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Diffstat (limited to 'ext/boost/date_time/microsec_time_clock.hpp')
| -rw-r--r-- | ext/boost/date_time/microsec_time_clock.hpp | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/ext/boost/date_time/microsec_time_clock.hpp b/ext/boost/date_time/microsec_time_clock.hpp new file mode 100644 index 0000000000..e6f3b8ecdf --- /dev/null +++ b/ext/boost/date_time/microsec_time_clock.hpp @@ -0,0 +1,127 @@ +#ifndef DATE_TIME_HIGHRES_TIME_CLOCK_HPP___ +#define DATE_TIME_HIGHRES_TIME_CLOCK_HPP___ + +/* Copyright (c) 2002,2003,2005 CrystalClear Software, Inc. + * Use, modification and distribution is subject to the + * Boost Software License, Version 1.0. (See accompanying + * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt) + * Author: Jeff Garland, Bart Garst + * $Date: 2009-06-04 07:36:43 -0400 (Thu, 04 Jun 2009) $ + */ + + +/*! @file microsec_time_clock.hpp + This file contains a high resolution time clock implementation. +*/ + +#include <boost/cstdint.hpp> +#include <boost/shared_ptr.hpp> +#include <boost/detail/workaround.hpp> +#include <boost/date_time/compiler_config.hpp> +#include <boost/date_time/c_time.hpp> +#include <boost/date_time/time_clock.hpp> +#include <boost/date_time/filetime_functions.hpp> + +#ifdef BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK + +namespace boost { +namespace date_time { + + //! A clock providing microsecond level resolution + /*! A high precision clock that measures the local time + * at a resolution up to microseconds and adjusts to the + * resolution of the time system. For example, for the + * a library configuration with nano second resolution, + * the last 3 places of the fractional seconds will always + * be 000 since there are 1000 nano-seconds in a micro second. + */ + template<class time_type> + class microsec_clock + { + private: + //! Type for the function used to convert time_t to tm + typedef std::tm* (*time_converter)(const std::time_t*, std::tm*); + + public: + typedef typename time_type::date_type date_type; + typedef typename time_type::time_duration_type time_duration_type; + typedef typename time_duration_type::rep_type resolution_traits_type; + + //! return a local time object for the given zone, based on computer clock + //JKG -- looks like we could rewrite this against universal_time + template<class time_zone_type> + static time_type local_time(shared_ptr<time_zone_type> tz_ptr) + { + typedef typename time_type::utc_time_type utc_time_type; + typedef second_clock<utc_time_type> second_clock; + // we'll need to know the utc_offset this machine has + // in order to get a utc_time_type set to utc + utc_time_type utc_time = second_clock::universal_time(); + time_duration_type utc_offset = second_clock::local_time() - utc_time; + // use micro clock to get a local time with sub seconds + // and adjust it to get a true utc time reading with sub seconds + utc_time = microsec_clock<utc_time_type>::local_time() - utc_offset; + return time_type(utc_time, tz_ptr); + } + + //! Returns the local time based on computer clock settings + static time_type local_time() + { + return create_time(&c_time::localtime); + } + + //! Returns the UTC time based on computer settings + static time_type universal_time() + { + return create_time(&c_time::gmtime); + } + + private: + static time_type create_time(time_converter converter) + { +#ifdef BOOST_HAS_GETTIMEOFDAY + timeval tv; + gettimeofday(&tv, 0); //gettimeofday does not support TZ adjust on Linux. + std::time_t t = tv.tv_sec; + boost::uint32_t sub_sec = tv.tv_usec; +#elif defined(BOOST_HAS_FTIME) + winapi::file_time ft; + winapi::get_system_time_as_file_time(ft); + uint64_t micros = winapi::file_time_to_microseconds(ft); // it will not wrap, since ft is the current time + // and cannot be before 1970-Jan-01 + std::time_t t = static_cast<std::time_t>(micros / 1000000UL); // seconds since epoch + // microseconds -- static casts supress warnings + boost::uint32_t sub_sec = static_cast<boost::uint32_t>(micros % 1000000UL); +#else +#error Internal Boost.DateTime error: BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK is defined, however neither gettimeofday nor FILETIME support is detected. +#endif + + std::tm curr; + std::tm* curr_ptr = converter(&t, &curr); + date_type d(curr_ptr->tm_year + 1900, + curr_ptr->tm_mon + 1, + curr_ptr->tm_mday); + + //The following line will adjust the fractional second tick in terms + //of the current time system. For example, if the time system + //doesn't support fractional seconds then res_adjust returns 0 + //and all the fractional seconds return 0. + int adjust = static_cast< int >(resolution_traits_type::res_adjust() / 1000000); + + time_duration_type td(curr_ptr->tm_hour, + curr_ptr->tm_min, + curr_ptr->tm_sec, + sub_sec * adjust); + + return time_type(d,td); + } + }; + + +} } //namespace date_time + +#endif //BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK + + +#endif + |