CHANGELOG.md

@@ -8,9 +8,17 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 # [unreleased]
 
+## Fixed
+
+- CUC timestamp was fixed to include leap second corrections because it is based on the TAI
+  time reference. Changed the `TimeReader` trait to allow specifying leap seconds which might
+  be necessary for some timestamps to enable other API.
+
 ## Added
 
 - `From<$EcssEnum$TY> from $TY` for the ECSS enum type definitions.
+- Added basic support conversions to the `time` library. Introduce new `chrono` and `timelib`
+  feature gate
 
 # [v0.11.0-rc.0] 2024-03-04
 

Cargo.toml

@@ -34,9 +34,15 @@ optional = true
 default-features = false
 features = ["derive"]
 
+[dependencies.time]
+version = "0.3"
+default-features = false
+optional = true
+
 [dependencies.chrono]
 version = "0.4"
 default-features = false
+optional = true
 
 [dependencies.num-traits]
 version = "0.2"
@@ -50,6 +56,8 @@ default = ["std"]
 std = ["chrono/std", "chrono/clock", "alloc", "thiserror"]
 serde = ["dep:serde", "chrono/serde"]
 alloc = ["postcard/alloc", "chrono/alloc"]
+chrono = ["dep:chrono"]
+timelib = ["dep:time"]
 
 [package.metadata.docs.rs]
 all-features = true

README.md

@@ -43,6 +43,8 @@ deserializing them with an appropriate `serde` provider like
 ## Optional Features
 
  - [`serde`](https://serde.rs/): Adds `serde` support for most types by adding `Serialize` and `Deserialize` `derive`s
+ - [`chrono`](https://crates.io/crates/chrono): Add basic support for the `chrono` time library.
+ - [`timelib`](https://crates.io/crates/time): Add basic support for the `time` time library.
 
 # Examples
 

src/time/cds.rs

@@ -8,6 +8,7 @@ use super::*;
 use crate::private::Sealed;
 #[cfg(feature = "alloc")]
 use alloc::boxed::Box;
+#[cfg(feature = "chrono")]
 use chrono::Datelike;
 #[cfg(feature = "alloc")]
 use core::any::Any;
@@ -588,6 +589,20 @@ impl<ProvidesDaysLen: ProvidesDaysLength> TimeProvider<ProvidesDaysLen> {
         self.calc_unix_seconds(unix_days_seconds, ms_of_day);
     }
 
+    fn calc_ns_since_last_second(&self) -> u32 {
+        let mut ns_since_last_sec = (self.ms_of_day % 1000) * 10_u32.pow(6);
+        match self.submillis_precision() {
+            SubmillisPrecision::Microseconds => {
+                ns_since_last_sec += self.submillis() * 1000;
+            }
+            SubmillisPrecision::Picoseconds => {
+                ns_since_last_sec += self.submillis() / 1000;
+            }
+            _ => (),
+        }
+        ns_since_last_sec
+    }
+
     #[inline]
     fn calc_unix_seconds(&mut self, mut unix_days_seconds: i64, ms_of_day: u32) {
         let seconds_of_day = (ms_of_day / 1000) as i64;
@@ -599,7 +614,11 @@ impl<ProvidesDaysLen: ProvidesDaysLength> TimeProvider<ProvidesDaysLen> {
         self.unix_stamp = UnixTimestamp::const_new(unix_days_seconds, (ms_of_day % 1000) as u16);
     }
 
-    fn calc_date_time(&self, ns_since_last_second: u32) -> Option<DateTime<Utc>> {
+    #[cfg(feature = "chrono")]
+    fn calc_chrono_date_time(
+        &self,
+        ns_since_last_second: u32,
+    ) -> Option<chrono::DateTime<chrono::Utc>> {
         assert!(
             ns_since_last_second < 10_u32.pow(9),
             "Invalid MS since last second"
@@ -612,6 +631,17 @@ impl<ProvidesDaysLen: ProvidesDaysLength> TimeProvider<ProvidesDaysLen> {
         None
     }
 
+    #[cfg(feature = "timelib")]
+    fn calc_timelib_date_time(
+        &self,
+        ns_since_last_second: u32,
+    ) -> Result<time::OffsetDateTime, time::error::ComponentRange> {
+        Ok(
+            time::OffsetDateTime::from_unix_timestamp(self.unix_stamp.unix_seconds)?
+                + time::Duration::nanoseconds(ns_since_last_second.into()),
+        )
+    }
+
     fn length_check(&self, buf: &[u8], len_as_bytes: usize) -> Result<(), TimestampError> {
         if buf.len() < len_as_bytes {
             return Err(TimestampError::ByteConversion(
@@ -1155,29 +1185,27 @@ impl<ProvidesDaysLen: ProvidesDaysLength> CcsdsTimeProvider for TimeProvider<Pro
         self.unix_stamp
     }
 
-    fn date_time(&self) -> Option<DateTime<Utc>> {
-        let mut ns_since_last_sec = (self.ms_of_day % 1000) * 10_u32.pow(6);
-        match self.submillis_precision() {
-            SubmillisPrecision::Microseconds => {
-                ns_since_last_sec += self.submillis() * 1000;
-            }
-            SubmillisPrecision::Picoseconds => {
-                ns_since_last_sec += self.submillis() / 1000;
-            }
-            _ => (),
-        }
-        self.calc_date_time(ns_since_last_sec)
+    #[cfg(feature = "chrono")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "chrono")))]
+    fn chrono_date_time(&self) -> Option<chrono::DateTime<chrono::Utc>> {
+        self.calc_chrono_date_time(self.calc_ns_since_last_second())
+    }
+
+    #[cfg(feature = "timelib")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "timelib")))]
+    fn timelib_date_time(&self) -> Result<time::OffsetDateTime, time::error::ComponentRange> {
+        self.calc_timelib_date_time(self.calc_ns_since_last_second())
     }
 }
 
