Circuit Breaker Solidity Ethereum smart contract example

circuit-breaker-solidity.sol

bool private stopped = false;
address private owner;

modifier isAdmin() {
    if(msg.sender != owner) {
        throw;
    }
    _
}

function toggleContractActive() isAdmin public
{
    // You can add an additional modifier that restricts stopping a contract to be based on another action, such as a vote of users
    stopped = !stopped;
}

modifier stopInEmergency { if (!stopped) _ }
modifier onlyInEmergency { if (stopped) _ }

function deposit() stopInEmergency public
{
    // some code
}

function withdraw() onlyInEmergency public
{
    // some code
}