beenull/ladybird
1
0
Fork 0
mirror of https://github.com/LadybirdBrowser/ladybird.git synced 2024-11-21 23:20:20 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

AK+LibC+Kernel: Have fewer implementations of year_to_days_in_epoch

Browse source 
I believe the implementation in RTC.cpp had an off-by-one
in the year passed to is_leap_year(). If that's true, then this
fixes that too.
This commit is contained in:
Nico Weber 2020-08-25 16:53:36 -04:00 committed by Andreas Kling
parent 84ed257959
commit 9b17082899
Notes: sideshowbarker 2024-07-19 03:08:47 +09:00 
Author: https://github.com/nico
Commit: https://github.com/SerenityOS/serenity/commit/9b170828999
Pull-request: https://github.com/SerenityOS/serenity/pull/3307
3 changed files with 13 additions and 18 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
AK/Time.h
View file

@ -33,6 +33,16 @@ inline bool is_leap_year(int year)
return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
}
inline int years_to_days_since_epoch(int year)
{
int days = 0;
for (int current_year = 1970; current_year < year; ++current_year)
days += 365 + is_leap_year(current_year);
for (int current_year = year; current_year < 1970; ++current_year)
days -= 365 + is_leap_year(current_year);
return days;
}
template<typename TimevalType>
inline void timeval_sub(const TimevalType& a, const TimevalType& b, TimevalType& result)
{
@ -160,6 +170,7 @@ using AK::timespec_to_timeval;
using AK::timeval_add;
using AK::timeval_sub;
using AK::timeval_to_timespec;
using AK::years_to_days_since_epoch;
using AK::operator<=;
using AK::operator<;
using AK::operator>;

14
Kernel/RTC.cpp
View file

@ -93,18 +93,6 @@ static unsigned days_in_months_since_start_of_year(unsigned month, unsigned year
return days;
}
static unsigned days_in_years_since_epoch(unsigned year)
{
unsigned days = 0;
while (year > 1969) {
days += 365;
if (is_leap_year(year))
++days;
--year;
}
return days;
}
static u8 bcd_to_binary(u8 bcd)
{
return (bcd & 0x0F) + ((bcd >> 4) * 10);
@ -160,7 +148,7 @@ time_t now()
ASSERT(year >= 2018);
return days_in_years_since_epoch(year - 1) * 86400
return years_to_days_since_epoch(year) * 86400
+ days_in_months_since_start_of_year(month - 1, year) * 86400
+ (day - 1) * 86400
+ hour * 3600

6
Libraries/LibC/time.cpp
View file

@ -116,11 +116,7 @@ static time_t tm_to_time(struct tm* tm, long timezone_adjust_seconds)
tm->tm_mon += 12;
}
int days = 0;
for (int year = 70; year < tm->tm_year; ++year)
days += 365 + is_leap_year(1900 + year);
for (int year = tm->tm_year; year < 70; ++year)
days -= 365 + is_leap_year(1900 + year);
int days = years_to_days_since_epoch(1900 + tm->tm_year);
tm->tm_yday = tm->tm_mday - 1;
for (int month = 0; month < tm->tm_mon; ++month)