use crate::{ctx::*, DekuError, DekuRead, DekuWrite};
use bitvec::prelude::*;
use std::collections::HashSet;
use std::hash::{BuildHasher, Hash};
#[allow(clippy::type_complexity)]
fn read_hashset_with_predicate<
'a,
T: DekuRead<'a, Ctx> + Eq + Hash,
S: BuildHasher + Default,
Ctx: Copy,
Predicate: FnMut(usize, &T) -> bool,
>(
input: &'a BitSlice<u8, Msb0>,
capacity: Option<usize>,
ctx: Ctx,
mut predicate: Predicate,
) -> Result<(&'a BitSlice<u8, Msb0>, HashSet<T, S>), DekuError> {
let mut res = HashSet::with_capacity_and_hasher(capacity.unwrap_or(0), S::default());
let mut rest = input;
let mut found_predicate = false;
while !found_predicate {
let (new_rest, val) = <T>::read(rest, ctx)?;
found_predicate = predicate(
unsafe { new_rest.as_bitptr().offset_from(input.as_bitptr()) } as usize,
&val,
);
res.insert(val);
rest = new_rest;
}
Ok((rest, res))
}
impl<
'a,
T: DekuRead<'a, Ctx> + Eq + Hash,
S: BuildHasher + Default,
Ctx: Copy,
Predicate: FnMut(&T) -> bool,
> DekuRead<'a, (Limit<T, Predicate>, Ctx)> for HashSet<T, S>
{
fn read(
input: &'a BitSlice<u8, Msb0>,
(limit, inner_ctx): (Limit<T, Predicate>, Ctx),
) -> Result<(&'a BitSlice<u8, Msb0>, Self), DekuError>
where
Self: Sized,
{
match limit {
Limit::Count(mut count) => {
if count == 0 {
return Ok((input, HashSet::<T, S>::default()));
}
read_hashset_with_predicate(input, Some(count), inner_ctx, move |_, _| {
count -= 1;
count == 0
})
}
Limit::Until(mut predicate, _) => {
read_hashset_with_predicate(input, None, inner_ctx, move |_, value| {
predicate(value)
})
}
Limit::BitSize(size) => {
let bit_size = size.0;
read_hashset_with_predicate(input, None, inner_ctx, move |read_bits, _| {
read_bits == bit_size
})
}
Limit::ByteSize(size) => {
let bit_size = size.0 * 8;
read_hashset_with_predicate(input, None, inner_ctx, move |read_bits, _| {
read_bits == bit_size
})
}
}
}
}
impl<'a, T: DekuRead<'a> + Eq + Hash, S: BuildHasher + Default, Predicate: FnMut(&T) -> bool>
DekuRead<'a, Limit<T, Predicate>> for HashSet<T, S>
{
fn read(
input: &'a BitSlice<u8, Msb0>,
limit: Limit<T, Predicate>,
) -> Result<(&'a BitSlice<u8, Msb0>, Self), DekuError>
where
Self: Sized,
{
Self::read(input, (limit, ()))
}
}
impl<T: DekuWrite<Ctx>, S, Ctx: Copy> DekuWrite<Ctx> for HashSet<T, S> {
fn write(&self, output: &mut BitVec<u8, Msb0>, inner_ctx: Ctx) -> Result<(), DekuError> {
for v in self {
v.write(output, inner_ctx)?;
}
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::*;
use rstest::rstest;
use rustc_hash::FxHashSet;
#[rstest(input, endian, bit_size, limit, expected, expected_rest,
case::count_0([0xAA].as_ref(), Endian::Little, Some(8), 0.into(), FxHashSet::default(), bits![u8, Msb0; 1, 0, 1, 0, 1, 0, 1, 0]),
case::count_1([0xAA, 0xBB].as_ref(), Endian::Little, Some(8), 1.into(), vec![0xAA].into_iter().collect(), bits![u8, Msb0; 1, 0, 1, 1, 1, 0, 1, 1]),
case::count_2([0xAA, 0xBB, 0xCC].as_ref(), Endian::Little, Some(8), 2.into(), vec![0xAA, 0xBB].into_iter().collect(), bits![u8, Msb0; 1, 1, 0, 0, 1, 1, 0, 0]),
case::until_null([0xAA, 0, 0xBB].as_ref(), Endian::Little, None, (|v: &u8| *v == 0u8).into(), vec![0xAA, 0].into_iter().collect(), bits![u8, Msb0; 1, 0, 1, 1, 1, 0, 1, 1]),
case::until_bits([0xAA, 0xBB].as_ref(), Endian::Little, None, BitSize(8).into(), vec![0xAA].into_iter().collect(), bits![u8, Msb0; 1, 0, 1, 1, 1, 0, 1, 1]),
case::bits_6([0b0110_1001, 0b1110_1001].as_ref(), Endian::Little, Some(6), 2.into(), vec![0b00_011010, 0b00_011110].into_iter().collect(), bits![u8, Msb0; 1, 0, 0, 1]),
#[should_panic(expected = "Parse(\"too much data: container of 8 bits cannot hold 9 bits\")")]
case::not_enough_data([].as_ref(), Endian::Little, Some(9), 1.into(), FxHashSet::default(), bits![u8, Msb0;]),
#[should_panic(expected = "Parse(\"too much data: container of 8 bits cannot hold 9 bits\")")]
