CrosschainLib

CrosschainLib

Provides utilities for validating bridgeable token pairs, handling BSC decimal conversions, and resolving Across handler addresses.

Used by cross-chain adapters to ensure token compatibility and proper decimal handling.

UnsupportedCrossChainToken

error UnsupportedCrossChainToken()

WrongDestinationToken

error WrongDestinationToken()

DEFAULT_MULTICALL_HANDLER

address DEFAULT_MULTICALL_HANDLER

Across MulticallHandler addresses

BSC_MULTICALL_HANDLER

address BSC_MULTICALL_HANDLER

isAllowedCrosschainToken

function isAllowedCrosschainToken(address token) internal view returns (bool)

Check if a token is allowed for cross-chain operations on the current chain.

Parameters

Name	Type	Description
token	address	The token address to check.

Return Values

Name	Type	Description
[0]	bool	True if the token is allowed for cross-chain operations.

applyBscDecimalConversion

function applyBscDecimalConversion(address inputToken, address outputToken, uint256 amount) internal pure returns (uint256)

Applies BSC decimal conversion for USDC/USDT (18 decimals on BSC vs 6 on other chains).

Handles bidirectional conversion to ensure exact cross-chain value calculation.

Parameters

Name	Type	Description
inputToken	address	Source token address.
outputToken	address	Destination token address.
amount	uint256	Original amount in source chain decimals.

Return Values

Name	Type	Description
[0]	uint256	Normalized amount for correct cross-chain virtual supply calculation.

getAcrossHandler

function getAcrossHandler(uint256 chainId) internal pure returns (address handler)

Get the appropriate Across MulticallHandler address for a given chain.

BSC (chain ID 56) uses a different handler than other chains.

Parameters

Name	Type	Description
chainId	uint256	The destination chain ID.

Return Values

Name	Type	Description
handler	address	The MulticallHandler address for the specified chain.

validateBridgeableTokenPair

function validateBridgeableTokenPair(address inputToken, address outputToken) internal pure

Validates that input and output tokens are compatible for cross-chain bridging.

Only allows bridging between tokens of the same type (USDC↔USDC, USDT↔USDT, etc.).

Parameters

Name	Type	Description
inputToken	address	Source token address.
outputToken	address	Destination token address.