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Comet.sol
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Comet.sol
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// SPDX-License-Identifier: BUSL-1.1
pragma solidity 0.8.15;
import "./CometMainInterface.sol";
import "./IERC20NonStandard.sol";
import "./IPriceFeed.sol";
/**
* @title Compound's Comet Contract
* @notice An efficient monolithic money market protocol
* @author Compound
*/
contract Comet is CometMainInterface {
/** General configuration constants **/
/// @notice The admin of the protocol
address public override immutable governor;
/// @notice The account which may trigger pauses
address public override immutable pauseGuardian;
/// @notice The address of the base token contract
address public override immutable baseToken;
/// @notice The address of the price feed for the base token
address public override immutable baseTokenPriceFeed;
/// @notice The address of the extension contract delegate
address public override immutable extensionDelegate;
/// @notice The point in the supply rates separating the low interest rate slope and the high interest rate slope (factor)
/// @dev uint64
uint public override immutable supplyKink;
/// @notice Per second supply interest rate slope applied when utilization is below kink (factor)
/// @dev uint64
uint public override immutable supplyPerSecondInterestRateSlopeLow;
/// @notice Per second supply interest rate slope applied when utilization is above kink (factor)
/// @dev uint64
uint public override immutable supplyPerSecondInterestRateSlopeHigh;
/// @notice Per second supply base interest rate (factor)
/// @dev uint64
uint public override immutable supplyPerSecondInterestRateBase;
/// @notice The point in the borrow rate separating the low interest rate slope and the high interest rate slope (factor)
/// @dev uint64
uint public override immutable borrowKink;
/// @notice Per second borrow interest rate slope applied when utilization is below kink (factor)
/// @dev uint64
uint public override immutable borrowPerSecondInterestRateSlopeLow;
/// @notice Per second borrow interest rate slope applied when utilization is above kink (factor)
/// @dev uint64
uint public override immutable borrowPerSecondInterestRateSlopeHigh;
/// @notice Per second borrow base interest rate (factor)
/// @dev uint64
uint public override immutable borrowPerSecondInterestRateBase;
/// @notice The fraction of the liquidation penalty that goes to buyers of collateral instead of the protocol
/// @dev uint64
uint public override immutable storeFrontPriceFactor;
/// @notice The scale for base token (must be less than 18 decimals)
/// @dev uint64
uint public override immutable baseScale;
/// @notice The scale for reward tracking
/// @dev uint64
uint public override immutable trackingIndexScale;
/// @notice The speed at which supply rewards are tracked (in trackingIndexScale)
/// @dev uint64
uint public override immutable baseTrackingSupplySpeed;
/// @notice The speed at which borrow rewards are tracked (in trackingIndexScale)
/// @dev uint64
uint public override immutable baseTrackingBorrowSpeed;
/// @notice The minimum amount of base principal wei for rewards to accrue
/// @dev This must be large enough so as to prevent division by base wei from overflowing the 64 bit indices
/// @dev uint104
uint public override immutable baseMinForRewards;
/// @notice The minimum base amount required to initiate a borrow
uint public override immutable baseBorrowMin;
/// @notice The minimum base token reserves which must be held before collateral is hodled
uint public override immutable targetReserves;
/// @notice The number of decimals for wrapped base token
uint8 public override immutable decimals;
/// @notice The number of assets this contract actually supports
uint8 public override immutable numAssets;
/// @notice Factor to divide by when accruing rewards in order to preserve 6 decimals (i.e. baseScale / 1e6)
uint internal immutable accrualDescaleFactor;
/** Collateral asset configuration (packed) **/
