AstralTransRocketries/ClassiCube
1
0
Fork 0
mirror of https://github.com/ClassiCube/ClassiCube.git synced 2025-09-16 02:56:09 -04:00
Code Issues Packages Projects Releases Wiki Activity

Finally get DateTime_FromTotalMS right

Browse Source
This commit is contained in:
UnknownShadow200 2018-05-13 21:57:10 +10:00
parent 94795c876b
commit 6db245f9d8
1 changed files with 25 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
src/Client/Utils.c
View File

@ -10,6 +10,10 @@
#define DATETIME_HOURS_PER_DAY 24
#define DATETIME_MILLISECS_PER_DAY (1000 * 60 * 60 * 24)
#define DAYS_IN_400_YEARS 146097 /* (400*365) + 97 */
UInt16 DateTime_DaysTotal[13] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };
UInt16 DateTime_DaysTotalLeap[13] = { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 };
bool DateTime_IsLeapYear(Int32 year) {
if ((year % 4) != 0) return false;
if ((year % 100) != 0) return true;
@ -24,8 +28,7 @@ Int32 DateTime_TotalDays(DateTime* time) {
days += (y / 4) - (y / 100) + (y / 400);
/* Add days of prior months in this year */
static UInt16 totalDays[13] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 };
days += totalDays[time->Month - 1];
days += DateTime_DaysTotal[time->Month - 1];
/* Add Feb 29, if this is a leap year, and day of point in time is after Feb 28 */
if (DateTime_IsLeapYear(time->Year) && time->Month > 2) days++;
/* Add days in this month */
@ -59,15 +62,28 @@ void DateTime_FromTotalMs(DateTime* time, Int64 ms) {
time->Hour = dayMS % DATETIME_HOURS_PER_DAY; dayMS /= DATETIME_HOURS_PER_DAY;
/* Then work out day/month/year component (inverse TotalDays operation) */
/* Probably not the most efficient way of doing this. But it passes my tests at */
/* https://gist.github.com/UnknownShadow200/30993c66464bb03ead01577f3ab2a653 */
Int32 days = ms / (Int64)DATETIME_MILLISECS_PER_DAY;
time->Year = 1 + days * 400 / 146097;
// nope, this is wrong!
Int32 year = 1 + ((days / DAYS_IN_400_YEARS) * 400); days %= DAYS_IN_400_YEARS;
bool leap;
/* Days in just this year */
time->Month = 1; time->Day = 1;
days -= DateTime_TotalDays(time);
/* TOOD: black magic here */
sddssdfds
for (; ; year++) {
leap = DateTime_IsLeapYear(year);
Int32 daysInYear = leap ? 366 : 365;
if (days < daysInYear) break;
days -= daysInYear;
}
time->Year = year;
UInt16* totalDays = leap ? DateTime_DaysTotalLeap : DateTime_DaysTotal;
Int32 i;
for (i = 1; i <= 12; i++) {
if (days >= totalDays[i]) continue;
time->Month = i;
time->Day = 1 + (days - totalDays[i - 1]);
return;
}
}
void DateTime_HttpDate(DateTime* value, STRING_TRANSIENT String* str) {