// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
pragma abicoder v2;
import './libraries/LowGasSafeMath.sol';
import './libraries/SafeCast.sol';
import './libraries/Tick.sol';
import './libraries/TickBitmap.sol';
import './libraries/Position.sol';
import './libraries/Oracle.sol';
import './libraries/Slot0.sol';
import './libraries/SwapCache.sol';
import './libraries/SwapState.sol';
import './libraries/StepComputations.sol';
import './libraries/SwapParams.sol';
import './libraries/FullMath.sol';
import './libraries/FixedPoint128.sol';
import './libraries/TransferHelper.sol';
import './libraries/TickMath.sol';
import './libraries/LiquidityMath.sol';
import './libraries/SwapMath.sol';
import './interfaces/ITangleswapFactory.sol';
import './interfaces/IERC20Minimal.sol';
import './interfaces/callback/ITangleswapSwapCallback.sol';
import './interfaces/IERC20Metadata.sol';
import './interfaces/ITangleswapLmPool.sol';
import './interfaces/IPriceOracle.sol';
import './interfaces/IERC721.sol';
contract SwapModule {
using LowGasSafeMath for uint256;
using LowGasSafeMath for int256;
using SafeCast for uint256;
using SafeCast for int256;
using Tick for mapping(int24 => Tick.Info);
using TickBitmap for mapping(int16 => uint256);
using Position for mapping(bytes32 => Position.Info);
using Position for Position.Info;
using Oracle for Oracle.Observation[65535];
/// @notice address of TangleswapFactory
address public factory;
/// @notice address of token0
address public token0;
/// @notice address of token1
address public token1;
/// @notice fee amount of this swap pool, 3000 means 0.3%
uint24 public fee;
/// @notice The pool tick spacing
int24 public tickSpacing;
/// @notice The maximum amount of position liquidity that can use any tick in the range
uint128 public maxLiquidityPerTick;
/// @notice The 0th storage slot in the pool stores many values, and is exposed as a single method to save gas
Slot0 public slot0;
/// @notice The fee growth as a Q128.128 fees of token0 collected per unit of liquidity for the entire life of the pool
uint256 public feeGrowthGlobal0X128;
/// @notice The fee growth as a Q128.128 fees of token1 collected per unit of liquidity for the entire life of the pool
uint256 public feeGrowthGlobal1X128;
// accumulated protocol fees in token0/token1 units
struct ProtocolFees {
uint128 token0;
uint128 token1;
}
/// @notice The amounts of token0 and token1 that are owed to the protocol
ProtocolFees public protocolFees;
/// @notice The currently in range liquidity available to the pool
uint128 public liquidity;
/// @notice Look up information about a specific tick in the pool
mapping(int24 => Tick.Info) public ticks;
/// @notice 256 packed tick initialized boolean values. See TickBitmap for more information
mapping(int16 => uint256) public tickBitmap;
/// @notice the information about a position by the position's key
mapping(bytes32 => Position.Info) public positions;
/// @notice data about a specific observation index
Oracle.Observation[65535] public observations;
/// @notice the address of price oracle
IPriceOracle public priceOracle;
// default value is 50(represent: 0.5%)
uint24 private constant minimumThreshold = 50;
/// @notice default value is 300(represent: 3%)
uint24 public maximumThreshold = 300;
/// @dev The percent of burn fee for buyback-and-burn of VOID
uint24 public burnFeePercent = 30;
/// @notice The total burn fee of token0 charged
uint256 public totalBurnFee0Charged;
/// @notice The total burn fee of token1 charged
uint256 public totalBurnFee1Charged;
/// @dev The original address of this contract
address private original;
// address of module to support swap
address private swapModule;
// liquidity mining
ITangleswapLmPool public lmPool;
/// @dev Get the pool's balance of token0
/// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
/// check
function balance0() private view returns (uint256) {
(bool success, bytes memory data) =
token0.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
require(success && data.length >= 32);
return abi.decode(data, (uint256));
}
/// @dev Get the pool's balance of token1
/// @dev This function is gas optimized to avoid a redundant extcodesize check in addition to the returndatasize
/// check
function balance1() private view returns (uint256) {
(bool success, bytes memory data) =
token1.staticcall(abi.encodeWithSelector(IERC20Minimal.balanceOf.selector, address(this)));
require(success && data.length >= 32);
return abi.decode(data, (uint256));
}
function swap(
SwapParams calldata swapParams
) external returns (int256 amount0, int256 amount1, uint160 stateSqrtPriceX96, uint128 stateLiquidity, int24 stateTick) {
bool zeroForOne = swapParams.zeroForOne;
require(swapParams.amountSpecified != 0, 'AS');
Slot0 memory slot0Start = slot0;
require(slot0Start.unlocked, 'LOK');
require(
zeroForOne
? swapParams.sqrtPriceLimitX96 < slot0Start.sqrtPriceX96 && swapParams.sqrtPriceLimitX96 > TickMath.MIN_SQRT_RATIO
: swapParams.sqrtPriceLimitX96 > slot0Start.sqrtPriceX96 && swapParams.sqrtPriceLimitX96 < TickMath.MAX_SQRT_RATIO,
'SPL'
);
slot0.unlocked = false;
SwapCache memory cache =
SwapCache({
liquidityStart: liquidity,
blockTimestamp: _blockTimestamp(),
feeProtocol: zeroForOne ? (slot0Start.feeProtocol % 16) : (slot0Start.feeProtocol >> 4),
secondsPerLiquidityCumulativeX128: 0,
tickCumulative: 0,
computedLatestObservation: false
});
if (address(lmPool) != address(0)) {
lmPool.accumulateReward(cache.blockTimestamp);
}
bool exactInput = swapParams.amountSpecified > 0;
SwapState memory state =
SwapState({
amountSpecifiedRemaining: swapParams.amountSpecified,
amountCalculated: 0,
sqrtPriceX96: slot0Start.sqrtPriceX96,
tick: slot0Start.tick,
feeGrowthGlobalX128: zeroForOne ? feeGrowthGlobal0X128 : feeGrowthGlobal1X128,
protocolFee: 0,
liquidity: cache.liquidityStart
});
// continue swapping as long as we haven't used the entire input/output and haven't reached the price limit
while (state.amountSpecifiedRemaining != 0 && state.sqrtPriceX96 != swapParams.sqrtPriceLimitX96) {
StepComputations memory step;
step.sqrtPriceStartX96 = state.sqrtPriceX96;
(step.tickNext, step.initialized) = tickBitmap.nextInitializedTickWithinOneWord(
state.tick,
tickSpacing,
zeroForOne
);
// ensure that we do not overshoot the min/max tick, as the tick bitmap is not aware of these bounds
if (step.tickNext < TickMath.MIN_TICK) {
step.tickNext = TickMath.MIN_TICK;
} else if (step.tickNext > TickMath.MAX_TICK) {
step.tickNext = TickMath.MAX_TICK;
}
// get the price for the next tick
step.sqrtPriceNextX96 = TickMath.getSqrtRatioAtTick(step.tickNext);
// compute values to swap to the target tick, price limit, or point where input/output amount is exhausted
(state.sqrtPriceX96, step.amountIn, step.amountOut, step.feeAmount) = SwapMath.computeSwapStep(
state.sqrtPriceX96,
(zeroForOne ? step.sqrtPriceNextX96 < swapParams.sqrtPriceLimitX96 : step.sqrtPriceNextX96 > swapParams.sqrtPriceLimitX96)
? swapParams.sqrtPriceLimitX96
: step.sqrtPriceNextX96,
state.liquidity,
state.amountSpecifiedRemaining,
fee
);
if (exactInput) {
state.amountSpecifiedRemaining -= (step.amountIn + step.feeAmount).toInt256();
state.amountCalculated = state.amountCalculated.sub(step.amountOut.toInt256());
} else {
state.amountSpecifiedRemaining += step.amountOut.toInt256();
state.amountCalculated = state.amountCalculated.add((step.amountIn + step.feeAmount).toInt256());
}
// if the protocol fee is on, calculate how much is owed, decrement feeAmount, and increment protocolFee
if (cache.feeProtocol > 0) {
uint256 delta = step.feeAmount / cache.feeProtocol;
step.feeAmount -= delta;
state.protocolFee += uint128(delta);
}
// if the oracle-based fee is on, increase swap fees by 25%
if (address(priceOracle) != address(0)) {
bool isDiffInRangeAndSwapDecreasingDiff = checkPriceDiff(zeroForOne, slot0Start.sqrtPriceX96);
if (isDiffInRangeAndSwapDecreasingDiff) {
step.feeAmount = FullMath.mulDiv(step.feeAmount, 5, 4);
state.protocolFee = uint128(FullMath.mulDiv(state.protocolFee, 5, 4));
}
}
// has NFT in his wallet, we will auto give him 10% discount on trading fee
if (
IERC721(ITangleswapFactory(factory).tangleSwapNFT()).balanceOf(
swapParams.recipient
) > 0
) {
step.feeAmount = FullMath.mulDiv(step.feeAmount, 9, 10);
}
// update global fee tracker
if (state.liquidity > 0) {
// calculate burn fee charged
step.chargedBurnFeeAmount = (step.feeAmount * burnFeePercent) / 100;
if (zeroForOne) {
totalBurnFee0Charged += step.chargedBurnFeeAmount;
} else {
totalBurnFee1Charged += step.chargedBurnFeeAmount;
}
state.feeGrowthGlobalX128 += FullMath.mulDiv(
step.feeAmount - step.chargedBurnFeeAmount,
FixedPoint128.Q128,
state.liquidity
);
}
// shift tick if we reached the next price
if (state.sqrtPriceX96 == step.sqrtPriceNextX96) {
// if the tick is initialized, run the tick transition
if (step.initialized) {
// check for the placeholder value, which we replace with the actual value the first time the swap
// crosses an initialized tick
if (!cache.computedLatestObservation) {
(cache.tickCumulative, cache.secondsPerLiquidityCumulativeX128) = observations.observeSingle(
cache.blockTimestamp,
0,
slot0Start.tick,
slot0Start.observationIndex,
cache.liquidityStart,
slot0Start.observationCardinality
);