 impl TimeReader for TimeProvider<DaysLen16Bits> {
-    fn from_bytes(buf: &[u8]) -> Result<Self, TimestampError> {
+    fn from_bytes_generic(buf: &[u8], _leap_seconds: Option<u32>) -> Result<Self, TimestampError> {
         Self::from_bytes_with_u16_days(buf)
     }
 }
 
 impl TimeReader for TimeProvider<DaysLen24Bits> {
-    fn from_bytes(buf: &[u8]) -> Result<Self, TimestampError> {
+    fn from_bytes_generic(buf: &[u8], _leap_seconds: Option<u32>) -> Result<Self, TimestampError> {
         Self::from_bytes_with_u24_days(buf)
     }
 }
@@ -1329,7 +1357,7 @@ mod tests {
             time_stamper.p_field(),
             (1, [(CcsdsTimeCodes::Cds as u8) << 4, 0])
         );
-        let date_time = time_stamper.date_time().unwrap();
+        let date_time = time_stamper.chrono_date_time().unwrap();
         assert_eq!(date_time.year(), 1958);
         assert_eq!(date_time.month(), 1);
         assert_eq!(date_time.day(), 1);
@@ -1346,7 +1374,7 @@ mod tests {
             time_stamper.submillis_precision(),
             SubmillisPrecision::Absent
         );
-        let date_time = time_stamper.date_time().unwrap();
+        let date_time = time_stamper.chrono_date_time().unwrap();
         assert_eq!(date_time.year(), 1970);
         assert_eq!(date_time.month(), 1);
         assert_eq!(date_time.day(), 1);
@@ -1539,7 +1567,7 @@ mod tests {
         timestamp_now: TimeProvider<T>,
         compare_stamp: DateTime<Utc>,
     ) {
-        let dt = timestamp_now.date_time().unwrap();
+        let dt = timestamp_now.chrono_date_time().unwrap();
         if compare_stamp.year() > dt.year() {
             assert_eq!(compare_stamp.year() - dt.year(), 1);
         } else {
@@ -1736,7 +1764,7 @@ mod tests {
             time_provider.ms_of_day,
             30 * 1000 + 49 * 60 * 1000 + 16 * 60 * 60 * 1000 + subsec_millis
         );
-        assert_eq!(time_provider.date_time().unwrap(), datetime_utc);
+        assert_eq!(time_provider.chrono_date_time().unwrap(), datetime_utc);
     }
 
     #[test]
@@ -1790,7 +1818,7 @@ mod tests {
             SubmillisPrecision::Microseconds
         );
         assert_eq!(time_provider.submillis(), 500);
-        assert_eq!(time_provider.date_time().unwrap(), datetime_utc);
+        assert_eq!(time_provider.chrono_date_time().unwrap(), datetime_utc);
     }
 
     #[test]
@@ -1844,7 +1872,7 @@ mod tests {
             SubmillisPrecision::Picoseconds
         );
         assert_eq!(time_provider.submillis(), submilli_nanos * 1000);
-        assert_eq!(time_provider.date_time().unwrap(), datetime_utc);
+        assert_eq!(time_provider.chrono_date_time().unwrap(), datetime_utc);
     }
 
     #[test]
@@ -1917,7 +1945,7 @@ mod tests {
             time_provider.ms_of_day,
             30 * 1000 + 49 * 60 * 1000 + 16 * 60 * 60 * 1000 + subsec_millis
         );
-        let dt_back = time_provider.date_time().unwrap();
+        let dt_back = time_provider.chrono_date_time().unwrap();
         assert_eq!(datetime_utc, dt_back);
     }
 

src/time/cuc.rs

@@ -3,7 +3,10 @@
 //!
 //! The core data structure to do this is the [TimeProviderCcsdsEpoch] struct.
 use super::*;
+
+#[cfg(feature = "chrono")]
 use chrono::Datelike;
+
 use core::fmt::Debug;
 use core::ops::{Add, AddAssign};
 use core::time::Duration;
@@ -103,6 +106,7 @@ pub enum CucError {
         resolution: FractionalResolution,
         value: u64,
     },
+    LeapSecondCorrectionError,
 }
 
 impl Display for CucError {
@@ -120,6 +124,9 @@ impl Display for CucError {
                     "invalid cuc fractional part {value} for resolution {resolution:?}"
                 )
             }
+            CucError::LeapSecondCorrectionError => {
+                write!(f, "error while correcting for leap seconds")
+            }
         }
     }
 }
@@ -153,8 +160,10 @@ pub struct FractionalPart(FractionalResolution, u32);
 /// use spacepackets::time::cuc::{FractionalResolution, TimeProviderCcsdsEpoch};
 /// use spacepackets::time::{TimeWriter, CcsdsTimeCodes, TimeReader, CcsdsTimeProvider};
 ///
+/// const LEAP_SECONDS: u32 = 37;
 /// // Highest fractional resolution
-/// let timestamp_now = TimeProviderCcsdsEpoch::from_now(FractionalResolution::SixtyNs).expect("creating cuc stamp failed");
+/// let timestamp_now = TimeProviderCcsdsEpoch::from_now(FractionalResolution::SixtyNs, LEAP_SECONDS)
+///     .expect("creating cuc stamp failed");
 /// let mut raw_stamp = [0; 16];
 /// {
 ///     let written = timestamp_now.write_to_bytes(&mut raw_stamp).expect("writing timestamp failed");
@@ -163,7 +172,7 @@ pub struct FractionalPart(FractionalResolution, u32);
 ///     assert_eq!(written, 8);
 /// }
 /// {
-///     let read_result = TimeProviderCcsdsEpoch::from_bytes(&raw_stamp);
+///     let read_result = TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&raw_stamp, LEAP_SECONDS);
 ///     assert!(read_result.is_ok());
 ///     let stamp_deserialized = read_result.unwrap();
 ///     assert_eq!(stamp_deserialized, timestamp_now);
@@ -175,6 +184,7 @@ pub struct TimeProviderCcsdsEpoch {
     pfield: u8,
     counter: WidthCounterPair,
     fractions: Option<FractionalPart>,
+    leap_seconds: u32,
 }
 
