ftime.cpp File Reference

#include <corecrt_internal_time.h>
#include <sys/timeb.h>
#include <sys/types.h>

Include dependency graph for ftime.cpp:

Go to the source code of this file.

Macros
#define	DAYLIGHT_TIME   1
#define	STANDARD_TIME   0
#define	UNKNOWN_TIME   -1

Functions
template<typename TimeType , typename TimeBType >
static errno_t __cdecl	common_ftime_s (TimeBType *const tp) throw ()
errno_t __cdecl	_ftime32_s (__timeb32 *const tp)
void __cdecl	_ftime32 (__timeb32 *const tp)
errno_t __cdecl	_ftime64_s (__timeb64 *const tp)
void __cdecl	_ftime64 (__timeb64 *const tp)

Variables
static __time64_t	elapsed_minutes_cache = 0
static int	dstflag_cache = UNKNOWN_TIME

Macro Definition Documentation

DAYLIGHT_TIME

#define DAYLIGHT_TIME   1

Definition at line 22 of file ftime.cpp.

STANDARD_TIME

#define STANDARD_TIME   0

Definition at line 23 of file ftime.cpp.

UNKNOWN_TIME

#define UNKNOWN_TIME   -1

Definition at line 24 of file ftime.cpp.

Function Documentation

_ftime32()

void __cdecl _ftime32

(

__timeb32 *const

tp

)

Definition at line 92 of file ftime.cpp.

{
    _ftime32_s(tp);
}

_ftime32_s()

errno_t __cdecl _ftime32_s

(

__timeb32 *const

tp

)

Definition at line 87 of file ftime.cpp.

{
    return common_ftime_s<__time32_t>(tp);
}

Referenced by _ftime32().

_ftime64()

void __cdecl _ftime64

(

__timeb64 *const

tp

)

Definition at line 102 of file ftime.cpp.

{
    _ftime64_s(tp);
}

_ftime64_s()

errno_t __cdecl _ftime64_s

(

__timeb64 *const

tp

)

Definition at line 97 of file ftime.cpp.

{
    return common_ftime_s<__time64_t>(tp);
}

Referenced by _ftime64().

common_ftime_s()

template<typename TimeType , typename TimeBType >

static errno_t __cdecl common_ftime_s ( TimeBType *const  tp ) throw ( )

static

Definition at line 36 of file ftime.cpp.

{
    _VALIDATE_RETURN_ERRCODE(tp != nullptr, EINVAL)
 
    __tzset();
 
    long timezone = 0;
    _ERRCHECK(_get_timezone(&timezone));
    tp->timezone = static_cast<short>(timezone / 60);
 
    __crt_filetime_union system_time;
    __acrt_GetSystemTimePreciseAsFileTime(&system_time._filetime);
 
    // Obtain the current Daylight Savings Time status.  Note that the status is
    // cached and only updated once per minute, if necessary.
    TimeType const current_minutes_value = static_cast<TimeType>(system_time._scalar / 600000000ll);
    if (static_cast<__time64_t>(current_minutes_value) != elapsed_minutes_cache)
    {
        TIME_ZONE_INFORMATION tz_info;
        DWORD const tz_state = GetTimeZoneInformation(&tz_info);
        if (tz_state == 0xFFFFFFFF)
        {
            dstflag_cache = UNKNOWN_TIME;
        }
        else
        {
            // Must be very careful when determining whether or not Daylight
            // Savings Time is in effect:
            if (tz_state == TIME_ZONE_ID_DAYLIGHT &&
                tz_info.DaylightDate.wMonth != 0 &&
                tz_info.DaylightBias != 0)
            {
                dstflag_cache = DAYLIGHT_TIME;
            }
            else
            {
                // Assume Standard Time:
                dstflag_cache = STANDARD_TIME;
            }
        }
 
        elapsed_minutes_cache = current_minutes_value;
    }
 
    tp->dstflag = static_cast<short>(dstflag_cache);
    tp->millitm = static_cast<unsigned short>((system_time._scalar / 10000ll) % 1000ll);
    tp->time    = static_cast<TimeType>((system_time._scalar - _EPOCH_BIAS) / 10000000ll);
 
    return 0;
}

Variable Documentation

dstflag_cache

int dstflag_cache = UNKNOWN_TIME

static

Definition at line 29 of file ftime.cpp.

Referenced by common_ftime_s().

elapsed_minutes_cache

__time64_t elapsed_minutes_cache = 0

static

Definition at line 17 of file ftime.cpp.

Referenced by common_ftime_s().