cache.computedLatestObservation = true;
}
if (address(lmPool) != address(0)) {
lmPool.crossLmTick(step.tickNext, zeroForOne);
}
int128 liquidityNet =
ticks.cross(
step.tickNext,
(zeroForOne ? state.feeGrowthGlobalX128 : feeGrowthGlobal0X128),
(zeroForOne ? feeGrowthGlobal1X128 : state.feeGrowthGlobalX128),
cache.secondsPerLiquidityCumulativeX128,
cache.tickCumulative,
cache.blockTimestamp
);
// if we're moving leftward, we interpret liquidityNet as the opposite sign
// safe because liquidityNet cannot be type(int128).min
if (zeroForOne) liquidityNet = -liquidityNet;
state.liquidity = LiquidityMath.addDelta(state.liquidity, liquidityNet);
}
state.tick = zeroForOne ? step.tickNext - 1 : step.tickNext;
} else if (state.sqrtPriceX96 != step.sqrtPriceStartX96) {
// recompute unless we're on a lower tick boundary (i.e. already transitioned ticks), and haven't moved
state.tick = TickMath.getTickAtSqrtRatio(state.sqrtPriceX96);
}
}
// update tick and write an oracle entry if the tick change
if (state.tick != slot0Start.tick) {
(uint16 observationIndex, uint16 observationCardinality) =
observations.write(
slot0Start.observationIndex,
cache.blockTimestamp,
slot0Start.tick,
cache.liquidityStart,
slot0Start.observationCardinality,
slot0Start.observationCardinalityNext
);
(slot0.sqrtPriceX96, slot0.tick, slot0.observationIndex, slot0.observationCardinality) = (
state.sqrtPriceX96,
state.tick,
observationIndex,
observationCardinality
);
} else {
// otherwise just update the price
slot0.sqrtPriceX96 = state.sqrtPriceX96;
}
// update liquidity if it changed
if (cache.liquidityStart != state.liquidity) liquidity = state.liquidity;
// update fee growth global and, if necessary, protocol fees
// overflow is acceptable, protocol has to withdraw before it hits type(uint128).max fees
if (zeroForOne) {
feeGrowthGlobal0X128 = state.feeGrowthGlobalX128;
if (state.protocolFee > 0) protocolFees.token0 += state.protocolFee;
} else {
feeGrowthGlobal1X128 = state.feeGrowthGlobalX128;
if (state.protocolFee > 0) protocolFees.token1 += state.protocolFee;
}
(amount0, amount1) = zeroForOne == exactInput
? (swapParams.amountSpecified - state.amountSpecifiedRemaining, state.amountCalculated)
: (state.amountCalculated, swapParams.amountSpecified - state.amountSpecifiedRemaining);
// do the transfers and collect payment
if (zeroForOne) {
if (amount1 < 0) TransferHelper.safeTransfer(token1, swapParams.recipient, uint256(-amount1));
uint256 balance0Before = balance0();
ITangleswapSwapCallback(msg.sender).tangleswapSwapCallback(amount0, amount1, swapParams.data);
require(balance0Before.add(uint256(amount0)) <= balance0(), 'IIA');
} else {
if (amount0 < 0) TransferHelper.safeTransfer(token0, swapParams.recipient, uint256(-amount0));
uint256 balance1Before = balance1();
ITangleswapSwapCallback(msg.sender).tangleswapSwapCallback(amount0, amount1, swapParams.data);
require(balance1Before.add(uint256(amount1)) <= balance1(), 'IIA');
}
stateSqrtPriceX96 = state.sqrtPriceX96;
stateLiquidity = state.liquidity;
stateTick = state.tick;
slot0.unlocked = true;
}
/// @dev Returns the block timestamp truncated to 32 bits, i.e. mod 2**32. This method is overridden in tests.
function _blockTimestamp() internal view virtual returns (uint32) {
return uint32(block.timestamp); // truncation is desired
}
function checkPriceDiff(bool zeroForOne, uint160 sqrtPriceX96) internal view returns (bool) {
IPriceOracle iPriceOracle = IPriceOracle(priceOracle);
if (iPriceOracle.isOracleEnabled() && iPriceOracle.isOracleOperative()) {
// Need to determine whether to compare the price of token0 or token1
// is ratio of token1 over token0(true: token0/token1, false: token1/token0)
bool isRatioToken1OverToken0 = iPriceOracle.isRatioToken1OverToken0();
int256 oraclePrice = iPriceOracle.latestAnswer();
uint256 lpPrice = isRatioToken1OverToken0 ? getToken0Price(sqrtPriceX96) : getToken1Price(sqrtPriceX96); // lp token price
uint256 priceDiff;
if (uint256(oraclePrice) >= lpPrice) {
// oracle price >= lp price
priceDiff = uint256(oraclePrice) - lpPrice;
} else {
// oracle price < lp price
priceDiff = lpPrice - uint256(oraclePrice);
}
// is price_diff between 0.5% and 3%
bool isPriceDiffInRange =
priceDiff.mul(10000) > lpPrice.mul(minimumThreshold) &&
priceDiff.mul(10000) < lpPrice.mul(maximumThreshold);
// is swap decreasing price difference
bool isSwapDecreasingPriceDiff;
if (isPriceDiffInRange) {
if (zeroForOne) {
// case 1: token0 -> token1 (price of token0 will decrease, price of token1 will increase)
if (isRatioToken1OverToken0) {
// token0 price
if (uint256(oraclePrice) < lpPrice) {
isSwapDecreasingPriceDiff = true;
}
} else {
// token1 price
if (uint256(oraclePrice) >= lpPrice) {
isSwapDecreasingPriceDiff = true;
}
}
} else {
// case 2: token1 -> token0 (price of token0 will increase, price of token1 will decrease)
if (isRatioToken1OverToken0) {
// token0 price
if (uint256(oraclePrice) >= lpPrice) {
isSwapDecreasingPriceDiff = true;
}
} else {
// token1 price
if (uint256(oraclePrice) < lpPrice) {
isSwapDecreasingPriceDiff = true;
}
}
}
}
return isPriceDiffInRange && isSwapDecreasingPriceDiff;
}
return false;
}
/// Returns the current mid-price of the pool in terms of token0, i.e. the ratio of token1 over token0
function getToken0Price(uint160 sqrtPriceX96) internal view returns (uint256 price) {
uint8 token0Decimals = IERC20Metadata(token0).decimals();
return uint256(sqrtPriceX96).mul(uint256(sqrtPriceX96)).mul(10**token0Decimals) >> (96 * 2);
}
// Returns the current mid-price of the pool in terms of token1, i.e. the ratio of token0 over token1
function getToken1Price(uint160 sqrtPriceX96) internal view returns (uint256 price) {
uint8 token1Decimals = IERC20Metadata(token1).decimals();
return (10**token1Decimals).mul(2**192) / uint256(sqrtPriceX96).mul(uint256(sqrtPriceX96));
}
}
contracts/libraries/Slot0.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
struct Slot0 {
// the current price
uint160 sqrtPriceX96;
// the current tick
int24 tick;
// the most-recently updated index of the observations array
uint16 observationIndex;
// the current maximum number of observations that are being stored
uint16 observationCardinality;
// the next maximum number of observations to store, triggered in observations.write
uint16 observationCardinalityNext;
// the current protocol fee as a percentage of the swap fee taken on withdrawal
// represented as an integer denominator (1/x)%
uint8 feeProtocol;
// whether the pool is locked
bool unlocked;
}
contracts/libraries/SqrtPriceMath.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './LowGasSafeMath.sol';
import './SafeCast.sol';
import './FullMath.sol';
import './UnsafeMath.sol';
import './FixedPoint96.sol';
/// @title Functions based on Q64.96 sqrt price and liquidity
/// @notice Contains the math that uses square root of price as a Q64.96 and liquidity to compute deltas
library SqrtPriceMath {
using LowGasSafeMath for uint256;
using SafeCast for uint256;
/// @notice Gets the next sqrt price given a delta of token0
/// @dev Always rounds up, because in the exact output case (increasing price) we need to move the price at least
/// far enough to get the desired output amount, and in the exact input case (decreasing price) we need to move the
/// price less in order to not send too much output.
/// The most precise formula for this is liquidity * sqrtPX96 / (liquidity +- amount * sqrtPX96),
/// if this is impossible because of overflow, we calculate liquidity / (liquidity / sqrtPX96 +- amount).
/// @param sqrtPX96 The starting price, i.e. before accounting for the token0 delta
/// @param liquidity The amount of usable liquidity
/// @param amount How much of token0 to add or remove from virtual reserves
/// @param add Whether to add or remove the amount of token0
/// @return The price after adding or removing amount, depending on add
function getNextSqrtPriceFromAmount0RoundingUp(
uint160 sqrtPX96,
uint128 liquidity,
uint256 amount,
bool add
) internal pure returns (uint160) {
// we short circuit amount == 0 because the result is otherwise not guaranteed to equal the input price
if (amount == 0) return sqrtPX96;
uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
if (add) {
uint256 product;
if ((product = amount * sqrtPX96) / amount == sqrtPX96) {
uint256 denominator = numerator1 + product;
if (denominator >= numerator1)
// always fits in 160 bits
return uint160(FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator));
}
return uint160(UnsafeMath.divRoundingUp(numerator1, (numerator1 / sqrtPX96).add(amount)));
} else {
uint256 product;
// if the product overflows, we know the denominator underflows
// in addition, we must check that the denominator does not underflow
require((product = amount * sqrtPX96) / amount == sqrtPX96 && numerator1 > product);
uint256 denominator = numerator1 - product;
return FullMath.mulDivRoundingUp(numerator1, sqrtPX96, denominator).toUint160();
}
}
/// @notice Gets the next sqrt price given a delta of token1
/// @dev Always rounds down, because in the exact output case (decreasing price) we need to move the price at least
/// far enough to get the desired output amount, and in the exact input case (increasing price) we need to move the
/// price less in order to not send too much output.
