Contract Source Code:
File 1 of 1 : yVault
pragma solidity ^0.5.17;
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address recipient, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
interface IDetailed {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
}
contract Context {
constructor () internal { }
// solhint-disable-previous-line no-empty-blocks
function _msgSender() internal view returns (address payable) {
return msg.sender;
}
function _msgData() internal view returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
contract ERC20 is Context, IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowances;
uint256 private _totalSupply;
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
function balanceOf(address account) public view returns (uint256) {
return _balances[account];
}
function transfer(address recipient, uint256 amount) public returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
function allowance(address owner, address spender) public view returns (uint256) {
return _allowances[owner][spender];
}
function approve(address spender, uint256 amount) public returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
function transferFrom(address sender, address recipient, uint256 amount) public returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
return true;
}
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
return true;
}
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
return true;
}
function _transfer(address sender, address recipient, uint256 amount) internal {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
function _mint(address account, uint256 amount) internal {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
function _burn(address account, uint256 amount) internal {
require(account != address(0), "ERC20: burn from the zero address");
_balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
_totalSupply = _totalSupply.sub(amount);
emit Transfer(account, address(0), amount);
}
function _approve(address owner, address spender, uint256 amount) internal {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, _msgSender(), _allowances[account][_msgSender()].sub(amount, "ERC20: burn amount exceeds allowance"));
}
}
library SafeMath {
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, errorMessage);
uint256 c = a / b;
return c;
}
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
library Address {
function isContract(address account) internal view returns (bool) {
bytes32 codehash;
bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
// solhint-disable-next-line no-inline-assembly
assembly { codehash := extcodehash(account) }
return (codehash != 0x0 && codehash != accountHash);
}
function toPayable(address account) internal pure returns (address payable) {
return address(uint160(account));
}
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
// solhint-disable-next-line avoid-call-value
(bool success, ) = recipient.call.value(amount)("");
require(success, "Address: unable to send value, recipient may have reverted");
}
}
library SafeERC20 {
using SafeMath for uint256;
using Address for address;
function safeTransfer(IERC20 token, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
function safeApprove(IERC20 token, address spender, uint256 value) internal {
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).add(value);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function callOptionalReturn(IERC20 token, bytes memory data) private {
require(address(token).isContract(), "SafeERC20: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = address(token).call(data);
require(success, "SafeERC20: low-level call failed");
if (returndata.length > 0) { // Return data is optional
// solhint-disable-next-line max-line-length
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
interface Controller {
function withdraw(address, uint) external;
function balanceOf(address) external view returns (uint);
function earn(address, uint) external;
}
contract yVault is ERC20 {
using SafeERC20 for IERC20;
using Address for address;
using SafeMath for uint256;
IERC20 public token;
uint public min = 9990;
uint public constant max = 10000;
address public governance;
address public controller;
string public name;
string public symbol;
uint8 public decimals;
constructor (address _token, address _controller) public {
name = string(abi.encodePacked("yearn ", IDetailed(_token).name()));
symbol = string(abi.encodePacked("yv", IDetailed(_token).symbol()));
decimals = IDetailed(_token).decimals();
token = IERC20(_token);
governance = msg.sender;
controller = _controller;
}
function setName(string calldata _name) external {
require(msg.sender == governance, "!governance");
name = _name;
}
function setSymbol(string calldata _symbol) external {
require(msg.sender == governance, "!governance");
symbol = _symbol;
}
function balance() public view returns (uint) {
return token.balanceOf(address(this))
.add(Controller(controller).balanceOf(address(token)));
}
function setMin(uint _min) external {
require(msg.sender == governance, "!governance");
min = _min;
}
function setGovernance(address _governance) public {
require(msg.sender == governance, "!governance");
governance = _governance;
}
function setController(address _controller) public {
require(msg.sender == governance, "!governance");
controller = _controller;
}
// Custom logic in here for how much the vault allows to be borrowed
// Sets minimum required on-hand to keep small withdrawals cheap
function available() public view returns (uint) {
return token.balanceOf(address(this)).mul(min).div(max);
}
function earn() public {
uint _bal = available();
token.safeTransfer(controller, _bal);
Controller(controller).earn(address(token), _bal);
}
function depositAll() external {
deposit(token.balanceOf(msg.sender));
}
function deposit(uint _amount) public {
uint _pool = balance();
uint _before = token.balanceOf(address(this));
token.safeTransferFrom(msg.sender, address(this), _amount);
uint _after = token.balanceOf(address(this));
_amount = _after.sub(_before); // Additional check for deflationary tokens
uint shares = 0;
if (totalSupply() == 0) {
shares = _amount;
} else {
shares = (_amount.mul(totalSupply())).div(_pool);
}
_mint(msg.sender, shares);
}
function withdrawAll() external {
withdraw(balanceOf(msg.sender));
}
// No rebalance implementation for lower fees and faster swaps
function withdraw(uint _shares) public {
uint r = (balance().mul(_shares)).div(totalSupply());
_burn(msg.sender, _shares);
// Check balance
uint b = token.balanceOf(address(this));
if (b < r) {
uint _withdraw = r.sub(b);
Controller(controller).withdraw(address(token), _withdraw);
uint _after = token.balanceOf(address(this));
uint _diff = _after.sub(b);
if (_diff < _withdraw) {
r = b.add(_diff);
}
}
token.safeTransfer(msg.sender, r);
}
function getPricePerFullShare() public view returns (uint) {
return balance().mul(1e18).div(totalSupply());
}
}