1 /*
2  *          Copyright Andrey Semashev 2007 - 2015.
3  * Distributed under the Boost Software License, Version 1.0.
4  *    (See accompanying file LICENSE_1_0.txt or copy at
5  *          http://www.boost.org/LICENSE_1_0.txt)
6  */
7 /*!
8  * \file   clock.hpp
9  * \author Andrey Semashev
10  * \date   01.12.2007
11  *
12  * The header contains wall clock attribute implementation and typedefs.
13  */
14 
15 #ifndef BOOST_LOG_ATTRIBUTES_CLOCK_HPP_INCLUDED_
16 #define BOOST_LOG_ATTRIBUTES_CLOCK_HPP_INCLUDED_
17 
18 #include <boost/log/detail/config.hpp>
19 #include <boost/log/attributes/attribute.hpp>
20 #include <boost/log/attributes/attribute_value.hpp>
21 #include <boost/log/attributes/attribute_cast.hpp>
22 #include <boost/log/attributes/attribute_value_impl.hpp>
23 #include <boost/log/attributes/time_traits.hpp>
24 #include <boost/log/detail/header.hpp>
25 
26 #ifdef BOOST_HAS_PRAGMA_ONCE
27 #pragma once
28 #endif
29 
30 namespace boost {
31 
32 BOOST_LOG_OPEN_NAMESPACE
33 
34 namespace attributes {
35 
36 /*!
37  * \brief A class of an attribute that makes an attribute value of the current date and time
38  *
39  * The attribute generates current time stamp as a value. The type of the attribute value
40  * is determined with time traits passed to the class template as a template parameter.
41  * The time traits provided by the library use \c boost::posix_time::ptime as the time type.
42  *
43  * Time traits also determine the way time is acquired. There are two types of time traits
44  * provided by the library: \c utc_time_traits and \c local_time_traits. The first returns UTC time,
45  * the second returns local time.
46  */
47 template< typename TimeTraitsT >
48 class basic_clock :
49     public attribute
50 {
51 public:
52     //! Generated value type
53     typedef typename TimeTraitsT::time_type value_type;
54 
55 protected:
56     //! Attribute factory implementation
57     struct BOOST_SYMBOL_VISIBLE impl :
58         public attribute::impl
59     {
get_valueboost::attributes::basic_clock::impl60         attribute_value get_value()
61         {
62             typedef attribute_value_impl< value_type > result_value;
63             return attribute_value(new result_value(TimeTraitsT::get_clock()));
64         }
65     };
66 
67 public:
68     /*!
69      * Default constructor
70      */
basic_clock()71     basic_clock() : attribute(new impl())
72     {
73     }
74     /*!
75      * Constructor for casting support
76      */
basic_clock(cast_source const & source)77     explicit basic_clock(cast_source const& source) : attribute(source.as< impl >())
78     {
79     }
80 };
81 
82 //! Attribute that returns current UTC time
83 typedef basic_clock< utc_time_traits > utc_clock;
84 //! Attribute that returns current local time
85 typedef basic_clock< local_time_traits > local_clock;
86 
87 } // namespace attributes
88 
89 BOOST_LOG_CLOSE_NAMESPACE // namespace log
90 
91 } // namespace boost
92 
93 #include <boost/log/detail/footer.hpp>
94 
95 #endif // BOOST_LOG_ATTRIBUTES_CLOCK_HPP_INCLUDED_
96