Refactor windows module in Local

src/datetime/tests.rs

@@ -950,3 +950,38 @@ fn test_datetime_sub_assign_local() {
         assert_eq!(datetime_sub, datetime - Duration::days(i))
     }
 }
+
+#[test]
+#[cfg(target_os = "windows")]
+fn test_from_naive_date_time_windows() {
+    let min_year = NaiveDate::from_ymd_opt(1601, 1, 3).unwrap().and_hms_opt(0, 0, 0).unwrap();
+
+    let max_year = NaiveDate::from_ymd_opt(30827, 12, 29).unwrap().and_hms_opt(23, 59, 59).unwrap();
+
+    let too_low_year =
+        NaiveDate::from_ymd_opt(1600, 12, 29).unwrap().and_hms_opt(23, 59, 59).unwrap();
+
+    let too_high_year = NaiveDate::from_ymd_opt(30829, 1, 3).unwrap().and_hms_opt(0, 0, 0).unwrap();
+
+    let _ = Local.from_utc_datetime(&min_year);
+    let _ = Local.from_utc_datetime(&max_year);
+
+    let _ = Local.from_local_datetime(&min_year);
+    let _ = Local.from_local_datetime(&max_year);
+
+    let local_too_low = Local.from_local_datetime(&too_low_year);
+    let local_too_high = Local.from_local_datetime(&too_high_year);
+
+    assert_eq!(local_too_low, LocalResult::None);
+    assert_eq!(local_too_high, LocalResult::None);
+
+    let err = std::panic::catch_unwind(|| {
+        Local.from_utc_datetime(&too_low_year);
+    });
+    assert!(err.is_err());
+
+    let err = std::panic::catch_unwind(|| {
+        Local.from_utc_datetime(&too_high_year);
+    });
+    assert!(err.is_err());
+}

src/format/scan.rs

@@ -48,7 +48,7 @@ pub(super) fn number(s: &str, min: usize, max: usize) -> ParseResult<(&str, i64)
     let mut n = 0i64;
     for (i, c) in bytes.iter().take(max).cloned().enumerate() {
         // cloned() = copied()
-        if !(b'0'..=b'9').contains(&c) {
+        if !c.is_ascii_digit() {
             if i < min {
                 return Err(INVALID);
             } else {
@@ -79,7 +79,7 @@ pub(super) fn nanosecond(s: &str) -> ParseResult<(&str, i64)> {
     let v = v.checked_mul(SCALE[consumed]).ok_or(OUT_OF_RANGE)?;
 
     // if there are more than 9 digits, skip next digits.
-    let s = s.trim_left_matches(|c: char| ('0'..='9').contains(&c));
+    let s = s.trim_left_matches(|c: char| c.is_ascii_digit());
 
     Ok((s, v))
 }

src/offset/local/mod.rs

@@ -34,6 +34,9 @@ mod inner;
 #[path = "windows.rs"]
 mod inner;
 
+#[cfg(windows)]
+mod windows_sys;
+
 #[cfg(unix)]
 mod tz_info;
 

src/offset/local/windows.rs

@@ -8,271 +8,105 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use std::io;
-use std::mem;
+use std::io::Error;
+use std::result::Result;
 use std::time::{SystemTime, UNIX_EPOCH};
 
-use winapi::shared::minwindef::*;
-use winapi::um::minwinbase::SYSTEMTIME;
-use winapi::um::timezoneapi::*;
+use super::windows_sys::WinSystemTime;
 
 use super::{FixedOffset, Local};
-use crate::{DateTime, Datelike, LocalResult, NaiveDate, NaiveDateTime, NaiveTime, Timelike};
+use crate::{DateTime, LocalResult, NaiveDate, NaiveDateTime, NaiveTime, Timelike};
 
 pub(super) fn now() -> DateTime<Local> {
-    tm_to_datetime(Timespec::now().local())
+    InnerDuration::now_locally().datetime()
 }
 
 /// Converts a local `NaiveDateTime` to the `time::Timespec`.
 pub(super) fn naive_to_local(d: &NaiveDateTime, local: bool) -> LocalResult<DateTime<Local>> {
-    let tm = Tm {
-        tm_sec: d.second() as i32,
-        tm_min: d.minute() as i32,
-        tm_hour: d.hour() as i32,
-        tm_mday: d.day() as i32,
-        tm_mon: d.month0() as i32, // yes, C is that strange...
-        tm_year: d.year() - 1900,  // this doesn't underflow, we know that d is `NaiveDateTime`.
-        tm_wday: 0,                // to_local ignores this
-        tm_yday: 0,                // and this
-        tm_isdst: -1,
-        // This seems pretty fake?
-        tm_utcoff: if local { 1 } else { 0 },
-        // do not set this, OS APIs are heavily inconsistent in terms of leap second handling
-        tm_nsec: 0,
-    };
+    let naive_sys_time = WinSystemTime::from_naive_datetime(d);
 
