Linux 0.12ÄÚºË

2. linux/kernel/mktime.c
/*
 * PS. I hate whoever though up the year 1970 - couldn't they have gotten
 * a leap-year instead? I also hate Gregorius, pope or no. I'm grumpy.
 */
#define MINUTE 60
#define HOUR (60*MINUTE)
#define DAY (24*HOUR)
#define YEAR (365*DAY)                /*·ÇÈòÄêµÄÃëÊý*/
/* interestingly, we assume leap-years */
static int month[12] = {
             0,
             DAY*(31),
             DAY*(31+29),
             DAY*(31+29+31),
             DAY*(31+29+31+30),
             DAY*(31+29+31+30+31),
             DAY*(31+29+31+30+31+30),
             DAY*(31+29+31+30+31+30+31),
             DAY*(31+29+31+30+31+30+31+31),
             DAY*(31+29+31+30+31+30+31+31+30),
             DAY*(31+29+31+30+31+30+31+31+30+31),
             DAY*(31+29+31+30+31+30+31+31+30+31+30)
};
/*
 * Õâ¸öfunctionµÄ×÷ÓþÍÊÇ°ÑCMOSÖеĵ±Ç°Ê±¼äÖµtmת»»³É×Ô1970Äê1ÔÂ1ÈÕ0ʱ0·Ö0ÃëÖÁ½ñµÄÃëÊý£¬
 * ¼´Linux¿ª»úµÄʱ¼ä
 */
long kernel_mktime(struct tm * tm)
{
        long res;
        int year;
        year = tm->tm_year - 70; &