/// The formula we compute is within <1 wei of the lossless version: sqrtPX96 +- amount / liquidity
/// @param sqrtPX96 The starting price, i.e., before accounting for the token1 delta
/// @param liquidity The amount of usable liquidity
/// @param amount How much of token1 to add, or remove, from virtual reserves
/// @param add Whether to add, or remove, the amount of token1
/// @return The price after adding or removing `amount`
function getNextSqrtPriceFromAmount1RoundingDown(
uint160 sqrtPX96,
uint128 liquidity,
uint256 amount,
bool add
) internal pure returns (uint160) {
// if we're adding (subtracting), rounding down requires rounding the quotient down (up)
// in both cases, avoid a mulDiv for most inputs
if (add) {
uint256 quotient =
(
amount <= type(uint160).max
? (amount << FixedPoint96.RESOLUTION) / liquidity
: FullMath.mulDiv(amount, FixedPoint96.Q96, liquidity)
);
return uint256(sqrtPX96).add(quotient).toUint160();
} else {
uint256 quotient =
(
amount <= type(uint160).max
? UnsafeMath.divRoundingUp(amount << FixedPoint96.RESOLUTION, liquidity)
: FullMath.mulDivRoundingUp(amount, FixedPoint96.Q96, liquidity)
);
require(sqrtPX96 > quotient);
// always fits 160 bits
return uint160(sqrtPX96 - quotient);
}
}
/// @notice Gets the next sqrt price given an input amount of token0 or token1
/// @dev Throws if price or liquidity are 0, or if the next price is out of bounds
/// @param sqrtPX96 The starting price, i.e., before accounting for the input amount
/// @param liquidity The amount of usable liquidity
/// @param amountIn How much of token0, or token1, is being swapped in
/// @param zeroForOne Whether the amount in is token0 or token1
/// @return sqrtQX96 The price after adding the input amount to token0 or token1
function getNextSqrtPriceFromInput(
uint160 sqrtPX96,
uint128 liquidity,
uint256 amountIn,
bool zeroForOne
) internal pure returns (uint160 sqrtQX96) {
require(sqrtPX96 > 0);
require(liquidity > 0);
// round to make sure that we don't pass the target price
return
zeroForOne
? getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountIn, true)
: getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountIn, true);
}
/// @notice Gets the next sqrt price given an output amount of token0 or token1
/// @dev Throws if price or liquidity are 0 or the next price is out of bounds
/// @param sqrtPX96 The starting price before accounting for the output amount
/// @param liquidity The amount of usable liquidity
/// @param amountOut How much of token0, or token1, is being swapped out
/// @param zeroForOne Whether the amount out is token0 or token1
/// @return sqrtQX96 The price after removing the output amount of token0 or token1
function getNextSqrtPriceFromOutput(
uint160 sqrtPX96,
uint128 liquidity,
uint256 amountOut,
bool zeroForOne
) internal pure returns (uint160 sqrtQX96) {
require(sqrtPX96 > 0);
require(liquidity > 0);
// round to make sure that we pass the target price
return
zeroForOne
? getNextSqrtPriceFromAmount1RoundingDown(sqrtPX96, liquidity, amountOut, false)
: getNextSqrtPriceFromAmount0RoundingUp(sqrtPX96, liquidity, amountOut, false);
}
/// @notice Gets the amount0 delta between two prices
/// @dev Calculates liquidity / sqrt(lower) - liquidity / sqrt(upper),
/// i.e. liquidity * (sqrt(upper) - sqrt(lower)) / (sqrt(upper) * sqrt(lower))
/// @param sqrtRatioAX96 A sqrt price
/// @param sqrtRatioBX96 Another sqrt price
/// @param liquidity The amount of usable liquidity
/// @param roundUp Whether to round the amount up or down
/// @return amount0 Amount of token0 required to cover a position of size liquidity between the two passed prices
function getAmount0Delta(
uint160 sqrtRatioAX96,
uint160 sqrtRatioBX96,
uint128 liquidity,
bool roundUp
) internal pure returns (uint256 amount0) {
if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
uint256 numerator1 = uint256(liquidity) << FixedPoint96.RESOLUTION;
uint256 numerator2 = sqrtRatioBX96 - sqrtRatioAX96;
require(sqrtRatioAX96 > 0);
return
roundUp
? UnsafeMath.divRoundingUp(
FullMath.mulDivRoundingUp(numerator1, numerator2, sqrtRatioBX96),
sqrtRatioAX96
)
: FullMath.mulDiv(numerator1, numerator2, sqrtRatioBX96) / sqrtRatioAX96;
}
/// @notice Gets the amount1 delta between two prices
/// @dev Calculates liquidity * (sqrt(upper) - sqrt(lower))
/// @param sqrtRatioAX96 A sqrt price
/// @param sqrtRatioBX96 Another sqrt price
/// @param liquidity The amount of usable liquidity
/// @param roundUp Whether to round the amount up, or down
/// @return amount1 Amount of token1 required to cover a position of size liquidity between the two passed prices
function getAmount1Delta(
uint160 sqrtRatioAX96,
uint160 sqrtRatioBX96,
uint128 liquidity,
bool roundUp
) internal pure returns (uint256 amount1) {
if (sqrtRatioAX96 > sqrtRatioBX96) (sqrtRatioAX96, sqrtRatioBX96) = (sqrtRatioBX96, sqrtRatioAX96);
return
roundUp
? FullMath.mulDivRoundingUp(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96)
: FullMath.mulDiv(liquidity, sqrtRatioBX96 - sqrtRatioAX96, FixedPoint96.Q96);
}
/// @notice Helper that gets signed token0 delta
/// @param sqrtRatioAX96 A sqrt price
/// @param sqrtRatioBX96 Another sqrt price
/// @param liquidity The change in liquidity for which to compute the amount0 delta
/// @return amount0 Amount of token0 corresponding to the passed liquidityDelta between the two prices
function getAmount0Delta(
uint160 sqrtRatioAX96,
uint160 sqrtRatioBX96,
int128 liquidity
) internal pure returns (int256 amount0) {
return
liquidity < 0
? -getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
: getAmount0Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
}
/// @notice Helper that gets signed token1 delta
/// @param sqrtRatioAX96 A sqrt price
/// @param sqrtRatioBX96 Another sqrt price
/// @param liquidity The change in liquidity for which to compute the amount1 delta
/// @return amount1 Amount of token1 corresponding to the passed liquidityDelta between the two prices
function getAmount1Delta(
uint160 sqrtRatioAX96,
uint160 sqrtRatioBX96,
int128 liquidity
) internal pure returns (int256 amount1) {
return
liquidity < 0
? -getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(-liquidity), false).toInt256()
: getAmount1Delta(sqrtRatioAX96, sqrtRatioBX96, uint128(liquidity), true).toInt256();
}
}
contracts/libraries/StepComputations.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
struct StepComputations {
// the price at the beginning of the step
uint160 sqrtPriceStartX96;
// the next tick to swap to from the current tick in the swap direction
int24 tickNext;
// whether tickNext is initialized or not
bool initialized;
// sqrt(price) for the next tick (1/0)
uint160 sqrtPriceNextX96;
// how much is being swapped in in this step
uint256 amountIn;
// how much is being swapped out
uint256 amountOut;
// how much fee is being paid in
uint256 feeAmount;
// how much fee is being charged by burn wallet
uint256 chargedBurnFeeAmount;
}
@openzeppelin/contracts/token/ERC20/IERC20.sol
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.0 <0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
contracts/interfaces/IERC20Metadata.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity ^0.7.0;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
/// @title IERC20Metadata
/// @title Interface for ERC20 Metadata
/// @notice Extension to IERC20 that includes token metadata
interface IERC20Metadata is IERC20 {
/// @return The name of the token
function name() external view returns (string memory);
/// @return The symbol of the token
function symbol() external view returns (string memory);
/// @return The number of decimal places the token has
function decimals() external view returns (uint8);
}
contracts/interfaces/IERC20Minimal.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Minimal ERC20 interface for Tangleswap
/// @notice Contains a subset of the full ERC20 interface that is used in Tangleswap
interface IERC20Minimal {
/// @notice Returns the balance of a token
/// @param account The account for which to look up the number of tokens it has, i.e. its balance
/// @return The number of tokens held by the account
function balanceOf(address account) external view returns (uint256);
/// @notice Transfers the amount of token from the `msg.sender` to the recipient
/// @param recipient The account that will receive the amount transferred
/// @param amount The number of tokens to send from the sender to the recipient
/// @return Returns true for a successful transfer, false for an unsuccessful transfer
function transfer(address recipient, uint256 amount) external returns (bool);
/// @notice Returns the current allowance given to a spender by an owner
/// @param owner The account of the token owner
/// @param spender The account of the token spender
/// @return The current allowance granted by `owner` to `spender`
function allowance(address owner, address spender) external view returns (uint256);
/// @notice Sets the allowance of a spender from the `msg.sender` to the value `amount`
/// @param spender The account which will be allowed to spend a given amount of the owners tokens
/// @param amount The amount of tokens allowed to be used by `spender`
/// @return Returns true for a successful approval, false for unsuccessful
function approve(address spender, uint256 amount) external returns (bool);
/// @notice Transfers `amount` tokens from `sender` to `recipient` up to the allowance given to the `msg.sender`
/// @param sender The account from which the transfer will be initiated
/// @param recipient The recipient of the transfer
/// @param amount The amount of the transfer
/// @return Returns true for a successful transfer, false for unsuccessful
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
/// @notice Event emitted when tokens are transferred from one address to another, either via `#transfer` or `#transferFrom`.
/// @param from The account from which the tokens were sent, i.e. the balance decreased
/// @param to The account to which the tokens were sent, i.e. the balance increased
/// @param value The amount of tokens that were transferred
event Transfer(address indexed from, address indexed to, uint256 value);
/// @notice Event emitted when the approval amount for the spender of a given owner's tokens changes.
/// @param owner The account that approved spending of its tokens
/// @param spender The account for which the spending allowance was modified
/// @param value The new allowance from the owner to the spender
event Approval(address indexed owner, address indexed spender, uint256 value);
}
contracts/interfaces/IERC721.sol
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/IERC721.sol)
pragma solidity =0.7.6;
/**
* @dev Required interface of an ERC721 compliant contract.
