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//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Ion Gaztanaga 2006. 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_FILE_WRAPPER_HPP
#define BOOST_INTERPROCESS_DETAIL_FILE_WRAPPER_HPP
#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/interprocess/detail/os_file_functions.hpp>
#include <boost/interprocess/creation_tags.hpp>
#include <boost/move/move.hpp>
#include <boost/interprocess/creation_tags.hpp>
namespace boost {
namespace interprocess {
namespace ipcdetail{
class file_wrapper
{
/// @cond
BOOST_MOVABLE_BUT_NOT_COPYABLE(file_wrapper)
/// @endcond
public:
//!Default constructor.
//!Represents an empty file_wrapper.
file_wrapper();
//!Creates a file object with name "name" and mode "mode", with the access mode "mode"
//!If the file previously exists, throws an error.
file_wrapper(create_only_t, const char *name, mode_t mode, const permissions &perm = permissions())
{ this->priv_open_or_create(ipcdetail::DoCreate, name, mode, perm); }
//!Tries to create a file with name "name" and mode "mode", with the
//!access mode "mode". If the file previously exists, it tries to open it with mode "mode".
//!Otherwise throws an error.
file_wrapper(open_or_create_t, const char *name, mode_t mode, const permissions &perm = permissions())
{ this->priv_open_or_create(ipcdetail::DoOpenOrCreate, name, mode, perm); }
//!Tries to open a file with name "name", with the access mode "mode".
//!If the file does not previously exist, it throws an error.
file_wrapper(open_only_t, const char *name, mode_t mode)
{ this->priv_open_or_create(ipcdetail::DoOpen, name, mode, permissions()); }
//!Moves the ownership of "moved"'s file to *this.
//!After the call, "moved" does not represent any file.
//!Does not throw
file_wrapper(BOOST_RV_REF(file_wrapper) moved)
: m_handle(file_handle_t(ipcdetail::invalid_file()))
{ this->swap(moved); }
//!Moves the ownership of "moved"'s file to *this.
//!After the call, "moved" does not represent any file.
//!Does not throw
file_wrapper &operator=(BOOST_RV_REF(file_wrapper) moved)
{
file_wrapper tmp(boost::move(moved));
this->swap(tmp);
return *this;
}
//!Swaps to file_wrappers.
//!Does not throw
void swap(file_wrapper &other);
//!Erases a file from the system.
//!Returns false on error. Never throws
static bool remove(const char *name);
//!Sets the size of the file
void truncate(offset_t length);
//!Closes the
//!file
~file_wrapper();
//!Returns the name of the file
//!used in the constructor
const char *get_name() const;
//!Returns the name of the file
//!used in the constructor
bool get_size(offset_t &size) const;
//!Returns access mode
//!used in the constructor
mode_t get_mode() const;
//!Get mapping handle
//!to use with mapped_region
mapping_handle_t get_mapping_handle() const;
private:
//!Closes a previously opened file mapping. Never throws.
void priv_close();
//!Closes a previously opened file mapping. Never throws.
bool priv_open_or_create(ipcdetail::create_enum_t type, const char *filename, mode_t mode, const permissions &perm);
file_handle_t m_handle;
mode_t m_mode;
std::string m_filename;
};
inline file_wrapper::file_wrapper()
: m_handle(file_handle_t(ipcdetail::invalid_file()))
{}
inline file_wrapper::~file_wrapper()
{ this->priv_close(); }
inline const char *file_wrapper::get_name() const
{ return m_filename.c_str(); }
inline bool file_wrapper::get_size(offset_t &size) const
{ return get_file_size((file_handle_t)m_handle, size); }
inline void file_wrapper::swap(file_wrapper &other)
{
std::swap(m_handle, other.m_handle);
std::swap(m_mode, other.m_mode);
m_filename.swap(other.m_filename);
}
inline mapping_handle_t file_wrapper::get_mapping_handle() const
{ return mapping_handle_from_file_handle(m_handle); }
inline mode_t file_wrapper::get_mode() const
{ return m_mode; }
inline bool file_wrapper::priv_open_or_create
(ipcdetail::create_enum_t type,
const char *filename,
mode_t mode,
const permissions &perm = permissions())
{
m_filename = filename;
if(mode != read_only && mode != read_write){
error_info err(mode_error);
throw interprocess_exception(err);
}
//Open file existing native API to obtain the handle
switch(type){
case ipcdetail::DoOpen:
m_handle = open_existing_file(filename, mode);
break;
case ipcdetail::DoCreate:
m_handle = create_new_file(filename, mode, perm);
break;
case ipcdetail::DoOpenOrCreate:
m_handle = create_or_open_file(filename, mode, perm);
break;
default:
{
error_info err = other_error;
throw interprocess_exception(err);
}
}
//Check for error
if(m_handle == invalid_file()){
throw interprocess_exception(error_info(system_error_code()));
}
m_mode = mode;
return true;
}
inline bool file_wrapper::remove(const char *filename)
{ return delete_file(filename); }
inline void file_wrapper::truncate(offset_t length)
{
if(!truncate_file(m_handle, length)){
error_info err(system_error_code());
throw interprocess_exception(err);
}
}
inline void file_wrapper::priv_close()
{
if(m_handle != invalid_file()){
close_file(m_handle);
m_handle = invalid_file();
}
}
} //namespace ipcdetail{
} //namespace interprocess {
} //namespace boost {
#include <boost/interprocess/detail/config_end.hpp>
#endif //BOOST_INTERPROCESS_DETAIL_FILE_WRAPPER_HPP
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