CMPVault

Initialization

constructor

constructor(IERC20 asset_, bytes memory data)

Description

The constructor initializes the CMPVault contract, setting up the initial parameters required.

Parameters

• asset_: Instance of the ERC20 token (Tether Gold - XAUT) used as collateral to mint aUSDT.

• data: Encoded data containing essential parameters required for the contract initialization.

Functionality

1. Asset Initialization: Sets the asset variable to the specified ERC20 token instance.

2. Decoding Parameters: Decodes the input data to extract the following parameters:

   • collateral: Instance of the collateral token (Tether Gold - XAUT) used.

   • oracle: Oracle contract address.

   • LIQUIDATION_MULTIPLIER: Multiplier used in determining the liquidation threshold.

   • COLLATERALIZATION_RATE: Rate at which collateralization must be maintained.

   • MINT_OPENING_RETURN_FEE: Fee charged for mint and return.

Usage

The constructor is called during the deployment of the CMPVault contract. It initializes the necessary parameters for the functioning of the contract and disables further initializers by calling _disableInitializers().

initialize

function initialize(bytes memory oracleData_, uint64 interest) public initializer

Description

The initialize function further initializes the contract after deployment, setting additional parameters and executing specific actions required for functionality.

Parameters

• oracleData_: Empty memory bytes.

• interest: The chosen interest rate.

Functionality

1. Ownership Initialization: Initializes ownership through the __Ownable_init() function.

2. Interest: Updates the accrueInfo.interest variable.

3. Mint Limit Setup: Sets the mintLimit to the maximum allowed value.

4. Blacklist Callees: Adds the contract's own address, collateral token address, and asset token address to the blacklistedCallees to prevent recursive calls.

5. Fetching Exchange Rate: Retrieves the current exchange rate from the Oracle contract.

6. Accrue Function Call: Executes the accrue() function to initialize certain internal values.

Usage

This function is called after the contract deployment to set up additional parameters and perform initial actions required for the contract's functionality.

Write Methods

accrue

function accrue() public

Description

This function is responsible for calculating and accruing interest on outstanding mintings.

Emits

LogAccrue

updateExchangeRate

function updateExchangeRate() public 
    returns (bool updated, uint256 rate)

Description

Updates the exchange rate (see oracle).

Returns

Name	Type	Description
updated	bool	A boolean indicating whether the exchange rate update was successful.
rate	uint256	The latest exchange rate fetched from the oracle smart contract.

Emits

LogExchangeRate

addCollateral

function addCollateral(address to, uint256 share)
    public virtual onlyWhitelisted(to)

Description

Adds a share amount of collateral token to to.

Your smart contract must approveaddress(this) to transfer the shares:

collateral.approve(address(CMPVault), share);

Parameters

Name	Type	Description
to	address	The receiver of the collateral tokens.
share	uint256	The amount of tokens to add.

Emits

LogAddCollateral

removeCollateral

function removeCollateral(address to, uint256 share)
    public onlyWhitelisted(msg.sender) solvent

Description

Removes a share amount of collateral token from msg.sender.

Parameters

Name	Type	Description
to	address	The receiver of the collateral tokens.
share	uint256	The amount of tokens to remove.

Emits

LogRemoveCollateral

mint

function mint(address to, uint256 amount)
    public solvent onlyWhitelisted(msg.sender)
    returns (uint256 part, uint256 share)

Description

Mints an amount of asset tokens.

Parameters

Name	Type	Description
to	address	The receiver of the asset tokens.
amount	uint256	The amount of asset tokens to mint.

Returns

Name	Type	Description
part	uint256	The mint part held by the user.
share	uint256	Warning: this value is always set to 0.

Emits

LogAccrue

LogMint

returning

function returning(address to, uint256 part)
    public returns (uint256 amount)

Description

Returns a loan.

Parameters

Name	Type	Description
to	address	The address for which to return the loan.
part	uint256	The amount to return (see userMintPart).

Returns

Name	Type	Description
amount	uint256	The amount of asset tokens that has been returned.

Emits

LogAccrue

LogReturn

manage

function manage(
    uint8[] calldata actions,
    uint256[] calldata values,
    bytes[] calldata datas
) external payable virtual onlyWhitelisted(msg.sender)
    returns (uint256 value1, uint256 value2)

Description

Executes a set of actions and allows composability (contract calls) to other contracts.

The manage function allows to bundle functionality within one contract call while passing return values from one call to the next one.

Actions are defined by a numeric identifier and can return two values, value1 and value2 to the next function. The input arrays actions, values and datas define the sequential actions. In the values array the ether value of a call may be defined.

Whereas calling functions like mint that have the solvent modifier requires solvency at the end of the function, solvency only needs to be guaranteed at the end of the manage function, thereby allowing more complicated operations such as leveraging within one call.

