标签:const ges long linu linux内核 stdin midnight char pre
有些系统没有localtime和maketime, 把linux内核里边这两函数扣出来用。
#include <stdio.h> #include <string.h> #include <stdlib.h> #include <ctype.h> #include <stdint.h> struct tm { /* * the number of seconds after the minute, normally in the range * 0 to 59, but can be up to 60 to allow for leap seconds */ int tm_sec; /* the number of minutes after the hour, in the range 0 to 59*/ int tm_min; /* the number of hours past midnight, in the range 0 to 23 */ int tm_hour; /* the day of the month, in the range 1 to 31 */ int tm_mday; /* the number of months since January, in the range 0 to 11 */ int tm_mon; /* the number of years since 1900 */ long tm_year; /* the number of days since Sunday, in the range 0 to 6 */ int tm_wday; /* the number of days since January 1, in the range 0 to 365 */ int tm_yday; int tm_isdst; }; static unsigned long mktime(const unsigned int year0, const unsigned int mon0, const unsigned int day, const unsigned int hour, const unsigned int min, const unsigned int sec) { unsigned int mon = mon0, year = year0; /* 1..12 -> 11,12,1..10 */ if (0 >= (int) (mon -= 2)) { mon += 12; /* Puts Feb last since it has leap day */ year -= 1; } return ((((unsigned long) (year/4 - year/100 + year/400 + 367*mon/12 + day) + year*365 - 719499 )*24 + hour /* now have hours */ )*60 + min /* now have minutes */ )*60 + sec; /* finally seconds */ } static struct tm * localtime_r(time_t *srctime,struct tm *tm_time) { long int n32_Pass4year,n32_hpery; const static char Days[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; const static int ONE_YEAR_HOURS = 8760; time_t time = *srctime; time=time+28800; tm_time->tm_isdst=0; if(time < 0) { time = 0; } tm_time->tm_sec=(int)(time % 60); time /= 60; tm_time->tm_min=(int)(time % 60); time /= 60; tm_time->tm_wday=(time/24+4)%7; n32_Pass4year=((unsigned int)time / (1461L * 24L)); tm_time->tm_year=(n32_Pass4year << 2)+70; time %= 1461L * 24L; tm_time->tm_yday=(time/24)%365; for (;;) { n32_hpery = ONE_YEAR_HOURS; if ((tm_time->tm_year & 3) == 0) { n32_hpery += 24; } if (time < n32_hpery) { break; } tm_time->tm_year++; time -= n32_hpery; } tm_time->tm_hour=(int)(time % 24); time /= 24; time++; if ((tm_time->tm_year & 3) == 0) { if (time > 60) { time--; } else { if (time == 60) { tm_time->tm_mon = 1; tm_time->tm_mday = 29; return tm_time; } } } for (tm_time->tm_mon = 0;Days[tm_time->tm_mon] < time;tm_time->tm_mon++) { time -= Days[tm_time->tm_mon]; } tm_time->tm_mday = (int)(time); return tm_time; } int main(void) { uint32_t now = 1451577600; /*2016/01/01 00:00:00*/ struct tm tm = {0}; char *wday[] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}; localtime_r(&now, &tm); printf("%d/%d/%d \n", 1900 + tm.tm_year, 1 + tm.tm_mon, tm.tm_mday); printf("%s %d:%d:%d \n", wday[tm.tm_wday], tm.tm_hour, tm.tm_min, tm.tm_sec); now = mktime(1900 + tm.tm_year, 1 + tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec); printf("rtc value : %d\n", now); return 0; }
end
标签:const ges long linu linux内核 stdin midnight char pre
原文地址:http://www.cnblogs.com/dong1/p/6219801.html