uint256 internal immutable asset00_a;
uint256 internal immutable asset00_b;
uint256 internal immutable asset01_a;
uint256 internal immutable asset01_b;
uint256 internal immutable asset02_a;
uint256 internal immutable asset02_b;
uint256 internal immutable asset03_a;
uint256 internal immutable asset03_b;
uint256 internal immutable asset04_a;
uint256 internal immutable asset04_b;
uint256 internal immutable asset05_a;
uint256 internal immutable asset05_b;
uint256 internal immutable asset06_a;
uint256 internal immutable asset06_b;
uint256 internal immutable asset07_a;
uint256 internal immutable asset07_b;
uint256 internal immutable asset08_a;
uint256 internal immutable asset08_b;
uint256 internal immutable asset09_a;
uint256 internal immutable asset09_b;
uint256 internal immutable asset10_a;
uint256 internal immutable asset10_b;
uint256 internal immutable asset11_a;
uint256 internal immutable asset11_b;
/**
* @notice Construct a new protocol instance
* @param config The mapping of initial/constant parameters
**/
constructor(Configuration memory config) {
// Sanity checks
uint8 decimals_ = IERC20NonStandard(config.baseToken).decimals();
if (decimals_ > MAX_BASE_DECIMALS) revert BadDecimals();
if (config.storeFrontPriceFactor > FACTOR_SCALE) revert BadDiscount();
if (config.assetConfigs.length > MAX_ASSETS) revert TooManyAssets();
if (config.baseMinForRewards == 0) revert BadMinimum();
if (IPriceFeed(config.baseTokenPriceFeed).decimals() != PRICE_FEED_DECIMALS) revert BadDecimals();
// Copy configuration
unchecked {
governor = config.governor;
pauseGuardian = config.pauseGuardian;
baseToken = config.baseToken;
baseTokenPriceFeed = config.baseTokenPriceFeed;
extensionDelegate = config.extensionDelegate;
storeFrontPriceFactor = config.storeFrontPriceFactor;
decimals = decimals_;
baseScale = uint64(10 ** decimals_);
trackingIndexScale = config.trackingIndexScale;
if (baseScale < BASE_ACCRUAL_SCALE) revert BadDecimals();
accrualDescaleFactor = baseScale / BASE_ACCRUAL_SCALE;
baseMinForRewards = config.baseMinForRewards;
baseTrackingSupplySpeed = config.baseTrackingSupplySpeed;
baseTrackingBorrowSpeed = config.baseTrackingBorrowSpeed;
baseBorrowMin = config.baseBorrowMin;
targetReserves = config.targetReserves;
}
// Set interest rate model configs
unchecked {
supplyKink = config.supplyKink;
supplyPerSecondInterestRateSlopeLow = config.supplyPerYearInterestRateSlopeLow / SECONDS_PER_YEAR;
supplyPerSecondInterestRateSlopeHigh = config.supplyPerYearInterestRateSlopeHigh / SECONDS_PER_YEAR;
supplyPerSecondInterestRateBase = config.supplyPerYearInterestRateBase / SECONDS_PER_YEAR;
borrowKink = config.borrowKink;
borrowPerSecondInterestRateSlopeLow = config.borrowPerYearInterestRateSlopeLow / SECONDS_PER_YEAR;
borrowPerSecondInterestRateSlopeHigh = config.borrowPerYearInterestRateSlopeHigh / SECONDS_PER_YEAR;
borrowPerSecondInterestRateBase = config.borrowPerYearInterestRateBase / SECONDS_PER_YEAR;
}
// Set asset info
numAssets = uint8(config.assetConfigs.length);
(asset00_a, asset00_b) = getPackedAssetInternal(config.assetConfigs, 0);
(asset01_a, asset01_b) = getPackedAssetInternal(config.assetConfigs, 1);
(asset02_a, asset02_b) = getPackedAssetInternal(config.assetConfigs, 2);
(asset03_a, asset03_b) = getPackedAssetInternal(config.assetConfigs, 3);
(asset04_a, asset04_b) = getPackedAssetInternal(config.assetConfigs, 4);
(asset05_a, asset05_b) = getPackedAssetInternal(config.assetConfigs, 5);
(asset06_a, asset06_b) = getPackedAssetInternal(config.assetConfigs, 6);
(asset07_a, asset07_b) = getPackedAssetInternal(config.assetConfigs, 7);
(asset08_a, asset08_b) = getPackedAssetInternal(config.assetConfigs, 8);
(asset09_a, asset09_b) = getPackedAssetInternal(config.assetConfigs, 9);
(asset10_a, asset10_b) = getPackedAssetInternal(config.assetConfigs, 10);
(asset11_a, asset11_b) = getPackedAssetInternal(config.assetConfigs, 11);
}
/**
* @dev Prevents marked functions from being reentered
* Note: this restrict contracts from calling comet functions in their hooks.
* Doing so will cause the transaction to revert.
