Files
openzeppelin-contracts/contracts/ReentrancyGuard.sol
2018-01-15 16:11:45 -05:00

33 lines
872 B
Solidity

pragma solidity ^0.4.18;
/**
* @title Helps contracts guard agains reentrancy attacks.
* @author Remco Bloemen <remco@2π.com>
* @notice If you mark a function `nonReentrant`, you should also
* mark it `external`.
*/
contract ReentrancyGuard {
/**
* @dev We use a single lock for the whole contract.
*/
bool private reentrancy_lock = false;
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* @notice If you mark a function `nonReentrant`, you should also
* mark it `external`. Calling one nonReentrant function from
* another is not supported. Instead, you can implement a
* `private` function doing the actual work, and a `external`
* wrapper marked as `nonReentrant`.
*/
modifier nonReentrant() {
require(!reentrancy_lock);
reentrancy_lock = true;
_;
reentrancy_lock = false;
}
}