Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 374 insertions, 0 deletions

diff --git a/vendor/bit_field/src/lib.rs b/vendor/bit_field/src/lib.rs
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+//! Provides the abstraction of a bit field, which allows for bit-level update and retrieval
+//! operations.
+
+#![no_std]
+
+#[cfg(test)]
+mod tests;
+
+use core::ops::{Bound, Range, RangeBounds};
+
+/// A generic trait which provides methods for extracting and setting specific bits or ranges of
+/// bits.
+pub trait BitField {
+    /// The number of bits in this bit field.
+    ///
+    /// ```rust
+    /// use bit_field::BitField;
+    ///
+    /// assert_eq!(u32::BIT_LENGTH, 32);
+    /// assert_eq!(u64::BIT_LENGTH, 64);
+    /// ```
+    const BIT_LENGTH: usize;
+
+    /// Obtains the bit at the index `bit`; note that index 0 is the least significant bit, while
+    /// index `length() - 1` is the most significant bit.
+    ///
+    /// ```rust
+    /// use bit_field::BitField;
+    ///
+    /// let value: u32 = 0b110101;
+    ///
+    /// assert_eq!(value.get_bit(1), false);
+    /// assert_eq!(value.get_bit(2), true);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the bit index is out of bounds of the bit field.
+    fn get_bit(&self, bit: usize) -> bool;
+
+    /// Obtains the range of bits specified by `range`; note that index 0 is the least significant
+    /// bit, while index `length() - 1` is the most significant bit.
+    ///
+    /// ```rust
+    /// use bit_field::BitField;
+    ///
+    /// let value: u32 = 0b110101;
+    ///
+    /// assert_eq!(value.get_bits(0..3), 0b101);
+    /// assert_eq!(value.get_bits(2..6), 0b1101);
+    /// assert_eq!(value.get_bits(..), 0b110101);
+    /// assert_eq!(value.get_bits(3..=3), value.get_bit(3) as u32);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the start or end indexes of the range are out of bounds of the
+    /// bit field.
+    fn get_bits<T: RangeBounds<usize>>(&self, range: T) -> Self;
+
+    /// Sets the bit at the index `bit` to the value `value` (where true means a value of '1' and
+    /// false means a value of '0'); note that index 0 is the least significant bit, while index
+    /// `length() - 1` is the most significant bit.
+    ///
+    /// ```rust
+    /// use bit_field::BitField;
+    ///
+    /// let mut value = 0u32;
+    ///
+    /// value.set_bit(1, true);
+    /// assert_eq!(value, 2u32);
+    ///
+    /// value.set_bit(3, true);
+    /// assert_eq!(value, 10u32);
+    ///
+    /// value.set_bit(1, false);
+    /// assert_eq!(value, 8u32);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the bit index is out of the bounds of the bit field.
+    fn set_bit(&mut self, bit: usize, value: bool) -> &mut Self;
+
+    /// Sets the range of bits defined by the range `range` to the lower bits of `value`; to be
+    /// specific, if the range is N bits long, the N lower bits of `value` will be used; if any of
+    /// the other bits in `value` are set to 1, this function will panic.
+    ///
+    /// ```rust
+    /// use bit_field::BitField;
+    ///
+    /// let mut value = 0u32;
+    ///
+    /// value.set_bits(0..2, 0b11);
+    /// assert_eq!(value, 0b11);
+    ///
+    /// value.set_bits(2..=3, 0b11);
+    /// assert_eq!(value, 0b1111);
+    ///
+    /// value.set_bits(..4, 0b1010);
+    /// assert_eq!(value, 0b1010);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the range is out of bounds of the bit field, or if there are `1`s
+    /// not in the lower N bits of `value`.
+    fn set_bits<T: RangeBounds<usize>>(&mut self, range: T, value: Self) -> &mut Self;
+}
+
+pub trait BitArray<T: BitField> {
+    /// Returns the length, eg number of bits, in this bit array.
+    ///
+    /// ```rust
+    /// use bit_field::BitArray;
+    ///
+    /// assert_eq!([0u8, 4u8, 8u8].bit_length(), 24);
+    /// assert_eq!([0u32, 5u32].bit_length(), 64);
+    /// ```
+    fn bit_length(&self) -> usize;
+
+    /// Obtains the bit at the index `bit`; note that index 0 is the least significant bit, while
+    /// index `length() - 1` is the most significant bit.