*/
modifier nonReentrant() {
nonReentrantBefore();
_;
nonReentrantAfter();
}
/**
* @dev Checks that the reentrancy flag is not set and then sets the flag
*/
function nonReentrantBefore() internal {
bytes32 slot = REENTRANCY_GUARD_FLAG_SLOT;
uint256 status;
assembly ("memory-safe") {
status := sload(slot)
}
if (status == REENTRANCY_GUARD_ENTERED) revert ReentrantCallBlocked();
assembly ("memory-safe") {
sstore(slot, REENTRANCY_GUARD_ENTERED)
}
}
/**
* @dev Unsets the reentrancy flag
*/
function nonReentrantAfter() internal {
bytes32 slot = REENTRANCY_GUARD_FLAG_SLOT;
uint256 status;
assembly ("memory-safe") {
sstore(slot, REENTRANCY_GUARD_NOT_ENTERED)
}
}
/**
* @notice Initialize storage for the contract
* @dev Can be used from constructor or proxy
*/
function initializeStorage() override external {
if (lastAccrualTime != 0) revert AlreadyInitialized();
// Initialize aggregates
lastAccrualTime = getNowInternal();
baseSupplyIndex = BASE_INDEX_SCALE;
baseBorrowIndex = BASE_INDEX_SCALE;
// Implicit initialization (not worth increasing contract size)
// trackingSupplyIndex = 0;
// trackingBorrowIndex = 0;
}
/**
* @dev Checks and gets the packed asset info for storage
*/
function getPackedAssetInternal(AssetConfig[] memory assetConfigs, uint i) internal view returns (uint256, uint256) {
AssetConfig memory assetConfig;
if (i < assetConfigs.length) {
assembly {
assetConfig := mload(add(add(assetConfigs, 0x20), mul(i, 0x20)))
}
} else {
return (0, 0);
}
address asset = assetConfig.asset;
address priceFeed = assetConfig.priceFeed;
uint8 decimals_ = assetConfig.decimals;
// Short-circuit if asset is nil
if (asset == address(0)) {
return (0, 0);
}
// Sanity check price feed and asset decimals
if (IPriceFeed(priceFeed).decimals() != PRICE_FEED_DECIMALS) revert BadDecimals();
if (IERC20NonStandard(asset).decimals() != decimals_) revert BadDecimals();
// Ensure collateral factors are within range
if (assetConfig.borrowCollateralFactor >= assetConfig.liquidateCollateralFactor) revert BorrowCFTooLarge();
if (assetConfig.liquidateCollateralFactor > MAX_COLLATERAL_FACTOR) revert LiquidateCFTooLarge();
unchecked {
// Keep 4 decimals for each factor
uint64 descale = FACTOR_SCALE / 1e4;
uint16 borrowCollateralFactor = uint16(assetConfig.borrowCollateralFactor / descale);
uint16 liquidateCollateralFactor = uint16(assetConfig.liquidateCollateralFactor / descale);
uint16 liquidationFactor = uint16(assetConfig.liquidationFactor / descale);
// Be nice and check descaled values are still within range
if (borrowCollateralFactor >= liquidateCollateralFactor) revert BorrowCFTooLarge();
// Keep whole units of asset for supply cap
uint64 supplyCap = uint64(assetConfig.supplyCap / (10 ** decimals_));
uint256 word_a = (uint160(asset) << 0 |
uint256(borrowCollateralFactor) << 160 |
uint256(liquidateCollateralFactor) << 176 |
uint256(liquidationFactor) << 192);
uint256 word_b = (uint160(priceFeed) << 0 |
uint256(decimals_) << 160 |
uint256(supplyCap) << 168);
return (word_a, word_b);
}
}
/**
* @notice Get the i-th asset info, according to the order they were passed in originally
* @param i The index of the asset info to get
* @return The asset info object
*/
function getAssetInfo(uint8 i) override public view returns (AssetInfo memory) {
if (i >= numAssets) revert BadAsset();
uint256 word_a;
uint256 word_b;
if (i == 0) {
word_a = asset00_a;
word_b = asset00_b;
} else if (i == 1) {
word_a = asset01_a;
word_b = asset01_b;
} else if (i == 2) {
word_a = asset02_a;
word_b = asset02_b;
} else if (i == 3) {
word_a = asset03_a;
word_b = asset03_b;
} else if (i == 4) {
word_a = asset04_a;
word_b = asset04_b;
} else if (i == 5) {
word_a = asset05_a;
word_b = asset05_b;
} else if (i == 6) {
word_a = asset06_a;
word_b = asset06_b;
} else if (i == 7) {
word_a = asset07_a;
word_b = asset07_b;
} else if (i == 8) {
