浅谈时间戳与日期时间互转C语言

/*
 * ctime.h
 *
 * Created on: May 19, 2016
 *    
*/
 
#ifndef CTIME_H_
#define CTIME_H_
#include "common/micro_type.h"
#define OFFSET_SECOND   946684800 /* ��1970/1/1/0/0/0��2000/1/1/0/0/0֮��������� */
//#define OFFSET_SECOND  0     /* ��2000/1/1/0/0/0��2000/1/1/0/0/0֮��������� */
#define SECOND_OF_DAY   86400   /* 1�������                   */
 
typedef struct date_time
{
  uint16  iYear;
  uint16  iMon;
  uint16  iDay;
 
  uint16  iHour;
  uint16  iMin;
  uint16  iSec;
  uint16  iMsec;
} DATE_TIME;
 
void GetDateTimeFromSecond(unsigned long lSec, DATE_TIME *tTime);
#endif /* CTIME_H_ */
 

/*
 * ctime.c
 *
 * Created on: May 19, 2016
 *   Author: root
 */
#include "common/micro_type.h"
#include "ctime.h"
uint8 DayOfMon[12] = {31,28,31,30,31,30,31,31,30,31,30,31};
 
/* ������1970/1/1/0/0/0�����ʱ */
unsigned long GetSecondTime(DATE_TIME *date_time)
{
  uint16 iYear, iMon, iDay, iHour, iMin, iSec;
  iYear = date_time->iYear;
  iMon = date_time->iMon;
  iDay = date_time->iDay;
  iHour = date_time->iHour;
  iMin = date_time->iMin;
  iSec = date_time->iSec;
 
  uint16 i, Cyear=0;
  unsigned long CountDay=0;
 
  for(i=1970; i<iYear; i++)   /* ͳ��1970�굽����֮ǰ�������� */
  {
    if(((i%4==0) && (i%100!=0)) || (i%400==0)) Cyear++;
  }
  CountDay = Cyear * 366 + (iYear-1970-Cyear) * 365;
  for(i=1; i<iMon; i++)
  {
    if((i==2) && (((iYear%4==0)&&(iYear%100!=0)) || (iYear%400==0)))
      CountDay += 29;
    else
      CountDay += DayOfMon[i-1];
  }
  CountDay += (iDay-1);
 
  CountDay = CountDay*SECOND_OF_DAY + (unsigned long)iHour*3600 + (unsigned long)iMin*60 + iSec;
  return CountDay;
}
 
/* ����ʱ�������1970/1/1/0/0������ */
void GetDateTimeFromSecond(unsigned long lSec, DATE_TIME *tTime)
{
  uint16 i,j,iDay;
  unsigned long lDay;
 
  lDay = lSec / SECOND_OF_DAY;    /* תΪ�������ʱ�� */
  lSec = lSec % SECOND_OF_DAY;
 
  i = 1970;
  while(lDay > 365)
  {
   if(((i%4==0)&&(i%100!=0)) || (i%400==0))  /* ���� */
    lDay -= 366;
   else
    lDay -= 365;
   i++;
  }
  if((lDay == 365) && !(((i%4==0)&&(i%100!=0)) || (i%400==0))) /* ƽ�� */
  {
   lDay -= 365;
   i++;
  }
  tTime->iYear = i;   /* �õ���� */
  for(j=0;j<12;j++)   /* �����?� */
  {
   if((j==1) && (((i%4==0)&&(i%100!=0)) || (i%400==0)))
    iDay = 29;
   else
    iDay = DayOfMon[j];
   if(lDay >= iDay) lDay -= iDay;
   else break;
  }
  tTime->iMon = j+1;
  tTime->iDay = lDay+1;
  tTime->iHour = ((lSec / 3600)+8)%24;//这里注意，世界时间已经加上北京时间差8，
  tTime->iMin = (lSec % 3600) / 60;
  tTime->iSec = (lSec % 3600) % 60;
}