*/
interface IERC721 {
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must have been allowed to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC721
* or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
* understand this adds an external call which potentially creates a reentrancy vulnerability.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool approved) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
}
contracts/interfaces/IPriceOracle.sol
// SPDX-License-Identifier: MIT
pragma solidity >=0.5.0;
/// @title The interface for the Price Oracle
/// @notice Check the token0/token1 price using an Oracle
interface IPriceOracle {
// returns whether oracle is enabled.
function isOracleEnabled() external view returns (bool);
// returns whether Oracle is operative.
function isOracleOperative() external view returns (bool);
// is ratio of token1 over token0(true: token0/token1, false: token1/token0)
function isRatioToken1OverToken0() external view returns (bool);
// represents the number of decimals the oracle responses represent.
function decimals() external view returns (uint8);
// the current answer from oracle.
function latestAnswer() external view returns (int256);
// get the latest completed round where the answer was updated.
function latestTimestamp() external view returns (uint256);
// get data about the latest round
function latestRoundData()
external
view
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
);
// returns the description of the oracle. (for example: SMR/USDC)
function description() external view returns (string memory);
}
contracts/interfaces/ITangleswapFactory.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title The interface for the Tangleswap Factory
/// @notice The Tangleswap Factory facilitates creation of Tangleswap pools and control over the protocol fees
interface ITangleswapFactory {
/// @notice Emitted when the owner of the factory is changed
/// @param oldOwner The owner before the owner was changed
/// @param newOwner The owner after the owner was changed
event OwnerChanged(address indexed oldOwner, address indexed newOwner);
/// @notice Emitted when a pool is created
/// @param token0 The first token of the pool by address sort order
/// @param token1 The second token of the pool by address sort order
/// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
/// @param tickSpacing The minimum number of ticks between initialized ticks
/// @param pool The address of the created pool
event PoolCreated(
address indexed token0,
address indexed token1,
uint24 indexed fee,
int24 tickSpacing,
address pool
);
/// @notice Emitted when a new fee amount is enabled for pool creation via the factory
/// @param fee The enabled fee, denominated in hundredths of a bip
/// @param tickSpacing The minimum number of ticks between initialized ticks for pools created with the given fee
event FeeAmountEnabled(uint24 indexed fee, int24 indexed tickSpacing);
/// @notice Emitted when LM pool deployer is set
event SetLmPoolDeployer(address indexed lmPoolDeployer);
/// @notice Emitted when stMADA is set
event SetSTMADA(address indexed stMADA);
/// @notice Emitted when liquidStaking is set
event SetLiquidStaking(address indexed liquidStaking);
/// @notice Returns the current owner of the factory
/// @dev Can be changed by the current owner via setOwner
/// @return The address of the factory owner
function owner() external view returns (address);
/// @notice Returns the tick spacing for a given fee amount, if enabled, or 0 if not enabled
/// @dev A fee amount can never be removed, so this value should be hard coded or cached in the calling context
/// @param fee The enabled fee, denominated in hundredths of a bip. Returns 0 in case of unenabled fee
/// @return The tick spacing
function feeAmountTickSpacing(uint24 fee) external view returns (int24);
/// @notice Returns the pool address for a given pair of tokens and a fee, or address 0 if it does not exist
/// @dev tokenA and tokenB may be passed in either token0/token1 or token1/token0 order
/// @param tokenA The contract address of either token0 or token1
/// @param tokenB The contract address of the other token
/// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
/// @return pool The pool address
function getPool(
address tokenA,
address tokenB,
uint24 fee
) external view returns (address pool);
/// @notice Creates a pool for the given two tokens and fee
/// @param tokenA One of the two tokens in the desired pool
/// @param tokenB The other of the two tokens in the desired pool
/// @param fee The desired fee for the pool
/// @dev tokenA and tokenB may be passed in either order: token0/token1 or token1/token0. tickSpacing is retrieved
/// from the fee. The call will revert if the pool already exists, the fee is invalid, or the token arguments
/// are invalid.
/// @return pool The address of the newly created pool
function createPool(
address tokenA,
address tokenB,
uint24 fee
) external returns (address pool);
/// @notice Updates the owner of the factory
/// @dev Must be called by the current owner
/// @param _owner The new owner of the factory
function setOwner(address _owner) external;
/// @notice Enables a fee amount with the given tickSpacing
/// @dev Fee amounts may never be removed once enabled
/// @param fee The fee amount to enable, denominated in hundredths of a bip (i.e. 1e-6)
/// @param tickSpacing The spacing between ticks to be enforced for all pools created with the given fee amount
function enableFeeAmount(uint24 fee, int24 tickSpacing) external;
/// @notice Burn Wallet (used for buyback-and-burn of VOID)
/// @dev Can be changed by the current owner via modifyBurnWallet
/// @return The address of burn wallet
function burnWallet() external view returns (address);
/// @notice Update burn wallet
/// @dev Must be called by the current owner
/// @param _burnWallet The new burn wallet
function modifyBurnWallet(address _burnWallet) external;
/// @notice Initialize tangleSwapNFT address
/// @dev The tangleSwapNFT address will be initialized when TangleSwapNFT contract deployed, and it can only be initialized once
function initTangleSwapNFT(address _tangleSwapNFT) external;
/// @return Returns current tangleSwapNFT address
function tangleSwapNFT() external view returns (address);
/// @return Returns swap module address
function swapModule() external view returns (address);
/// @return Returns Liquidity Mining Pool deployer
function lmPoolDeployer() external view returns (address);
/// @return Returns Cardano stMADA
function stMADA() external view returns (address);
/// @return Returns Cardano Liquid Staking
function liquidStaking() external view returns (address);
function setSTMADA(address _stMADA) external;
function setLiquidStaking(address _liquidStaking) external;
function setLmPoolDeployer(address _lmPoolDeployer) external;
function setLmPool(address pool, address lmPool) external;
}
contracts/interfaces/ITangleswapLmPool.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
interface ITangleswapLmPool {
function accumulateReward(uint32 currTimestamp) external;
function crossLmTick(int24 tick, bool zeroForOne) external;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Callback for ITangleswapPoolActions#swap
/// @notice Any contract that calls ITangleswapPoolActions#swap must implement this interface
interface ITangleswapSwapCallback {
/// @notice Called to `msg.sender` after executing a swap via ITangleswapPool#swap.
/// @dev In the implementation you must pay the pool tokens owed for the swap.
/// The caller of this method must be checked to be a TangleswapPool deployed by the canonical TangleswapFactory.
/// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
/// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
/// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
/// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
/// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
/// @param data Any data passed through by the caller via the ITangleswapPoolActions#swap call
function tangleswapSwapCallback(
int256 amount0Delta,
int256 amount1Delta,
bytes calldata data
) external;
}
contracts/libraries/BitMath.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title BitMath
/// @dev This library provides functionality for computing bit properties of an unsigned integer
library BitMath {
/// @notice Returns the index of the most significant bit of the number,
/// where the least significant bit is at index 0 and the most significant bit is at index 255
/// @dev The function satisfies the property:
/// x >= 2**mostSignificantBit(x) and x < 2**(mostSignificantBit(x)+1)
/// @param x the value for which to compute the most significant bit, must be greater than 0
/// @return r the index of the most significant bit
function mostSignificantBit(uint256 x) internal pure returns (uint8 r) {
require(x > 0);
if (x >= 0x100000000000000000000000000000000) {
x >>= 128;
r += 128;
}
if (x >= 0x10000000000000000) {
x >>= 64;
r += 64;
}
if (x >= 0x100000000) {
x >>= 32;
r += 32;
}
if (x >= 0x10000) {
x >>= 16;
r += 16;
}
if (x >= 0x100) {
x >>= 8;
r += 8;
}
if (x >= 0x10) {
x >>= 4;
r += 4;
}
if (x >= 0x4) {
x >>= 2;
r += 2;
}
if (x >= 0x2) r += 1;
}
/// @notice Returns the index of the least significant bit of the number,
/// where the least significant bit is at index 0 and the most significant bit is at index 255
/// @dev The function satisfies the property:
/// (x & 2**leastSignificantBit(x)) != 0 and (x & (2**(leastSignificantBit(x)) - 1)) == 0)
/// @param x the value for which to compute the least significant bit, must be greater than 0
/// @return r the index of the least significant bit
function leastSignificantBit(uint256 x) internal pure returns (uint8 r) {
require(x > 0);
r = 255;
if (x & type(uint128).max > 0) {
r -= 128;
} else {
x >>= 128;
}
if (x & type(uint64).max > 0) {
r -= 64;
} else {
x >>= 64;
}
if (x & type(uint32).max > 0) {
r -= 32;
} else {
x >>= 32;
}
if (x & type(uint16).max > 0) {
r -= 16;
} else {
x >>= 16;
}
if (x & type(uint8).max > 0) {
r -= 8;
} else {
x >>= 8;
}
if (x & 0xf > 0) {
r -= 4;
} else {
x >>= 4;
}
if (x & 0x3 > 0) {
r -= 2;
} else {
x >>= 2;
}
if (x & 0x1 > 0) r -= 1;
}
}
contracts/libraries/FixedPoint128.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.4.0;
/// @title FixedPoint128
/// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
library FixedPoint128 {
uint256 internal constant Q128 = 0x100000000000000000000000000000000;
}
contracts/libraries/FixedPoint96.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.4.0;
/// @title FixedPoint96
/// @notice A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format)
/// @dev Used in SqrtPriceMath.sol
library FixedPoint96 {
uint8 internal constant RESOLUTION = 96;
uint256 internal constant Q96 = 0x1000000000000000000000000;
}
contracts/libraries/FullMath.sol
// SPDX-License-Identifier: MIT
pragma solidity >=0.4.0 <0.8.0;
/// @title Contains 512-bit math functions
/// @notice Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision
/// @dev Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits
library FullMath {
/// @notice Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
/// @param a The multiplicand
/// @param b The multiplier
/// @param denominator The divisor
/// @return result The 256-bit result
/// @dev Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv
function mulDiv(
uint256 a,
uint256 b,
uint256 denominator
) internal pure returns (uint256 result) {
// 512-bit multiply [prod1 prod0] = a * b
// Compute the product mod 2**256 and mod 2**256 - 1
// then use the Chinese Remainder Theorem to reconstruct
// the 512 bit result. The result is stored in two 256
// variables such that product = prod1 * 2**256 + prod0
uint256 prod0; // Least significant 256 bits of the product
uint256 prod1; // Most significant 256 bits of the product
assembly {
let mm := mulmod(a, b, not(0))
prod0 := mul(a, b)
prod1 := sub(sub(mm, prod0), lt(mm, prod0))
}
// Handle non-overflow cases, 256 by 256 division
if (prod1 == 0) {
require(denominator > 0);
assembly {
result := div(prod0, denominator)
}
return result;
}
// Make sure the result is less than 2**256.
// Also prevents denominator == 0
require(denominator > prod1);
///////////////////////////////////////////////
// 512 by 256 division.
///////////////////////////////////////////////
// Make division exact by subtracting the remainder from [prod1 prod0]
// Compute remainder using mulmod
uint256 remainder;
assembly {
remainder := mulmod(a, b, denominator)
}
// Subtract 256 bit number from 512 bit number
assembly {
prod1 := sub(prod1, gt(remainder, prod0))
prod0 := sub(prod0, remainder)
}
// Factor powers of two out of denominator
// Compute largest power of two divisor of denominator.
// Always >= 1.
uint256 twos = -denominator & denominator;
// Divide denominator by power of two
assembly {
denominator := div(denominator, twos)
}
// Divide [prod1 prod0] by the factors of two
assembly {
prod0 := div(prod0, twos)
}
// Shift in bits from prod1 into prod0. For this we need
// to flip `twos` such that it is 2**256 / twos.
