Files
darkfi/src/consensus/utils.rs
2022-12-13 15:19:09 +01:00

94 lines
3.0 KiB
Rust

/* This file is part of DarkFi (https://dark.fi)
*
* Copyright (C) 2020-2022 Dyne.org foundation
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
use darkfi_sdk::pasta::pallas;
use dashu::integer::{IBig, Sign};
use log::debug;
use super::Float10;
pub fn fbig2ibig(f: Float10) -> IBig {
let rad = IBig::try_from(10).unwrap();
let sig = f.repr().significand();
let exp = f.repr().exponent();
let val: IBig = if exp >= 0 { sig.clone() * rad.pow(exp as usize) } else { sig.clone() };
debug!("fbig2ibig (f): {}", f);
debug!("fbig2ibig (i): {}", val);
val
}
/*
pub fn base2ibig(base: pallas::Base) -> IBig {
//
let byts: [u8; 32] = base.to_repr();
let words: [u64; 4] = [
u64::from_le_bytes(byts[0..8].try_into().expect("")),
u64::from_le_bytes(byts[8..16].try_into().expect("")),
u64::from_le_bytes(byts[16..24].try_into().expect("")),
u64::from_le_bytes(byts[24..32].try_into().expect("")),
];
let uparts = UBig::from_words(&words);
//TODO both y, and t are positive, but workout the sign for general use
let ibig = IBig::from_parts(Sign::Positive, uparts);
ibig
}
*/
pub fn fbig2base(f: Float10) -> pallas::Base {
debug!("fbig -> base (f): {}", f);
let val: IBig = fbig2ibig(f);
let (sign, word) = val.as_sign_words();
let mut words: [u64; 4] = [0, 0, 0, 0];
words[..word.len()].copy_from_slice(word);
match sign {
Sign::Positive => pallas::Base::from_raw(words),
Sign::Negative => pallas::Base::from_raw(words).neg(),
}
}
#[cfg(test)]
mod tests {
use dashu::integer::IBig;
use crate::consensus::{constants::RADIX_BITS, types::Float10, utils::fbig2ibig};
#[test]
fn dashu_fbig2ibig() {
let f =
Float10::from_str_native("234234223.000").unwrap().with_precision(RADIX_BITS).value();
let i: IBig = fbig2ibig(f);
let sig = IBig::from(234234223);
assert_eq!(i, sig);
}
/*
#[test]
fn dashu_test_base2ibig() {
//
let fbig: Float10 = Float10::from_str_native(
"28948022309329048855892746252171976963363056481941560715954676764349967630337",
)
.unwrap()
.with_precision(RADIX_BITS)
.value();
let ibig = fbig2ibig(fbig.clone());
let res_base: pallas::Base = fbig2base(fbig.clone());
let res_ibig: IBig = base2ibig(res_base);
assert_eq!(res_ibig, ibig);
}
*/
}