WIP: Added u24

Cargo.toml

@@ -23,6 +23,7 @@ subtle = { version = "2.2", default-features = false, features = ["nightly"] }
 serde_json = { version = "=1.0.69", default-features = false, features = ["alloc"] }
 embedded-time = "0.12.1"
 arbitrary = { version = "0.4.7", features = ["derive"], optional = true }
+num = { version = "0.4.0", default-features = false }
 
 [features]
 debug_allocations = ["lang_items/debug_allocations"]

src/api/clock.rs

@@ -0,0 +1,223 @@
+use embedded_time::TimeInt;
+use embedded_time::fraction::Fraction;
+use core::fmt;
+use core::ops::{Add, Sub, Mul, Div, Rem};
+
+#[derive(Clone, Copy, PartialOrd, Ord, PartialEq, Eq, fmt::Debug)]
+pub struct U24(u32);
+impl U24 {
+    pub const unsafe fn new_unchecked(n: u32) -> Self {
+        // SAFETY: this is guaranteed to be safe by the caller.
+        Self(n)
+    }
+
+    pub const fn new(n: u32) -> Option<Self> {
+        if n <= 0xffffff {
+            Some(Self(n))
+        } else {
+            None
+        }
+    }
+
+    pub const fn new_wrap(n: u32) -> Self {
+        Self(n & 0xffffff)
+    }
+
+    pub const fn get(self) -> u32 {
+        self.0
+    }
+}
+
+impl fmt::Display for U24 {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
+impl Add for U24 {
+    type Output = Self;
+    fn add(self, other: Self) -> Self {
+        let res = self.get().add(other.get());
+        debug_assert!(res <= 0xffffff);
+        Self::new_wrap(res)
+    }
+}
+
+impl Sub for U24 {
+    type Output = Self;
+    fn sub(self, other: Self) -> Self {
+        let res = self.get().sub(other.get());
+        // Note: underflow detection in debug is already done by u32's sub
+        Self::new_wrap(res)
+    }
+}
+
+impl Mul for U24 {
+    type Output = Self;
+    fn mul(self, other: Self) -> Self {
+        let res = self.get().mul(other.get());
+        debug_assert!(res <= 0xffffff);
+        Self::new_wrap(res)
+    }
+}
+
+impl Div for U24 {
+    type Output = Self;
+    fn div(self, other: Self) -> Self {
+        // SAFETY: division by zero detection is already done by u32's div
+        // and division cannot overflow
+        unsafe { Self::new_unchecked(self.get().div(other.get())) }
+    }
+}
+
+impl Rem for U24 {
+    type Output = Self;
+    fn rem(self, other: Self) -> Self {
+        // SAFETY: rem cannot overflow
+        unsafe { Self::new_unchecked(self.get().rem(other.get())) }
+    }
+}
+
+impl num::One for U24 {
+    fn one() -> Self {
+        Self(1)
+    }
+}
+
+impl num::Zero for U24 {
+    fn zero() -> Self {
+        Self(0)
+    }
+
+    fn is_zero(&self) -> bool {
+        self.get() == 0
+    }
+}
+
+impl num::Num for U24 {
+    type FromStrRadixErr = core::num::ParseIntError;
+    fn from_str_radix(str: &str, radix: u32) -> Result<Self, Self::FromStrRadixErr> {
+        u32::from_str_radix(str, radix)
+            .and_then(|n|
+                // If we are too big, we manually generate a ParseIntError
+                Self::new(n).ok_or_else(||
+                    u32::from_str_radix("100000000", 16).unwrap_err()
+                )
+            )
+    }
+}
+
+impl num::Integer for U24 {
+    fn div_floor(&self, other: &Self) -> Self {
+        // SAFETY: div_floor cannot overflow
+        unsafe { Self::new_unchecked(self.get().div_floor(&other.get())) }
+    }
+    fn mod_floor(&self, other: &Self) -> Self {
+        // SAFETY: div_floor cannot overflow
+        unsafe { Self::new_unchecked(self.get().mod_floor(&other.get())) }
+    }
+    fn gcd(&self, other: &Self) -> Self {
+        // SAFETY: gcd cannot overflow