 #[inline]
@@ -187,18 +197,26 @@ pub fn pfield_len(pfield: u8) -> usize {
 
 impl TimeProviderCcsdsEpoch {
     /// Create a time provider with a four byte counter and no fractional part.
-    pub fn new(counter: u32) -> Self {
+    pub fn new(counter: u32, leap_seconds: u32) -> Self {
         // These values are definitely valid, so it is okay to unwrap here.
-        Self::new_generic(WidthCounterPair(4, counter), None).unwrap()
+        Self::new_generic(WidthCounterPair(4, counter), None, leap_seconds).unwrap()
     }
 
     /// Like [TimeProviderCcsdsEpoch::new] but allow to supply a fractional part as well.
-    pub fn new_with_fractions(counter: u32, fractions: FractionalPart) -> Result<Self, CucError> {
-        Self::new_generic(WidthCounterPair(4, counter), Some(fractions))
+    pub fn new_with_fractions(
+        counter: u32,
+        fractions: FractionalPart,
+        leap_seconds: u32,
+    ) -> Result<Self, CucError> {
+        Self::new_generic(WidthCounterPair(4, counter), Some(fractions), leap_seconds)
     }
 
     /// Fractions with a resolution of ~ 4 ms
-    pub fn new_with_coarse_fractions(counter: u32, subsec_fractions: u8) -> Self {
+    pub fn new_with_coarse_fractions(
+        counter: u32,
+        subsec_fractions: u8,
+        leap_seconds: u32,
+    ) -> Self {
         // These values are definitely valid, so it is okay to unwrap here.
         Self::new_generic(
             WidthCounterPair(4, counter),
@@ -206,12 +224,17 @@ impl TimeProviderCcsdsEpoch {
                 FractionalResolution::FourMs,
                 subsec_fractions as u32,
             )),
+            leap_seconds,
         )
         .unwrap()
     }
 
     /// Fractions with a resolution of ~ 16 us
-    pub fn new_with_medium_fractions(counter: u32, subsec_fractions: u16) -> Self {
+    pub fn new_with_medium_fractions(
+        counter: u32,
+        subsec_fractions: u16,
+        leap_seconds: u32,
+    ) -> Self {
         // These values are definitely valid, so it is okay to unwrap here.
         Self::new_generic(
             WidthCounterPair(4, counter),
@@ -219,6 +242,7 @@ impl TimeProviderCcsdsEpoch {
                 FractionalResolution::FifteenUs,
                 subsec_fractions as u32,
             )),
+            leap_seconds,
         )
         .unwrap()
     }
@@ -226,40 +250,63 @@ impl TimeProviderCcsdsEpoch {
     /// Fractions with a resolution of ~ 60 ns. The fractional part value is limited by the
     /// 24 bits of the fractional field, so this function will fail with
     /// [CucError::InvalidFractions] if the fractional value exceeds the value.
-    pub fn new_with_fine_fractions(counter: u32, subsec_fractions: u32) -> Result<Self, CucError> {
+    pub fn new_with_fine_fractions(
+        counter: u32,
+        subsec_fractions: u32,
+        leap_seconds: u32,
+    ) -> Result<Self, CucError> {
         Self::new_generic(
             WidthCounterPair(4, counter),
             Some(FractionalPart(
                 FractionalResolution::SixtyNs,
                 subsec_fractions,
             )),
+            leap_seconds,
         )
     }
 
     /// This function will return the current time as a CUC timestamp.
     /// The counter width will always be set to 4 bytes because the normal CCSDS epoch will overflow
     /// when using less than that.
+    ///
+    /// The CUC timestamp uses TAI as the reference time system. Therefore, leap second corrections
+    /// must be applied on top of the UTC based time retrieved from the system in addition to the
+    /// conversion to the CCSDS epoch.
     #[cfg(feature = "std")]
     #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
-    pub fn from_now(fraction_resolution: FractionalResolution) -> Result<Self, StdTimestampError> {
+    pub fn from_now(
+        fraction_resolution: FractionalResolution,
+        leap_seconds: u32,
+    ) -> Result<Self, StdTimestampError> {
         let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)?;
         let ccsds_epoch = unix_epoch_to_ccsds_epoch(now.as_secs() as i64);
+        ccsds_epoch
+            .checked_add(i64::from(leap_seconds))
+            .ok_or(TimestampError::Cuc(CucError::LeapSecondCorrectionError))?;
         if fraction_resolution == FractionalResolution::Seconds {
-            return Ok(Self::new(ccsds_epoch as u32));
+            return Ok(Self::new(ccsds_epoch as u32, leap_seconds));
         }
         let fractions =
             fractional_part_from_subsec_ns(fraction_resolution, now.subsec_nanos() as u64);
-        Self::new_with_fractions(ccsds_epoch as u32, fractions.unwrap())
+        Self::new_with_fractions(ccsds_epoch as u32, fractions.unwrap(), leap_seconds)
             .map_err(|e| StdTimestampError::Timestamp(e.into()))
     }
 
     /// Updates the current time stamp from the current time. The fractional field width remains
     /// the same and will be updated accordingly.
+    ///
+    /// The CUC timestamp uses TAI as the reference time system. Therefore, leap second corrections
+    /// must be applied on top of the UTC based time retrieved from the system in addition to the
+    /// conversion to the CCSDS epoch.
     #[cfg(feature = "std")]
     #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
     pub fn update_from_now(&mut self) -> Result<(), StdTimestampError> {
         let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)?;
         self.counter.1 = unix_epoch_to_ccsds_epoch(now.as_secs() as i64) as u32;
+        self.counter
+            .1
+            .checked_add(self.leap_seconds)
+            .ok_or(TimestampError::Cuc(CucError::LeapSecondCorrectionError))?;
         if self.fractions.is_some() {
             self.fractions = fractional_part_from_subsec_ns(
                 self.fractions.unwrap().0,
@@ -269,17 +316,25 @@ impl TimeProviderCcsdsEpoch {
         Ok(())
     }
 
