp>
Chris@101: 
Chris@16: #include <boost/interprocess/detail/os_file_functions.hpp>
Chris@16: #include <boost/interprocess/interprocess_fwd.hpp>
Chris@16: #include <boost/interprocess/exceptions.hpp>
Chris@16: #include <boost/interprocess/xsi_key.hpp>
Chris@16: #include <boost/interprocess/permissions.hpp>
Chris@101: #include <boost/interprocess/detail/simple_swap.hpp>
Chris@101: // move
Chris@101: #include <boost/move/utility_core.hpp>
Chris@101: // other boost
Chris@101: #include <boost/cstdint.hpp>
Chris@101: // std
Chris@101: #include <cstddef>
Chris@101: // OS
Chris@16: #include <sys/shm.h>
Chris@101: 
Chris@16: 
Chris@16: //!\file
Chris@16: //!Describes a class representing a native xsi shared memory.
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace interprocess {
Chris@16: 
Chris@16: //!A class that wraps XSI (System V) shared memory.
Chris@16: //!Unlike shared_memory_object, xsi_shared_memory needs a valid
Chris@16: //!xsi_key to identify a shared memory object.
Chris@16: //!
Chris@16: //!Warning: XSI shared memory and interprocess portable
Chris@16: //!shared memory (boost::interprocess::shared_memory_object)
Chris@16: //!can't communicate between them.
Chris@16: class xsi_shared_memory
Chris@16: {
Chris@101:    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
Chris@16:    //Non-copyable and non-assignable
Chris@16:    BOOST_MOVABLE_BUT_NOT_COPYABLE(xsi_shared_memory)
Chris@101:    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
Chris@16: 
Chris@16:    public:
Chris@16:    //!Default constructor.
Chris@16:    //!Represents an empty xsi_shared_memory.
Chris@16:    xsi_shared_memory();
Chris@16: 
Chris@16:    //!Initializes *this with a shmid previously obtained (possibly from another process)
Chris@16:    //!This lower-level initializer allows shared memory mapping without having a key.
Chris@16:    xsi_shared_memory(open_only_t, int shmid)
Chris@16:       : m_shmid (shmid)
Chris@16:    {}
Chris@16: 
Chris@16:    //!Creates a new XSI shared memory from 'key', with size "size" and permissions "perm".
Chris@16:    //!If the shared memory previously exists, throws an error.
Chris@16:    xsi_shared_memory(create_only_t, const xsi_key &key, std::size_t size, const permissions& perm = permissions())
Chris@16:    {  this->priv_open_or_create(ipcdetail::DoCreate, key, perm, size);  }
Chris@16: 
Chris@16:    //!Opens an existing shared memory with identifier 'key' or creates a new XSI shared memory from
Chris@16:    //!identifier 'key', with size "size" and permissions "perm".
Chris@16:    xsi_shared_memory(open_or_create_t, const xsi_key &key, std::size_t size, const permissions& perm = permissions())
Chris@16:    {  this->priv_open_or_create(ipcdetail::DoOpenOrCreate, key, perm, size);  }
Chris@16: 
Chris@16:    //!Tries to open a XSI shared memory with identifier 'key'
Chris@16:    //!If the shared memory does not previously exist, it throws an error.
Chris@16:    xsi_shared_memory(open_only_t, const xsi_key &key)
Chris@16:    {  this->priv_open_or_create(ipcdetail::DoOpen, key, permissions(), 0);  }
Chris@16: 
Chris@16:    //!Moves the ownership of "moved"'s shared memory object to *this.
Chris@16:    //!After the call, "moved" does not represent any shared memory object.
Chris@16:    //!Does not throw
Chris@16:    xsi_shared_memory(BOOST_RV_REF(xsi_shared_memory) moved)
Chris@16:       : m_shmid(-1)
Chris@16:    {  this->swap(moved);   }
Chris@16: 
Chris@16:    //!Moves the ownership of "moved"'s shared memory to *this.
Chris@16:    //!After the call, "moved" does not represent any shared memory.
Chris@16:    //!Does not throw
Chris@16:    xsi_shared_memory &operator=(BOOST_RV_REF(xsi_shared_memory) moved)
Chris@16:    {
Chris@16:       xsi_shared_memory tmp(boost::move(moved));
Chris@16:       this->swap(tmp);
Chris@16:       return *this;
Chris@16:    }
Chris@16: 
Chris@16:    //!Swaps two xsi_shared_memorys. Does not throw
Chris@16:    void swap(xsi_shared_memory &other);
Chris@16: 
Chris@16:    //!Destroys *this. The shared memory won't be destroyed, just
Chris@16:    //!this connection to it. Use remove() to destroy the shared memory.
