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.

Functions

disputable(uint256 liquidationId, address sponsor) modifier

MODIFIERS

==== withdrawable(uint256 liquidationId, address sponsor) modifier

==== onlyPreExpiration() modifier

MODIFIERS

onlyPostExpiration() modifier

onlyCollateralizedPosition(address sponsor) modifier

onlyOpenState() modifier

noPendingWithdrawal(address sponsor) modifier

fees() modifier

MODIFIERS

==== 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.

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.

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 disputeBondPct 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 FixedPoint.Unsigned amountWithdrawn public

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

If the dispute SUCCEEDED: the sponsor, liquidator, and disputer are eligible for payment. If the dispute FAILED: only the liquidator can receive payment. Once all collateral is withdrawn, delete the liquidation data.

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.

==== _settle(uint256 liquidationId, address sponsor) internal

INTERNAL FUNCTIONS

_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

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.

Parameters:

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

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

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.

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 collateralAmount 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.

Parameters:

  • sponsor: address whose collateral amount is retrieved.

totalPositionCollateral() → struct FixedPoint.Unsigned totalCollateral external

Accessor method for the total collateral stored within the PricelessPositionManager.

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

INTERNAL FUNCTIONS

==== _deleteSponsorPosition(address sponsor) → struct FixedPoint.Unsigned internal

==== _getPositionData(address sponsor) → struct PricelessPositionManager.PositionData internal

==== _getIdentifierWhitelist() → contract IdentifierWhitelistInterface internal

==== _getOracle() → contract OracleInterface internal

==== _getFinancialContractsAdminAddress() → address internal

==== _requestOraclePrice(uint256 requestedTime) internal

==== _getOraclePrice(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

==== payRegularFees() → struct FixedPoint.Unsigned totalPaid 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.

==== pfc() → struct FixedPoint.Unsigned public

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.

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

INTERNAL FUNCTIONS

_getStore() → contract StoreInterface internal

_computeFinalFees() → struct FixedPoint.Unsigned finalFees internal

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

EVENTS

==== 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 withdrawalAmount, enum Liquidatable.Status liquidationStatus) event

==== RequestTransferPosition(address oldSponsor) event

EVENTS

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

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

EVENTS

==== FinalFeesPaid(uint256 amount) event

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