-    pub fn from_date_time(
-        dt: &DateTime<Utc>,
+    #[cfg(feature = "chrono")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "chrono")))]
+    pub fn from_chrono_date_time(
+        dt: &chrono::DateTime<chrono::Utc>,
         res: FractionalResolution,
+        leap_seconds: u32,
     ) -> Result<Self, TimestampError> {
         // Year before CCSDS epoch is invalid.
         if dt.year() < 1958 {
             return Err(TimestampError::DateBeforeCcsdsEpoch(*dt));
         }
+        let counter = dt
+            .timestamp()
+            .checked_add(i64::from(leap_seconds))
+            .ok_or(TimestampError::Cuc(CucError::LeapSecondCorrectionError))?;
         Self::new_generic(
-            WidthCounterPair(4, dt.timestamp() as u32),
+            WidthCounterPair(4, counter as u32),
             fractional_part_from_subsec_ns(res, dt.timestamp_subsec_nanos() as u64),
+            leap_seconds,
         )
         .map_err(|e| e.into())
     }
@@ -289,6 +344,7 @@ impl TimeProviderCcsdsEpoch {
     pub fn from_unix_stamp(
         unix_stamp: &UnixTimestamp,
         res: FractionalResolution,
+        leap_seconds: u32,
     ) -> Result<Self, TimestampError> {
         let ccsds_epoch = unix_epoch_to_ccsds_epoch(unix_stamp.unix_seconds);
         // Negative CCSDS epoch is invalid.
@@ -297,16 +353,24 @@ impl TimeProviderCcsdsEpoch {
                 unix_stamp.as_date_time().unwrap(),
             ));
         }
+        ccsds_epoch
+            .checked_add(i64::from(leap_seconds))
+            .ok_or(TimestampError::Cuc(CucError::LeapSecondCorrectionError))?;
         let fractions = fractional_part_from_subsec_ns(
             res,
             unix_stamp.subsecond_millis() as u64 * 10_u64.pow(6),
         );
-        Self::new_generic(WidthCounterPair(4, ccsds_epoch as u32), fractions).map_err(|e| e.into())
+        Self::new_generic(
+            WidthCounterPair(4, ccsds_epoch as u32),
+            fractions,
+            leap_seconds,
+        )
+        .map_err(|e| e.into())
     }
 
-    pub fn new_u16_counter(counter: u16) -> Self {
+    pub fn new_u16_counter(counter: u16, leap_seconds: u32) -> Self {
         // These values are definitely valid, so it is okay to unwrap here.
-        Self::new_generic(WidthCounterPair(2, counter as u32), None).unwrap()
+        Self::new_generic(WidthCounterPair(2, counter as u32), None, leap_seconds).unwrap()
     }
 
     pub fn width_counter_pair(&self) -> WidthCounterPair {
@@ -352,6 +416,7 @@ impl TimeProviderCcsdsEpoch {
     pub fn new_generic(
         counter: WidthCounterPair,
         fractions: Option<FractionalPart>,
+        leap_seconds: u32,
     ) -> Result<Self, CucError> {
         Self::verify_counter_width(counter.0)?;
         if counter.1 > (2u64.pow(counter.0 as u32 * 8) - 1) as u32 {
@@ -367,6 +432,7 @@ impl TimeProviderCcsdsEpoch {
             pfield: Self::build_p_field(counter.0, fractions.map(|v| v.0)),
             counter,
             fractions,
+            leap_seconds,
         })
     }
 
@@ -412,6 +478,8 @@ impl TimeProviderCcsdsEpoch {
     #[inline]
     fn unix_seconds(&self) -> i64 {
         ccsds_epoch_to_unix_epoch(self.counter.1 as i64)
+            .checked_sub(self.leap_seconds as i64)
+            .unwrap()
     }
 
     /// This returns the length of the individual components of the CUC timestamp in addition
@@ -458,10 +526,7 @@ impl TimeProviderCcsdsEpoch {
 }
 
 impl TimeReader for TimeProviderCcsdsEpoch {
-    fn from_bytes(buf: &[u8]) -> Result<Self, TimestampError>
-    where
-        Self: Sized,
-    {
+    fn from_bytes_generic(buf: &[u8], leap_seconds: Option<u32>) -> Result<Self, TimestampError> {
         if buf.len() < MIN_CUC_LEN {
             return Err(TimestampError::ByteConversion(
                 ByteConversionError::FromSliceTooSmall {
@@ -470,6 +535,9 @@ impl TimeReader for TimeProviderCcsdsEpoch {
                 },
             ));
         }
+        if leap_seconds.is_none() {
+            return Err(TimestampError::Cuc(CucError::LeapSecondCorrectionError));
+        }
         match ccsds_time_code_from_p_field(buf[0]) {
             Ok(code) => {
                 if code != CcsdsTimeCodes::CucCcsdsEpoch {
@@ -536,7 +604,11 @@ impl TimeReader for TimeProviderCcsdsEpoch {
                 _ => panic!("unreachable match arm"),
             }
         }
-        let provider = Self::new_generic(WidthCounterPair(cntr_len, counter), fractions)?;
+        let provider = Self::new_generic(
+            WidthCounterPair(cntr_len, counter),
+            fractions,
+            leap_seconds.unwrap(),
+        )?;
         Ok(provider)
     }
 }
@@ -621,18 +693,32 @@ impl CcsdsTimeProvider for TimeProviderCcsdsEpoch {
         0
     }
 
