DonationVault

DonationVault

Vault that allows making BTC donations to the system. Upon deposit, this vault does not increase depositors' balances and always decreases its own balance in the same transaction. The vault also allows making donations using existing Bank balances.

BEWARE: ALL BTC DEPOSITS TARGETING THIS VAULT ARE NOT REDEEMABLE AND THERE IS NO WAY TO RESTORE THE DONATED BALANCE. USE THIS VAULT ONLY WHEN YOU REALLY KNOW WHAT YOU ARE DOING!

bank

contract Bank bank

DonationReceived

event DonationReceived(address donor, uint256 donatedAmount)

onlyBank

modifier onlyBank()

constructor

constructor(contract Bank _bank) public

donate

function donate(uint256 amount) external

Transfers the given amount of the Bank balance from the caller to the Donation Vault and immediately decreases the vault's balance in the Bank by the transferred amount.

Requirements:

• The caller's balance in the Bank must be greater than or equal to the amount,

• Donation Vault must have an allowance for caller's balance in the Bank for at least amount.

Parameters

Name	Type	Description
amount	uint256	Amount of the Bank balance to donate.

receiveBalanceApproval

function receiveBalanceApproval(address owner, uint256 amount, bytes) external

Transfers the given amount of the Bank balance from the owner to the Donation Vault and immediately decreases the vault's balance in the Bank by the transferred amount.

Requirements:

• Can only be called by the Bank via approveBalanceAndCall,

• The owner balance in the Bank must be greater than or equal to the amount.

Parameters

Name	Type	Description
owner	address	Address of the Bank balance owner who approved their balance to be used by the vault.
amount	uint256	The amount of the Bank balance approved by the owner to be used by the vault.
	bytes

receiveBalanceIncrease

function receiveBalanceIncrease(address[] depositors, uint256[] depositedAmounts) external

Ignores the deposited amounts and does not increase depositors' individual balances. The vault decreases its own tBTC balance in the Bank by the total deposited amount.

Requirements:

• Can only be called by the Bank after the Bridge swept deposits and Bank increased balance for the vault,

• The depositors array must not be empty,

• The depositors array length must be equal to the depositedAmounts array length.

Parameters

Name	Type	Description
depositors	address[]	Addresses of depositors whose deposits have been swept.
depositedAmounts	uint256[]	Amounts deposited by individual depositors and swept.