1 #ifndef POSIX_TIME_CONVERSION_HPP___
2 #define POSIX_TIME_CONVERSION_HPP___
4 /* Copyright (c) 2002-2005 CrystalClear Software, Inc.
5 * Use, modification and distribution is subject to the
6 * Boost Software License, Version 1.0. (See accompanying
7 * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
8 * Author: Jeff Garland, Bart Garst
9 * $Date: 2010-06-09 14:10:13 -0400 (Wed, 09 Jun 2010) $
13 #include <boost/date_time/posix_time/ptime.hpp>
14 #include <boost/date_time/posix_time/posix_time_duration.hpp>
15 #include <boost/date_time/filetime_functions.hpp>
16 #include <boost/date_time/c_time.hpp>
17 #include <boost/date_time/time_resolution_traits.hpp> // absolute_value
18 #include <boost/date_time/gregorian/conversion.hpp>
22 namespace posix_time {
25 //! Function that converts a time_t into a ptime.
27 ptime from_time_t(std::time_t t)
29 ptime start(gregorian::date(1970,1,1));
30 return start + seconds(static_cast<long>(t));
33 //! Convert a time to a tm structure truncating any fractional seconds
35 std::tm to_tm(const boost::posix_time::ptime& t) {
36 std::tm timetm = boost::gregorian::to_tm(t.date());
37 boost::posix_time::time_duration td = t.time_of_day();
38 timetm.tm_hour = td.hours();
39 timetm.tm_min = td.minutes();
40 timetm.tm_sec = td.seconds();
41 timetm.tm_isdst = -1; // -1 used when dst info is unknown
44 //! Convert a time_duration to a tm structure truncating any fractional seconds and zeroing fields for date components
46 std::tm to_tm(const boost::posix_time::time_duration& td) {
48 std::memset(&timetm, 0, sizeof(timetm));
49 timetm.tm_hour = date_time::absolute_value(td.hours());
50 timetm.tm_min = date_time::absolute_value(td.minutes());
51 timetm.tm_sec = date_time::absolute_value(td.seconds());
52 timetm.tm_isdst = -1; // -1 used when dst info is unknown
56 //! Convert a tm struct to a ptime ignoring is_dst flag
58 ptime ptime_from_tm(const std::tm& timetm) {
59 boost::gregorian::date d = boost::gregorian::date_from_tm(timetm);
60 return ptime(d, time_duration(timetm.tm_hour, timetm.tm_min, timetm.tm_sec));
64 #if defined(BOOST_HAS_FTIME)
66 //! Function to create a time object from an initialized FILETIME struct.
67 /*! Function to create a time object from an initialized FILETIME struct.
68 * A FILETIME struct holds 100-nanosecond units (0.0000001). When
69 * built with microsecond resolution the FILETIME's sub second value
70 * will be truncated. Nanosecond resolution has no truncation.
72 * \note FILETIME is part of the Win32 API, so it is not portable to non-windows
75 * \note The function is templated on the FILETIME type, so that
76 * it can be used with both native FILETIME and the ad-hoc
77 * boost::date_time::winapi::file_time type.
79 template< typename TimeT, typename FileTimeT >
81 TimeT from_ftime(const FileTimeT& ft)
83 return boost::date_time::time_from_ftime<TimeT>(ft);
86 #endif // BOOST_HAS_FTIME
88 } } //namespace boost::posix_time