// If twos is zero, then it becomes one
assembly {
twos := add(div(sub(0, twos), twos), 1)
}
prod0 |= prod1 * twos;
// Invert denominator mod 2**256
// Now that denominator is an odd number, it has an inverse
// modulo 2**256 such that denominator * inv = 1 mod 2**256.
// Compute the inverse by starting with a seed that is correct
// correct for four bits. That is, denominator * inv = 1 mod 2**4
uint256 inv = (3 * denominator) ^ 2;
// Now use Newton-Raphson iteration to improve the precision.
// Thanks to Hensel's lifting lemma, this also works in modular
// arithmetic, doubling the correct bits in each step.
inv *= 2 - denominator * inv; // inverse mod 2**8
inv *= 2 - denominator * inv; // inverse mod 2**16
inv *= 2 - denominator * inv; // inverse mod 2**32
inv *= 2 - denominator * inv; // inverse mod 2**64
inv *= 2 - denominator * inv; // inverse mod 2**128
inv *= 2 - denominator * inv; // inverse mod 2**256
// Because the division is now exact we can divide by multiplying
// with the modular inverse of denominator. This will give us the
// correct result modulo 2**256. Since the precoditions guarantee
// that the outcome is less than 2**256, this is the final result.
// We don't need to compute the high bits of the result and prod1
// is no longer required.
result = prod0 * inv;
return result;
}
/// @notice Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
/// @param a The multiplicand
/// @param b The multiplier
/// @param denominator The divisor
/// @return result The 256-bit result
function mulDivRoundingUp(
uint256 a,
uint256 b,
uint256 denominator
) internal pure returns (uint256 result) {
result = mulDiv(a, b, denominator);
if (mulmod(a, b, denominator) > 0) {
require(result < type(uint256).max);
result++;
}
}
}
contracts/libraries/LiquidityMath.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Math library for liquidity
library LiquidityMath {
/// @notice Add a signed liquidity delta to liquidity and revert if it overflows or underflows
/// @param x The liquidity before change
/// @param y The delta by which liquidity should be changed
/// @return z The liquidity delta
function addDelta(uint128 x, int128 y) internal pure returns (uint128 z) {
if (y < 0) {
require((z = x - uint128(-y)) < x, 'LS');
} else {
require((z = x + uint128(y)) >= x, 'LA');
}
}
}
contracts/libraries/LowGasSafeMath.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.7.0;
/// @title Optimized overflow and underflow safe math operations
/// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
library LowGasSafeMath {
/// @notice Returns x + y, reverts if sum overflows uint256
/// @param x The augend
/// @param y The addend
/// @return z The sum of x and y
function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
require((z = x + y) >= x);
}
/// @notice Returns x - y, reverts if underflows
/// @param x The minuend
/// @param y The subtrahend
/// @return z The difference of x and y
function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
require((z = x - y) <= x);
}
/// @notice Returns x * y, reverts if overflows
/// @param x The multiplicand
/// @param y The multiplier
/// @return z The product of x and y
function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
require(x == 0 || (z = x * y) / x == y);
}
/// @notice Returns x + y, reverts if overflows or underflows
/// @param x The augend
/// @param y The addend
/// @return z The sum of x and y
function add(int256 x, int256 y) internal pure returns (int256 z) {
require((z = x + y) >= x == (y >= 0));
}
/// @notice Returns x - y, reverts if overflows or underflows
/// @param x The minuend
/// @param y The subtrahend
/// @return z The difference of x and y
function sub(int256 x, int256 y) internal pure returns (int256 z) {
require((z = x - y) <= x == (y >= 0));
}
}
contracts/libraries/Oracle.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0 <0.8.0;
/// @title Oracle
/// @notice Provides price and liquidity data useful for a wide variety of system designs
/// @dev Instances of stored oracle data, "observations", are collected in the oracle array
/// Every pool is initialized with an oracle array length of 1. Anyone can pay the SSTOREs to increase the
/// maximum length of the oracle array. New slots will be added when the array is fully populated.
/// Observations are overwritten when the full length of the oracle array is populated.
/// The most recent observation is available, independent of the length of the oracle array, by passing 0 to observe()
library Oracle {
struct Observation {
// the block timestamp of the observation
uint32 blockTimestamp;
// the tick accumulator, i.e. tick * time elapsed since the pool was first initialized
int56 tickCumulative;
// the seconds per liquidity, i.e. seconds elapsed / max(1, liquidity) since the pool was first initialized
uint160 secondsPerLiquidityCumulativeX128;
// whether or not the observation is initialized
bool initialized;
}
/// @notice Transforms a previous observation into a new observation, given the passage of time and the current tick and liquidity values
/// @dev blockTimestamp _must_ be chronologically equal to or greater than last.blockTimestamp, safe for 0 or 1 overflows
/// @param last The specified observation to be transformed
/// @param blockTimestamp The timestamp of the new observation
/// @param tick The active tick at the time of the new observation
/// @param liquidity The total in-range liquidity at the time of the new observation
/// @return Observation The newly populated observation
function transform(
Observation memory last,
uint32 blockTimestamp,
int24 tick,
uint128 liquidity
) private pure returns (Observation memory) {
uint32 delta = blockTimestamp - last.blockTimestamp;
return
Observation({
blockTimestamp: blockTimestamp,
tickCumulative: last.tickCumulative + int56(tick) * delta,
secondsPerLiquidityCumulativeX128: last.secondsPerLiquidityCumulativeX128 +
((uint160(delta) << 128) / (liquidity > 0 ? liquidity : 1)),
initialized: true
});
}
/// @notice Initialize the oracle array by writing the first slot. Called once for the lifecycle of the observations array
/// @param self The stored oracle array
/// @param time The time of the oracle initialization, via block.timestamp truncated to uint32
/// @return cardinality The number of populated elements in the oracle array
/// @return cardinalityNext The new length of the oracle array, independent of population
function initialize(Observation[65535] storage self, uint32 time)
internal
returns (uint16 cardinality, uint16 cardinalityNext)
{
self[0] = Observation({
blockTimestamp: time,
tickCumulative: 0,
secondsPerLiquidityCumulativeX128: 0,
initialized: true
});
return (1, 1);
}
/// @notice Writes an oracle observation to the array
/// @dev Writable at most once per block. Index represents the most recently written element. cardinality and index must be tracked externally.
/// If the index is at the end of the allowable array length (according to cardinality), and the next cardinality
/// is greater than the current one, cardinality may be increased. This restriction is created to preserve ordering.
/// @param self The stored oracle array
/// @param index The index of the observation that was most recently written to the observations array
/// @param blockTimestamp The timestamp of the new observation
/// @param tick The active tick at the time of the new observation
/// @param liquidity The total in-range liquidity at the time of the new observation
/// @param cardinality The number of populated elements in the oracle array
/// @param cardinalityNext The new length of the oracle array, independent of population
/// @return indexUpdated The new index of the most recently written element in the oracle array
/// @return cardinalityUpdated The new cardinality of the oracle array
function write(
Observation[65535] storage self,
uint16 index,
uint32 blockTimestamp,
int24 tick,
uint128 liquidity,
uint16 cardinality,
uint16 cardinalityNext
) internal returns (uint16 indexUpdated, uint16 cardinalityUpdated) {
Observation memory last = self[index];
// early return if we've already written an observation this block
if (last.blockTimestamp == blockTimestamp) return (index, cardinality);
// if the conditions are right, we can bump the cardinality
if (cardinalityNext > cardinality && index == (cardinality - 1)) {
cardinalityUpdated = cardinalityNext;
} else {
cardinalityUpdated = cardinality;
}
indexUpdated = (index + 1) % cardinalityUpdated;
self[indexUpdated] = transform(last, blockTimestamp, tick, liquidity);
}
/// @notice Prepares the oracle array to store up to `next` observations
/// @param self The stored oracle array
/// @param current The current next cardinality of the oracle array
/// @param next The proposed next cardinality which will be populated in the oracle array
/// @return next The next cardinality which will be populated in the oracle array
function grow(
Observation[65535] storage self,
uint16 current,
uint16 next
) internal returns (uint16) {
require(current > 0, 'I');
// no-op if the passed next value isn't greater than the current next value
if (next <= current) return current;
// store in each slot to prevent fresh SSTOREs in swaps
// this data will not be used because the initialized boolean is still false
for (uint16 i = current; i < next; i++) self[i].blockTimestamp = 1;
return next;
}
/// @notice comparator for 32-bit timestamps
/// @dev safe for 0 or 1 overflows, a and b _must_ be chronologically before or equal to time
/// @param time A timestamp truncated to 32 bits
/// @param a A comparison timestamp from which to determine the relative position of `time`
/// @param b From which to determine the relative position of `time`
/// @return bool Whether `a` is chronologically <= `b`
function lte(
uint32 time,
uint32 a,
uint32 b
) private pure returns (bool) {
// if there hasn't been overflow, no need to adjust
if (a <= time && b <= time) return a <= b;
uint256 aAdjusted = a > time ? a : a + 2**32;
uint256 bAdjusted = b > time ? b : b + 2**32;
return aAdjusted <= bAdjusted;
}
/// @notice Fetches the observations beforeOrAt and atOrAfter a target, i.e. where [beforeOrAt, atOrAfter] is satisfied.
/// The result may be the same observation, or adjacent observations.
/// @dev The answer must be contained in the array, used when the target is located within the stored observation
/// boundaries: older than the most recent observation and younger, or the same age as, the oldest observation
/// @param self The stored oracle array
/// @param time The current block.timestamp
/// @param target The timestamp at which the reserved observation should be for
/// @param index The index of the observation that was most recently written to the observations array
/// @param cardinality The number of populated elements in the oracle array
/// @return beforeOrAt The observation recorded before, or at, the target
/// @return atOrAfter The observation recorded at, or after, the target
function binarySearch(
Observation[65535] storage self,
uint32 time,
uint32 target,
uint16 index,
uint16 cardinality
) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
uint256 l = (index + 1) % cardinality; // oldest observation
uint256 r = l + cardinality - 1; // newest observation
uint256 i;
while (true) {
i = (l + r) / 2;
beforeOrAt = self[i % cardinality];
// we've landed on an uninitialized tick, keep searching higher (more recently)
if (!beforeOrAt.initialized) {
l = i + 1;
continue;
}
atOrAfter = self[(i + 1) % cardinality];
bool targetAtOrAfter = lte(time, beforeOrAt.blockTimestamp, target);
// check if we've found the answer!
if (targetAtOrAfter && lte(time, target, atOrAfter.blockTimestamp)) break;
if (!targetAtOrAfter) r = i - 1;
else l = i + 1;
}
}
/// @notice Fetches the observations beforeOrAt and atOrAfter a given target, i.e. where [beforeOrAt, atOrAfter] is satisfied
/// @dev Assumes there is at least 1 initialized observation.