case::not_enough_data([0xAA].as_ref(), Endian::Little, Some(9), 1.into(), FxHashSet::default(), bits![u8, Msb0;]),
#[should_panic(expected = "Incomplete(NeedSize { bits: 8 })")]
case::not_enough_data([0xAA].as_ref(), Endian::Little, Some(8), 2.into(), FxHashSet::default(), bits![u8, Msb0;]),
#[should_panic(expected = "Incomplete(NeedSize { bits: 8 })")]
case::not_enough_data_until([0xAA].as_ref(), Endian::Little, Some(8), (|_: &u8| false).into(), FxHashSet::default(), bits![u8, Msb0;]),
#[should_panic(expected = "Incomplete(NeedSize { bits: 8 })")]
case::not_enough_data_bits([0xAA].as_ref(), Endian::Little, Some(8), (BitSize(16)).into(), FxHashSet::default(), bits![u8, Msb0;]),
#[should_panic(expected = "Parse(\"too much data: container of 8 bits cannot hold 9 bits\")")]
case::too_much_data([0xAA, 0xBB].as_ref(), Endian::Little, Some(9), 1.into(), FxHashSet::default(), bits![u8, Msb0;]),
)]
fn test_hashset_read<Predicate: FnMut(&u8) -> bool>(
input: &[u8],
endian: Endian,
bit_size: Option<usize>,
limit: Limit<u8, Predicate>,
expected: FxHashSet<u8>,
expected_rest: &BitSlice<u8, Msb0>,
) {
let bit_slice = input.view_bits::<Msb0>();
let (rest, res_read) = match bit_size {
Some(bit_size) => {
FxHashSet::<u8>::read(bit_slice, (limit, (endian, BitSize(bit_size)))).unwrap()
}
None => FxHashSet::<u8>::read(bit_slice, (limit, (endian))).unwrap(),
};
assert_eq!(expected, res_read);
assert_eq!(expected_rest, rest);
}
#[rstest(input, endian, expected,
case::normal(vec![0xAABB, 0xCCDD].into_iter().collect(), Endian::Little, vec![0xDD, 0xCC, 0xBB, 0xAA]),
)]
fn test_hashset_write(input: FxHashSet<u16>, endian: Endian, expected: Vec<u8>) {
let mut res_write = bitvec![u8, Msb0;];
input.write(&mut res_write, endian).unwrap();
assert_eq!(expected, res_write.into_vec());
}
#[rstest(input, endian, bit_size, limit, expected, expected_rest, expected_write,
case::normal_le([0xAA, 0xBB, 0xCC, 0xDD].as_ref(), Endian::Little, Some(16), 2.into(), vec![0xBBAA, 0xDDCC].into_iter().collect(), bits![u8, Msb0;], vec![0xCC, 0xDD, 0xAA, 0xBB]),
case::normal_be([0xAA, 0xBB, 0xCC, 0xDD].as_ref(), Endian::Big, Some(16), 2.into(), vec![0xAABB, 0xCCDD].into_iter().collect(), bits![u8, Msb0;], vec![0xCC, 0xDD, 0xAA, 0xBB]),
case::predicate_le([0xAA, 0xBB, 0xCC, 0xDD].as_ref(), Endian::Little, Some(16), (|v: &u16| *v == 0xBBAA).into(), vec![0xBBAA].into_iter().collect(), bits![u8, Msb0; 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1], vec![0xAA, 0xBB]),
case::predicate_be([0xAA, 0xBB, 0xCC, 0xDD].as_ref(), Endian::Big, Some(16), (|v: &u16| *v == 0xAABB).into(), vec![0xAABB].into_iter().collect(), bits![u8, Msb0; 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1], vec![0xAA, 0xBB]),
case::bytes_le([0xAA, 0xBB, 0xCC, 0xDD].as_ref(), Endian::Little, Some(16), BitSize(16).into(), vec![0xBBAA].into_iter().collect(), bits![u8, Msb0; 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1], vec![0xAA, 0xBB]),
case::bytes_be([0xAA, 0xBB, 0xCC, 0xDD].as_ref(), Endian::Big, Some(16), BitSize(16).into(), vec![0xAABB].into_iter().collect(), bits![u8, Msb0; 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1], vec![0xAA, 0xBB]),
)]
fn test_hashset_read_write<Predicate: FnMut(&u16) -> bool>(
input: &[u8],
endian: Endian,
bit_size: Option<usize>,
limit: Limit<u16, Predicate>,
expected: FxHashSet<u16>,
expected_rest: &BitSlice<u8, Msb0>,
expected_write: Vec<u8>,
) {
let bit_slice = input.view_bits::<Msb0>();
let bit_size = bit_size.unwrap();
let (rest, res_read) =
FxHashSet::<u16>::read(bit_slice, (limit, (endian, BitSize(bit_size)))).unwrap();
assert_eq!(expected, res_read);
assert_eq!(expected_rest, rest);
let mut res_write = bitvec![u8, Msb0;];
res_read
.write(&mut res_write, (endian, BitSize(bit_size)))
.unwrap();
assert_eq!(expected_write, res_write.into_vec());
}
}