-    fn date_time(&self) -> Option<DateTime<Utc>> {
-        let unix_seconds = self.unix_seconds();
-        let ns = if let Some(fractional_part) = self.fractions {
-            convert_fractional_part_to_ns(fractional_part)
-        } else {
-            0
-        };
-        if let LocalResult::Single(res) = Utc.timestamp_opt(unix_seconds, ns as u32) {
+    #[cfg(feature = "chrono")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "chrono")))]
+    fn chrono_date_time(&self) -> Option<chrono::DateTime<chrono::Utc>> {
+        let mut ns = 0;
+        if let Some(fractional_part) = self.fractions {
+            ns = convert_fractional_part_to_ns(fractional_part);
+        }
+        if let LocalResult::Single(res) = chrono::Utc.timestamp_opt(self.unix_seconds(), ns as u32)
+        {
             return Some(res);
         }
         None
     }
+
+    #[cfg(feature = "timelib")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "timelib")))]
+    fn timelib_date_time(&self) -> Result<time::OffsetDateTime, time::error::ComponentRange> {
+        let mut ns = 0;
+        if let Some(fractional_part) = self.fractions {
+            ns = convert_fractional_part_to_ns(fractional_part);
+        }
+        Ok(
+            time::OffsetDateTime::from_unix_timestamp(self.unix_seconds())?
+                + time::Duration::nanoseconds(ns as i64),
+        )
+    }
 }
 
 fn get_provider_values_after_duration_addition(
@@ -704,9 +790,10 @@ impl Add<Duration> for TimeProviderCcsdsEpoch {
             get_provider_values_after_duration_addition(&self, duration);
         if let Some(fractional_part) = new_fractional_part {
             // The generated fractional part should always be valid, so its okay to unwrap here.
-            return Self::new_with_fractions(new_counter, fractional_part).unwrap();
+            return Self::new_with_fractions(new_counter, fractional_part, self.leap_seconds)
+                .unwrap();
         }
-        Self::new(new_counter)
+        Self::new(new_counter, self.leap_seconds)
     }
 }
 
@@ -718,9 +805,14 @@ impl Add<Duration> for &TimeProviderCcsdsEpoch {
             get_provider_values_after_duration_addition(self, duration);
         if let Some(fractional_part) = new_fractional_part {
             // The generated fractional part should always be valid, so its okay to unwrap here.
-            return Self::Output::new_with_fractions(new_counter, fractional_part).unwrap();
+            return Self::Output::new_with_fractions(
+                new_counter,
+                fractional_part,
+                self.leap_seconds,
+            )
+            .unwrap();
         }
-        Self::Output::new(new_counter)
+        Self::Output::new(new_counter, self.leap_seconds)
     }
 }
 
@@ -732,9 +824,12 @@ mod tests {
     #[allow(unused_imports)]
     use std::println;
 
+    const LEAP_SECONDS: u32 = 37;
+
     #[test]
     fn test_basic_zero_epoch() {
-        let zero_cuc = TimeProviderCcsdsEpoch::new(0);
+        // Include leap second correction for this.
+        let zero_cuc = TimeProviderCcsdsEpoch::new(0, LEAP_SECONDS);
         assert_eq!(zero_cuc.len_as_bytes(), 5);
         assert_eq!(zero_cuc.width(), zero_cuc.width_counter_pair().0);
         assert_eq!(zero_cuc.counter(), zero_cuc.width_counter_pair().1);
@@ -744,21 +839,25 @@ mod tests {
         assert_eq!(counter.1, 0);
         let fractions = zero_cuc.width_fractions_pair();
         assert!(fractions.is_none());
-        let dt = zero_cuc.date_time();
+        let dt = zero_cuc.chrono_date_time();
         assert!(dt.is_some());
         let dt = dt.unwrap();
-        assert_eq!(dt.year(), 1958);
-        assert_eq!(dt.month(), 1);
-        assert_eq!(dt.day(), 1);
-        assert_eq!(dt.hour(), 0);
-        assert_eq!(dt.minute(), 0);
-        assert_eq!(dt.second(), 0);
+        assert_eq!(dt.year(), 1957);
+        assert_eq!(dt.month(), 12);
+        assert_eq!(dt.day(), 31);
+        assert_eq!(dt.hour(), 23);
+        assert_eq!(dt.minute(), 59);
+        assert_eq!(dt.second(), 23);
     }
 