+        unsafe { Self::new_unchecked(self.get().gcd(&other.get())) }
+    }
+    fn lcm(&self, other: &Self) -> Self {
+        Self::new(self.get().lcm(&other.get())).unwrap()
+    }
+    fn divides(&self, other: &Self) -> bool {
+        self.get().divides(&other.get())
+    }
+    fn is_multiple_of(&self, other: &Self) -> bool {
+        self.get().is_multiple_of(&other.get())
+    }
+    fn is_even(&self) -> bool {
+        self.get().is_even()
+    }
+    fn is_odd(&self) -> bool {
+        self.get().is_odd()
+    }
+    fn div_rem(&self, other: &Self) -> (Self, Self) {
+        let (div, rem) = self.get().div_rem(&other.get());
+        // SAFETY: div_floor cannot overflow
+        unsafe { ( Self::new_unchecked(div), Self::new_unchecked(rem) ) }
+    }
+}
+
+impl num::Bounded for U24 {
+    fn min_value() -> Self {
+        // SAFETY: 0 is within bounds
+        unsafe { Self::new_unchecked(0) }
+    }
+    fn max_value() -> Self {
+        // SAFETY: 0xffffff is within bounds
+        unsafe { Self::new_unchecked(0xffffff) }
+    }
+}
+
+impl num::traits::WrappingAdd for U24 {
+    fn wrapping_add(&self, v: &Self) -> Self {
+        Self::new_wrap(self.get().wrapping_add(v.get()))
+    }
+}
+
+impl num::traits::WrappingSub for U24 {
+    fn wrapping_sub(&self, v: &Self) -> Self {
+        Self::new_wrap(self.get().wrapping_sub(v.get()))
+    }
+}
+
+impl num::traits::CheckedAdd for U24 {
+    fn checked_add(&self, v: &Self) -> Option<Self> {
+        self.get()
+            .checked_add(v.get())
+            .and_then(|n| Self::new(n))
+    }
+}
+
+impl num::traits::CheckedSub for U24 {
+    fn checked_sub(&self, v: &Self) -> Option<Self> {
+        self.get()
+            .checked_sub(v.get())
+            // SAFETY: checked_sub cannot overflow
+            .and_then(|n| Some(unsafe { Self::new_unchecked(n) }))
+    }
+}
+
+impl num::traits::CheckedMul for U24 {
+    fn checked_mul(&self, v: &Self) -> Option<Self> {
+        self.get()
+            .checked_mul(v.get())
+            .and_then(|n| Self::new(n))
+    }
+}
+
+impl num::traits::CheckedDiv for U24 {
+    fn checked_div(&self, v: &Self) -> Option<Self> {
+        self.get()
+            .checked_div(v.get())
+            // SAFETY: checked_div cannot overflow
+            .and_then(|n| Some(unsafe { Self::new_unchecked(n) }))
+    }
+}
+
+impl From<u32> for U24 {
+    /// Use the 24 lowest bits from n, ignore the rest
+    fn from(n: u32) -> Self {
+        Self::new_wrap(n)
+    }
+}
+
+impl Mul<Fraction> for U24 {
+    type Output = Self;
+    fn mul(self, other: Fraction) -> Self {
+        Self::new(self.get() * other).unwrap()
+    }
+}
+
+impl Div<Fraction> for U24 {
+    type Output = Self;
+    fn div(self, other: Fraction) -> Self {
+        Self::new(self.get() / other).unwrap()
+    }
+}
+
+impl TimeInt for U24 {}

src/api/mod.rs

@@ -5,3 +5,4 @@
 
 pub mod firmware_protection;
 pub mod upgrade_storage;
+pub mod clock;

src/clock.rs

@@ -4,6 +4,8 @@ use embedded_time::duration::Milliseconds;
 pub use embedded_time::Clock;
 #[cfg(not(feature = "std"))]
 use libtock_drivers::result::FlexUnwrap;
+#[cfg(target_pointer_width = "32")]
+use super::api::clock::U24;
 
 #[cfg(not(feature = "std"))]
 pub struct LibtockClock<const CLOCK_FREQUENCY: u32>(libtock_drivers::timer::Timer<'static>);
@@ -28,7 +30,7 @@ const KEEPALIVE_DELAY_MS: ClockInt = 100;
 pub const KEEPALIVE_DELAY: Milliseconds<ClockInt> = Milliseconds(KEEPALIVE_DELAY_MS);
 
 #[cfg(target_pointer_width = "32")]
-pub type ClockInt = u32;
+pub type ClockInt = U24;
 #[cfg(target_pointer_width = "64")]
 pub type ClockInt = u64;