updateShareholder in FeeSplitter.sol can be implemented more efficiently

[code423n4]

Handle

0x0x0x

Vulnerability details

Explanation

updateShareholder in FeeSplitter.sol can be implemented more efficiently. The updated version consumes less gas and also has the second require statement earlier, which reduces the gas cost in case the statement of second require is not fullfilled.

FeeSplitter.sol : L166-174:

    function updateShareholder(uint256 _accountIndex, uint256 _weight) external onlyOwner {
        require(_accountIndex + 1 <= shareholders.length, "FeeSplitter: INVALID_ACCOUNT_INDEX");
        uint256 _totalWeights = totalWeights;
        _totalWeights -= shareholders[_accountIndex].weight;
        shareholders[_accountIndex].weight = _weight;
        _totalWeights += _weight;
        require(_totalWeights > 0, "FeeSplitter: TOTAL_WEIGHTS_ZERO");
        totalWeights = _totalWeights;
    }

can be replaced with:

    function updateShareholder(uint256 _accountIndex, uint256 _weight) external onlyOwner {
        require(_accountIndex + 1 <= shareholders.length, "FeeSplitter: INVALID_ACCOUNT_INDEX");
        totalWeights = totalWeights + _weight - shareholders[_accountIndex].weight;
        require(_totalWeights > 0, "FeeSplitter: TOTAL_WEIGHTS_ZERO");
        shareholders[_accountIndex].weight = _weight;
    }

Tools Used

Manual analysis