tornado-nova/contracts/libraries/Bytes.sol
2022-01-22 03:23:33 +03:00

36 lines
1.3 KiB
Solidity

// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;
/**
* @title Bytes
* @dev Helper methods to transform bytes to other solidity types.
*/
library BytesHelper {
/**
* @dev Truncate bytes array if its size is more than 20 bytes.
* NOTE: This function does not perform any checks on the received parameter.
* Make sure that the _bytes argument has a correct length, not less than 20 bytes.
* A case when _bytes has length less than 20 will lead to the undefined behaviour,
* since assembly will read data from memory that is not related to the _bytes argument.
* @param _bytes to be converted to address type
* @return addr address included in the firsts 20 bytes of the bytes array in parameter.
*/
function bytesToAddress(bytes memory _bytes) internal pure returns (address addr) {
assembly {
addr := mload(add(_bytes, 20))
}
}
/**
* @param _bytes it's 32 length slice to be converted to uint type
* @param _start start index of slice
* @return x uint included in the 32 length slice of the bytes array in parameter.
*/
function sliceToUint(bytes memory _bytes, uint256 _start) internal pure returns (uint256 x) {
require(_bytes.length >= _start + 32, "slicing out of range");
assembly {
x := mload(add(_bytes, add(0x20, _start)))
}
}
}