     #[test]
     fn test_write_no_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let zero_cuc = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(4, 0x20102030), None);
+        let zero_cuc = TimeProviderCcsdsEpoch::new_generic(
+            WidthCounterPair(4, 0x20102030),
+            None,
+            LEAP_SECONDS,
+        );
         assert!(zero_cuc.is_ok());
         let zero_cuc = zero_cuc.unwrap();
         let res = zero_cuc.write_to_bytes(&mut buf);
@@ -782,10 +881,10 @@ mod tests {
     #[test]
     fn test_datetime_now() {
         let now = Utc::now();
-        let cuc_now = TimeProviderCcsdsEpoch::from_now(FractionalResolution::SixtyNs);
+        let cuc_now = TimeProviderCcsdsEpoch::from_now(FractionalResolution::SixtyNs, LEAP_SECONDS);
         assert!(cuc_now.is_ok());
         let cuc_now = cuc_now.unwrap();
-        let dt_opt = cuc_now.date_time();
+        let dt_opt = cuc_now.chrono_date_time();
         assert!(dt_opt.is_some());
         let dt = dt_opt.unwrap();
         let diff = dt - now;
@@ -797,11 +896,16 @@ mod tests {
     #[test]
     fn test_read_no_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let zero_cuc =
-            TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(4, 0x20102030), None).unwrap();
+        let zero_cuc = TimeProviderCcsdsEpoch::new_generic(
+            WidthCounterPair(4, 0x20102030),
+            None,
+            LEAP_SECONDS,
+        )
+        .unwrap();
         zero_cuc.write_to_bytes(&mut buf).unwrap();
         let cuc_read_back =
-            TimeProviderCcsdsEpoch::from_bytes(&buf).expect("reading cuc timestamp failed");
+            TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS)
+                .expect("reading cuc timestamp failed");
         assert_eq!(cuc_read_back, zero_cuc);
         assert_eq!(cuc_read_back.width_counter_pair().1, 0x20102030);
         assert_eq!(cuc_read_back.width_fractions_pair(), None);
@@ -811,7 +915,8 @@ mod tests {
     fn invalid_read_len() {
         let mut buf: [u8; 16] = [0; 16];
         for i in 0..2 {
-            let res = TimeProviderCcsdsEpoch::from_bytes(&buf[0..i]);
+            let res =
+                TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf[0..i], LEAP_SECONDS);
             assert!(res.is_err());
             let err = res.unwrap_err();
             if let TimestampError::ByteConversion(ByteConversionError::FromSliceTooSmall {
@@ -823,10 +928,12 @@ mod tests {
                 assert_eq!(expected, 2);
             }
         }
-        let large_stamp = TimeProviderCcsdsEpoch::new_with_fine_fractions(22, 300).unwrap();
+        let large_stamp =
+            TimeProviderCcsdsEpoch::new_with_fine_fractions(22, 300, LEAP_SECONDS).unwrap();
         large_stamp.write_to_bytes(&mut buf).unwrap();
         for i in 2..large_stamp.len_as_bytes() - 1 {
-            let res = TimeProviderCcsdsEpoch::from_bytes(&buf[0..i]);
+            let res =
+                TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf[0..i], LEAP_SECONDS);
             assert!(res.is_err());
             let err = res.unwrap_err();
             if let TimestampError::ByteConversion(ByteConversionError::FromSliceTooSmall {
@@ -843,7 +950,7 @@ mod tests {
     #[test]
     fn write_and_read_tiny_stamp() {
         let mut buf = [0; 2];
-        let cuc = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(1, 200), None);
+        let cuc = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(1, 200), None, LEAP_SECONDS);
         assert!(cuc.is_ok());
         let cuc = cuc.unwrap();
         assert_eq!(cuc.len_as_bytes(), 2);
@@ -852,7 +959,8 @@ mod tests {
         let written = res.unwrap();
         assert_eq!(written, 2);
         assert_eq!(buf[1], 200);
-        let cuc_read_back = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let cuc_read_back =
+            TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(cuc_read_back.is_ok());
         let cuc_read_back = cuc_read_back.unwrap();
         assert_eq!(cuc_read_back, cuc);
@@ -861,7 +969,8 @@ mod tests {
     #[test]
     fn write_slightly_larger_stamp() {
         let mut buf = [0; 4];
-        let cuc = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(2, 40000), None);
+        let cuc =
+            TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(2, 40000), None, LEAP_SECONDS);
         assert!(cuc.is_ok());
         let cuc = cuc.unwrap();
         assert_eq!(cuc.len_as_bytes(), 3);
@@ -870,7 +979,8 @@ mod tests {
         let written = res.unwrap();
         assert_eq!(written, 3);
         assert_eq!(u16::from_be_bytes(buf[1..3].try_into().unwrap()), 40000);
-        let cuc_read_back = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let cuc_read_back =
+            TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(cuc_read_back.is_ok());
         let cuc_read_back = cuc_read_back.unwrap();
         assert_eq!(cuc_read_back, cuc);
@@ -882,7 +992,11 @@ mod tests {
     #[test]
     fn write_read_three_byte_cntr_stamp() {
         let mut buf = [0; 4];
-        let cuc = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(3, 2_u32.pow(24) - 2), None);
+        let cuc = TimeProviderCcsdsEpoch::new_generic(
+            WidthCounterPair(3, 2_u32.pow(24) - 2),
+            None,
+            LEAP_SECONDS,
+        );
         assert!(cuc.is_ok());
         let cuc = cuc.unwrap();
         assert_eq!(cuc.len_as_bytes(), 4);
@@ -893,7 +1007,8 @@ mod tests {
         let mut temp_buf = [0; 4];
         temp_buf[1..4].copy_from_slice(&buf[1..4]);
         assert_eq!(u32::from_be_bytes(temp_buf), 2_u32.pow(24) - 2);
-        let cuc_read_back = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let cuc_read_back =
+            TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(cuc_read_back.is_ok());
         let cuc_read_back = cuc_read_back.unwrap();
         assert_eq!(cuc_read_back, cuc);
@@ -902,7 +1017,7 @@ mod tests {
     #[test]
     fn test_write_invalid_buf() {
         let mut buf: [u8; 16] = [0; 16];
-        let res = TimeProviderCcsdsEpoch::new_with_fine_fractions(0, 0);
+        let res = TimeProviderCcsdsEpoch::new_with_fine_fractions(0, 0, LEAP_SECONDS);
         let cuc = res.unwrap();
         for i in 0..cuc.len_as_bytes() - 1 {
             let err = cuc.write_to_bytes(&mut buf[0..i]);
@@ -924,7 +1039,7 @@ mod tests {
     fn invalid_ccsds_stamp_type() {
         let mut buf: [u8; 16] = [0; 16];
         buf[0] |= (CcsdsTimeCodes::CucAgencyEpoch as u8) << 4;
-        let res = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let res = TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(res.is_err());
         let err = res.unwrap_err();
         if let TimestampError::InvalidTimeCode { expected, found } = err {
@@ -938,7 +1053,7 @@ mod tests {
     #[test]
     fn test_write_with_coarse_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let cuc = TimeProviderCcsdsEpoch::new_with_coarse_fractions(0x30201060, 120);
+        let cuc = TimeProviderCcsdsEpoch::new_with_coarse_fractions(0x30201060, 120, LEAP_SECONDS);
         assert!(cuc.fractions.is_some());
         assert_eq!(cuc.fractions.unwrap().1, 120);
         assert_eq!(cuc.fractions.unwrap().0, FractionalResolution::FourMs);
@@ -957,10 +1072,10 @@ mod tests {
     #[test]
     fn test_read_with_coarse_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let cuc = TimeProviderCcsdsEpoch::new_with_coarse_fractions(0x30201060, 120);
+        let cuc = TimeProviderCcsdsEpoch::new_with_coarse_fractions(0x30201060, 120, LEAP_SECONDS);
         let res = cuc.write_to_bytes(&mut buf);
         assert!(res.is_ok());
-        let res = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let res = TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(res.is_ok());
         let read_back = res.unwrap();
         assert_eq!(read_back, cuc);
@@ -969,7 +1084,8 @@ mod tests {
     #[test]
     fn test_write_with_medium_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let cuc = TimeProviderCcsdsEpoch::new_with_medium_fractions(0x30303030, 30000);
+        let cuc =
+            TimeProviderCcsdsEpoch::new_with_medium_fractions(0x30303030, 30000, LEAP_SECONDS);
         let res = cuc.write_to_bytes(&mut buf);
         assert!(res.is_ok());
         let written = res.unwrap();
@@ -981,10 +1097,11 @@ mod tests {
     #[test]
     fn test_read_with_medium_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let cuc = TimeProviderCcsdsEpoch::new_with_medium_fractions(0x30303030, 30000);
+        let cuc =
+            TimeProviderCcsdsEpoch::new_with_medium_fractions(0x30303030, 30000, LEAP_SECONDS);
         let res = cuc.write_to_bytes(&mut buf);
         assert!(res.is_ok());
-        let res = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let res = TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(res.is_ok());
         let cuc_read_back = res.unwrap();
         assert_eq!(cuc_read_back, cuc);
@@ -993,8 +1110,11 @@ mod tests {
     #[test]
     fn test_write_with_fine_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let cuc =
-            TimeProviderCcsdsEpoch::new_with_fine_fractions(0x30303030, u16::MAX as u32 + 60000);
+        let cuc = TimeProviderCcsdsEpoch::new_with_fine_fractions(
+            0x30303030,
+            u16::MAX as u32 + 60000,
+            LEAP_SECONDS,
+        );
         assert!(cuc.is_ok());
         let cuc = cuc.unwrap();
         let res = cuc.write_to_bytes(&mut buf);
@@ -1009,13 +1129,16 @@ mod tests {
     #[test]
     fn test_read_with_fine_fractions() {
         let mut buf: [u8; 16] = [0; 16];
-        let cuc =
-            TimeProviderCcsdsEpoch::new_with_fine_fractions(0x30303030, u16::MAX as u32 + 60000);
+        let cuc = TimeProviderCcsdsEpoch::new_with_fine_fractions(
+            0x30303030,
+            u16::MAX as u32 + 60000,
+            LEAP_SECONDS,
+        );
         assert!(cuc.is_ok());
         let cuc = cuc.unwrap();
         let res = cuc.write_to_bytes(&mut buf);
         assert!(res.is_ok());
-        let res = TimeProviderCcsdsEpoch::from_bytes(&buf);
+        let res = TimeProviderCcsdsEpoch::from_bytes_with_leap_seconds(&buf, LEAP_SECONDS);
         assert!(res.is_ok());
         let cuc_read_back = res.unwrap();
         assert_eq!(cuc_read_back, cuc);
@@ -1089,7 +1212,7 @@ mod tests {
 