/// Used by observeSingle() to compute the counterfactual accumulator values as of a given block timestamp.
/// @param self The stored oracle array
/// @param time The current block.timestamp
/// @param target The timestamp at which the reserved observation should be for
/// @param tick The active tick at the time of the returned or simulated observation
/// @param index The index of the observation that was most recently written to the observations array
/// @param liquidity The total pool liquidity at the time of the call
/// @param cardinality The number of populated elements in the oracle array
/// @return beforeOrAt The observation which occurred at, or before, the given timestamp
/// @return atOrAfter The observation which occurred at, or after, the given timestamp
function getSurroundingObservations(
Observation[65535] storage self,
uint32 time,
uint32 target,
int24 tick,
uint16 index,
uint128 liquidity,
uint16 cardinality
) private view returns (Observation memory beforeOrAt, Observation memory atOrAfter) {
// optimistically set before to the newest observation
beforeOrAt = self[index];
// if the target is chronologically at or after the newest observation, we can early return
if (lte(time, beforeOrAt.blockTimestamp, target)) {
if (beforeOrAt.blockTimestamp == target) {
// if newest observation equals target, we're in the same block, so we can ignore atOrAfter
return (beforeOrAt, atOrAfter);
} else {
// otherwise, we need to transform
return (beforeOrAt, transform(beforeOrAt, target, tick, liquidity));
}
}
// now, set before to the oldest observation
beforeOrAt = self[(index + 1) % cardinality];
if (!beforeOrAt.initialized) beforeOrAt = self[0];
// ensure that the target is chronologically at or after the oldest observation
require(lte(time, beforeOrAt.blockTimestamp, target), 'OLD');
// if we've reached this point, we have to binary search
return binarySearch(self, time, target, index, cardinality);
}
/// @dev Reverts if an observation at or before the desired observation timestamp does not exist.
/// 0 may be passed as `secondsAgo' to return the current cumulative values.
/// If called with a timestamp falling between two observations, returns the counterfactual accumulator values
/// at exactly the timestamp between the two observations.
/// @param self The stored oracle array
/// @param time The current block timestamp
/// @param secondsAgo The amount of time to look back, in seconds, at which point to return an observation
/// @param tick The current tick
/// @param index The index of the observation that was most recently written to the observations array
/// @param liquidity The current in-range pool liquidity
/// @param cardinality The number of populated elements in the oracle array
/// @return tickCumulative The tick * time elapsed since the pool was first initialized, as of `secondsAgo`
/// @return secondsPerLiquidityCumulativeX128 The time elapsed / max(1, liquidity) since the pool was first initialized, as of `secondsAgo`
function observeSingle(
Observation[65535] storage self,
uint32 time,
uint32 secondsAgo,
int24 tick,
uint16 index,
uint128 liquidity,
uint16 cardinality
) internal view returns (int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128) {
if (secondsAgo == 0) {
Observation memory last = self[index];
if (last.blockTimestamp != time) last = transform(last, time, tick, liquidity);
return (last.tickCumulative, last.secondsPerLiquidityCumulativeX128);
}
uint32 target = time - secondsAgo;
(Observation memory beforeOrAt, Observation memory atOrAfter) =
getSurroundingObservations(self, time, target, tick, index, liquidity, cardinality);
if (target == beforeOrAt.blockTimestamp) {
// we're at the left boundary
return (beforeOrAt.tickCumulative, beforeOrAt.secondsPerLiquidityCumulativeX128);
} else if (target == atOrAfter.blockTimestamp) {
// we're at the right boundary
return (atOrAfter.tickCumulative, atOrAfter.secondsPerLiquidityCumulativeX128);
} else {
// we're in the middle
uint32 observationTimeDelta = atOrAfter.blockTimestamp - beforeOrAt.blockTimestamp;
uint32 targetDelta = target - beforeOrAt.blockTimestamp;
return (
beforeOrAt.tickCumulative +
((atOrAfter.tickCumulative - beforeOrAt.tickCumulative) / observationTimeDelta) *
targetDelta,
beforeOrAt.secondsPerLiquidityCumulativeX128 +
uint160(
(uint256(
atOrAfter.secondsPerLiquidityCumulativeX128 - beforeOrAt.secondsPerLiquidityCumulativeX128
) * targetDelta) / observationTimeDelta
)
);
}
}
/// @notice Returns the accumulator values as of each time seconds ago from the given time in the array of `secondsAgos`
/// @dev Reverts if `secondsAgos` > oldest observation
/// @param self The stored oracle array
/// @param time The current block.timestamp
/// @param secondsAgos Each amount of time to look back, in seconds, at which point to return an observation
/// @param tick The current tick
/// @param index The index of the observation that was most recently written to the observations array
/// @param liquidity The current in-range pool liquidity
/// @param cardinality The number of populated elements in the oracle array
/// @return tickCumulatives The tick * time elapsed since the pool was first initialized, as of each `secondsAgo`
/// @return secondsPerLiquidityCumulativeX128s The cumulative seconds / max(1, liquidity) since the pool was first initialized, as of each `secondsAgo`
function observe(
Observation[65535] storage self,
uint32 time,
uint32[] memory secondsAgos,
int24 tick,
uint16 index,
uint128 liquidity,
uint16 cardinality
) internal view returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s) {
require(cardinality > 0, 'I');
tickCumulatives = new int56[](secondsAgos.length);
secondsPerLiquidityCumulativeX128s = new uint160[](secondsAgos.length);
for (uint256 i = 0; i < secondsAgos.length; i++) {
(tickCumulatives[i], secondsPerLiquidityCumulativeX128s[i]) = observeSingle(
self,
time,
secondsAgos[i],
tick,
index,
liquidity,
cardinality
);
}
}
}
contracts/libraries/Position.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0 <0.8.0;
import './FullMath.sol';
import './FixedPoint128.sol';
import './LiquidityMath.sol';
/// @title Position
/// @notice Positions represent an owner address' liquidity between a lower and upper tick boundary
/// @dev Positions store additional state for tracking fees owed to the position
library Position {
// info stored for each user's position
struct Info {
// the amount of liquidity owned by this position
uint128 liquidity;
// fee growth per unit of liquidity as of the last update to liquidity or fees owed
uint256 feeGrowthInside0LastX128;
uint256 feeGrowthInside1LastX128;
// the fees owed to the position owner in token0/token1
uint128 tokensOwed0;
uint128 tokensOwed1;
}
/// @notice Returns the Info struct of a position, given an owner and position boundaries
/// @param self The mapping containing all user positions
/// @param owner The address of the position owner
/// @param tickLower The lower tick boundary of the position
/// @param tickUpper The upper tick boundary of the position
/// @return position The position info struct of the given owners' position
function get(
mapping(bytes32 => Info) storage self,
address owner,
int24 tickLower,
int24 tickUpper
) internal view returns (Position.Info storage position) {
position = self[keccak256(abi.encodePacked(owner, tickLower, tickUpper))];
}
/// @notice Credits accumulated fees to a user's position
/// @param self The individual position to update
/// @param liquidityDelta The change in pool liquidity as a result of the position update
/// @param feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
/// @param feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
function update(
Info storage self,
int128 liquidityDelta,
uint256 feeGrowthInside0X128,
uint256 feeGrowthInside1X128
) internal {
Info memory _self = self;
uint128 liquidityNext;
if (liquidityDelta == 0) {
require(_self.liquidity > 0, 'NP'); // disallow pokes for 0 liquidity positions
liquidityNext = _self.liquidity;
} else {
liquidityNext = LiquidityMath.addDelta(_self.liquidity, liquidityDelta);
}
// calculate accumulated fees
uint128 tokensOwed0 =
uint128(
FullMath.mulDiv(
feeGrowthInside0X128 - _self.feeGrowthInside0LastX128,
_self.liquidity,
FixedPoint128.Q128
)
);
uint128 tokensOwed1 =
uint128(
FullMath.mulDiv(
feeGrowthInside1X128 - _self.feeGrowthInside1LastX128,
_self.liquidity,
FixedPoint128.Q128
)
);
// update the position
if (liquidityDelta != 0) self.liquidity = liquidityNext;
self.feeGrowthInside0LastX128 = feeGrowthInside0X128;
self.feeGrowthInside1LastX128 = feeGrowthInside1X128;
if (tokensOwed0 > 0 || tokensOwed1 > 0) {
// overflow is acceptable, have to withdraw before you hit type(uint128).max fees
self.tokensOwed0 += tokensOwed0;
self.tokensOwed1 += tokensOwed1;
}
}
}
contracts/libraries/SafeCast.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Safe casting methods
/// @notice Contains methods for safely casting between types
library SafeCast {
/// @notice Cast a uint256 to a uint160, revert on overflow
/// @param y The uint256 to be downcasted
/// @return z The downcasted integer, now type uint160
function toUint160(uint256 y) internal pure returns (uint160 z) {
require((z = uint160(y)) == y);
}
/// @notice Cast a int256 to a int128, revert on overflow or underflow
/// @param y The int256 to be downcasted
/// @return z The downcasted integer, now type int128
function toInt128(int256 y) internal pure returns (int128 z) {
require((z = int128(y)) == y);
}
/// @notice Cast a uint256 to a int256, revert on overflow
/// @param y The uint256 to be casted
/// @return z The casted integer, now type int256
function toInt256(uint256 y) internal pure returns (int256 z) {
require(y < 2**255);
z = int256(y);
}
}
contracts/libraries/SwapCache.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
struct SwapCache {
// the protocol fee for the input token
uint8 feeProtocol;
// liquidity at the beginning of the swap
uint128 liquidityStart;
// the timestamp of the current block
uint32 blockTimestamp;
// the current value of the tick accumulator, computed only if we cross an initialized tick
int56 tickCumulative;
// the current value of seconds per liquidity accumulator, computed only if we cross an initialized tick
uint160 secondsPerLiquidityCumulativeX128;
// whether we've computed and cached the above two accumulators
bool computedLatestObservation;
}
contracts/libraries/SwapMath.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './FullMath.sol';
import './SqrtPriceMath.sol';
/// @title Computes the result of a swap within ticks
/// @notice Contains methods for computing the result of a swap within a single tick price range, i.e., a single tick.
