L1Withdrawer

Table of Contents

• Summary
• Functions
  • receive
  • setMinWithdrawalAmount
  • setRecipient
  • setWithdrawalGasLimit
• Events
  • WithdrawalInitiated
  • MinWithdrawalAmountUpdated
  • RecipientUpdated
  • WithdrawalGasLimitUpdated
  • FundsReceived

Summary

An optional periphery contract designed to be used as a recipient for a portion of the shares sent by the FeeSplitter. Its sole purpose is to initiate a withdrawal to L1 via L2CrossDomainMessenger.sendMessage() once it has received enough funds. Using the CrossDomainMessenger allows failed withdrawal messages to be replayed, providing better reliability than direct message passing.

Functions

receive

Initiates the withdrawal process to L1 if and only if the contract holds funds equal to or above the minWithdrawalAmount threshold.

receive() external payable

• MUST initiate a withdrawal to the set recipient if and only if the minWithdrawalAmount threshold is reached, using L2CrossDomainMessenger.sendMessage() with the following parameters:
  • _target: the configured recipient address
  • _message: empty bytes (hex"") for direct ETH transfer
  • _minGasLimit: the configured withdrawalGasLimit value
  • msg.value: the contract's entire balance
• MUST emit the FundsReceived event with the sender, amount received and balance.
• MUST emit the WithdrawalInitiated event only if the threshold is reached.

setMinWithdrawalAmount

Updates the minimum withdrawal amount the contract must hold before the withdrawal process can be initiated.

function setMinWithdrawalAmount(uint256 _newMinWithdrawalAmount) external

• MUST only be callable by ProxyAdmin.owner().
• MUST emit the MinWithdrawalAmountUpdated event.
• MUST update the minWithdrawalAmount storage variable.

setRecipient

Updates the address that will receive the funds on L1 during the withdrawal process.

function setRecipient(address _newRecipient) external

• MUST only be callable by ProxyAdmin.owner().
• MUST emit the RecipientUpdated event.
• MUST update the recipient storage variable.

setWithdrawalGasLimit

Updates the gas limit for the withdrawal on L1.

function setWithdrawalGasLimit(uint32 _newWithdrawalGasLimit) external

• MUST only be callable by ProxyAdmin.owner().
• MUST emit the WithdrawalGasLimitUpdated event.
• MUST update the withdrawalGasLimit storage variable.

Events

WithdrawalInitiated

Emitted when a withdrawal to L1 is initiated.

event WithdrawalInitiated(address indexed recipient, uint256 amount)

MinWithdrawalAmountUpdated

Emitted when the minimum withdrawal amount before the withdrawal can be initiated is updated.

event MinWithdrawalAmountUpdated(uint256 oldMinWithdrawalAmount, uint256 newMinWithdrawalAmount)

RecipientUpdated

Emitted when the recipient of the funds on L1 is updated.

event RecipientUpdated(address oldRecipient, address newRecipient)

WithdrawalGasLimitUpdated

Emitted when the withdrawal gas limit on L1 is updated.

event WithdrawalGasLimitUpdated(uint32 oldWithdrawalGasLimit, uint32 newWithdrawalGasLimit)

FundsReceived

Emitted whenever funds are received.

event FundsReceived(address indexed sender, uint256 amount, uint256 newBalance)