For certain parameters either an external value can be passed in or the identifier USEVALUE1 (-1) or USE_VALUE2 (-2) to access either of the local variables. The following variables are marked in bold italic in the table below. If an action returns one value it is saved as value1, if two are returned they are saved as value1 and value2 respectively. Any action can access these values during the whole duration of the manage call.

The call data for the actions is ABI encoded as listed below.

Action	ID	Parameters	ABI encoding	value1	value2
Update exchange rate	11	must_update, minRate, maxRate	bool, uint256, uint256	-	-
Add collateral	10	share, to	int256, address	-	-
Remove collateral	4	share, to	int256, address	-	-
Mint	5	amount, to	int256, address	part	share
Return	2	part, to	int256, address	-	-
Get return amount	6	part	int256	amount	-
Get return part	7	amount	int256	part	-
Liquidate	31	users, maxMintParts, to, swapper, swapperData	address[], uint256[], address, ISwapperV2, bytes	-	-
Call	30	callee, callData, useValue1, useValue2, returnValues	address, bytes, bool, bool, uint8	Depends on the contract call.	Depends on the contract call.

Parameters

Name	Type	Description
actions	uint8[]	An array containing the sequence of actions to execute (IDs)
values	uint256[]	The ETH amount to send along with each action (one-to-one mapping).
data	bytes[]	The ABI encoding containing the function arguments for each action (one-to-one mapping).

Returns

Name	Type	Description
value1	uint256	The first return value (may be unset depending on the last action).
value2	uint256	The second return value (may be unset depending on the last action).

liquidate

function liquidate(
    address[] memory users,
    uint256[] memory maxMintParts,
    address to,
    ISwapperV2 swapper,
    bytes memory swapperData
) public virtual onlyLiquidators(msg.sender)

Description

Handles the liquidation of users' balances, once the users' amount of collateral is too low.

Parameters

Name	Type	Description
users	address[]	An array of user addresses.
maxMintParts	uint256[]	A one-to-one mapping to users, contains maximum (partial) mint amounts (to liquidate) of the respective user.
to	address	Address of the receiver in open liquidations if swapper is zero.
swapper	ISwapperV2	Contract address of the ISwapper implementation, swappers are restricted for closed liquidations
swapperData	bytes	The ABI encoding to pass to the swap function data argument.

Emits

LogRemoveCollateral

LogReturn

LogLiquidation

withdrawFees

function withdrawFees() public

Description

Transfers all available fees to feeTo.

Emits

LogAccrue

LogWithdrawFees

setFeeTo

function setFeeTo(address newFeeTo) public onlyOwner

Description

Allows owner to change the recipient of the fees.

Parameters

Name	Type	Description
newFeeTo	address	The new recipient (see feeTo).

Emits

LogFeeTo

reduceSupply

function reduceSupply(uint256 amount) public onlyOwner

Description

Reduce the available supply of asset tokens.

Parameters

Name	Type	Description
amount	uint256	The amount of asset tokens to remove from the contract's supply.

changeInterestRate

function changeInterestRate(uint64 newInterestRate) public onlyOwner

Description

Allows owner to change the interest rate.

Parameters

Name	Type	Description
newInterestRate	uint64	The new interest rate.

Emits

LogInterestChange

changeMintLimit

function changeMintLimit(uint128 newMintLimit, uint128 perAddressPart) public onlyOwner

Description

Allows owner to change the mint limit.

Parameters

Name	Type	Description
newMintLimit	uint128	The mint limit.
perAddressPart	uint128	The mint limit per user address.

Emits

LogChangeMintLimit

changePermissionControl

function changePermissionControl(PermissionControl newPermissionControl) public onlyOwner

Description

Allows owner to change the permission control contract.

Parameters

Name	Type	Description
newPermissionControl	PermissionControl	The new permission control contract (see permissionControl).

Emits

LogChangePermissionControl

setBlacklistedCallee

function setBlacklistedCallee(address callee, bool blacklisted) public onlyOwner

Description

Allows owner to:

• add a callee to the blacklist.

• remove a callee from the blacklist.

Parameters

Name	Type	Description
callee	address	The callee's address.
blacklisted	bool	The status to set to callee.

Emits

LogChangeBlacklistedCallee

View Methods

asset

IERC20 public immutable asset;

Description

The ERC20 token the users can mint.

collateral

IERC20 public immutable collateral;

Description

The ERC20 token that acts as collateral to mint asset tokens.

userMintPart

mapping(address => uint256) public userMintPart;

Description

Maps each user to its total debt (i.e. its mint part).

You can convert this number into a numerical amount of asset tokens with:

totalMint.elastic / totalMint.base * userMintPart[user]

userCollateralAmount

mapping(address => uint256) public userCollateralAmount;

Description

Maps each user to its amount of collateral tokens.

totalMint

Rebase public totalMint;

Description

Represents the total loan held by minters.

