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#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: 2008-02-27 15:00:24 -0500 (Wed, 27 Feb 2008) $
*/
/*! @file microsec_time_clock.hpp
This file contains a high resolution time clock implementation.
*/
#include <boost/detail/workaround.hpp>
#include "boost/date_time/c_time.hpp"
#include "boost/date_time/time_clock.hpp"
#include "boost/cstdint.hpp"
#include "boost/shared_ptr.hpp"
#ifdef BOOST_HAS_FTIME
#include <windows.h>
#endif
#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
{
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);
}
private:
// we want this enum available for both platforms yet still private
enum TZ_FOR_CREATE { LOCAL, GMT };
public:
#ifdef BOOST_HAS_GETTIMEOFDAY
//! Return the local time based on computer clock settings
static time_type local_time() {
return create_time(LOCAL);
}
//! Get the current day in universal date as a ymd_type
static time_type universal_time()
{
return create_time(GMT);
}
private:
static time_type create_time(TZ_FOR_CREATE tz) {
timeval tv;
gettimeofday(&tv, 0); //gettimeofday does not support TZ adjust on Linux.
std::time_t t = tv.tv_sec;
boost::uint32_t fs = tv.tv_usec;
std::tm curr, *curr_ptr = 0;
if (tz == LOCAL) {
curr_ptr = c_time::localtime(&t, &curr);
} else {
curr_ptr = c_time::gmtime(&t, &curr);
}
date_type d(curr_ptr->tm_year + 1900,
curr_ptr->tm_mon + 1,
curr_ptr->tm_mday);
//The following line will adjusts 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 = resolution_traits_type::res_adjust()/1000000;
time_duration_type td(curr_ptr->tm_hour,
curr_ptr->tm_min,
curr_ptr->tm_sec,
fs*adjust);
return time_type(d,td);
}
#endif // BOOST_HAS_GETTIMEOFDAY
#ifdef BOOST_HAS_FTIME
//! Return the local time based on computer clock settings
static time_type local_time() {
FILETIME ft;
#if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3205))
// Some runtime library implementations expect local times as the norm for ctime.
FILETIME ft_utc;
GetSystemTimeAsFileTime(&ft_utc);
FileTimeToLocalFileTime(&ft_utc,&ft);
#elif defined(BOOST_NO_GETSYSTEMTIMEASFILETIME)
SYSTEMTIME st;
GetSystemTime( &st );
SystemTimeToFileTime( &st, &ft );
#else
GetSystemTimeAsFileTime(&ft);
#endif
return create_time(ft, LOCAL);
}
//! Return the UTC time based on computer settings
static time_type universal_time() {
FILETIME ft;
#if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3205))
// Some runtime library implementations expect local times as the norm for ctime.
FILETIME ft_utc;
GetSystemTimeAsFileTime(&ft_utc);
FileTimeToLocalFileTime(&ft_utc,&ft);
#elif defined(BOOST_NO_GETSYSTEMTIMEASFILETIME)
SYSTEMTIME st;
GetSystemTime( &st );
SystemTimeToFileTime( &st, &ft );
#else
GetSystemTimeAsFileTime(&ft);
#endif
return create_time(ft, GMT);
}
private:
static time_type create_time(FILETIME& ft, TZ_FOR_CREATE tz) {
// offset is difference (in 100-nanoseconds) from
// 1970-Jan-01 to 1601-Jan-01
boost::uint64_t c1 = 27111902;
boost::uint64_t c2 = 3577643008UL; // 'UL' removes compiler warnings
const boost::uint64_t OFFSET = (c1 << 32) + c2;
boost::uint64_t filetime = ft.dwHighDateTime;
filetime = filetime << 32;
filetime += ft.dwLowDateTime;
filetime -= OFFSET;
// filetime now holds 100-nanoseconds since 1970-Jan-01
// microseconds -- static casts supress warnings
boost::uint32_t sub_sec = static_cast<boost::uint32_t>((filetime % 10000000) / 10);
std::time_t t = static_cast<time_t>(filetime / 10000000); // seconds since epoch
std::tm curr, *curr_ptr = 0;
if (tz == LOCAL) {
curr_ptr = c_time::localtime(&t, &curr);
}
else {
curr_ptr = c_time::gmtime(&t, &curr);
}
date_type d(curr_ptr->tm_year + 1900,
curr_ptr->tm_mon + 1,
curr_ptr->tm_mday);
//The following line will adjusts 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);
//st.wMilliseconds * adjust);
return time_type(d,td);
}
#endif // BOOST_HAS_FTIME
};
} } //namespace date_time
#endif //BOOST_DATE_TIME_HAS_HIGH_PRECISION_CLOCK
#endif
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