Chris@16:    ~xsi_shared_memory();
Chris@16: 
Chris@16:    //!Returns the shared memory ID that
Chris@16:    //!identifies the shared memory
Chris@16:    int get_shmid() const;
Chris@16: 
Chris@16:    //!Returns the mapping handle.
Chris@16:    //!Never throws
Chris@16:    mapping_handle_t get_mapping_handle() const;
Chris@16: 
Chris@16:    //!Erases the XSI shared memory object identified by shmid
Chris@16:    //!from the system.
Chris@16:    //!Returns false on error. Never throws
Chris@16:    static bool remove(int shmid);
Chris@16: 
Chris@101:    #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
Chris@16:    private:
Chris@16: 
Chris@16:    //!Closes a previously opened file mapping. Never throws.
Chris@16:    bool priv_open_or_create( ipcdetail::create_enum_t type
Chris@16:                            , const xsi_key &key
Chris@16:                            , const permissions& perm
Chris@16:                            , std::size_t size);
Chris@16:    int            m_shmid;
Chris@101:    #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
Chris@16: };
Chris@16: 
Chris@101: #if !defined(BOOST_INTERPROCESS_DOXYGEN_INVOKED)
Chris@16: 
Chris@16: inline xsi_shared_memory::xsi_shared_memory()
Chris@16:    :  m_shmid(-1)
Chris@16: {}
Chris@16: 
Chris@16: inline xsi_shared_memory::~xsi_shared_memory()
Chris@16: {}
Chris@16: 
Chris@16: inline int xsi_shared_memory::get_shmid() const
Chris@16: {  return m_shmid; }
Chris@16: 
Chris@16: inline void xsi_shared_memory::swap(xsi_shared_memory &other)
Chris@16: {
Chris@101:    (simple_swap)(m_shmid, other.m_shmid);
Chris@16: }
Chris@16: 
Chris@16: inline mapping_handle_t xsi_shared_memory::get_mapping_handle() const
Chris@16: {  mapping_handle_t mhnd = { m_shmid, true};   return mhnd;   }
Chris@16: 
Chris@16: inline bool xsi_shared_memory::priv_open_or_create
Chris@16:    (ipcdetail::create_enum_t type, const xsi_key &key, const permissions& permissions, std::size_t size)
Chris@16: {
Chris@16:    int perm = permissions.get_permissions();
Chris@16:    perm &= 0x01FF;
Chris@16:    int shmflg = perm;
Chris@16: 
Chris@16:    switch(type){
Chris@16:       case ipcdetail::DoOpen:
Chris@16:          shmflg |= 0;
Chris@16:       break;
Chris@16:       case ipcdetail::DoCreate:
Chris@16:          shmflg |= IPC_CREAT | IPC_EXCL;
Chris@16:       break;
Chris@16:       case ipcdetail::DoOpenOrCreate:
Chris@16:          shmflg |= IPC_CREAT;
Chris@16:       break;
Chris@16:       default:
Chris@16:          {
Chris@16:             error_info err = other_error;
Chris@16:             throw interprocess_exception(err);
Chris@16:          }
Chris@16:    }
Chris@16: 
Chris@16:    int ret = ::shmget(key.get_key(), size, shmflg);
Chris@16:    int shmid = ret;
Chris@16:    if((type == ipcdetail::DoOpen) && (-1 != ret)){
Chris@16:       //Now get the size
Chris@16:       ::shmid_ds xsi_ds;
Chris@16:       ret = ::shmctl(ret, IPC_STAT, &xsi_ds);
Chris@16:       size = xsi_ds.shm_segsz;
Chris@16:    }
Chris@16:    if(-1 == ret){
Chris@16:       error_info err = system_error_code();
Chris@16:       throw interprocess_exception(err);
Chris@16:    }
Chris@16: 
Chris@16:    m_shmid = shmid;
Chris@16:    return true;
Chris@16: }
Chris@16: 
Chris@16: inline bool xsi_shared_memory::remove(int shmid)
Chris@16: {  return -1 != ::shmctl(shmid, IPC_RMID, 0); }
Chris@16: 
Chris@101: #endif   //#ifndef BOOST_INTERPROCESS_DOXYGEN_INVOKED
Chris@16: 
Chris@16: }  //namespace interprocess {
Chris@16: }  //namespace boost {
Chris@16: 
Chris@16: #include <boost/interprocess/detail/config_end.hpp>
Chris@16: 
Chris@16: #endif   //BOOST_INTERPROCESS_XSI_SHARED_MEMORY_HPP