我的unix-epoch时间转换器出现问题

时间:2013-04-03 20:36:37

标签: c unix-timestamp

我写了一个简单的函数来填充当前年,月和日的三个变量。 但是,由于某种原因,它无法正常工作,我似乎无法找到问题。

void getDate(int *year, int *month, int *date)
{
int   epochTime,
      monthLength,
      functionYear,
      functionMonth,
      functionDate;

functionYear   = 1970;
functionMonth  = 1;
functionDate   = 1;

epochTime = time(NULL);
while (epochTime > 1 * 365 * 24 * 60 * 60)
{
   epochTime -= 1 * 365 * 24 * 60 * 60;
   functionYear++;
}
monthLength = findMonthLength(functionYear, functionMonth, false);
while (epochTime > 1 * monthLength * 24 * 60 * 60)
{
   printf("%d\n", epochTime);
   epochTime -= 1 * monthLength * 24 * 60 * 60;
   functionMonth++;
   monthLength = findMonthLength(functionYear, functionMonth, false);      
   printf("functionMonth = %d\n", functionMonth);
}
while (epochTime > 1 * 24 * 60 * 60)
{
   printf("%d\n", epochTime);
   epochTime -= 1 * 24 * 60 * 60;
   functionDate++;
   printf("functionDate = %d\n", functionDate);
}
*year    = functionYear;
*month   = functionMonth;
*date    = functionDate;
}

findMonthLength()返回一个整数值,该值是发送月份的长度。 1 = 1月等。它使用年份来测试它是否是闰年。

目前是2013年4月3日;但是,我的功能发现4月15日,我似乎无法找到我的问题所在。

编辑: 我知道了。我的第一个问题是,当我记得在找到月份的时候检查闰年时,我忘记了每年找到的时间,这让我休息了好几天。 我的第二个问题是我没有从UTC转换到当地时区

3 个答案:

答案 0 :(得分:2)

本节可能存在一个问题:

while (epochTime > 1 * 365 * 24 * 60 * 60)
{
    epochTime -= 1 * 365 * 24 * 60 * 60;
    functionYear++;
} 

此循环的每次迭代,减去对应于一个正常年的以秒为单位的时间。这不考虑闰年,您需要减去相当于366天的时间。

对于该部分,您可能需要:

int yearLength = findYearLength(functionYear + 1);
while (epochTime > 1 * yearLength * 24 * 60 * 60)
{
    epochTime -= 1 * yearLength * 24 * 60 * 60;
    functionYear++;
    yearLength = findYearLength(functionYear + 1);
}

使用 findYearLength(int year)是一个返回给定年份的天数的函数。

一个小问题是没有考虑leap seconds。由于只添加了其中的35个,因此可以在给定日期的计算中安全地忽略该值。

答案 1 :(得分:1)

为什么不使用gmtime()或localtime()并完成它?它们返回一个包含您需要的所有内容的结构。

答案 2 :(得分:0)

我用Python制作了完整的解决方案。我希望有一天能帮助某人。干杯!

使用:getDate(unixtime)

def leapYear(year):
        #returns True if the year is a leap year, return False if it isn't
        if year % 400 == 0:
                return True
        elif year % 100 == 0:
                return False
        elif year % 4 == 0: 
                return True
        else:
             return False

def findMonthLength(year, month):
        #returns an integer value with the length of the month it is sent.
        #1 = January, etc. It uses the year to test if it is a leap year.

        months1 = [0,31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
        months2 = [0,31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

        if (leapYear(year)==True):
                return months2[month]
        else:
                return months1[month]

def findYearLength(year):
        #returns an integer value with the length of the year it is sent.
        #It uses the year to test if it is a leap year.

        if leapYear(year)==True:
                return 366
        else:
                return 365

def getDate(epoch):
        SECONDS_PER_YEAR = 0
        SECONDS_PER_MONTH = 0
        SECONDS_PER_DAY = 24 * 60 * 60
        SECONDS_PER_HOUR = 60*60
        SECONDS_PER_MIN = 60

        epochTime = epoch
        monthLength = 0
        yearLength = 0
        year = 1970
        month = 1
        day = 1
        hour = 0
        minu = 0
        seg = 0

        #Years
        yearLength = findYearLength(year)
        SECONDS_PER_YEAR = yearLength * SECONDS_PER_DAY
        while (epochTime >= SECONDS_PER_YEAR):
                epochTime -= SECONDS_PER_YEAR
                year += 1
                yearLength = findYearLength(year)
                SECONDS_PER_YEAR = yearLength * SECONDS_PER_DAY

        #Months
        monthLength = findMonthLength(year, month)
        SECONDS_PER_MONTH = monthLength * SECONDS_PER_DAY
        while (epochTime >= SECONDS_PER_MONTH):
                epochTime -= SECONDS_PER_MONTH;
                month += 1
                monthLength = findMonthLength(year, month)
                SECONDS_PER_MONTH = monthLength * SECONDS_PER_DAY

        #Days
        while (epochTime >= SECONDS_PER_DAY):
                epochTime -= SECONDS_PER_DAY;
                day += 1

        #Hours
        while (epochTime >= SECONDS_PER_HOUR):
                epochTime -= SECONDS_PER_HOUR;
                hour += 1

        #Minutes
        while (epochTime >= SECONDS_PER_MIN):
                epochTime -= SECONDS_PER_MIN;
                minu += 1

        #Seconds
        seg = epochTime

        print ("%d-%d-%d %d:%d:%d") % (year, month, day, hour, minu, seg)