word_a = asset08_a;
word_b = asset08_b;
} else if (i == 9) {
word_a = asset09_a;
word_b = asset09_b;
} else if (i == 10) {
word_a = asset10_a;
word_b = asset10_b;
} else if (i == 11) {
word_a = asset11_a;
word_b = asset11_b;
} else {
revert Absurd();
}
address asset = address(uint160(word_a & type(uint160).max));
uint64 rescale = FACTOR_SCALE / 1e4;
uint64 borrowCollateralFactor = uint64(((word_a >> 160) & type(uint16).max) * rescale);
uint64 liquidateCollateralFactor = uint64(((word_a >> 176) & type(uint16).max) * rescale);
uint64 liquidationFactor = uint64(((word_a >> 192) & type(uint16).max) * rescale);
address priceFeed = address(uint160(word_b & type(uint160).max));
uint8 decimals_ = uint8(((word_b >> 160) & type(uint8).max));
uint64 scale = uint64(10 ** decimals_);
uint128 supplyCap = uint128(((word_b >> 168) & type(uint64).max) * scale);
return AssetInfo({
offset: i,
asset: asset,
priceFeed: priceFeed,
scale: scale,
borrowCollateralFactor: borrowCollateralFactor,
liquidateCollateralFactor: liquidateCollateralFactor,
liquidationFactor: liquidationFactor,
supplyCap: supplyCap
});
}
/**
* @dev Determine index of asset that matches given address
*/
function getAssetInfoByAddress(address asset) override public view returns (AssetInfo memory) {
for (uint8 i = 0; i < numAssets; ) {
AssetInfo memory assetInfo = getAssetInfo(i);
if (assetInfo.asset == asset) {
return assetInfo;
}
unchecked { i++; }
}
revert BadAsset();
}
/**
* @return The current timestamp
**/
function getNowInternal() virtual internal view returns (uint40) {
if (block.timestamp >= 2**40) revert TimestampTooLarge();
return uint40(block.timestamp);
}
/**
* @dev Calculate accrued interest indices for base token supply and borrows
**/
function accruedInterestIndices(uint timeElapsed) internal view returns (uint64, uint64) {
uint64 baseSupplyIndex_ = baseSupplyIndex;
uint64 baseBorrowIndex_ = baseBorrowIndex;
if (timeElapsed > 0) {
uint utilization = getUtilization();
uint supplyRate = getSupplyRate(utilization);
uint borrowRate = getBorrowRate(utilization);
baseSupplyIndex_ += safe64(mulFactor(baseSupplyIndex_, supplyRate * timeElapsed));
baseBorrowIndex_ += safe64(mulFactor(baseBorrowIndex_, borrowRate * timeElapsed));
}
return (baseSupplyIndex_, baseBorrowIndex_);
}
/**
* @dev Accrue interest (and rewards) in base token supply and borrows
**/
function accrueInternal() internal {
uint40 now_ = getNowInternal();
uint timeElapsed = uint256(now_ - lastAccrualTime);
if (timeElapsed > 0) {
(baseSupplyIndex, baseBorrowIndex) = accruedInterestIndices(timeElapsed);
if (totalSupplyBase >= baseMinForRewards) {
trackingSupplyIndex += safe64(divBaseWei(baseTrackingSupplySpeed * timeElapsed, totalSupplyBase));
}
if (totalBorrowBase >= baseMinForRewards) {
trackingBorrowIndex += safe64(divBaseWei(baseTrackingBorrowSpeed * timeElapsed, totalBorrowBase));
}
lastAccrualTime = now_;
}
}
/**
* @notice Accrue interest and rewards for an account
**/
function accrueAccount(address account) override external {
accrueInternal();
UserBasic memory basic = userBasic[account];
updateBasePrincipal(account, basic, basic.principal);
}
/**
* @dev Note: Does not accrue interest first
* @param utilization The utilization to check the supply rate for
* @return The per second supply rate at `utilization`
*/
function getSupplyRate(uint utilization) override public view returns (uint64) {
if (utilization <= supplyKink) {
// interestRateBase + interestRateSlopeLow * utilization
return safe64(supplyPerSecondInterestRateBase + mulFactor(supplyPerSecondInterestRateSlopeLow, utilization));
} else {
// interestRateBase + interestRateSlopeLow * kink + interestRateSlopeHigh * (utilization - kink)
return safe64(supplyPerSecondInterestRateBase + mulFactor(supplyPerSecondInterestRateSlopeLow, supplyKink) + mulFactor(supplyPerSecondInterestRateSlopeHigh, (utilization - supplyKink)));
