add support for time::Time (#43)

Author: vnghia

Cargo.toml

@@ -20,6 +20,7 @@ bitcode_derive = { version = "=0.6.5", path = "./bitcode_derive", optional = tru
 bytemuck = { version = "1.14", features = [ "min_const_generics", "must_cast" ] }
 glam = { version = ">=0.21", default-features = false, optional = true }
 serde = { version = "1.0", default-features = false, features = [ "alloc" ], optional = true }
+time = { version = "0.3", default-features = false, optional = true }
 uuid = { version = "1.10", default-features = false, optional = true }
 
 [dev-dependencies]

fuzz/Cargo.toml

@@ -10,9 +10,10 @@ cargo-fuzz = true
 
 [dependencies]
 arrayvec = { version = "0.7", features = ["serde"] }
-bitcode = { path = "..", features = [ "arrayvec", "serde" ] }
+bitcode = { path = "..", features = [ "arrayvec", "serde", "time" ] }
 libfuzzer-sys = "0.4"
 serde = { version ="1.0", features = [ "derive" ] }
+time = { version = "0.3", features = ["serde"]}
 
 # Prevent this from interfering with workspaces
 [workspace]

fuzz/fuzz_targets/fuzz.rs

@@ -9,7 +9,7 @@ use std::collections::{BTreeMap, HashMap};
 use std::fmt::Debug;
 use std::num::NonZeroU32;
 use std::time::Duration;
-use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddrV4, SocketAddr, SocketAddrV6};
+use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
 
 #[inline(never)]
 fn test_derive<T: Debug + PartialEq + Encode + DecodeOwned>(data: &[u8]) {
@@ -216,5 +216,6 @@ fuzz_target!(|data: &[u8]| {
         SocketAddrV4,
         SocketAddrV6,
         SocketAddr,
+        time::Time,
     );
 });

src/derive/convert.rs

@@ -5,11 +5,14 @@ use core::num::NonZeroUsize;
 #[allow(unused)]
 macro_rules! impl_convert {
     ($want: path, $have: ty) => {
+        impl_convert!($want, $have, $have);
+    };
+    ($want: path, $have_encode: ty, $have_decode: ty) => {
         impl crate::derive::Encode for $want {
-            type Encoder = crate::derive::convert::ConvertIntoEncoder<$have>;
+            type Encoder = crate::derive::convert::ConvertIntoEncoder<$have_encode>;
         }
         impl<'a> crate::derive::Decode<'a> for $want {
-            type Decoder = crate::derive::convert::ConvertFromDecoder<'a, $have>;
+            type Decoder = crate::derive::convert::ConvertFromDecoder<'a, $have_decode>;
         }
     };
 }

src/derive/duration.rs

@@ -1,83 +1,27 @@
-use crate::coder::{Buffer, Decoder, Encoder, Result, View};
-use crate::{Decode, Encode};
-use alloc::vec::Vec;
-use bytemuck::CheckedBitPattern;
-use core::num::NonZeroUsize;
+use super::convert::{impl_convert, ConvertFrom};
+use crate::int::ranged_int;
 use core::time::Duration;
 
-#[derive(Default)]
-pub struct DurationEncoder {
-    secs: <u64 as Encode>::Encoder,
-    subsec_nanos: <u32 as Encode>::Encoder,
-}
-impl Encoder<Duration> for DurationEncoder {
-    #[inline(always)]
-    fn encode(&mut self, t: &Duration) {
-        self.secs.encode(&t.as_secs());
-        self.subsec_nanos.encode(&t.subsec_nanos());
-    }
-}
-impl Buffer for DurationEncoder {
-    fn collect_into(&mut self, out: &mut Vec<u8>) {
-        self.secs.collect_into(out);
-        self.subsec_nanos.collect_into(out);
-    }
+ranged_int!(Nanosecond, u32, 0, 999_999_999);
 
