> For the complete Linea documentation index, see [llms.txt](/llms.txt). > Agents can fetch this page as Markdown at [https://docs.linea.build/api/linea-smart-contracts/interfaces/l2/il2messagemanager.md](https://docs.linea.build/api/linea-smart-contracts/interfaces/l2/il2messagemanager.md). # IL2MessageManager # `IL2MessageManager` ### RollingHashUpdated ```solidity event RollingHashUpdated(uint256 messageNumber, bytes32 rollingHash) ``` Emitted after all messages are anchored on L2 and the latest message index and rolling hash stored. _NB: This event is used to provide data to the rollup. The last messageNumber and rollingHash, emitted in a rollup will be used in the public input for validating the L1->L2 messaging state transition._ #### Parameters | Name | Type | Description | | --- | --- | --- | | messageNumber | uint256 | The indexed unique L1 computed indexed message number for the message. | | rollingHash | bytes32 | The indexed L1 rolling hash computed for the current message number. | ### ServiceVersionMigrated ```solidity event ServiceVersionMigrated(uint256 version) ``` _Emitted when the service switches over to a new version. This is currently not in use, but left for existing consumers._ #### Parameters | Name | Type | Description | | --- | --- | --- | | version | uint256 | The indexed version. | ### MessageHashesListLengthIsZero ```solidity error MessageHashesListLengthIsZero() ``` _Reverts when the message hashes array length is zero._ ### L1MessageNumberSynchronizationWrong ```solidity error L1MessageNumberSynchronizationWrong(uint256 expected, uint256 found) ``` _Reverts when message number synchronization is mismatched._ ### L1RollingHashSynchronizationWrong ```solidity error L1RollingHashSynchronizationWrong(bytes32 expected, bytes32 found) ``` _Reverts when rolling hash synchronization is mismatched._ ### FinalRollingHashIsZero ```solidity error FinalRollingHashIsZero() ``` _Reverts when final rolling hash is zero hash._ ### anchorL1L2MessageHashes ```solidity function anchorL1L2MessageHashes(bytes32[] _messageHashes, uint256 _startingMessageNumber, uint256 _finalMessageNumber, bytes32 _finalRollingHash) external ``` Add cross-chain L1->L2 message hashes in storage. _Only address that has the role 'L1_L2_MESSAGE_SETTER_ROLE' are allowed to call this function. NB: In the unlikely event of a duplicate anchoring, the lastAnchoredL1MessageNumber MUST NOT be incremented. and the rolling hash not calculated, else synchronisation will break. If starting number is zero, an underflow error is expected._ #### Parameters | Name | Type | Description | | --- | --- | --- | | _messageHashes | bytes32[] | New message hashes to anchor on L2. | | _startingMessageNumber | uint256 | The expected L1 message number to start when anchoring. | | _finalMessageNumber | uint256 | The expected L1 message number to end on when anchoring. | | _finalRollingHash | bytes32 | The expected L1 rolling hash to end on when anchoring. | Contributions not accepted These reference pages are automatically generated based on Linea's [smart contracts](https://github.com/Consensys/linea-monorepo/tree/main/contracts/src). To ensure they accurately match the deployed smart contracts, we cannot accept any contributions that edit these pages.