}
}
/**
* @dev Note: Does not accrue interest first
* @param utilization The utilization to check the borrow rate for
* @return The per second borrow rate at `utilization`
*/
function getBorrowRate(uint utilization) override public view returns (uint64) {
if (utilization <= borrowKink) {
// interestRateBase + interestRateSlopeLow * utilization
return safe64(borrowPerSecondInterestRateBase + mulFactor(borrowPerSecondInterestRateSlopeLow, utilization));
} else {
// interestRateBase + interestRateSlopeLow * kink + interestRateSlopeHigh * (utilization - kink)
return safe64(borrowPerSecondInterestRateBase + mulFactor(borrowPerSecondInterestRateSlopeLow, borrowKink) + mulFactor(borrowPerSecondInterestRateSlopeHigh, (utilization - borrowKink)));
}
}
/**
* @dev Note: Does not accrue interest first
* @return The utilization rate of the base asset
*/
function getUtilization() override public view returns (uint) {
uint totalSupply_ = presentValueSupply(baseSupplyIndex, totalSupplyBase);
uint totalBorrow_ = presentValueBorrow(baseBorrowIndex, totalBorrowBase);
if (totalSupply_ == 0) {
return 0;
} else {
return totalBorrow_ * FACTOR_SCALE / totalSupply_;
}
}
/**
* @notice Get the current price from a feed
* @param priceFeed The address of a price feed
* @return The price, scaled by `PRICE_SCALE`
*/
function getPrice(address priceFeed) override public view returns (uint256) {
(, int price, , , ) = IPriceFeed(priceFeed).latestRoundData();
if (price <= 0) revert BadPrice();
return uint256(price);
}
/**
* @notice Gets the total balance of protocol collateral reserves for an asset
* @dev Note: Reverts if collateral reserves are somehow negative, which should not be possible
* @param asset The collateral asset
*/
function getCollateralReserves(address asset) override public view returns (uint) {
return IERC20NonStandard(asset).balanceOf(address(this)) - totalsCollateral[asset].totalSupplyAsset;
}
/**
* @notice Gets the total amount of protocol reserves of the base asset
*/
function getReserves() override public view returns (int) {
(uint64 baseSupplyIndex_, uint64 baseBorrowIndex_) = accruedInterestIndices(getNowInternal() - lastAccrualTime);
uint balance = IERC20NonStandard(baseToken).balanceOf(address(this));
uint totalSupply_ = presentValueSupply(baseSupplyIndex_, totalSupplyBase);
uint totalBorrow_ = presentValueBorrow(baseBorrowIndex_, totalBorrowBase);
return signed256(balance) - signed256(totalSupply_) + signed256(totalBorrow_);
}
/**
* @notice Check whether an account has enough collateral to borrow
* @param account The address to check
* @return Whether the account is minimally collateralized enough to borrow
*/
function isBorrowCollateralized(address account) override public view returns (bool) {
int104 principal = userBasic[account].principal;
if (principal >= 0) {
return true;
}
uint16 assetsIn = userBasic[account].assetsIn;
int liquidity = signedMulPrice(
presentValue(principal),
getPrice(baseTokenPriceFeed),
uint64(baseScale)
);
for (uint8 i = 0; i < numAssets; ) {
if (isInAsset(assetsIn, i)) {
if (liquidity >= 0) {
return true;
}
AssetInfo memory asset = getAssetInfo(i);
uint newAmount = mulPrice(
userCollateral[account][asset.asset].balance,
getPrice(asset.priceFeed),
asset.scale
);
liquidity += signed256(mulFactor(
newAmount,
asset.borrowCollateralFactor
));
}
unchecked { i++; }
}
return liquidity >= 0;
}
/**
* @notice Check whether an account has enough collateral to not be liquidated
* @param account The address to check
* @return Whether the account is minimally collateralized enough to not be liquidated
*/
function isLiquidatable(address account) override public view returns (bool) {
int104 principal = userBasic[account].principal;
if (principal >= 0) {
return false;
}
uint16 assetsIn = userBasic[account].assetsIn;