-    let spec = Timespec {
-        sec: match local {
-            false => utc_tm_to_time(&tm),
-            true => local_tm_to_time(&tm),
-        },
-        nsec: tm.tm_nsec,
+    let local_sys_time = match local {
+        false => LocalSysTime::from_utc_time(naive_sys_time),
+        true => LocalSysTime::from_local_time(naive_sys_time),
     };
 
-    // Adjust for leap seconds
-    let mut tm = spec.local();
-    assert_eq!(tm.tm_nsec, 0);
-    tm.tm_nsec = d.nanosecond() as i32;
-
-    // #TODO - there should be ambiguous cases, investigate?
-    LocalResult::Single(tm_to_datetime(tm))
-}
+    if let Ok(mut local) = local_sys_time {
+        assert_eq!(local.nsecs, 0);
+        local.set_nsecs(d.nanosecond() as i32);
 
-/// Converts a `time::Tm` struct into the timezone-aware `DateTime`.
-fn tm_to_datetime(mut tm: Tm) -> DateTime<Local> {
-    if tm.tm_sec >= 60 {
-        tm.tm_nsec += (tm.tm_sec - 59) * 1_000_000_000;
-        tm.tm_sec = 59;
+        return LocalResult::Single(local.datetime());
     }
 
-    let date = NaiveDate::from_ymd_opt(tm.tm_year + 1900, tm.tm_mon as u32 + 1, tm.tm_mday as u32)
-        .unwrap();
-    let time = NaiveTime::from_hms_nano(
-        tm.tm_hour as u32,
-        tm.tm_min as u32,
-        tm.tm_sec as u32,
-        tm.tm_nsec as u32,
-    );
-
-    let offset = FixedOffset::east_opt(tm.tm_utcoff).unwrap();
-    DateTime::from_utc(date.and_time(time) - offset, offset)
+    LocalResult::None
 }
 
-/// A record specifying a time value in seconds and nanoseconds, where
-/// nanoseconds represent the offset from the given second.
-///
-/// For example a timespec of 1.2 seconds after the beginning of the epoch would
-/// be represented as {sec: 1, nsec: 200000000}.
-struct Timespec {
+struct InnerDuration {
     sec: i64,
     nsec: i32,
 }
 
-impl Timespec {
+impl InnerDuration {
+    /// Constructs a new LocalSysTime representing the current time in UTC
     /// Constructs a timespec representing the current time in UTC.
-    fn now() -> Timespec {
+    fn now_locally() -> LocalSysTime {
         let st =
             SystemTime::now().duration_since(UNIX_EPOCH).expect("system time before Unix epoch");
-        Timespec { sec: st.as_secs() as i64, nsec: st.subsec_nanos() as i32 }
+        let now_duration = Self { sec: st.as_secs() as i64, nsec: st.subsec_nanos() as i32 };
+        LocalSysTime::from_duration(now_duration)
+            .expect("Now should not fail to produce a local sys time")
     }
 
-    /// Converts this timespec into the system's local time.
-    fn local(self) -> Tm {
-        let mut tm = Tm {
-            tm_sec: 0,
-            tm_min: 0,
-            tm_hour: 0,
-            tm_mday: 0,
-            tm_mon: 0,
-            tm_year: 0,
-            tm_wday: 0,
-            tm_yday: 0,
-            tm_isdst: 0,
-            tm_utcoff: 0,
-            tm_nsec: 0,
-        };
-        time_to_local_tm(self.sec, &mut tm);
-        tm.tm_nsec = self.nsec;
-        tm
+    fn from_seconds(sec: i64) -> Self {
+        Self { sec, nsec: 0 }
     }
 }
 