library SwapMath {
/// @notice Computes the result of swapping some amount in, or amount out, given the parameters of the swap
/// @dev The fee, plus the amount in, will never exceed the amount remaining if the swap's `amountSpecified` is positive
/// @param sqrtRatioCurrentX96 The current sqrt price of the pool
/// @param sqrtRatioTargetX96 The price that cannot be exceeded, from which the direction of the swap is inferred
/// @param liquidity The usable liquidity
/// @param amountRemaining How much input or output amount is remaining to be swapped in/out
/// @param feePips The fee taken from the input amount, expressed in hundredths of a bip
/// @return sqrtRatioNextX96 The price after swapping the amount in/out, not to exceed the price target
/// @return amountIn The amount to be swapped in, of either token0 or token1, based on the direction of the swap
/// @return amountOut The amount to be received, of either token0 or token1, based on the direction of the swap
/// @return feeAmount The amount of input that will be taken as a fee
function computeSwapStep(
uint160 sqrtRatioCurrentX96,
uint160 sqrtRatioTargetX96,
uint128 liquidity,
int256 amountRemaining,
uint24 feePips
)
internal
pure
returns (
uint160 sqrtRatioNextX96,
uint256 amountIn,
uint256 amountOut,
uint256 feeAmount
)
{
bool zeroForOne = sqrtRatioCurrentX96 >= sqrtRatioTargetX96;
bool exactIn = amountRemaining >= 0;
if (exactIn) {
uint256 amountRemainingLessFee = FullMath.mulDiv(uint256(amountRemaining), 1e6 - feePips, 1e6);
amountIn = zeroForOne
? SqrtPriceMath.getAmount0Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, true)
: SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, true);
if (amountRemainingLessFee >= amountIn) sqrtRatioNextX96 = sqrtRatioTargetX96;
else
sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromInput(
sqrtRatioCurrentX96,
liquidity,
amountRemainingLessFee,
zeroForOne
);
} else {
amountOut = zeroForOne
? SqrtPriceMath.getAmount1Delta(sqrtRatioTargetX96, sqrtRatioCurrentX96, liquidity, false)
: SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioTargetX96, liquidity, false);
if (uint256(-amountRemaining) >= amountOut) sqrtRatioNextX96 = sqrtRatioTargetX96;
else
sqrtRatioNextX96 = SqrtPriceMath.getNextSqrtPriceFromOutput(
sqrtRatioCurrentX96,
liquidity,
uint256(-amountRemaining),
zeroForOne
);
}
bool max = sqrtRatioTargetX96 == sqrtRatioNextX96;
// get the input/output amounts
if (zeroForOne) {
amountIn = max && exactIn
? amountIn
: SqrtPriceMath.getAmount0Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, true);
amountOut = max && !exactIn
? amountOut
: SqrtPriceMath.getAmount1Delta(sqrtRatioNextX96, sqrtRatioCurrentX96, liquidity, false);
} else {
amountIn = max && exactIn
? amountIn
: SqrtPriceMath.getAmount1Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, true);
amountOut = max && !exactIn
? amountOut
: SqrtPriceMath.getAmount0Delta(sqrtRatioCurrentX96, sqrtRatioNextX96, liquidity, false);
}
// cap the output amount to not exceed the remaining output amount
if (!exactIn && amountOut > uint256(-amountRemaining)) {
amountOut = uint256(-amountRemaining);
}
if (exactIn && sqrtRatioNextX96 != sqrtRatioTargetX96) {
// we didn't reach the target, so take the remainder of the maximum input as fee
feeAmount = uint256(amountRemaining) - amountIn;
} else {
feeAmount = FullMath.mulDivRoundingUp(amountIn, feePips, 1e6 - feePips);
}
}
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.7.6;
// the top level state of the swap, the results of which are recorded in storage at the end
struct SwapState {
// the amount remaining to be swapped in/out of the input/output asset
int256 amountSpecifiedRemaining;
// the amount already swapped out/in of the output/input asset
int256 amountCalculated;
// current sqrt(price)
uint160 sqrtPriceX96;
// the tick associated with the current price
int24 tick;
// the global fee growth of the input token
uint256 feeGrowthGlobalX128;
// amount of input token paid as protocol fee
uint128 protocolFee;
// the current liquidity in range
uint128 liquidity;
}
contracts/libraries/Tick.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0 <0.8.0;
import './LowGasSafeMath.sol';
import './SafeCast.sol';
import './TickMath.sol';
import './LiquidityMath.sol';
/// @title Tick
/// @notice Contains functions for managing tick processes and relevant calculations
library Tick {
using LowGasSafeMath for int256;
using SafeCast for int256;
// info stored for each initialized individual tick
struct Info {
// the total position liquidity that references this tick
uint128 liquidityGross;
// amount of net liquidity added (subtracted) when tick is crossed from left to right (right to left),
int128 liquidityNet;
// fee growth per unit of liquidity on the _other_ side of this tick (relative to the current tick)
// only has relative meaning, not absolute — the value depends on when the tick is initialized
uint256 feeGrowthOutside0X128;
uint256 feeGrowthOutside1X128;
// the cumulative tick value on the other side of the tick
int56 tickCumulativeOutside;
// the seconds per unit of liquidity on the _other_ side of this tick (relative to the current tick)
// only has relative meaning, not absolute — the value depends on when the tick is initialized
uint160 secondsPerLiquidityOutsideX128;
// the seconds spent on the other side of the tick (relative to the current tick)
// only has relative meaning, not absolute — the value depends on when the tick is initialized
uint32 secondsOutside;
// true iff the tick is initialized, i.e. the value is exactly equivalent to the expression liquidityGross != 0
// these 8 bits are set to prevent fresh sstores when crossing newly initialized ticks
bool initialized;
}
/// @notice Derives max liquidity per tick from given tick spacing
/// @dev Executed within the pool constructor
/// @param tickSpacing The amount of required tick separation, realized in multiples of `tickSpacing`
/// e.g., a tickSpacing of 3 requires ticks to be initialized every 3rd tick i.e., ..., -6, -3, 0, 3, 6, ...
/// @return The max liquidity per tick
function tickSpacingToMaxLiquidityPerTick(int24 tickSpacing) internal pure returns (uint128) {
int24 minTick = (TickMath.MIN_TICK / tickSpacing) * tickSpacing;
int24 maxTick = (TickMath.MAX_TICK / tickSpacing) * tickSpacing;
uint24 numTicks = uint24((maxTick - minTick) / tickSpacing) + 1;
return type(uint128).max / numTicks;
}
/// @notice Retrieves fee growth data
/// @param self The mapping containing all tick information for initialized ticks
/// @param tickLower The lower tick boundary of the position
/// @param tickUpper The upper tick boundary of the position
/// @param tickCurrent The current tick
/// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
/// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
/// @return feeGrowthInside0X128 The all-time fee growth in token0, per unit of liquidity, inside the position's tick boundaries
/// @return feeGrowthInside1X128 The all-time fee growth in token1, per unit of liquidity, inside the position's tick boundaries
function getFeeGrowthInside(
mapping(int24 => Tick.Info) storage self,
int24 tickLower,
int24 tickUpper,
int24 tickCurrent,
uint256 feeGrowthGlobal0X128,
uint256 feeGrowthGlobal1X128
) internal view returns (uint256 feeGrowthInside0X128, uint256 feeGrowthInside1X128) {
Info storage lower = self[tickLower];
Info storage upper = self[tickUpper];
// calculate fee growth below
uint256 feeGrowthBelow0X128;
uint256 feeGrowthBelow1X128;
if (tickCurrent >= tickLower) {
feeGrowthBelow0X128 = lower.feeGrowthOutside0X128;
feeGrowthBelow1X128 = lower.feeGrowthOutside1X128;
} else {
feeGrowthBelow0X128 = feeGrowthGlobal0X128 - lower.feeGrowthOutside0X128;
feeGrowthBelow1X128 = feeGrowthGlobal1X128 - lower.feeGrowthOutside1X128;
}
// calculate fee growth above
uint256 feeGrowthAbove0X128;
uint256 feeGrowthAbove1X128;
if (tickCurrent < tickUpper) {
feeGrowthAbove0X128 = upper.feeGrowthOutside0X128;
feeGrowthAbove1X128 = upper.feeGrowthOutside1X128;
} else {
feeGrowthAbove0X128 = feeGrowthGlobal0X128 - upper.feeGrowthOutside0X128;
feeGrowthAbove1X128 = feeGrowthGlobal1X128 - upper.feeGrowthOutside1X128;
}
feeGrowthInside0X128 = feeGrowthGlobal0X128 - feeGrowthBelow0X128 - feeGrowthAbove0X128;
feeGrowthInside1X128 = feeGrowthGlobal1X128 - feeGrowthBelow1X128 - feeGrowthAbove1X128;
}
/// @notice Updates a tick and returns true if the tick was flipped from initialized to uninitialized, or vice versa
/// @param self The mapping containing all tick information for initialized ticks
/// @param tick The tick that will be updated
/// @param tickCurrent The current tick
/// @param liquidityDelta A new amount of liquidity to be added (subtracted) when tick is crossed from left to right (right to left)
/// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
/// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
/// @param secondsPerLiquidityCumulativeX128 The all-time seconds per max(1, liquidity) of the pool
/// @param tickCumulative The tick * time elapsed since the pool was first initialized
/// @param time The current block timestamp cast to a uint32
/// @param upper true for updating a position's upper tick, or false for updating a position's lower tick
/// @param maxLiquidity The maximum liquidity allocation for a single tick
/// @return flipped Whether the tick was flipped from initialized to uninitialized, or vice versa
function update(
mapping(int24 => Tick.Info) storage self,
int24 tick,
int24 tickCurrent,
int128 liquidityDelta,
uint256 feeGrowthGlobal0X128,
uint256 feeGrowthGlobal1X128,
uint160 secondsPerLiquidityCumulativeX128,
int56 tickCumulative,
uint32 time,
bool upper,
uint128 maxLiquidity
) internal returns (bool flipped) {
Tick.Info storage info = self[tick];
uint128 liquidityGrossBefore = info.liquidityGross;
uint128 liquidityGrossAfter = LiquidityMath.addDelta(liquidityGrossBefore, liquidityDelta);
require(liquidityGrossAfter <= maxLiquidity, 'LO');
flipped = (liquidityGrossAfter == 0) != (liquidityGrossBefore == 0);
if (liquidityGrossBefore == 0) {
// by convention, we assume that all growth before a tick was initialized happened _below_ the tick
if (tick <= tickCurrent) {
info.feeGrowthOutside0X128 = feeGrowthGlobal0X128;
info.feeGrowthOutside1X128 = feeGrowthGlobal1X128;
info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128;
info.tickCumulativeOutside = tickCumulative;
info.secondsOutside = time;
}
info.initialized = true;
}
info.liquidityGross = liquidityGrossAfter;
// when the lower (upper) tick is crossed left to right (right to left), liquidity must be added (removed)
info.liquidityNet = upper
? int256(info.liquidityNet).sub(liquidityDelta).toInt128()
: int256(info.liquidityNet).add(liquidityDelta).toInt128();
}
/// @notice Clears tick data
/// @param self The mapping containing all initialized tick information for initialized ticks
/// @param tick The tick that will be cleared
function clear(mapping(int24 => Tick.Info) storage self, int24 tick) internal {
delete self[tick];
}
/// @notice Transitions to next tick as needed by price movement
/// @param self The mapping containing all tick information for initialized ticks
/// @param tick The destination tick of the transition
/// @param feeGrowthGlobal0X128 The all-time global fee growth, per unit of liquidity, in token0
/// @param feeGrowthGlobal1X128 The all-time global fee growth, per unit of liquidity, in token1
/// @param secondsPerLiquidityCumulativeX128 The current seconds per liquidity
/// @param tickCumulative The tick * time elapsed since the pool was first initialized
/// @param time The current block.timestamp
/// @return liquidityNet The amount of liquidity added (subtracted) when tick is crossed from left to right (right to left)
function cross(
mapping(int24 => Tick.Info) storage self,
int24 tick,
uint256 feeGrowthGlobal0X128,
uint256 feeGrowthGlobal1X128,
uint160 secondsPerLiquidityCumulativeX128,
int56 tickCumulative,
uint32 time
) internal returns (int128 liquidityNet) {
Tick.Info storage info = self[tick];
info.feeGrowthOutside0X128 = feeGrowthGlobal0X128 - info.feeGrowthOutside0X128;
info.feeGrowthOutside1X128 = feeGrowthGlobal1X128 - info.feeGrowthOutside1X128;
info.secondsPerLiquidityOutsideX128 = secondsPerLiquidityCumulativeX128 - info.secondsPerLiquidityOutsideX128;
info.tickCumulativeOutside = tickCumulative - info.tickCumulativeOutside;
info.secondsOutside = time - info.secondsOutside;
liquidityNet = info.liquidityNet;
}
}
contracts/libraries/TickBitmap.sol
// SPDX-License-Identifier: BUSL-1.1
pragma solidity >=0.5.0;
import './BitMath.sol';
/// @title Packed tick initialized state library
/// @notice Stores a packed mapping of tick index to its initialized state
/// @dev The mapping uses int16 for keys since ticks are represented as int24 and there are 256 (2^8) values per word.