int liquidity = signedMulPrice(
presentValue(principal),
getPrice(baseTokenPriceFeed),
uint64(baseScale)
);
for (uint8 i = 0; i < numAssets; ) {
if (isInAsset(assetsIn, i)) {
if (liquidity >= 0) {
return false;
}
AssetInfo memory asset = getAssetInfo(i);
uint newAmount = mulPrice(
userCollateral[account][asset.asset].balance,
getPrice(asset.priceFeed),
asset.scale
);
liquidity += signed256(mulFactor(
newAmount,
asset.liquidateCollateralFactor
));
}
unchecked { i++; }
}
return liquidity < 0;
}
/**
* @dev The change in principal broken into repay and supply amounts
*/
function repayAndSupplyAmount(int104 oldPrincipal, int104 newPrincipal) internal pure returns (uint104, uint104) {
// If the new principal is less than the old principal, then no amount has been repaid or supplied
if (newPrincipal < oldPrincipal) return (0, 0);
if (newPrincipal <= 0) {
return (uint104(newPrincipal - oldPrincipal), 0);
} else if (oldPrincipal >= 0) {
return (0, uint104(newPrincipal - oldPrincipal));
} else {
return (uint104(-oldPrincipal), uint104(newPrincipal));
}
}
/**
* @dev The change in principal broken into withdraw and borrow amounts
*/
function withdrawAndBorrowAmount(int104 oldPrincipal, int104 newPrincipal) internal pure returns (uint104, uint104) {
// If the new principal is greater than the old principal, then no amount has been withdrawn or borrowed
if (newPrincipal > oldPrincipal) return (0, 0);
if (newPrincipal >= 0) {
return (uint104(oldPrincipal - newPrincipal), 0);
} else if (oldPrincipal <= 0) {
return (0, uint104(oldPrincipal - newPrincipal));
} else {
return (uint104(oldPrincipal), uint104(-newPrincipal));
}
}
/**
* @notice Pauses different actions within Comet
* @param supplyPaused Boolean for pausing supply actions
* @param transferPaused Boolean for pausing transfer actions
* @param withdrawPaused Boolean for pausing withdraw actions
* @param absorbPaused Boolean for pausing absorb actions
* @param buyPaused Boolean for pausing buy actions
*/
function pause(
bool supplyPaused,
bool transferPaused,
bool withdrawPaused,
bool absorbPaused,
bool buyPaused
) override external {
if (msg.sender != governor && msg.sender != pauseGuardian) revert Unauthorized();
pauseFlags =
uint8(0) |
(toUInt8(supplyPaused) << PAUSE_SUPPLY_OFFSET) |
(toUInt8(transferPaused) << PAUSE_TRANSFER_OFFSET) |
(toUInt8(withdrawPaused) << PAUSE_WITHDRAW_OFFSET) |
(toUInt8(absorbPaused) << PAUSE_ABSORB_OFFSET) |
(toUInt8(buyPaused) << PAUSE_BUY_OFFSET);
emit PauseAction(supplyPaused, transferPaused, withdrawPaused, absorbPaused, buyPaused);
}
/**
* @return Whether or not supply actions are paused
*/
function isSupplyPaused() override public view returns (bool) {
return toBool(pauseFlags & (uint8(1) << PAUSE_SUPPLY_OFFSET));
}
/**
* @return Whether or not transfer actions are paused
*/
function isTransferPaused() override public view returns (bool) {
return toBool(pauseFlags & (uint8(1) << PAUSE_TRANSFER_OFFSET));
}
/**
* @return Whether or not withdraw actions are paused
*/
function isWithdrawPaused() override public view returns (bool) {
return toBool(pauseFlags & (uint8(1) << PAUSE_WITHDRAW_OFFSET));
}
/**
* @return Whether or not absorb actions are paused
*/
function isAbsorbPaused() override public view returns (bool) {
return toBool(pauseFlags & (uint8(1) << PAUSE_ABSORB_OFFSET));
}
/**
* @return Whether or not buy actions are paused
*/
function isBuyPaused() override public view returns (bool) {
return toBool(pauseFlags & (uint8(1) << PAUSE_BUY_OFFSET));
}
/**
* @dev Multiply a number by a factor
*/
function mulFactor(uint n, uint factor) internal pure returns (uint) {
return n * factor / FACTOR_SCALE;
}
/**
* @dev Divide a number by an amount of base
*/
function divBaseWei(uint n, uint baseWei) internal view returns (uint) {
return n * baseScale / baseWei;
}
/**