-/// Holds a calendar date and time broken down into its components (year, month,
-/// day, and so on), also called a broken-down time value.
-// FIXME: use c_int instead of i32?
-#[repr(C)]
-struct Tm {
-    /// Seconds after the minute - [0, 60]
-    tm_sec: i32,
-
-    /// Minutes after the hour - [0, 59]
-    tm_min: i32,
-
-    /// Hours after midnight - [0, 23]
-    tm_hour: i32,
-
-    /// Day of the month - [1, 31]
-    tm_mday: i32,
-
-    /// Months since January - [0, 11]
-    tm_mon: i32,
-
-    /// Years since 1900
-    tm_year: i32,
-
-    /// Days since Sunday - [0, 6]. 0 = Sunday, 1 = Monday, ..., 6 = Saturday.
-    tm_wday: i32,
-
-    /// Days since January 1 - [0, 365]
-    tm_yday: i32,
-
-    /// Daylight Saving Time flag.
-    ///
-    /// This value is positive if Daylight Saving Time is in effect, zero if
-    /// Daylight Saving Time is not in effect, and negative if this information
-    /// is not available.
-    tm_isdst: i32,
-
-    /// Identifies the time zone that was used to compute this broken-down time
-    /// value, including any adjustment for Daylight Saving Time. This is the
-    /// number of seconds east of UTC. For example, for U.S. Pacific Daylight
-    /// Time, the value is `-7*60*60 = -25200`.
-    tm_utcoff: i32,
-
-    /// Nanoseconds after the second - [0, 10<sup>9</sup> - 1]
-    tm_nsec: i32,
+struct LocalSysTime {
+    inner: WinSystemTime,
+    offset: i32,
+    nsecs: i32,
 }
 
-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 DWORD, dwHighDateTime: (t >> 32) as DWORD }
-}
+impl LocalSysTime {
+    pub(crate) fn from_duration(dur: InnerDuration) -> Result<Self, Error> {
+        let utc_sys_time = WinSystemTime::from_unix_seconds(dur.sec)?;
 
-fn file_time_as_u64(ft: &FILETIME) -> u64 {
-    ((ft.dwHighDateTime as u64) << 32) | (ft.dwLowDateTime as u64)
-}
+        let local_sys_time = utc_sys_time.as_time_zone_specific()?;
+        let local_secs = local_sys_time.as_unix_seconds()?;
 
-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
-}
+        let offset = (local_secs - dur.sec) as i32;
 
-fn system_time_to_file_time(sys: &SYSTEMTIME) -> FILETIME {
-    unsafe {
-        let mut ft = mem::zeroed();
-        SystemTimeToFileTime(sys, &mut ft);
-        ft
+        Ok(Self { inner: local_sys_time, offset, nsecs: dur.nsec })
     }
-}
-
-fn tm_to_system_time(tm: &Tm) -> SYSTEMTIME {
-    let mut sys: SYSTEMTIME = unsafe { mem::zeroed() };
-    sys.wSecond = tm.tm_sec as WORD;
-    sys.wMinute = tm.tm_min as WORD;
-    sys.wHour = tm.tm_hour as WORD;
-    sys.wDay = tm.tm_mday as WORD;
-    sys.wDayOfWeek = tm.tm_wday as WORD;
-    sys.wMonth = (tm.tm_mon + 1) as WORD;
-    sys.wYear = (tm.tm_year + 1900) as WORD;
-    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
+    fn from_utc_time(utc_time: WinSystemTime) -> Result<Self, Error> {
+        let duration = InnerDuration::from_seconds(utc_time.as_unix_seconds()?);
+        Self::from_duration(duration)
     }
-}
 
-macro_rules! call {
-    ($name:ident($($arg:expr),*)) => {
-        if $name($($arg),*) == 0 {
-            panic!(concat!(stringify!($name), " failed with: {}"),
-                    io::Error::last_os_error());
-        }
+    fn from_local_time(local_time: WinSystemTime) -> Result<Self, Error> {
+        let utc_time = local_time.as_utc_time()?;
+        let duration = InnerDuration::from_seconds(utc_time.as_unix_seconds()?);
+        Self::from_duration(duration)
     }
-}
-
-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 };
+    fn set_nsecs(&mut self, nsecs: i32) {
+        self.nsecs = nsecs;
     }
-}
 
-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)
-    }
-}
+    fn datetime(self) -> DateTime<Local> {
+        let st = self.inner.inner();
+
+        let date =
+            NaiveDate::from_ymd_opt(st.wYear as i32, st.wMonth as u32, st.wDay as u32).unwrap();
+        let time = NaiveTime::from_hms_nano(
+            st.wHour as u32,
+            st.wMinute as u32,
+            st.wSecond as u32,
+            self.nsecs as u32,
+        );
 
-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)
+        let offset = FixedOffset::east_opt(self.offset).unwrap();
+        DateTime::from_utc(date.and_time(time) - offset, offset)
     }
 }