C++ (Cpp) TM_TO_YMD示例

示例#1

文件： DateTime.cpp 项目： liminzhu/ChakraCore

static void YMDLocalToUtc(YMD *local, YMD *utc)
{
    struct tm local_tm;
    bool leap_added;
    YMD_TO_TM(local, (&local_tm), &leap_added);

    // tm doesn't have milliseconds
    int milliseconds = local->time % 1000;

    tzset();
    time_t utime = timegm(&local_tm);

    // mktime min year is 1900
    if (local_tm.tm_year < 1900)
    {
        local_tm.tm_year = 1900;
    }
    mktime(&local_tm);
    utime -= local_tm.tm_gmtoff;

    struct tm utc_tm;
    if (gmtime_r(&utime, &utc_tm) == 0)
    {
        AssertMsg(false, "gmtime() failed");
    }

    TM_TO_YMD((&utc_tm), utc, leap_added, local->year);
    // put milliseconds back
    utc->time += milliseconds;
}

示例#2

文件： DateTime.cpp 项目： liminzhu/ChakraCore

static void YMDUtcToLocal(YMD *utc, YMD *local,
                          int &bias, int &offset, bool &isDaylightSavings)
{
    struct tm utc_tm;
    bool leap_added;
    YMD_TO_TM(utc, &utc_tm, &leap_added);

    // tm doesn't have milliseconds
    int milliseconds = utc->time % 1000;

    tzset();
    time_t ltime = timegm(&utc_tm);
    struct tm local_tm;
    localtime_r(&ltime, &local_tm);

    TM_TO_YMD((&local_tm), local, leap_added, utc->year);
    // put milliseconds back
    local->time += milliseconds;

    // ugly hack but;
    // right in between dst pass
    // we need mktime trick to get the correct dst
    utc_tm.tm_isdst = 1;
    ltime = mktime(&utc_tm);
    ltime += utc_tm.tm_gmtoff;
    localtime_r(&ltime, &utc_tm);

    isDaylightSavings = utc_tm.tm_isdst;
    offset = utc_tm.tm_gmtoff / 60;
    bias = offset;
}

示例#3

文件： DateTime.cpp 项目： dilijev/ChakraCore

static void YMDLocalToUtc(YMD *local, YMD *utc)
{
    struct tm local_tm;
    bool leap_added;
    YMD_TO_TM(local, (&local_tm), &leap_added);

    // tm doesn't have milliseconds
    int milliseconds = local->time % 1000;

    tzset();
    time_t utime = timegm(&local_tm);

    // we alter the original date
    // and mktime doesn't know that
    // so calculate gmtoff manually and keep dst from being included
    mktime(&local_tm);
    utime -= local_tm.tm_gmtoff;

    struct tm utc_tm;
    if (gmtime_r(&utime, &utc_tm) == 0)
    {
        AssertMsg(false, "gmtime() failed");
    }

    TM_TO_YMD((&utc_tm), utc, leap_added, local->year);
    // put milliseconds back
    utc->time += milliseconds;
}