65 lines
1.5 KiB
Rust
65 lines
1.5 KiB
Rust
// This Source Code Form is subject to the terms of the Mozilla Public
|
|
// License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
|
|
|
#[derive(Clone, Copy, PartialEq, Eq, Debug)]
|
|
pub(crate) enum Discriminant {
|
|
Boxed,
|
|
Inline,
|
|
}
|
|
|
|
impl Discriminant {
|
|
#[inline(always)]
|
|
pub(crate) const fn from_bit(bit: bool) -> Self {
|
|
if bit {
|
|
Self::Inline
|
|
} else {
|
|
Self::Boxed
|
|
}
|
|
}
|
|
|
|
#[inline(always)]
|
|
const fn bit(self) -> u8 {
|
|
match self {
|
|
Self::Boxed => 0,
|
|
Self::Inline => 1,
|
|
}
|
|
}
|
|
}
|
|
|
|
#[derive(Clone, Copy, Debug)]
|
|
pub(crate) struct Marker(u8);
|
|
|
|
impl Marker {
|
|
#[inline(always)]
|
|
const fn assemble(discriminant: Discriminant, data: u8) -> u8 {
|
|
data << 1 | discriminant.bit()
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) const fn empty() -> Self {
|
|
Self(Self::assemble(Discriminant::Inline, 0))
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) const fn new_inline(data: u8) -> Self {
|
|
debug_assert!(data < 0x80);
|
|
Self(Self::assemble(Discriminant::Inline, data))
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) const fn discriminant(self) -> Discriminant {
|
|
Discriminant::from_bit(self.0 & 0x01 != 0)
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) const fn data(self) -> u8 {
|
|
self.0 >> 1
|
|
}
|
|
|
|
#[inline(always)]
|
|
pub(crate) fn set_data(&mut self, byte: u8) {
|
|
debug_assert!(byte < 0x80);
|
|
self.0 = Self::assemble(self.discriminant(), byte);
|
|
}
|
|
}
|