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use std::ops::{Add, Sub, Div};
pub struct BCH {
m: i16,
t: i16,
prim_poly: u16,
n:i16,
}
pub fn div_round_up<T>(a: T, b: T) -> T
where
T: Copy + Add<Output = T> + Sub<Output = T> + Div<Output = T> + From<u8>,
{
(a + b - T::from(1)) / b
}
impl BCH {
pub fn build_gf_tables(self) {
let i: u16 = 1;
let x: u16 = 1;
//const k: u16 = 1 << deg(self.po);
}
/// Create a new BCH object initialized with
/// `m` - the Galois field order, must be in the 5-15 range
/// `t` - maximum error correction capability in bits
/// `prim_poly` - user-provided primitive polynomial
pub fn new(m: i16, t: i16, prim_poly: u16) -> Option<BCH> {
let err: u16 = 0;
let i: u16;
let genpoly: u32;
const MIN_M: i16 = 5;
const MAX_M: i16 = 15;
if (m < MIN_M) || (m > MAX_M) {
// `m` values must be between5 and 15 in this implementation
return None
}
let n = (1 << m) - 1;
let words = div_round_up(m * t, 32);
let ecc_bytes = div_round_up(m * t, 8);
let bch = BCH {
m,
t,
prim_poly,
n
};
Some(bch)
}
pub fn decode(self) -> i16{
return self.m
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_bch_init() {
let bch = BCH::new(6, 0, 0).unwrap();
assert_eq!(bch.decode(), 6);
}
#[test]
fn fail_m_values() {
let bch = BCH::new(4, 0, 0);
assert_eq!(bch.is_none(), true);
let bch = BCH::new(16, 0, 0);
assert_eq!(bch.is_none(), true);
}
}
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