library TickBitmap {
/// @notice Computes the position in the mapping where the initialized bit for a tick lives
/// @param tick The tick for which to compute the position
/// @return wordPos The key in the mapping containing the word in which the bit is stored
/// @return bitPos The bit position in the word where the flag is stored
function position(int24 tick) private pure returns (int16 wordPos, uint8 bitPos) {
wordPos = int16(tick >> 8);
bitPos = uint8(tick % 256);
}
/// @notice Flips the initialized state for a given tick from false to true, or vice versa
/// @param self The mapping in which to flip the tick
/// @param tick The tick to flip
/// @param tickSpacing The spacing between usable ticks
function flipTick(
mapping(int16 => uint256) storage self,
int24 tick,
int24 tickSpacing
) internal {
require(tick % tickSpacing == 0); // ensure that the tick is spaced
(int16 wordPos, uint8 bitPos) = position(tick / tickSpacing);
uint256 mask = 1 << bitPos;
self[wordPos] ^= mask;
}
/// @notice Returns the next initialized tick contained in the same word (or adjacent word) as the tick that is either
/// to the left (less than or equal to) or right (greater than) of the given tick
/// @param self The mapping in which to compute the next initialized tick
/// @param tick The starting tick
/// @param tickSpacing The spacing between usable ticks
/// @param lte Whether to search for the next initialized tick to the left (less than or equal to the starting tick)
/// @return next The next initialized or uninitialized tick up to 256 ticks away from the current tick
/// @return initialized Whether the next tick is initialized, as the function only searches within up to 256 ticks
function nextInitializedTickWithinOneWord(
mapping(int16 => uint256) storage self,
int24 tick,
int24 tickSpacing,
bool lte
) internal view returns (int24 next, bool initialized) {
int24 compressed = tick / tickSpacing;
if (tick < 0 && tick % tickSpacing != 0) compressed--; // round towards negative infinity
if (lte) {
(int16 wordPos, uint8 bitPos) = position(compressed);
// all the 1s at or to the right of the current bitPos
uint256 mask = (1 << bitPos) - 1 + (1 << bitPos);
uint256 masked = self[wordPos] & mask;
// if there are no initialized ticks to the right of or at the current tick, return rightmost in the word
initialized = masked != 0;
// overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
next = initialized
? (compressed - int24(bitPos - BitMath.mostSignificantBit(masked))) * tickSpacing
: (compressed - int24(bitPos)) * tickSpacing;
} else {
// start from the word of the next tick, since the current tick state doesn't matter
(int16 wordPos, uint8 bitPos) = position(compressed + 1);
// all the 1s at or to the left of the bitPos
uint256 mask = ~((1 << bitPos) - 1);
uint256 masked = self[wordPos] & mask;
// if there are no initialized ticks to the left of the current tick, return leftmost in the word
initialized = masked != 0;
// overflow/underflow is possible, but prevented externally by limiting both tickSpacing and tick
next = initialized
? (compressed + 1 + int24(BitMath.leastSignificantBit(masked) - bitPos)) * tickSpacing
: (compressed + 1 + int24(type(uint8).max - bitPos)) * tickSpacing;
}
}
}
contracts/libraries/TickMath.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0 <0.8.0;
/// @title Math library for computing sqrt prices from ticks and vice versa
/// @notice Computes sqrt price for ticks of size 1.0001, i.e. sqrt(1.0001^tick) as fixed point Q64.96 numbers. Supports
/// prices between 2**-128 and 2**128
library TickMath {
/// @dev The minimum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**-128
int24 internal constant MIN_TICK = -887272;
/// @dev The maximum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**128
int24 internal constant MAX_TICK = -MIN_TICK;
/// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
uint160 internal constant MIN_SQRT_RATIO = 4295128739;
/// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;
/// @notice Calculates sqrt(1.0001^tick) * 2^96
/// @dev Throws if |tick| > max tick
/// @param tick The input tick for the above formula
/// @return sqrtPriceX96 A Fixed point Q64.96 number representing the sqrt of the ratio of the two assets (token1/token0)
/// at the given tick
function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 sqrtPriceX96) {
uint256 absTick = tick < 0 ? uint256(-int256(tick)) : uint256(int256(tick));
require(absTick <= uint256(MAX_TICK), 'T');
uint256 ratio = absTick & 0x1 != 0 ? 0xfffcb933bd6fad37aa2d162d1a594001 : 0x100000000000000000000000000000000;
if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;
if (tick > 0) ratio = type(uint256).max / ratio;
// this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
// we then downcast because we know the result always fits within 160 bits due to our tick input constraint
// we round up in the division so getTickAtSqrtRatio of the output price is always consistent
sqrtPriceX96 = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
}
/// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
/// @dev Throws in case sqrtPriceX96 < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
/// ever return.
/// @param sqrtPriceX96 The sqrt ratio for which to compute the tick as a Q64.96
/// @return tick The greatest tick for which the ratio is less than or equal to the input ratio
function getTickAtSqrtRatio(uint160 sqrtPriceX96) internal pure returns (int24 tick) {
// second inequality must be < because the price can never reach the price at the max tick
require(sqrtPriceX96 >= MIN_SQRT_RATIO && sqrtPriceX96 < MAX_SQRT_RATIO, 'R');
uint256 ratio = uint256(sqrtPriceX96) << 32;
uint256 r = ratio;
uint256 msb = 0;
assembly {
let f := shl(7, gt(r, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := shl(6, gt(r, 0xFFFFFFFFFFFFFFFF))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := shl(5, gt(r, 0xFFFFFFFF))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := shl(4, gt(r, 0xFFFF))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := shl(3, gt(r, 0xFF))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := shl(2, gt(r, 0xF))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := shl(1, gt(r, 0x3))
msb := or(msb, f)
r := shr(f, r)
}
assembly {
let f := gt(r, 0x1)
msb := or(msb, f)
}
if (msb >= 128) r = ratio >> (msb - 127);
else r = ratio << (127 - msb);
int256 log_2 = (int256(msb) - 128) << 64;
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(63, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(62, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(61, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(60, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(59, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(58, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(57, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(56, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(55, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(54, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(53, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(52, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(51, f))
r := shr(f, r)
}
assembly {
r := shr(127, mul(r, r))
let f := shr(128, r)
log_2 := or(log_2, shl(50, f))
}
int256 log_sqrt10001 = log_2 * 255738958999603826347141; // 128.128 number
int24 tickLow = int24((log_sqrt10001 - 3402992956809132418596140100660247210) >> 128);
int24 tickHi = int24((log_sqrt10001 + 291339464771989622907027621153398088495) >> 128);
tick = tickLow == tickHi ? tickLow : getSqrtRatioAtTick(tickHi) <= sqrtPriceX96 ? tickHi : tickLow;
}
}
contracts/libraries/TransferHelper.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.6.0;
import '../interfaces/IERC20Minimal.sol';
/// @title TransferHelper
/// @notice Contains helper methods for interacting with ERC20 tokens that do not consistently return true/false
library TransferHelper {
/// @notice Transfers tokens from msg.sender to a recipient
/// @dev Calls transfer on token contract, errors with TF if transfer fails
/// @param token The contract address of the token which will be transferred
/// @param to The recipient of the transfer
/// @param value The value of the transfer
function safeTransfer(
address token,
address to,
uint256 value
) internal {
(bool success, bytes memory data) =
token.call(abi.encodeWithSelector(IERC20Minimal.transfer.selector, to, value));
require(success && (data.length == 0 || abi.decode(data, (bool))), 'TF');
}
}
contracts/libraries/UnsafeMath.sol
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
/// @title Math functions that do not check inputs or outputs
/// @notice Contains methods that perform common math functions but do not do any overflow or underflow checks
library UnsafeMath {
/// @notice Returns ceil(x / y)
/// @dev division by 0 has unspecified behavior, and must be checked externally
/// @param x The dividend
/// @param y The divisor
/// @return z The quotient, ceil(x / y)
function divRoundingUp(uint256 x, uint256 y) internal pure returns (uint256 z) {
assembly {
z := add(div(x, y), gt(mod(x, y), 0))
}
}
}