* @dev Multiply a `fromScale` quantity by a price, returning a common price quantity
*/
function mulPrice(uint n, uint price, uint64 fromScale) internal pure returns (uint) {
return n * price / fromScale;
}
/**
* @dev Multiply a signed `fromScale` quantity by a price, returning a common price quantity
*/
function signedMulPrice(int n, uint price, uint64 fromScale) internal pure returns (int) {
return n * signed256(price) / int256(uint256(fromScale));
}
/**
* @dev Divide a common price quantity by a price, returning a `toScale` quantity
*/
function divPrice(uint n, uint price, uint64 toScale) internal pure returns (uint) {
return n * toScale / price;
}
/**
* @dev Whether user has a non-zero balance of an asset, given assetsIn flags
*/
function isInAsset(uint16 assetsIn, uint8 assetOffset) internal pure returns (bool) {
return (assetsIn & (uint16(1) << assetOffset) != 0);
}
/**
* @dev Update assetsIn bit vector if user has entered or exited an asset
*/
function updateAssetsIn(
address account,
AssetInfo memory assetInfo,
uint128 initialUserBalance,
uint128 finalUserBalance
) internal {
if (initialUserBalance == 0 && finalUserBalance != 0) {
// set bit for asset
userBasic[account].assetsIn |= (uint16(1) << assetInfo.offset);
} else if (initialUserBalance != 0 && finalUserBalance == 0) {
// clear bit for asset
userBasic[account].assetsIn &= ~(uint16(1) << assetInfo.offset);
}
}
/**
* @dev Write updated principal to store and tracking participation
*/
function updateBasePrincipal(address account, UserBasic memory basic, int104 principalNew) internal {
int104 principal = basic.principal;
basic.principal = principalNew;
if (principal >= 0) {
uint indexDelta = uint256(trackingSupplyIndex - basic.baseTrackingIndex);
basic.baseTrackingAccrued += safe64(uint104(principal) * indexDelta / trackingIndexScale / accrualDescaleFactor);
} else {
uint indexDelta = uint256(trackingBorrowIndex - basic.baseTrackingIndex);
basic.baseTrackingAccrued += safe64(uint104(-principal) * indexDelta / trackingIndexScale / accrualDescaleFactor);
}
if (principalNew >= 0) {
basic.baseTrackingIndex = trackingSupplyIndex;
} else {
basic.baseTrackingIndex = trackingBorrowIndex;
}
userBasic[account] = basic;
}
/**
* @dev Safe ERC20 transfer in and returns the final amount transferred (taking into account any fees)
* @dev Note: Safely handles non-standard ERC-20 tokens that do not return a value. See here: https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/
function doTransferIn(address asset, address from, uint amount) internal returns (uint) {
uint256 preTransferBalance = IERC20NonStandard(asset).balanceOf(address(this));
IERC20NonStandard(asset).transferFrom(from, address(this), amount);
bool success;
assembly ("memory-safe") {
switch returndatasize()
case 0 { // This is a non-standard ERC-20
success := not(0) // set success to true
}
case 32 { // This is a compliant ERC-20
returndatacopy(0, 0, 32)
success := mload(0) // Set `success = returndata` of override external call
}
default { // This is an excessively non-compliant ERC-20, revert.
revert(0, 0)
}
}
if (!success) revert TransferInFailed();
return IERC20NonStandard(asset).balanceOf(address(this)) - preTransferBalance;
}
/**
* @dev Safe ERC20 transfer out
* @dev Note: Safely handles non-standard ERC-20 tokens that do not return a value. See here: https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
*/
function doTransferOut(address asset, address to, uint amount) internal {
IERC20NonStandard(asset).transfer(to, amount);
bool success;
assembly ("memory-safe") {
switch returndatasize()
case 0 { // This is a non-standard ERC-20
success := not(0) // set success to true
}
case 32 { // This is a compliant ERC-20
returndatacopy(0, 0, 32)
success := mload(0) // Set `success = returndata` of override external call
}
default { // This is an excessively non-compliant ERC-20, revert.