-    fn reserve(&mut self, additional: NonZeroUsize) {
-        self.secs.reserve(additional);
-        self.subsec_nanos.reserve(additional);
-    }
-}
-impl Encode for Duration {
-    type Encoder = DurationEncoder;
-}
+type DurationEncode = (u64, u32);
+type DurationDecode = (u64, Nanosecond);
 
-/// A u32 guaranteed to be < 1 billion. Prevents Duration::new from panicking.
-#[derive(Copy, Clone)]
-#[repr(transparent)]
-struct Nanoseconds(u32);
-// Safety: u32 and Nanoseconds have the same layout since Nanoseconds is #[repr(transparent)].
-unsafe impl CheckedBitPattern for Nanoseconds {
-    type Bits = u32;
+impl ConvertFrom<&Duration> for DurationEncode {
     #[inline(always)]
-    fn is_valid_bit_pattern(bits: &Self::Bits) -> bool {
-        *bits < 1_000_000_000
+    fn convert_from(value: &Duration) -> Self {
+        (value.as_secs(), value.subsec_nanos())
     }
 }
-impl<'a> Decode<'a> for Nanoseconds {
-    type Decoder = crate::int::CheckedIntDecoder<'a, Nanoseconds, u32>;
-}
 
-#[derive(Default)]
-pub struct DurationDecoder<'a> {
-    secs: <u64 as Decode<'a>>::Decoder,
-    subsec_nanos: <Nanoseconds as Decode<'a>>::Decoder,
-}
-impl<'a> View<'a> for DurationDecoder<'a> {
-    fn populate(&mut self, input: &mut &'a [u8], length: usize) -> Result<()> {
-        self.secs.populate(input, length)?;
-        self.subsec_nanos.populate(input, length)?;
-        Ok(())
-    }
-}
-impl<'a> Decoder<'a, Duration> for DurationDecoder<'a> {
+impl ConvertFrom<DurationDecode> for Duration {
     #[inline(always)]
-    fn decode(&mut self) -> Duration {
-        let secs = self.secs.decode();
-        let Nanoseconds(subsec_nanos) = self.subsec_nanos.decode();
-        // Makes Duration::new 4x faster since it can skip checks and division.
-        // Safety: impl CheckedBitPattern for Nanoseconds guarantees this.
-        unsafe {
-            if !Nanoseconds::is_valid_bit_pattern(&subsec_nanos) {
-                core::hint::unreachable_unchecked();
-            }
-        }
-        Duration::new(secs, subsec_nanos)
+    fn convert_from(value: DurationDecode) -> Self {
+        Duration::new(value.0, value.1.into_inner())
     }
 }
-impl<'a> Decode<'a> for Duration {
-    type Decoder = DurationDecoder<'a>;
-}
+
+impl_convert!(Duration, DurationEncode, DurationDecode);
 
 #[cfg(test)]
 mod tests {
@@ -95,5 +39,5 @@ mod tests {
             .map(|(s, n): (_, u32)| Duration::new(s, n % 1_000_000_000))
             .collect()
     }
-    crate::bench_encode_decode!(duration_vec: Vec<_>);
+    crate::bench_encode_decode!(duration_vec: Vec<Duration>);
 }

src/ext/mod.rs

@@ -3,6 +3,8 @@ mod arrayvec;
 #[cfg(feature = "glam")]
 #[rustfmt::skip] // Makes impl_struct! calls way longer.
 mod glam;
+#[cfg(feature = "time")]
+mod time;
 #[cfg(feature = "uuid")]
 mod uuid;
 