     #[test]
     fn update_fractions() {
-        let mut stamp = TimeProviderCcsdsEpoch::new(2000);
+        let mut stamp = TimeProviderCcsdsEpoch::new(2000, LEAP_SECONDS);
         let res = stamp.set_fractions(FractionalPart(FractionalResolution::SixtyNs, 5000));
         assert!(res.is_ok());
         assert!(stamp.fractions.is_some());
@@ -1100,7 +1223,7 @@ mod tests {
 
     #[test]
     fn set_fract_resolution() {
-        let mut stamp = TimeProviderCcsdsEpoch::new(2000);
+        let mut stamp = TimeProviderCcsdsEpoch::new(2000, LEAP_SECONDS);
         stamp.set_fractional_resolution(FractionalResolution::SixtyNs);
         assert!(stamp.fractions.is_some());
         let fractions = stamp.fractions.unwrap();
@@ -1135,7 +1258,7 @@ mod tests {
 
     #[test]
     fn add_duration_basic() {
-        let mut cuc_stamp = TimeProviderCcsdsEpoch::new(200);
+        let mut cuc_stamp = TimeProviderCcsdsEpoch::new(200, LEAP_SECONDS);
         cuc_stamp.set_fractional_resolution(FractionalResolution::FifteenUs);
         let duration = Duration::from_millis(2500);
         cuc_stamp += duration;
@@ -1144,7 +1267,7 @@ mod tests {
 
     #[test]
     fn add_duration_basic_on_ref() {
-        let mut cuc_stamp = TimeProviderCcsdsEpoch::new(200);
+        let mut cuc_stamp = TimeProviderCcsdsEpoch::new(200, LEAP_SECONDS);
         cuc_stamp.set_fractional_resolution(FractionalResolution::FifteenUs);
         let duration = Duration::from_millis(2500);
         let new_stamp = cuc_stamp + duration;
@@ -1153,7 +1276,7 @@ mod tests {
 
     #[test]
     fn add_duration_basic_no_fractions() {
-        let mut cuc_stamp = TimeProviderCcsdsEpoch::new(200);
+        let mut cuc_stamp = TimeProviderCcsdsEpoch::new(200, LEAP_SECONDS);
         let duration = Duration::from_millis(2000);
         cuc_stamp += duration;
         assert_eq!(cuc_stamp.counter(), 202);
@@ -1162,7 +1285,7 @@ mod tests {
 
