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Embedded Template Library
Chrono
Clocks

Clocks

Macros

Default macro definitions.
Define these in etl_profile.h to set your own duration types for the clocks.

Macro Definition
ETL_CHRONO_SYSTEM_CLOCK_DURATION etl::chrono::nanoseconds
ETL_CHRONO_SYSTEM_CLOCK_IS_STEADY true
ETL_CHRONO_HIGH_RESOLUTION_CLOCK_DURATION etl::chrono::nanoseconds
ETL_CHRONO_HIGH_RESOLUTION_CLOCK_IS_STEADY true
ETL_CHRONO_STEADY_CLOCK_DURATION etl::chrono::nanoseconds

Platform clock access

Declarations of the functions that must be defined to interface the clocks with the underlying platform.

extern "C" ETL_CHRONO_SYSTEM_CLOCK_DURATION::rep          etl_get_system_clock();
extern "C" ETL_CHRONO_HIGH_RESOLUTION_CLOCK_DURATION::rep etl_get_high_resolution_clock();
extern "C" ETL_CHRONO_STEADY_CLOCK_DURATION::rep          etl_get_steady_clock();

These functions must return the current count of the underlying clock. The value is in terms of the clock duration defined for that clock.

Example
If the system_clock duration is set to etl::chrono::nanoseconds, then a return value of 1000 represents 1000ns.

system_clock 

class system_clock

Member types 

using duration   = ETL_CHRONO_SYSTEM_CLOCK_DURATION
using rep        = duration::rep
using period     = duration::period
using time_point = time_point<system_clock, duration>

Member functions 

static time_point  now() ETL_NOEXCEPT
static time_t      to_time_t(const time_point& t) ETL_NOEXCEPT
static time_point  from_time_t(time_t t) ETL_NOEXCEPT

high_resolution_clock 

class high_resolution_clock

Member types 

using duration   = ETL_CHRONO_HIGH_RESOLUTION_CLOCK_DURATION
using rep        = duration::rep
using period     = duration::period
using time_point = time_point<high_resolution_clock, duration>

Member functions 

static time_point now() ETL_NOEXCEPT

steady_clock 

class steady_clock

Member types 

using duration   = ETL_CHRONO_STEADY_CLOCK_DURATION
using rep        = duration::rep
using period     = duration::period
using time_point = time_point<steady_clock, duration>

Member functions 

static time_point now() ETL_NOEXCEPT

system_time 

template <typename Duration>
using sys_time = etl::chrono::time_point<etl::chrono::system_clock, Duration>

using sys_seconds = sys_time<etl::chrono::seconds>
using sys_days    = sys_time<etl::chrono::days>

local_time 

struct local_t
template <typename TDuration>
using local_time = etl::chrono::time_point<etl::chrono::local_t, TDuration>

using local_seconds = local_time<etl::chrono::seconds>
using local_days    = local_time<etl::chrono::days>

clock_cast

Cast a time point from one clock to another.
This implementation assumes all clock epochs are the same.

template <typename TToClock, 
          typename TFromClock, 
          typename TFromDuration>
ETL_CONSTEXPR14 etl::chrono::time_point<TToClock, 
                                        typename TToClock::duration>
  clock_cast(const etl::chrono::time_point<TFromClock, TFromDuration>& from_time_point) ETL_NOEXCEPT
Chrono literalsday