revert(0, 0)
}
}
if (!success) revert TransferOutFailed();
}
/**
* @notice Supply an amount of asset to the protocol
* @param asset The asset to supply
* @param amount The quantity to supply
*/
function supply(address asset, uint amount) override external {
return supplyInternal(msg.sender, msg.sender, msg.sender, asset, amount);
}
/**
* @notice Supply an amount of asset to dst
* @param dst The address which will hold the balance
* @param asset The asset to supply
* @param amount The quantity to supply
*/
function supplyTo(address dst, address asset, uint amount) override external {
return supplyInternal(msg.sender, msg.sender, dst, asset, amount);
}
/**
* @notice Supply an amount of asset from `from` to dst, if allowed
* @param from The supplier address
* @param dst The address which will hold the balance
* @param asset The asset to supply
* @param amount The quantity to supply
*/
function supplyFrom(address from, address dst, address asset, uint amount) override external {
return supplyInternal(msg.sender, from, dst, asset, amount);
}
/**
* @dev Supply either collateral or base asset, depending on the asset, if operator is allowed
* @dev Note: Specifying an `amount` of uint256.max will repay all of `dst`'s accrued base borrow balance
*/
function supplyInternal(address operator, address from, address dst, address asset, uint amount) internal nonReentrant {
if (isSupplyPaused()) revert Paused();
if (!hasPermission(from, operator)) revert Unauthorized();
if (asset == baseToken) {
if (amount == type(uint256).max) {
amount = borrowBalanceOf(dst);
}
return supplyBase(from, dst, amount);
} else {
return supplyCollateral(from, dst, asset, safe128(amount));
}
}
/**
* @dev Supply an amount of base asset from `from` to dst
*/
function supplyBase(address from, address dst, uint256 amount) internal {
amount = doTransferIn(baseToken, from, amount);
accrueInternal();
UserBasic memory dstUser = userBasic[dst];
int104 dstPrincipal = dstUser.principal;
int256 dstBalance = presentValue(dstPrincipal) + signed256(amount);
int104 dstPrincipalNew = principalValue(dstBalance);
(uint104 repayAmount, uint104 supplyAmount) = repayAndSupplyAmount(dstPrincipal, dstPrincipalNew);
totalSupplyBase += supplyAmount;
totalBorrowBase -= repayAmount;
updateBasePrincipal(dst, dstUser, dstPrincipalNew);
emit Supply(from, dst, amount);
if (supplyAmount > 0) {
emit Transfer(address(0), dst, presentValueSupply(baseSupplyIndex, supplyAmount));
}
}
/**
* @dev Supply an amount of collateral asset from `from` to dst
*/
function supplyCollateral(address from, address dst, address asset, uint128 amount) internal {
amount = safe128(doTransferIn(asset, from, amount));
AssetInfo memory assetInfo = getAssetInfoByAddress(asset);
TotalsCollateral memory totals = totalsCollateral[asset];
totals.totalSupplyAsset += amount;
if (totals.totalSupplyAsset > assetInfo.supplyCap) revert SupplyCapExceeded();
uint128 dstCollateral = userCollateral[dst][asset].balance;
uint128 dstCollateralNew = dstCollateral + amount;
totalsCollateral[asset] = totals;
userCollateral[dst][asset].balance = dstCollateralNew;
updateAssetsIn(dst, assetInfo, dstCollateral, dstCollateralNew);
emit SupplyCollateral(from, dst, asset, amount);
}
/**
* @notice ERC20 transfer an amount of base token to dst
* @param dst The recipient address
* @param amount The quantity to transfer
* @return true
*/
function transfer(address dst, uint amount) override external returns (bool) {
transferInternal(msg.sender, msg.sender, dst, baseToken, amount);
return true;
}
/**
* @notice ERC20 transfer an amount of base token from src to dst, if allowed
* @param src The sender address
* @param dst The recipient address
* @param amount The quantity to transfer
* @return true
*/
function transferFrom(address src, address dst, uint amount) override external returns (bool) {
transferInternal(msg.sender, src, dst, baseToken, amount);
return true;
}
/**
* @notice Transfer an amount of asset to dst
* @param dst The recipient address
* @param asset The asset to transfer
* @param amount The quantity to transfer
*/
function transferAsset(address dst, address asset, uint amount) override external {
return transferInternal(msg.sender, msg.sender, dst, asset, amount);
}
/**
* @notice Transfer an amount of asset from src to dst, if allowed
* @param src The sender address
* @param dst The recipient address
* @param asset The asset to transfer
* @param amount The quantity to transfer
*/
function transferAssetFrom(address src, address dst, address asset, uint amount) override external {
return transferInternal(msg.sender, src, dst, asset, amount);
}
/**
* @dev Transfer either collateral or base asset, depending on the asset, if operator is allowed
* @dev Note: Specifying an `amount` of uint256.max will transfer all of `src`'s accrued base balance
*/
function transferInternal(address operator, address src, address dst, address asset, uint amount) internal nonReentrant {
if (isTransferPaused()) revert Paused();
if (!hasPermission(src, operator)) revert Unauthorized();
if (src == dst) revert NoSelfTransfer();
if (asset == baseToken) {
if (amount == type(uint256).max) {
amount = balanceOf(src);
}
return transferBase(src, dst, amount);
} else {
return transferCollateral(src, dst, asset, safe128(amount));
}
}
/**
* @dev Transfer an amount of base asset from src to dst, borrowing if possible/necessary
*/
function transferBase(address src, address dst, uint256 amount) internal {
accrueInternal();
UserBasic memory srcUser = userBasic[src];
UserBasic memory dstUser = userBasic[dst];
int104 srcPrincipal = srcUser.principal;
int104 dstPrincipal = dstUser.principal;