src/ext/time.rs

@@ -0,0 +1,68 @@
+use crate::convert::{impl_convert, ConvertFrom};
+use crate::int::ranged_int;
+use time::Time;
+
+ranged_int!(Hour, u8, 0, 23);
+ranged_int!(Minute, u8, 0, 59);
+ranged_int!(Second, u8, 0, 59);
+ranged_int!(Nanosecond, u32, 0, 999_999_999);
+
+type TimeEncode = (u8, u8, u8, u32);
+type TimeDecode = (Hour, Minute, Second, Nanosecond);
+impl_convert!(Time, TimeEncode, TimeDecode);
+
+impl ConvertFrom<&Time> for TimeEncode {
+    #[inline(always)]
+    fn convert_from(value: &Time) -> Self {
+        value.as_hms_nano()
+    }
+}
+
+impl ConvertFrom<TimeDecode> for Time {
+    #[inline(always)]
+    fn convert_from(value: TimeDecode) -> Self {
+        Time::from_hms_nano(
+            value.0.into_inner(),
+            value.1.into_inner(),
+            value.2.into_inner(),
+            value.3.into_inner(),
+        )
+        .unwrap()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[test]
+    fn test() {
+        assert!(crate::decode::<Time>(&crate::encode(
+            &Time::from_hms_nano(23, 59, 59, 999_999_999).unwrap()
+        ))
+        .is_ok());
+        assert!(crate::decode::<Time>(&crate::encode(&(23u8, 59u8, 59u8, 999_999_999u32))).is_ok());
+        assert!(
+            crate::decode::<Time>(&crate::encode(&(24u8, 59u8, 59u8, 999_999_999u32))).is_err()
+        );
+        assert!(
+            crate::decode::<Time>(&crate::encode(&(23u8, 60u8, 59u8, 999_999_999u32))).is_err()
+        );
+        assert!(
+            crate::decode::<Time>(&crate::encode(&(23u8, 59u8, 60u8, 999_999_999u32))).is_err()
+        );
+        assert!(
+            crate::decode::<Time>(&crate::encode(&(23u8, 59u8, 59u8, 1_000_000_000u32))).is_err()
+        );
+    }
+
+    use alloc::vec::Vec;
+    use time::Time;
+    fn bench_data() -> Vec<Time> {
+        crate::random_data(1000)
+            .into_iter()
+            .map(|(h, m, s, n): (u8, u8, u8, u32)| {
+                Time::from_hms_nano(h % 24, m % 60, s % 60, n % 1_000_000_000).unwrap()
+            })
+            .collect()
+    }
+    crate::bench_encode_decode!(duration_vec: Vec<_>);
+}

src/int.rs

@@ -127,6 +127,54 @@ where
     }
 }
 
+/// Prevents callers of `ranged_int` from accessing `.0` in the same source file.
+#[derive(Copy, Clone)]
+#[repr(transparent)]
+pub struct Private<T>(T);
+
+impl<T> Private<T> {
+    #[inline(always)]
+    pub fn into_inner(self) -> T {
+        self.0
+    }
+}
+
+#[allow(unused)]
+macro_rules! ranged_int {
+    ($type: ident, $int: ty, $lower: expr, $upper: expr) => {
+        #[derive(Copy, Clone)]
+        #[repr(transparent)]
+        pub struct $type(crate::int::Private<$int>);
+        // Safety: They have the same layout because of #[repr(transparent)].
+        unsafe impl bytemuck::CheckedBitPattern for $type {
+            type Bits = $int;
+            #[inline(always)]
+            fn is_valid_bit_pattern(bits: &Self::Bits) -> bool {
+                ($lower..=$upper).contains(bits)
+            }
+        }
+        impl $type {
+            #[inline(always)]
+            pub fn into_inner(self) -> $int {
+                if !<Self as bytemuck::CheckedBitPattern>::is_valid_bit_pattern(
+                    &self.0.into_inner(),
+                ) {
+                    // Safety: only created subject to `CheckedBitPattern`.
+                    unsafe { core::hint::unreachable_unchecked() };
+                }
+                self.0.into_inner()
+            }
+        }
+
+        impl<'a> crate::derive::Decode<'a> for $type {
+            type Decoder = crate::int::CheckedIntDecoder<'a, $type, $int>;
+        }
+    };
+}
+
+#[allow(unused)]
+pub(crate) use ranged_int;
+
 #[cfg(test)]
 mod tests {
     use crate::{decode, encode};