Liquidatable

Liquidatable

The liquidation has a liveness period before expiring successfully, during which someone can "dispute" the liquidation, which sends a price request to the relevant Oracle to settle the final collateralization ratio based on a DVM price. The contract enforces dispute rewards in order to incentivize disputers to correctly dispute false liquidations and compensate position sponsors who had their position incorrectly liquidated. Importantly, a prospective disputer must deposit a dispute bond that they can lose in the case of an unsuccessful dispute. NOTE: this contract does not work with ERC777 collateral currencies or any others that call into the receiver on transfer(). Using an ERC777 token would allow a user to maliciously grief other participants (while also losing money themselves).

Functions

disputable(uint256 liquidationId, address sponsor) modifier

withdrawable(uint256 liquidationId, address sponsor) modifier

onlyPreExpiration() modifier

onlyPostExpiration() modifier

onlyCollateralizedPosition(address sponsor) modifier

onlyOpenState() modifier

noPendingWithdrawal(address sponsor) modifier

fees() modifier

nonReentrant() modifier

Prevents a contract from calling itself, directly or indirectly. Calling a nonReentrant function from another nonReentrant function is not supported. It is possible to prevent this from happening by making the nonReentrant function external, and make it call a private function that does the actual work.

nonReentrantView() modifier

Designed to prevent a view-only method from being re-entered during a call to a nonReentrant() state-changing method.

onlyIfTest() modifier

Reverts if not running in test mode.

constructor(struct Liquidatable.ConstructorParams params) public

Constructs the liquidatable contract.

Parameters:

  • params: struct to define input parameters for construction of Liquidatable. Some params are fed directly into the PricelessPositionManager’s constructor within the inheritance tree.

createLiquidation(address sponsor, struct FixedPoint.Unsigned minCollateralPerToken, struct FixedPoint.Unsigned maxCollateralPerToken, struct FixedPoint.Unsigned maxTokensToLiquidate, uint256 deadline) → uint256 liquidationId, struct FixedPoint.Unsigned tokensLiquidated, struct FixedPoint.Unsigned finalFeeBond external

Liquidates the sponsor’s position if the caller has enough synthetic tokens to retire the position’s outstanding tokens. Liquidations above a minimum size also reset an ongoing "slow withdrawal"'s liveness.

This method generates an ID that will uniquely identify liquidation for the sponsor. This contract must be approved to spend at least tokensLiquidated of tokenCurrency and at least finalFeeBond of collateralCurrency. This contract must have the Burner role for the tokenCurrency.

Parameters:

  • sponsor: address of the sponsor to liquidate.

  • minCollateralPerToken: abort the liquidation if the position’s collateral per token is below this value.

  • maxCollateralPerToken: abort the liquidation if the position’s collateral per token exceeds this value.

  • maxTokensToLiquidate: max number of tokens to liquidate.

  • deadline: abort the liquidation if the transaction is mined after this timestamp.

dispute(uint256 liquidationId, address sponsor) → struct FixedPoint.Unsigned totalPaid external

Disputes a liquidation, if the caller has enough collateral to post a dispute bond and pay a fixed final fee charged on each price request.

Can only dispute a liquidation before the liquidation expires and if there are no other pending disputes. This contract must be approved to spend at least the dispute bond amount of collateralCurrency. This dispute bond amount is calculated from disputeBondPercentage times the collateral in the liquidation.

Parameters:

  • liquidationId: of the disputed liquidation.

  • sponsor: the address of the sponsor whose liquidation is being disputed.

withdrawLiquidation(uint256 liquidationId, address sponsor) → struct Liquidatable.RewardsData public

After a dispute has settled or after a non-disputed liquidation has expired, anyone can call this method to disperse payments to the sponsor, liquidator, and disdputer.

If the dispute SUCCEEDED: the sponsor, liquidator, and disputer are eligible for payment. If the dispute FAILED: only the liquidator can receive payment. This method will revert if rewards have already been dispersed.

