The BancorX contract allows cross chain token transfers.

There are two processes that take place in the contract -

• Initiate a cross chain transfer to a target blockchain (locks tokens from the caller account on Ethereum)

• Report a cross chain transfer initiated on a source blockchain (releases tokens to an account on Ethereum)

Reporting cross chain transfers works similar to standard multisig contracts, meaning that multiple

callers are required to report a transfer before tokens are released to the target account.

Functions:

• ​constructor(uint256 _maxLockLimit, uint256 _maxReleaseLimit, uint256 _minLimit, uint256 _limitIncPerBlock, uint8 _minRequiredReports, contract IContractRegistry _registry, contract IERC20Token _token)​

• ​setMaxLockLimit(uint256 _maxLockLimit)​

• ​setMaxReleaseLimit(uint256 _maxReleaseLimit)​

• ​setMinLimit(uint256 _minLimit)​

• ​setLimitIncPerBlock(uint256 _limitIncPerBlock)​

• ​setMinRequiredReports(uint8 _minRequiredReports)​

• ​setReporter(address _reporter, bool _active)​

• ​enableXTransfers(bool _enable)​

• ​enableReporting(bool _enable)​

• ​upgrade(address[] _reporters)​

• ​xTransfer(bytes32 _toBlockchain, bytes32 _to, uint256 _amount)​

• ​xTransfer(bytes32 _toBlockchain, bytes32 _to, uint256 _amount, uint256 _id)​

• ​reportTx(bytes32 _fromBlockchain, uint256 _txId, address _to, uint256 _amount, uint256 _xTransferId)​

• ​getXTransferAmount(uint256 _xTransferId, address _for)​

• ​getCurrentLockLimit()​

• ​getCurrentReleaseLimit()​

Events:

• ​TokensLock(address _from, uint256 _amount)​

• ​TokensRelease(address _to, uint256 _amount)​

• ​XTransfer(address _from, bytes32 _toBlockchain, bytes32 _to, uint256 _amount, uint256 _id)​

• ​TxReport(address _reporter, bytes32 _fromBlockchain, uint256 _txId, address _to, uint256 _amount, uint256 _xTransferId)​

• ​XTransferComplete(address _to, uint256 _id)​

Function constructor(uint256 _maxLockLimit, uint256 _maxReleaseLimit, uint256 _minLimit, uint256 _limitIncPerBlock, uint8 _minRequiredReports, contract IContractRegistry _registry, contract IERC20Token _token)

initializes a new BancorX instance

Parameters:

• _maxLockLimit: maximum amount of tokens that can be locked in one transaction

• _maxReleaseLimit: maximum amount of tokens that can be released in one transaction

• _minLimit: minimum amount of tokens that can be transferred in one transaction

• _limitIncPerBlock: how much the limit increases per block

• _minRequiredReports: minimum number of reporters to report transaction before tokens can be released

• _registry: address of contract registry

• _token: erc20 token

Function setMaxLockLimit(uint256 _maxLockLimit)

setter

Parameters:

• _maxLockLimit: new maxLockLimit

Function setMaxReleaseLimit(uint256 _maxReleaseLimit)

setter

Parameters:

• _maxReleaseLimit: new maxReleaseLimit

Function setMinLimit(uint256 _minLimit)

setter

Parameters:

• _minLimit: new minLimit

Function setLimitIncPerBlock(uint256 _limitIncPerBlock)

setter

Parameters:

• _limitIncPerBlock: new limitIncPerBlock

Function setMinRequiredReports(uint8 _minRequiredReports)

setter

Parameters:

• _minRequiredReports: new minRequiredReports

Function setReporter(address _reporter, bool _active)

allows the owner to set/remove reporters

Parameters:

• _reporter: reporter whos status is to be set

• _active: true if the reporter is approved, false otherwise

Function enableXTransfers(bool _enable)

allows the owner enable/disable the xTransfer method

Parameters:

• _enable: true to enable, false to disable

Function enableReporting(bool _enable)

allows the owner enable/disable the reportTransaction method

Parameters:

• _enable: true to enable, false to disable

Function upgrade(address[] _reporters)

upgrades the contract to the latest version

can only be called by the owner

note that the owner needs to call acceptOwnership on the new contract after the upgrade

Parameters:

• _reporters: new list of reporters

Function xTransfer(bytes32 _toBlockchain, bytes32 _to, uint256 _amount)

claims tokens from msg.sender to be converted to tokens on another blockchain

Parameters:

• _toBlockchain: blockchain on which tokens will be issued

• _to: address to send the tokens to

• _amount: the amount of tokens to transfer

Function xTransfer(bytes32 _toBlockchain, bytes32 _to, uint256 _amount, uint256 _id)

claims tokens from msg.sender to be converted to tokens on another blockchain

Parameters:

• _toBlockchain: blockchain on which tokens will be issued

• _to: address to send the tokens to

• _amount: the amount of tokens to transfer

• _id: pre-determined unique (if non zero) id which refers to this transaction

Function reportTx(bytes32 _fromBlockchain, uint256 _txId, address _to, uint256 _amount, uint256 _xTransferId)

allows reporter to report transaction which occured on another blockchain

Parameters:

• _fromBlockchain: blockchain in which tokens were destroyed

• _txId: transactionId of transaction thats being reported

• _to: address to receive tokens

• _amount: amount of tokens destroyed on another blockchain

• _xTransferId: unique (if non zero) pre-determined id (unlike _txId which is determined after the transactions been mined)

Function getXTransferAmount(uint256 _xTransferId, address _for) → uint256

gets x transfer amount by xTransferId (not txId)

Parameters:

• _xTransferId: unique (if non zero) pre-determined id (unlike _txId which is determined after the transactions been broadcasted)

• _for: address corresponding to xTransferId

Return Values:

• amount that was sent in xTransfer corresponding to _xTransferId

Function getCurrentLockLimit() → uint256

method for calculating current lock limit

Return Values:

• the current maximum limit of tokens that can be locked

Function getCurrentReleaseLimit() → uint256

method for calculating current release limit

Return Values:

• the current maximum limit of tokens that can be released

Event TokensLock(address _from, uint256 _amount)

triggered when tokens are locked in smart contract

Parameters:

• _from: wallet address that the tokens are locked from

• _amount: amount locked

Event TokensRelease(address _to, uint256 _amount)

triggered when tokens are released by the smart contract

Parameters:

• _to: wallet address that the tokens are released to

• _amount: amount released

Event XTransfer(address _from, bytes32 _toBlockchain, bytes32 _to, uint256 _amount, uint256 _id)

triggered when xTransfer is successfully called

Parameters:

• _from: wallet address that initiated the xtransfer

• _toBlockchain: target blockchain

• _to: target wallet

• _amount: transfer amount

• _id: xtransfer id

Event TxReport(address _reporter, bytes32 _fromBlockchain, uint256 _txId, address _to, uint256 _amount, uint256 _xTransferId)

triggered when report is successfully submitted

Parameters:

• _reporter: reporter wallet

• _fromBlockchain: source blockchain

• _txId: tx id on the source blockchain

• _to: target wallet

• _amount: transfer amount

• _xTransferId: xtransfer id

Event XTransferComplete(address _to, uint256 _id)

triggered when final report is successfully submitted

Parameters:

• _to: target wallet

• _id: xtransfer id