Files
dodo-contractV2/contracts/lib/UniversalERC20.sol
2020-11-10 18:38:34 +08:00

75 lines
2.2 KiB
Solidity

/*
Copyright 2020 DODO ZOO.
SPDX-License-Identifier: Apache-2.0
*/
pragma solidity 0.6.9;
import {SafeMath} from "./SafeMath.sol";
import {IERC20} from "../intf/IERC20.sol";
import {SafeERC20} from "./SafeERC20.sol";
library UniversalERC20 {
using SafeMath for uint256;
using SafeERC20 for IERC20;
IERC20 private constant ZERO_ADDRESS = IERC20(0x0000000000000000000000000000000000000000);
IERC20 private constant ETH_ADDRESS = IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
function universalTransfer(IERC20 token, address to, uint256 amount) internal {
universalTransfer(token, to, amount, false);
}
function universalTransfer(IERC20 token, address to, uint256 amount, bool mayFail) internal returns(bool) {
if (amount == 0) {
return true;
}
if (token == ZERO_ADDRESS || token == ETH_ADDRESS) {
if (mayFail) {
return address(uint160(to)).send(amount);
} else {
address(uint160(to)).transfer(amount);
return true;
}
} else {
token.safeTransfer(to, amount);
return true;
}
}
function universalApprove(IERC20 token, address to, uint256 amount) internal {
if (token != ZERO_ADDRESS && token != ETH_ADDRESS) {
token.safeApprove(to, amount);
}
}
function universalTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
if (amount == 0) {
return;
}
if (token == ZERO_ADDRESS || token == ETH_ADDRESS) {
require(from == msg.sender && msg.value >= amount, "msg.value is zero");
if (to != address(this)) {
address(uint160(to)).transfer(amount);
}
if (msg.value > amount) {
msg.sender.transfer(msg.value.sub(amount));
}
} else {
token.safeTransferFrom(from, to, amount);
}
}
function universalBalanceOf(IERC20 token, address who) internal view returns (uint256) {
if (token == ZERO_ADDRESS || token == ETH_ADDRESS) {
return who.balance;
} else {
return token.balanceOf(who);
}
}
}