Parameters:

  • liquidationId: uniquely identifies the sponsor’s liquidation.

  • sponsor: address of the sponsor associated with the liquidation.

getLiquidations(address sponsor) → struct Liquidatable.LiquidationData[] liquidationData external

Gets all liquidation information for a given sponsor address.

Parameters:

  • sponsor: address of the position sponsor.

transformCollateralRequirement(struct FixedPoint.Unsigned price) → struct FixedPoint.Unsigned public

Accessor method to calculate a transformed collateral requirement using the finanical product library specified during contract deployment. If no library was provided then no modification to the collateral requirement is done.

This method should never revert.

Parameters:

  • price: input price used as an input to transform the collateral requirement.

_settle(uint256 liquidationId, address sponsor) internal

_pfc() → struct FixedPoint.Unsigned internal

_getLiquidationData(address sponsor, uint256 liquidationId) → struct Liquidatable.LiquidationData liquidation internal

_getLiquidationExpiry(struct Liquidatable.LiquidationData liquidation) → uint256 internal

_disputable(uint256 liquidationId, address sponsor) internal

_withdrawable(uint256 liquidationId, address sponsor) internal

_transformCollateralRequirement(struct FixedPoint.Unsigned price) → struct FixedPoint.Unsigned internal

requestTransferPosition() public

Requests to transfer ownership of the caller’s current position to a new sponsor address. Once the request liveness is passed, the sponsor can execute the transfer and specify the new sponsor.

The liveness length is the same as the withdrawal liveness.

transferPositionPassedRequest(address newSponsorAddress) public

After a passed transfer position request (i.e., by a call to requestTransferPosition and waiting withdrawalLiveness), transfers ownership of the caller’s current position to newSponsorAddress.

Transferring positions can only occur if the recipient does not already have a position.

Parameters:

  • newSponsorAddress: is the address to which the position will be transferred.

cancelTransferPosition() external

Cancels a pending transfer position request.

depositTo(address sponsor, struct FixedPoint.Unsigned collateralAmount) public

Transfers collateralAmount of collateralCurrency into the specified sponsor’s position.

Increases the collateralization level of a position after creation. This contract must be approved to spend at least collateralAmount of collateralCurrency.

Parameters:

  • sponsor: the sponsor to credit the deposit to.

  • collateralAmount: total amount of collateral tokens to be sent to the sponsor’s position.

deposit(struct FixedPoint.Unsigned collateralAmount) public

Transfers collateralAmount of collateralCurrency into the caller’s position.

Increases the collateralization level of a position after creation. This contract must be approved to spend at least collateralAmount of collateralCurrency.

Parameters:

  • collateralAmount: total amount of collateral tokens to be sent to the sponsor’s position.

withdraw(struct FixedPoint.Unsigned collateralAmount) → struct FixedPoint.Unsigned amountWithdrawn public

Transfers collateralAmount of collateralCurrency from the sponsor’s position to the sponsor.

Reverts if the withdrawal puts this position’s collateralization ratio below the global collateralization ratio. In that case, use requestWithdrawal. Might not withdraw the full requested amount to account for precision loss.

Parameters:

  • collateralAmount: is the amount of collateral to withdraw.

requestWithdrawal(struct FixedPoint.Unsigned collateralAmount) public

Starts a withdrawal request that, if passed, allows the sponsor to withdraw` from their position.

The request will be pending for withdrawalLiveness, during which the position can be liquidated.

Parameters:

  • collateralAmount: the amount of collateral requested to withdraw

withdrawPassedRequest() → struct FixedPoint.Unsigned amountWithdrawn external

After a passed withdrawal request (i.e., by a call to requestWithdrawal and waiting withdrawalLiveness), withdraws positionData.withdrawalRequestAmount of collateral currency.

