使用Windows C中具有毫秒精度和分辨率的时间戳记录

我知道,对于计时准确性,timeGetTime,timeBeginPeriod,Query PerformanceCounter等功能都很棒,同时具有良好的分辨率和优点.准确性,但仅基于启动时间,没有与时钟时间的直接链接.

但是,我不想这样的时间事件.我希望能够生成一个确切的时间戳(本地时间),以便我可以在日志文件中显示它,例如31-12-2010 12：38：35.345,对于每个条目. (我需要毫秒精度)

标准的Windows时间函数,如GetLocalTime,虽然它们提供毫秒值,但没有毫秒级的分辨率,具体取决于运行的操作系统.我正在使用XP,所以我不能指望比大约15ms的分辨率好多了.

我需要的是一种获得两全其美的方法,而不会产生大量开销来获得所需的输出.过大的方法/计算意味着记录仪在其运行期间会开始耗费太多时间.

最好/最简单的方法是什么？

首先,一些功能：

// ==========================================================================
#define NOMINMAX
#define _AFXDLL
#include "afxwin.h"               // TRACE
#include "windows.h"              // ULARGE_INTEGER
#include "mmSystem.h"             // timeGetTime
#pragma comment(lib,"Winmm.lib") // timeGetTime

// ==========================================================================
// convert FILETIME to ULONGLONG
// (casting won't work on 64-bit platforms,due to alignment of FILETIME members)
inline void ToULL(const FILETIME& ft,ULONGLONG& uft)
{
    ULARGE_INTEGER uli;
    uli.LowPart = ft.dwLowDateTime ;
    uli.HighPart= ft.dwHighDateTime;
    uft= uli.QuadPart;
}

// --------------------------------------------------------------------------
// convert ULONGLONG to FILETIME
// (casting won't work on 64-bit platforms,due to alignment of FILETIME members)
inline void ToFILETIME(const ULONGLONG& uft,FILETIME& ft)
{
    ULARGE_INTEGER uli;
    uli.QuadPart= uft;
    ft.dwLowDateTime = uli.LowPart ;
    ft.dwHighDateTime= uli.HighPart;
}

// --------------------------------------------------------------------------
// ULONGLONG version for GetSystemTimeAsFileTime
inline void GetSystemTimeAsULL(ULONGLONG& uft)
{
    FILETIME ft;
    ::GetSystemTimeAsFileTime(&ft);
    ToULL(ft,uft);
}

// --------------------------------------------------------------------------
// convert ULONGLONG to time-components
bool ULLToSystemTime(const ULONGLONG nTime,// [i]
                     WORD&           nYear,// [o] 1601 - 30827
                     WORD&           nMonth,// [o] 1 -    12
                     WORD&           nDay,// [o] 1 -    31
                     WORD&           nHour,// [o] 0 -    23
                     WORD&           nMinute,// [o] 0 -    59
                     WORD&           nSecond,// [o] 0 -    59
                     WORD&           nMilliseconds ) // [o] 0 -   999
{
    SYstemTIME sysTime;
    FILETIME   ft     ;
    ToFILETIME(nTime,ft);

    // the wDayOfWeek member of the SYstemTIME structure is ignored
    if (0 == ::FileTimetoSystemTime(&ft,&sysTime))
        return false;

    nYear        = sysTime.wYear        ;
    nMonth       = sysTime.wMonth       ;
    nDay         = sysTime.wDay         ;
    nHour        = sysTime.wHour        ;
    nMinute      = sysTime.wMinute      ;
    nSecond      = sysTime.wSecond      ;
    nMilliseconds= sysTime.wMilliseconds;
    return true;
}

// --------------------------------------------------------------------------
void TraceTime(const ULONGLONG nTime) // [i]
{
    WORD nYear,nMonth,nDay,nHour,nMinute,nSecond,nMilliseconds;
    ULLToSystemTime(nTime,nYear,nMilliseconds);
    TRACE("Time: %02u-%02u-%04u %02u:%02u:%02u.%03u\n",nMilliseconds);
}

现在,如何使用：

ULONGLONG u0,u1;
::GetSystemTimeAsULL(u0);

// wait for tick (each 14.4mS)
do
{
    ::GetSystemTimeAsULL(u1);
}
while (u0==u1);

DWORD d1= ::timeGetTime();

// d1 and u1 are Now synchronized

// ... do some work

// get current time:
ULONGLONG u2= u1+(::timeGetTime() - d1)*10000; // mSec --> HectoNanoSec

TraceTime(u2);

请注意,您应该在2-3分钟内重新同步d1和u1一次,以保持准确性.实际上,您可以测量时钟之间的漂移,以找到最佳的重新同步间隔.

使用Windows C中具有毫秒精度和分辨率的时间戳记录

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