boost/log/utility/ipc/object_name.hpp
/* * Copyright Andrey Semashev 2016. * 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) */ /*! * \file utility/ipc/object_name.hpp * \author Andrey Semashev * \date 05.03.2016 * * The header contains declaration of a system object name wrapper. */ #ifndef BOOST_LOG_UTILITY_IPC_OBJECT_NAME_HPP_INCLUDED_ #define BOOST_LOG_UTILITY_IPC_OBJECT_NAME_HPP_INCLUDED_ #include <boost/log/detail/config.hpp> #include <cstddef> #include <iosfwd> #include <string> #include <boost/move/core.hpp> #include <boost/log/detail/header.hpp> #ifdef BOOST_HAS_PRAGMA_ONCE #pragma once #endif namespace boost { BOOST_LOG_OPEN_NAMESPACE namespace ipc { /*! * \brief A system object name class * * In order to identify a system-wide object such as a shared memory segment or a named synchronization primitive the object has to be given a name. * The format of the name is specific to the operating system and the \c object_name class provides an abstraction for names of objects. It also * provides means for scoping, which allows to avoid name clashes between different processes. * * The object name is a UTF-8 encoded string. The portable object name should consist of the following characters: * * <pre> * A B C D E F G H I J K L M N O P Q R S T U V W X Y Z * a b c d e f g h i j k l m n o p q r s t u v w x y z * 0 1 2 3 4 5 6 7 8 9 . _ - * </pre> * * \note The character set corresponds to the POSIX Portable Filename Character Set (http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_278). * * Use of other characters may result in non-portable system-specific behavior. * * The name can have one of the following scopes: * * \li \c global - objects within this scope are visible to any process on the system. In order to use this scope the process may need to have * extended privileges. This scope is not available for Windows Store applications. * \li \c user - objects within this scope can be opened by processes running under the same user as the current process. * \li \c session - objects within this scope are visible to processes within the session of the current process. The definition of a session may vary between * operating systems. On POSIX, a session is typically a group of processes attached to a single virtual terminal device. On Windows a session is * started when a user logs into the system. There is also a separate session for Windows services. * \li \c process_group - objects within this scope are visible to processes within the process group of the current process. Currently, on Windows all processes * running in the current session are considered members of the same process group. This may change in future. * * The scopes are not overlapping. For instance, if an object is created in the global scope, the object cannot be opened with the same name but in user's scope. * * Note that name scoping is not a security feature. On some systems any process on the system has technical capability to open objects within any scope. * The scope is only used to help avoid name clashes between processes using \c object_name to identify objects. */ class object_name { public: //! Name scopes enum scope { global, //!< The name has global scope; any process in the system has the potential to open the resource identified by the name user, //!< The name is limited to processes running under the current user session, //!< The name is limited to processes running in the current login session process_group //!< The name is limited to processes running in the current process group }; #if !defined(BOOST_LOG_DOXYGEN_PASS) BOOST_COPYABLE_AND_MOVABLE(object_name) private: std::string m_name; #endif // !defined(BOOST_LOG_DOXYGEN_PASS) public: /*! * Default constructor. The method creates an empty object name. * * \post <tt>empty() == true</tt> */ object_name() BOOST_NOEXCEPT { } /*! * Move constructor. */ object_name(BOOST_RV_REF(object_name) that) BOOST_NOEXCEPT { m_name.swap(that.m_name); } /*! * Copy constructor. */ object_name(object_name const& that) : m_name(that.m_name) { } /*! * Constructor from the native string. * * \param str The object name string, must not be \c NULL. The string format is specific to the operating system. */ static object_name from_native(const char* str) { object_name name; name.m_name = str; return name; } /*! * Constructor from the native string. * * \param str The object name string. The string format is specific to the operating system. */ static object_name from_native(std::string const& str) { object_name name; name.m_name = str; return name; } /*! * Constructor from the object name * \param ns The scope of the object name * \param str The object name, must not be NULL. */ BOOST_LOG_API object_name(scope ns, const char* str); /*! * Constructor from the object name * \param ns The scope of the object name * \param str The object name */ BOOST_LOG_API object_name(scope ns, std::string const& str); /*! * Move assignment */ object_name& operator= (BOOST_RV_REF(object_name) that) BOOST_NOEXCEPT { m_name.clear(); m_name.swap(that.m_name); return *this; } /*! * Copy assignment */ object_name& operator= (BOOST_COPY_ASSIGN_REF(object_name) that) { m_name = that.m_name; return *this; } /*! * Returns \c true if the object name is empty */ bool empty() const BOOST_NOEXCEPT { return m_name.empty(); } /*! * Returns length of the name, in bytes */ std::size_t size() const BOOST_NOEXCEPT { return m_name.size(); } /*! * Returns the name string */ const char* c_str() const BOOST_NOEXCEPT { return m_name.c_str(); } /*! * Swaps the object name with another object name */ void swap(object_name& that) BOOST_NOEXCEPT { m_name.swap(that.m_name); } /*! * Swaps two object names */ friend void swap(object_name& left, object_name& right) BOOST_NOEXCEPT { left.swap(right); } /*! * Returns string representation of the object name */ friend std::string to_string(object_name const& name) { return name.m_name; } /*! * Equality operator */ friend bool operator== (object_name const& left, object_name const& right) BOOST_NOEXCEPT { return left.m_name == right.m_name; } /*! * Inequality operator */ friend bool operator!= (object_name const& left, object_name const& right) BOOST_NOEXCEPT { return left.m_name != right.m_name; } /*! * Less operator */ friend bool operator< (object_name const& left, object_name const& right) BOOST_NOEXCEPT { return left.m_name < right.m_name; } /*! * Greater operator */ friend bool operator> (object_name const& left, object_name const& right) BOOST_NOEXCEPT { return left.m_name > right.m_name; } /*! * Less or equal operator */ friend bool operator<= (object_name const& left, object_name const& right) BOOST_NOEXCEPT { return left.m_name <= right.m_name; } /*! * Greater or equal operator */ friend bool operator>= (object_name const& left, object_name const& right) BOOST_NOEXCEPT { return left.m_name >= right.m_name; } /*! * Stream ouput operator */ template< typename CharT, typename TraitsT > friend std::basic_ostream< CharT, TraitsT >& operator<< (std::basic_ostream< CharT, TraitsT >& strm, object_name const& name) { strm << name.c_str(); return strm; } }; } // namespace ipc BOOST_LOG_CLOSE_NAMESPACE // namespace log } // namespace boost #include <boost/log/detail/footer.hpp> #endif // BOOST_LOG_UTILITY_IPC_OBJECT_NAME_HPP_INCLUDED_