Might not withdraw the full requested amount in order to account for precision loss or if the full requested amount exceeds the collateral in the position (due to paying fees).

cancelWithdrawal() external

Cancels a pending withdrawal request.

create(struct FixedPoint.Unsigned collateralAmount, struct FixedPoint.Unsigned numTokens) public

Creates tokens by creating a new position or by augmenting an existing position. Pulls collateralAmount into the sponsor’s position and mints numTokens of tokenCurrency.

Reverts if minting these tokens would put the position’s collateralization ratio below the global collateralization ratio. This contract must be approved to spend at least collateralAmount of collateralCurrency. This contract must have the Minter role for the tokenCurrency.

Parameters:

  • collateralAmount: is the number of collateral tokens to collateralize the position with

  • numTokens: is the number of tokens to mint from the position.

repay(struct FixedPoint.Unsigned numTokens) public

Burns numTokens of tokenCurrency to decrease sponsors position size, without sending back collateralCurrency. This is done by a sponsor to increase position CR. Resulting size is bounded by minSponsorTokens.

Can only be called by token sponsor. This contract must be approved to spend numTokens of tokenCurrency. This contract must have the Burner role for the tokenCurrency.

Parameters:

  • numTokens: is the number of tokens to be burnt from the sponsor’s debt position.

redeem(struct FixedPoint.Unsigned numTokens) → struct FixedPoint.Unsigned amountWithdrawn public

Burns numTokens of tokenCurrency and sends back the proportional amount of collateralCurrency.

Can only be called by a token sponsor. Might not redeem the full proportional amount of collateral in order to account for precision loss. This contract must be approved to spend at least numTokens of tokenCurrency. This contract must have the Burner role for the tokenCurrency.

Parameters:

  • numTokens: is the number of tokens to be burnt for a commensurate amount of collateral.

settleExpired() → struct FixedPoint.Unsigned amountWithdrawn external

After a contract has passed expiry all token holders can redeem their tokens for underlying at the prevailing price defined by the DVM from the expire function.

This burns all tokens from the caller of tokenCurrency and sends back the proportional amount of collateralCurrency. Might not redeem the full proportional amount of collateral in order to account for precision loss. This contract must be approved to spend tokenCurrency at least up to the caller’s full balance. This contract must have the Burner role for the tokenCurrency.

expire() external

Locks contract state in expired and requests oracle price.

this function can only be called once the contract is expired and can’t be re-called.

emergencyShutdown() external

Premature contract settlement under emergency circumstances.

Only the governor can call this function as they are permissioned within the FinancialContractAdmin. Upon emergency shutdown, the contract settlement time is set to the shutdown time. This enables withdrawal to occur via the standard settleExpired function. Contract state is set to ExpiredPriceRequested which prevents re-entry into this function or the expire function. No fees are paid when calling emergencyShutdown as the governor who would call the function would also receive the fees.

remargin() external

Theoretically supposed to pay fees and move money between margin accounts to make sure they reflect the NAV of the contract. However, this functionality doesn’t apply to this contract.

This is supposed to be implemented by any contract that inherits AdministrateeInterface and callable only by the Governor contract. This method is therefore minimally implemented in this contract and does nothing.

getCollateral(address sponsor) → struct FixedPoint.Unsigned external

Accessor method for a sponsor’s collateral.

This is necessary because the struct returned by the positions() method shows rawCollateral, which isn’t a user-readable value. This method accounts for pending regular fees that have not yet been withdrawn from this contract, for example if the lastPaymentTime != currentTime.

Parameters:

  • sponsor: address whose collateral amount is retrieved.

totalPositionCollateral() → struct FixedPoint.Unsigned external

Accessor method for the total collateral stored within the PricelessPositionManager.

This method accounts for pending regular fees that have not yet been withdrawn from this contract, for example if the lastPaymentTime != currentTime.

transformPrice(struct FixedPoint.Unsigned price, uint256 requestTime) → struct FixedPoint.Unsigned public

Accessor method to compute a transformed price using the finanicalProductLibrary specified at contract deployment. If no library was provided then no modification to the price is done.