Properties

Name	Type	Description
elastic	uint128	The total amount of asset tokens held by minters.
base	uint128	The total amount of mint parts held by minters.

totalCollateralAmount

uint256 public totalCollateralAmount;

Description

The total amount of collateral tokens.

feeTo

address public feeTo;

Description

The recipient that will receive the fees.

oracle

IOracle public immutable oracle;

Description

The oracle from which to fetch the exchange rate.

oracleData

bytes public oracleData;

Description

The ABI encoding to pass to the oracle get function.

blacklistedCallees

mapping(address => bool) public blacklistedCallees;

Description

If an address maps to true all manageCall actions to its functions are forbidden.

accrueInfo

AccrueInfo public accrueInfo;

Description

Some data about the accrue function.

Properties

Name	Type	Description
lastAccrued	uint64	The timestamp of the last accrue call.
feesEarned	uint128	The fees earned between the last withdrawal and the last accrue call.
interest	uint64	The accrued interest.

permissionControl

PermissionControl public permissionControl;

Description

See PermissionControl.

mintLimit

MintCap public mintLimit;

Description

The current mint limit (in mint parts).

Properties

Name	Type	Description
total	uint128	The mint limit on the total amount of asset tokens in the contract's balance.
mintPartPerAddress	uint128	The mint limit per user address.

COLLATERALIZATION_RATE

uint256 public immutable COLLATERALIZATION_RATE;

Description

The collateralization rate (i.e. maximum % mintable with current collateral).

LIQUIDATION_MULTIPLIER

uint256 public immutable LIQUIDATION_MULTIPLIER;

Description

The liquidation multiplier.

MINT_OPENING_RETURN_FEE

uint256 public immutable MINT_OPENING_RETURN_FEE;

Description

The mint/return fee.

Modifiers

onlyWhitelisted

modifier onlyWhitelisted(address user)

Description

Checks if user is present in the whitelist.

Parameters

Name	Type	Description
user	address	The address to check.

onlyLiquidators

modifier onlyLiquidators(address liquidator)

Description

Checks if liquidator is a liquidator.

Parameters

Name	Type	Description
liquidator	address	The address to check.

solvent

modifier solvent()

Description

Checks if msg.sender is solvent after executing the function body.

Events

LogAccrue

event LogAccrue(uint128 accruedAmount)

Parameters

Name	Type	Index?
accruedAmount	uint256	No

LogExchangeRate

event LogExchangeRate(uint256 rate);

Parameters

Name	Type	Index?
rate	uint256	No

LogAddCollateral

event LogAddCollateral(
    address indexed from,
    address indexed to,
    uint256 share
)

Parameters

Name	Type	Index?
from	address	Yes
to	address	Yes
share	uint256	No

LogRemoveCollateral

event LogRemoveCollateral(
    address indexed from,
    address indexed to,
    uint256 share
)

Parameters

Name	Type	Index?
from	address	Yes
to	address	Yes
share	uint256	No

LogMint

event LogMint(
    address indexed from,
    address indexed to,
    uint256 amount,
    uint256 part
)

Parameters

Name	Type	Index?
from	address	Yes
to	address	Yes
amount	uint256	No
part	uint256	No

LogReturn

event LogReturn(
    address indexed from,
    address indexed to,
    uint256 amount,
    uint256 part
);

Parameters

Name	Type	Index?
from	address	Yes
to	address	Yes
amount	uint256	No
part	uint256	No

LogLiquidation

event LogLiquidation(
    address indexed from,
    address indexed user,
    address indexed to,
    uint256 collateralAmount,
    uint256 mintAmount,
    uint256 mintPart
);

Parameters

Name	Type	Index?
from	address	Yes
user	address	Yes
to	address	Yes
collateralAmount	uint256	No
mintAmount	uint256	No
mintPart	uint256	No

LogWithdrawFees

event LogWithdrawFees(
    address indexed feeTo,
    uint256 feesEarnedFraction
);

Parameters

Name	Type	Index?
feeTo	address	Yes
feesEarnedFraction	uint256	No

LogFeeTo

event LogFeeTo(address indexed newFeeTo);

Parameters

Name	Type	Index?
newFeeTo	address	Yes

LogInterestChange

event LogInterestChange(
    uint64 oldInterestRate,
    uint64 newInterestRate
);

Parameters

Name	Type	Index?
oldInterestRate	uint64	No
newInterestRate	uint64	No

LogChangeMintLimit

event LogChangeMintLimit(
    uint128 newLimit,
    uint128 perAddressPart
);

Parameters

Name	Type	Index?
newLimit	uint128	No
perAddressPart	uint128	No

LogChangeBlacklistedCallee

event LogChangeBlacklistedCallee(
    address indexed account,
    bool blacklisted
);

Parameters

Name	Type	Index?
account	address	Yes
blacklisted	bool	No

LogChangePermissionControl

event LogChangePermissionControl(PermissionControl indexed newPermissionControl);

Parameters

Name	Type	Index?
newPermissionControl	PermissionControl	Yes