+    ///
+    /// ```rust
+    /// use bit_field::BitArray;
+    ///
+    /// let value: [u32; 1] = [0b110101];
+    ///
+    /// assert_eq!(value.get_bit(1), false);
+    /// assert_eq!(value.get_bit(2), true);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the bit index is out of bounds of the bit array.
+    fn get_bit(&self, bit: usize) -> bool;
+
+    /// Obtains the range of bits specified by `range`; note that index 0 is the least significant
+    /// bit, while index `length() - 1` is the most significant bit.
+    ///
+    /// ```rust
+    /// use bit_field::BitArray;
+    ///
+    /// let value: [u32; 2] = [0b110101, 0b11];
+    ///
+    /// assert_eq!(value.get_bits(0..3), 0b101);
+    /// assert_eq!(value.get_bits(..6), 0b110101);
+    /// assert_eq!(value.get_bits(31..33), 0b10);
+    /// assert_eq!(value.get_bits(5..=32), 0b1_0000_0000_0000_0000_0000_0000_001);
+    /// assert_eq!(value.get_bits(34..), 0);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the start or end indexes of the range are out of bounds of the
+    /// bit array, or if the range can't be contained by the bit field T.
+    fn get_bits<U: RangeBounds<usize>>(&self, range: U) -> T;
+
+    /// Sets the bit at the index `bit` to the value `value` (where true means a value of '1' and
+    /// false means a value of '0'); note that index 0 is the least significant bit, while index
+    /// `length() - 1` is the most significant bit.
+    ///
+    /// ```rust
+    /// use bit_field::BitArray;
+    ///
+    /// let mut value = [0u32];
+    ///
+    /// value.set_bit(1, true);
+    /// assert_eq!(value, [2u32]);
+    ///
+    /// value.set_bit(3, true);
+    /// assert_eq!(value, [10u32]);
+    ///
+    /// value.set_bit(1, false);
+    /// assert_eq!(value, [8u32]);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the bit index is out of the bounds of the bit array.
+    fn set_bit(&mut self, bit: usize, value: bool);
+
+    /// Sets the range of bits defined by the range `range` to the lower bits of `value`; to be
+    /// specific, if the range is N bits long, the N lower bits of `value` will be used; if any of
+    /// the other bits in `value` are set to 1, this function will panic.
+    ///
+    /// ```rust
+    /// use bit_field::BitArray;
+    ///
+    /// let mut value = [0u32, 0u32];
+    ///
+    /// value.set_bits(0..2, 0b11);
+    /// assert_eq!(value, [0b11, 0u32]);
+    ///
+    /// value.set_bits(31..35, 0b1010);
+    /// assert_eq!(value, [0x0003, 0b101]);
+    /// ```
+    ///
+    /// ## Panics
+    ///
+    /// This method will panic if the range is out of bounds of the bit array,
+    /// if the range can't be contained by the bit field T, or if there are `1`s
+    /// not in the lower N bits of `value`.
+    fn set_bits<U: RangeBounds<usize>>(&mut self, range: U, value: T);
+}
+
+/// An internal macro used for implementing BitField on the standard integral types.
+macro_rules! bitfield_numeric_impl {
+    ($($t:ty)*) => ($(
+        impl BitField for $t {
+            const BIT_LENGTH: usize = ::core::mem::size_of::<Self>() as usize * 8;
+
+            #[track_caller]
+            #[inline]
+            fn get_bit(&self, bit: usize) -> bool {
+                assert!(bit < Self::BIT_LENGTH);
+
+                (*self & (1 << bit)) != 0
+            }
+
+            #[track_caller]
+            #[inline]
+            fn get_bits<T: RangeBounds<usize>>(&self, range: T) -> Self {
+                let range = to_regular_range(&range, Self::BIT_LENGTH);
+
+                assert!(range.start < Self::BIT_LENGTH);
+                assert!(range.end <= Self::BIT_LENGTH);
+                assert!(range.start < range.end);
+
+                // shift away high bits
+                let bits = *self << (Self::BIT_LENGTH - range.end) >> (Self::BIT_LENGTH - range.end);
+
+                // shift away low bits
+                bits >> range.start
+            }
+
+            #[track_caller]
+            #[inline]
+            fn set_bit(&mut self, bit: usize, value: bool) -> &mut Self {
+                assert!(bit < Self::BIT_LENGTH);
+
+                if value {
+                    *self |= 1 << bit;
+                } else {
+                    *self &= !(1 << bit);
+                }
+
+                self
