reactos/sdk/lib/crt/time/mktime.c

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/*
* COPYRIGHT: LGPL, See LGPL.txt in the top level directory
* PROJECT: ReactOS CRT library
* FILE: lib/sdk/crt/time/mktime.c
* PURPOSE: Implementation of mktime, _mkgmtime
* PROGRAMERS: Timo Kreuzer
*/
#include <precomp.h>
#include "bitsfixup.h"
#define MAX_32BIT_TIME 0xFFFFFFFFULL
static int g_monthdays[13] = {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365};
__time64_t
mktime_worker(struct tm * ptm, int utc)
{
struct tm *ptm2;
__time64_t time;
int mons, years, leapyears;
TIME_ZONE_INFORMATION tzi;
DWORD ret;
/* Normalize year and month */
if (ptm->tm_mon < 0)
{
mons = -ptm->tm_mon - 1;
ptm->tm_year -= 1 + mons / 12;
ptm->tm_mon = 11 - (mons % 12);
}
else if (ptm->tm_mon > 11)
{
mons = ptm->tm_mon;
ptm->tm_year += (mons / 12);
ptm->tm_mon = mons % 12;
}
/* Is it inside margins */
if (ptm->tm_year < 70 || ptm->tm_year > 139) // FIXME: max year for 64 bits
{
return -1;
}
years = ptm->tm_year - 70;
/* Number of leapyears passed since 1970 */
leapyears = (years + 1) / 4;
/* Calculate days up to 1st of Jan */
time = years * 365 + leapyears;
/* Calculate days up to 1st of month */
time += g_monthdays[ptm->tm_mon];
/* Check if we need to add a leap day */
if (((years + 2) % 4) == 0)
{
if (ptm->tm_mon > 2)
{
time++;
}
}
time += ptm->tm_mday - 1;
time *= 24;
time += ptm->tm_hour;
time *= 60;
time += ptm->tm_min;
time *= 60;
time += ptm->tm_sec;
if (time < 0)
{
return -1;
}
/* Finally get normalized tm struct */
ptm2 = _gmtime64(&time);
if (!ptm2)
{
return -1;
}
*ptm = *ptm2;
/* Finally adjust by the difference to GMT in seconds */
ret = GetTimeZoneInformation(&tzi);
if (ret != TIME_ZONE_ID_INVALID)
{
time += tzi.Bias * 60;
}
return time;
}
/* int tm_sec;
int tm_min;
int tm_hour;
int tm_mday;
int tm_mon;
int tm_year;
int tm_wday;
int tm_yday;
int tm_isdst;
*/
/**
* \name _mkgmtime
*
*/
time_t
_mkgmtime(struct tm *ptm)
{
__time64_t time = mktime_worker(ptm, 1);
return (time_t)((time > MAX_32BIT_TIME) ? -1 : time);
}
time_t
mktime(struct tm *ptm)
{
__time64_t time = mktime_worker(ptm, 0);
return (time_t)((time > MAX_32BIT_TIME) ? -1 : time);
}
__time32_t
_mkgmtime32(struct tm *ptm)
{
__time64_t time = mktime_worker(ptm, 1);
return (__time32_t)((time > MAX_32BIT_TIME) ? -1 : time);
}
__time32_t
_mktime32(struct tm *ptm)
{
__time64_t time = mktime_worker(ptm, 0);
return (__time32_t)((time > MAX_32BIT_TIME) ? -1 : time);
}
__time64_t
_mkgmtime64(struct tm *ptm)
{
return mktime_worker(ptm, 1);
}
__time64_t
_mktime64(struct tm *ptm)
{
return mktime_worker(ptm, 0);
}