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#![cfg_attr(feature = "no_std", no_std)]
extern crate c2rust_bitfields_derive;
pub use c2rust_bitfields_derive::BitfieldStruct;
pub trait FieldType: Sized {
const IS_SIGNED: bool;
#[cfg(not(feature = "no_std"))]
const TOTAL_BIT_SIZE: usize = ::std::mem::size_of::<Self>() * 8;
#[cfg(feature = "no_std")]
const TOTAL_BIT_SIZE: usize = ::core::mem::size_of::<Self>() * 8;
fn get_bit(&self, bit: usize) -> bool;
fn set_field(&self, field: &mut [u8], bit_range: (usize, usize)) {
fn zero_bit(byte: &mut u8, n_bit: u64) {
let bit = 1 << n_bit;
*byte &= !bit as u8;
}
fn one_bit(byte: &mut u8, n_bit: u64) {
let bit = 1 << n_bit;
*byte |= bit as u8;
}
let (lhs_bit, rhs_bit) = bit_range;
for (i, bit_index) in (lhs_bit..=rhs_bit).enumerate() {
let byte_index = bit_index / 8;
let byte = &mut field[byte_index];
if self.get_bit(i) {
one_bit(byte, (bit_index % 8) as u64);
} else {
zero_bit(byte, (bit_index % 8) as u64);
}
}
}
fn get_field(field: &[u8], bit_range: (usize, usize)) -> Self;
}
macro_rules! impl_int {
($($typ: ident),+) => {
$(
impl FieldType for $typ {
const IS_SIGNED: bool = $typ::min_value() != 0;
fn get_bit(&self, bit: usize) -> bool {
((*self >> bit) & 1) == 1
}
fn get_field(field: &[u8], bit_range: (usize, usize)) -> Self {
let (lhs_bit, rhs_bit) = bit_range;
let mut val = 0;
for (i, bit_index) in (lhs_bit..=rhs_bit).enumerate() {
let byte_index = bit_index / 8;
let byte = field[byte_index];
let bit = 1 << (bit_index % 8);
let read_bit = byte & bit;
if read_bit != 0 {
let write_bit = 1 << i;
val |= write_bit;
}
}
if Self::IS_SIGNED {
let bit_width = rhs_bit - lhs_bit + 1;
let unused_bits = Self::TOTAL_BIT_SIZE - bit_width;
val <<= unused_bits;
val >>= unused_bits;
}
val
}
}
)+
};
}
impl_int!{u8, u16, u32, u64, u128, i8, i16, i32, i64, i128}
impl FieldType for bool {
const IS_SIGNED: bool = false;
fn get_bit(&self, _bit: usize) -> bool {
*self
}
fn get_field(field: &[u8], bit_range: (usize, usize)) -> Self {
let (lhs_bit, rhs_bit) = bit_range;
let mut val = false;
for bit_index in lhs_bit..=rhs_bit {
let byte_index = bit_index / 8;
let byte = field[byte_index];
let bit = 1 << (bit_index % 8);
let read_bit = byte & bit;
if read_bit != 0 {
val = true;
}
}
val
}
}