+            }
+
+            #[track_caller]
+            #[inline]
+            fn set_bits<T: RangeBounds<usize>>(&mut self, range: T, value: Self) -> &mut Self {
+                let range = to_regular_range(&range, Self::BIT_LENGTH);
+
+                assert!(range.start < Self::BIT_LENGTH);
+                assert!(range.end <= Self::BIT_LENGTH);
+                assert!(range.start < range.end);
+                assert!(value << (Self::BIT_LENGTH - (range.end - range.start)) >>
+                        (Self::BIT_LENGTH - (range.end - range.start)) == value,
+                        "value does not fit into bit range");
+
+                let bitmask: Self = !(!0 << (Self::BIT_LENGTH - range.end) >>
+                                    (Self::BIT_LENGTH - range.end) >>
+                                    range.start << range.start);
+
+                // set bits
+                *self = (*self & bitmask) | (value << range.start);
+
+                self
+            }
+        }
+    )*)
+}
+
+bitfield_numeric_impl! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize }
+
+impl<T: BitField> BitArray<T> for [T] {
+    #[inline]
+    fn bit_length(&self) -> usize {
+        self.len() * T::BIT_LENGTH
+    }
+
+    #[track_caller]
+    #[inline]
+    fn get_bit(&self, bit: usize) -> bool {
+        let slice_index = bit / T::BIT_LENGTH;
+        let bit_index = bit % T::BIT_LENGTH;
+        self[slice_index].get_bit(bit_index)
+    }
+
+    #[track_caller]
+    #[inline]
+    fn get_bits<U: RangeBounds<usize>>(&self, range: U) -> T {
+        let range = to_regular_range(&range, self.bit_length());
+
+        assert!(range.len() <= T::BIT_LENGTH);
+
+        let slice_start = range.start / T::BIT_LENGTH;
+        let slice_end = range.end / T::BIT_LENGTH;
+        let bit_start = range.start % T::BIT_LENGTH;
+        let bit_end = range.end % T::BIT_LENGTH;
+        let len = range.len();
+
+        assert!(slice_end - slice_start <= 1);
+
+        if slice_start == slice_end {
+            self[slice_start].get_bits(bit_start..bit_end)
+        } else if bit_end == 0 {
+            self[slice_start].get_bits(bit_start..T::BIT_LENGTH)
+        } else {
+            let mut ret = self[slice_start].get_bits(bit_start..T::BIT_LENGTH);
+            ret.set_bits(
+                (T::BIT_LENGTH - bit_start)..len,
+                self[slice_end].get_bits(0..bit_end),
+            );
+            ret
+        }
+    }
+
+    #[track_caller]
+    #[inline]
+    fn set_bit(&mut self, bit: usize, value: bool) {
+        let slice_index = bit / T::BIT_LENGTH;
+        let bit_index = bit % T::BIT_LENGTH;
+        self[slice_index].set_bit(bit_index, value);
+    }
+
+    #[track_caller]
+    #[inline]
+    fn set_bits<U: RangeBounds<usize>>(&mut self, range: U, value: T) {
+        let range = to_regular_range(&range, self.bit_length());
+
+        assert!(range.len() <= T::BIT_LENGTH);
+
+        let slice_start = range.start / T::BIT_LENGTH;
+        let slice_end = range.end / T::BIT_LENGTH;
+        let bit_start = range.start % T::BIT_LENGTH;
+        let bit_end = range.end % T::BIT_LENGTH;
+
+        assert!(slice_end - slice_start <= 1);
+
+        if slice_start == slice_end {
+            self[slice_start].set_bits(bit_start..bit_end, value);
+        } else if bit_end == 0 {
+            self[slice_start].set_bits(bit_start..T::BIT_LENGTH, value);
+        } else {
+            self[slice_start].set_bits(
+                bit_start..T::BIT_LENGTH,
+                value.get_bits(0..T::BIT_LENGTH - bit_start),
+            );
+            self[slice_end].set_bits(
+                0..bit_end,
+                value.get_bits(T::BIT_LENGTH - bit_start..T::BIT_LENGTH),
+            );
+        }
+    }
+}
+
+fn to_regular_range<T: RangeBounds<usize>>(generic_rage: &T, bit_length: usize) -> Range<usize> {
+    let start = match generic_rage.start_bound() {
+        Bound::Excluded(&value) => value + 1,
+        Bound::Included(&value) => value,
+        Bound::Unbounded => 0,
+    };
+    let end = match generic_rage.end_bound() {
+        Bound::Excluded(&value) => value,
+        Bound::Included(&value) => value + 1,
+        Bound::Unbounded => bit_length,
+    };
+
+    start..end
+}