     #[test]
     fn add_duration_basic_on_ref_no_fractions() {
-        let cuc_stamp = TimeProviderCcsdsEpoch::new(200);
+        let cuc_stamp = TimeProviderCcsdsEpoch::new(200, LEAP_SECONDS);
         let duration = Duration::from_millis(2000);
         let new_stamp = cuc_stamp + duration;
         assert_eq!(new_stamp.counter(), 202);
@@ -1171,7 +1294,8 @@ mod tests {
     #[test]
     fn add_duration_overflow() {
         let mut cuc_stamp =
-            TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(1, 255), None).unwrap();
+            TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(1, 255), None, LEAP_SECONDS)
+                .unwrap();
         let duration = Duration::from_secs(10);
         cuc_stamp += duration;
         assert_eq!(cuc_stamp.counter.1, 10);
@@ -1179,7 +1303,7 @@ mod tests {
 
     #[test]
     fn test_invalid_width_param() {
-        let error = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(8, 0), None);
+        let error = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(8, 0), None, LEAP_SECONDS);
         assert!(error.is_err());
         let error = error.unwrap_err();
         if let CucError::InvalidCounterWidth(width) = error {
@@ -1193,14 +1317,18 @@ mod tests {
     #[test]
     fn test_from_dt() {
         let dt = Utc.with_ymd_and_hms(2021, 1, 1, 0, 0, 0).unwrap();
-        let cuc =
-            TimeProviderCcsdsEpoch::from_date_time(&dt, FractionalResolution::Seconds).unwrap();
-        assert_eq!(cuc.counter(), dt.timestamp() as u32);
+        let cuc = TimeProviderCcsdsEpoch::from_chrono_date_time(
+            &dt,
+            FractionalResolution::Seconds,
+            LEAP_SECONDS,
+        )
+        .unwrap();
+        assert_eq!(cuc.counter(), dt.timestamp() as u32 + LEAP_SECONDS);
     }
 
     #[test]
     fn test_new_u16_width() {
-        let cuc = TimeProviderCcsdsEpoch::new_u16_counter(0);
+        let cuc = TimeProviderCcsdsEpoch::new_u16_counter(0, LEAP_SECONDS);
         assert_eq!(cuc.width(), 2);
         assert_eq!(cuc.counter(), 0);
     }
@@ -1208,9 +1336,12 @@ mod tests {
     #[test]
     fn from_unix_stamp() {
         let unix_stamp = UnixTimestamp::new(0, 0).unwrap();
-        let cuc =
-            TimeProviderCcsdsEpoch::from_unix_stamp(&unix_stamp, FractionalResolution::Seconds)
-                .expect("failed to create cuc from unix stamp");
+        let cuc = TimeProviderCcsdsEpoch::from_unix_stamp(
+            &unix_stamp,
+            FractionalResolution::Seconds,
+            LEAP_SECONDS,
+        )
+        .expect("failed to create cuc from unix stamp");
         assert_eq!(
             cuc.counter(),
             (-DAYS_CCSDS_TO_UNIX * SECONDS_PER_DAY as i32) as u32
@@ -1219,7 +1350,8 @@ mod tests {
 
     #[test]
     fn test_invalid_counter() {
-        let cuc_error = TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(1, 256), None);
+        let cuc_error =
+            TimeProviderCcsdsEpoch::new_generic(WidthCounterPair(1, 256), None, LEAP_SECONDS);
         assert!(cuc_error.is_err());
         let cuc_error = cuc_error.unwrap_err();
         if let CucError::InvalidCounter { width, counter } = cuc_error {
@@ -1233,7 +1365,7 @@ mod tests {
 
     #[test]
     fn test_stamp_to_vec() {
-        let stamp = TimeProviderCcsdsEpoch::new_u16_counter(100);
+        let stamp = TimeProviderCcsdsEpoch::new_u16_counter(100, LEAP_SECONDS);
         let stamp_vec = stamp.to_vec().unwrap();
         let mut buf: [u8; 16] = [0; 16];
         stamp.write_to_bytes(&mut buf).unwrap();

src/time/mod.rs

@@ -204,10 +204,16 @@ pub trait TimeWriter {
     }
 }
 
-pub trait TimeReader {
-    fn from_bytes(buf: &[u8]) -> Result<Self, TimestampError>
-    where
-        Self: Sized;
+pub trait TimeReader: Sized {
+    fn from_bytes(buf: &[u8]) -> Result<Self, TimestampError> {
+        Self::from_bytes_generic(buf, None)
+    }
+
+    fn from_bytes_with_leap_seconds(buf: &[u8], leap_seconds: u32) -> Result<Self, TimestampError> {
+        Self::from_bytes_generic(buf, Some(leap_seconds))
+    }
+
+    fn from_bytes_generic(buf: &[u8], leap_seconds: Option<u32>) -> Result<Self, TimestampError>;
 }
 
 /// Trait for generic CCSDS time providers.
@@ -230,7 +236,13 @@ pub trait CcsdsTimeProvider {
         UnixTimestamp::const_new(self.unix_seconds(), self.subsecond_millis())
     }
 
-    fn date_time(&self) -> Option<DateTime<Utc>>;
+    #[cfg(feature = "chrono")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "chrono")))]
+    fn chrono_date_time(&self) -> Option<chrono::DateTime<chrono::Utc>>;
+
+    #[cfg(feature = "timelib")]
+    #[cfg_attr(doc_cfg, doc(cfg(feature = "timelib")))]
+    fn timelib_date_time(&self) -> Result<time::OffsetDateTime, time::error::ComponentRange>;
 }
 
 /// UNIX timestamp: Elapsed seconds since 1970-01-01T00:00:00+00:00.