blockworks-foundation
/
autobahn
mirror of https://github.com/blockworks-foundation/autobahn.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

update math

This commit is contained in:
none00y 2024-11-13 10:54:52 +01:00
parent e692dba055
commit 1c7fad771f
1 changed files with 34 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

50
lib/dex-invariant/src/internal/invariant-types/src/math.rs
View File

@ -1,5 +1,5 @@
use crate::{err, from_result, function, location, ok_or_mark_trace, structs::TickmapView, trace};
use std::{cell::RefMut, convert::TryInto};
use std::{cell::RefMut, convert::TryInto, convert::TryFrom};
use anchor_lang::*;
@ -441,6 +441,16 @@ fn get_next_sqrt_price_y_down(
// quotient= amount / L
// PRICE_LIQUIDITY_DENOMINATOR = 10 ^ (24 - 6)
let nominator = U256::from(amount.get())
.checked_mul(U256::from(Price::one::<U256>()))
.ok_or(err!("mul overflow"))?
.checked_mul(U256::from(Price::one::<U256>()))
.ok_or(err!("mul overflow"))?;
let denominator = U256::from(liquidity.get())
.checked_mul(U256::from(PRICE_LIQUIDITY_DENOMINATOR))
.ok_or(err!("mul overflow"))?;
if add {
// Price::from_scale(amount, TokenAmount::scale())
// max_nominator = max_amount * 10^24 => 2^144 so possible to overflow here
@ -455,26 +465,34 @@ fn get_next_sqrt_price_y_down(
// max_quotient = max_nominator / min_denominator
// max_quotient = 2^128 * 10^24 / 10^18 ~ 2^148 so possible to overflow in max_quote
let quotient = from_result!(Price::checked_from_decimal(amount)
.map_err(|err| err!(&err))? // TODO: add util macro to map str -> TrackableError
.checked_big_div_by_number(
U256::from(liquidity.get())
.checked_mul(U256::from(PRICE_LIQUIDITY_DENOMINATOR))
.ok_or_else(|| err!("mul overflow"))?,
))?;
let quotient = Price::new(
u128::try_from(
nominator
.checked_div(denominator)
.ok_or(err!("div overflow"))?,
)
.map_err(|_| err!("Failed to cast quotient to u128"))?,
);
// max_quotient = 2^128
// price_sqrt = 2^96
// possible to overflow in result
from_result!(price_sqrt.checked_add(quotient))
} else {
// Price::from_scale - same as case above
let quotient = from_result!(Price::checked_from_decimal(amount)
.map_err(|err| err!(&err))? // TODO: add util macro to map str -> TrackableError
.checked_big_div_by_number_up(
U256::from(liquidity.get())
.checked_mul(U256::from(PRICE_LIQUIDITY_DENOMINATOR))
.ok_or_else(|| err!("mul overflow"))?,
))?;
let quotient = Price::new(
u128::try_from(
nominator
.checked_add(
denominator
.checked_sub(U256::from(1))
.ok_or(err!("sub underflow"))?,
)
.ok_or(err!("add overflow"))?
.checked_div(denominator)
.ok_or(err!("div overflow"))?,
)
.map_err(|_| err!("Failed to cast quotient to u128"))?,
);
from_result!(price_sqrt.checked_sub(quotient))
}
}