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PullPayment.sol
43 lines (33 loc) · 1.03 KB
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PullPayment.sol
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pragma solidity ^0.4.18;
import "../math/SafeMath.sol";
/**
* @title PullPayment
* @dev Base contract supporting async send for pull payments. Inherit from this
* contract and use asyncSend instead of send.
*/
contract PullPayment {
using SafeMath for uint256;
mapping(address => uint256) public payments;
uint256 public totalPayments;
/**
* @dev withdraw accumulated balance, called by payee.
*/
function withdrawPayments() public {
address payee = msg.sender;
uint256 payment = payments[payee];
require(payment != 0);
require(this.balance >= payment);
totalPayments = totalPayments.sub(payment);
payments[payee] = 0;
assert(payee.send(payment));
}
/**
* @dev Called by the payer to store the sent amount as credit to be pulled.
* @param dest The destination address of the funds.
* @param amount The amount to transfer.
*/
function asyncSend(address dest, uint256 amount) internal {
payments[dest] = payments[dest].add(amount);
totalPayments = totalPayments.add(amount);
}
}