use super::Tm;
use std::io;
use std::mem;
use windows_sys::Win32::Foundation::{FILETIME, SYSTEMTIME};
use windows_sys::Win32::System::Time::{GetTimeZoneInformation, SystemTimeToFileTime};
use windows_sys::Win32::System::Time::FileTimeToSystemTime;
use windows_sys::Win32::System::Time::SystemTimeToTzSpecificLocalTime;
use windows_sys::Win32::System::Time::TzSpecificLocalTimeToSystemTime;
const HECTONANOSECS_IN_SEC: i64 = 10_000_000;
const HECTONANOSEC_TO_UNIX_EPOCH: i64 = 11_644_473_600 * HECTONANOSECS_IN_SEC;
fn time_to_file_time(sec: i64) -> FILETIME {
let t = ((sec * HECTONANOSECS_IN_SEC) + HECTONANOSEC_TO_UNIX_EPOCH) as u64;
FILETIME {
dwLowDateTime: t as u32,
dwHighDateTime: (t >> 32) as u32,
}
}
fn file_time_as_u64(ft: &FILETIME) -> u64 {
((ft.dwHighDateTime as u64) << 32) | (ft.dwLowDateTime as u64)
}
fn file_time_to_unix_seconds(ft: &FILETIME) -> i64 {
let t = file_time_as_u64(ft) as i64;
((t - HECTONANOSEC_TO_UNIX_EPOCH) / HECTONANOSECS_IN_SEC) as i64
}
fn system_time_to_file_time(sys: &SYSTEMTIME) -> FILETIME {
unsafe {
let mut ft = mem::zeroed();
SystemTimeToFileTime(sys, &mut ft);
ft
}
}
fn tm_to_system_time(tm: &Tm) -> SYSTEMTIME {
let mut sys: SYSTEMTIME = unsafe { mem::zeroed() };
sys.wSecond = tm.tm_sec as u16;
sys.wMinute = tm.tm_min as u16;
sys.wHour = tm.tm_hour as u16;
sys.wDay = tm.tm_mday as u16;
sys.wDayOfWeek = tm.tm_wday as u16;
sys.wMonth = (tm.tm_mon + 1) as u16;
sys.wYear = (tm.tm_year + 1900) as u16;
sys
}
fn system_time_to_tm(sys: &SYSTEMTIME, tm: &mut Tm) {
tm.tm_sec = sys.wSecond as i32;
tm.tm_min = sys.wMinute as i32;
tm.tm_hour = sys.wHour as i32;
tm.tm_mday = sys.wDay as i32;
tm.tm_wday = sys.wDayOfWeek as i32;
tm.tm_mon = (sys.wMonth - 1) as i32;
tm.tm_year = (sys.wYear - 1900) as i32;
tm.tm_yday = yday(tm.tm_year, tm.tm_mon + 1, tm.tm_mday);
fn yday(year: i32, month: i32, day: i32) -> i32 {
let leap = if month > 2 {
if year % 4 == 0 {
1
} else {
2
}
} else {
0
};
let july = if month > 7 { 1 } else { 0 };
(month - 1) * 30 + month / 2 + (day - 1) - leap + july
}
}
macro_rules! call {
($name:ident($($arg:expr),*)) => {
if $name($($arg),*) == 0 {
panic!(concat!(stringify!($name), " failed with: {}"),
io::Error::last_os_error());
}
}
}
pub fn time_to_local_tm(sec: i64, tm: &mut Tm) {
let ft = time_to_file_time(sec);
unsafe {
let mut utc = mem::zeroed();
let mut local = mem::zeroed();
call!(FileTimeToSystemTime(&ft, &mut utc));
call!(SystemTimeToTzSpecificLocalTime(
0 as *const _,
&mut utc,
&mut local
));
system_time_to_tm(&local, tm);
let local = system_time_to_file_time(&local);
let local_sec = file_time_to_unix_seconds(&local);
let mut tz = mem::zeroed();
GetTimeZoneInformation(&mut tz);
// SystemTimeToTzSpecificLocalTime already applied the biases so
// check if it non standard
tm.tm_utcoff = (local_sec - sec) as i32;
tm.tm_isdst = if tm.tm_utcoff == -60 * (tz.Bias + tz.StandardBias) {
0
} else {
1
};
}
}
pub fn utc_tm_to_time(tm: &Tm) -> i64 {
unsafe {
let mut ft = mem::zeroed();
let sys_time = tm_to_system_time(tm);
call!(SystemTimeToFileTime(&sys_time, &mut ft));
file_time_to_unix_seconds(&ft)
}
}
pub fn local_tm_to_time(tm: &Tm) -> i64 {
unsafe {
let mut ft = mem::zeroed();
let mut utc = mem::zeroed();
let mut sys_time = tm_to_system_time(tm);
call!(TzSpecificLocalTimeToSystemTime(
0 as *mut _,
&mut sys_time,
&mut utc
));
call!(SystemTimeToFileTime(&utc, &mut ft));
file_time_to_unix_seconds(&ft)
}
}