This method should never revert.

Parameters:

  • price: input price to be transformed.

  • requestTime: timestamp the oraclePrice was requested at.

transformPriceIdentifier(uint256 requestTime) → bytes32 public

Accessor method to compute a transformed price identifier using the finanicalProductLibrary specified at contract deployment. If no library was provided then no modification to the identifier is done.

This method should never revert.

Parameters:

  • requestTime: timestamp the identifier is to be used at.

_reduceSponsorPosition(address sponsor, struct FixedPoint.Unsigned tokensToRemove, struct FixedPoint.Unsigned collateralToRemove, struct FixedPoint.Unsigned withdrawalAmountToRemove) internal

_deleteSponsorPosition(address sponsor) → struct FixedPoint.Unsigned internal

_getPositionData(address sponsor) → struct PricelessPositionManager.PositionData internal

_getIdentifierWhitelist() → contract IdentifierWhitelistInterface internal

_getOracle() → contract OracleInterface internal

_getOptimisticOracle() → contract OptimisticOracleInterface internal

_getFinancialContractsAdminAddress() → address internal

_requestOraclePriceExpiration(uint256 requestedTime) internal

_getOraclePriceExpiration(uint256 requestedTime) → struct FixedPoint.Unsigned internal

_requestOraclePriceLiquidation(uint256 requestedTime) internal

_getOraclePriceLiquidation(uint256 requestedTime) → struct FixedPoint.Unsigned internal

_resetWithdrawalRequest(struct PricelessPositionManager.PositionData positionData) internal

_incrementCollateralBalances(struct PricelessPositionManager.PositionData positionData, struct FixedPoint.Unsigned collateralAmount) → struct FixedPoint.Unsigned internal

_decrementCollateralBalances(struct PricelessPositionManager.PositionData positionData, struct FixedPoint.Unsigned collateralAmount) → struct FixedPoint.Unsigned internal

_decrementCollateralBalancesCheckGCR(struct PricelessPositionManager.PositionData positionData, struct FixedPoint.Unsigned collateralAmount) → struct FixedPoint.Unsigned internal

_onlyOpenState() internal

_onlyPreExpiration() internal

_onlyPostExpiration() internal

_onlyCollateralizedPosition(address sponsor) internal

_positionHasNoPendingWithdrawal(address sponsor) internal

_getSyntheticDecimals(address _collateralAddress) → uint8 decimals public

_transformPrice(struct FixedPoint.Unsigned price, uint256 requestTime) → struct FixedPoint.Unsigned internal

_transformPriceIdentifier(uint256 requestTime) → bytes32 internal

_getAncillaryData() → bytes internal

payRegularFees() → struct FixedPoint.Unsigned public

Pays UMA DVM regular fees (as a % of the collateral pool) to the Store contract.

These must be paid periodically for the life of the contract. If the contract has not paid its regular fee in a week or more then a late penalty is applied which is sent to the caller. If the amount of fees owed are greater than the pfc, then this will pay as much as possible from the available collateral. An event is only fired if the fees charged are greater than 0.

getOutstandingRegularFees(uint256 time) → struct FixedPoint.Unsigned regularFee, struct FixedPoint.Unsigned latePenalty, struct FixedPoint.Unsigned totalPaid public

Fetch any regular fees that the contract has pending but has not yet paid. If the fees to be paid are more than the total collateral within the contract then the totalPaid returned is full contract collateral amount.

This returns 0 and exit early if there is no pfc, fees were already paid during the current block, or the fee rate is 0.

pfc() → struct FixedPoint.Unsigned external

Gets the current profit from corruption for this contract in terms of the collateral currency.

This is equivalent to the collateral pool available from which to pay fees. Therefore, derived contracts are expected to implement this so that pay-fee methods can correctly compute the owed fees as a % of PfC.

gulp() external

Removes excess collateral balance not counted in the PfC by distributing it out pro-rata to all sponsors.

Multiplying the cumulativeFeeMultiplier by the ratio of non-PfC-collateral

PfC-collateral effectively pays all sponsors a pro-rata portion of the excess collateral. This will revert if PfC is 0 and this contract’s collateral balance > 0.

_payFinalFees(address payer, struct FixedPoint.Unsigned amount) internal

_gulp() internal

_getStore() → contract StoreInterface internal

_computeFinalFees() → struct FixedPoint.Unsigned finalFees internal

_getFeeAdjustedCollateral(struct FixedPoint.Unsigned rawCollateral) → struct FixedPoint.Unsigned collateral internal

_getPendingRegularFeeAdjustedCollateral(struct FixedPoint.Unsigned rawCollateral) → struct FixedPoint.Unsigned internal

_convertToRawCollateral(struct FixedPoint.Unsigned collateral) → struct FixedPoint.Unsigned rawCollateral internal

_removeCollateral(struct FixedPoint.Unsigned rawCollateral, struct FixedPoint.Unsigned collateralToRemove) → struct FixedPoint.Unsigned removedCollateral internal

_addCollateral(struct FixedPoint.Unsigned rawCollateral, struct FixedPoint.Unsigned collateralToAdd) → struct FixedPoint.Unsigned addedCollateral internal

_adjustCumulativeFeeMultiplier(struct FixedPoint.Unsigned amount, struct FixedPoint.Unsigned currentPfc) internal

_preEntranceCheck() internal

_preEntranceSet() internal

_postEntranceReset() internal

setCurrentTime(uint256 time) external

Sets the current time.

Will revert if not running in test mode.

Parameters:

  • time: timestamp to set current Testable time to.

getCurrentTime() → uint256 public

Gets the current time. Will return the last time set in setCurrentTime if running in test mode. Otherwise, it will return the block timestamp.

LiquidationCreated(address sponsor, address liquidator, uint256 liquidationId, uint256 tokensOutstanding, uint256 lockedCollateral, uint256 liquidatedCollateral, uint256 liquidationTime) event

LiquidationDisputed(address sponsor, address liquidator, address disputer, uint256 liquidationId, uint256 disputeBondAmount) event

DisputeSettled(address caller, address sponsor, address liquidator, address disputer, uint256 liquidationId, bool disputeSucceeded) event

LiquidationWithdrawn(address caller, uint256 paidToLiquidator, uint256 paidToDisputer, uint256 paidToSponsor, enum Liquidatable.Status liquidationStatus, uint256 settlementPrice) event

RequestTransferPosition(address oldSponsor) event

RequestTransferPositionExecuted(address oldSponsor, address newSponsor) event

RequestTransferPositionCanceled(address oldSponsor) event

Deposit(address sponsor, uint256 collateralAmount) event

Withdrawal(address sponsor, uint256 collateralAmount) event

RequestWithdrawal(address sponsor, uint256 collateralAmount) event

RequestWithdrawalExecuted(address sponsor, uint256 collateralAmount) event

RequestWithdrawalCanceled(address sponsor, uint256 collateralAmount) event

PositionCreated(address sponsor, uint256 collateralAmount, uint256 tokenAmount) event

NewSponsor(address sponsor) event

EndedSponsorPosition(address sponsor) event

Repay(address sponsor, uint256 numTokensRepaid, uint256 newTokenCount) event

Redeem(address sponsor, uint256 collateralAmount, uint256 tokenAmount) event

ContractExpired(address caller) event

SettleExpiredPosition(address caller, uint256 collateralReturned, uint256 tokensBurned) event

EmergencyShutdown(address caller, uint256 originalExpirationTimestamp, uint256 shutdownTimestamp) event

RegularFeesPaid(uint256 regularFee, uint256 lateFee) event

FinalFeesPaid(uint256 amount) event

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