Contract Name:
AuraBalVault
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity 0.8.11;
import { GenericUnionVault } from "./GenericVault.sol";
interface IAuraBalStrategy {
function harvest(uint256 _minAmountOut) external returns (uint256 harvested);
}
/**
* @title AuraBalVault
* @author llama.airforce
*/
contract AuraBalVault is GenericUnionVault {
bool public isHarvestPermissioned = true;
mapping(address => bool) public authorizedHarvesters;
constructor(address _token, address _virtualRewardFactory) GenericUnionVault(_token, _virtualRewardFactory) {}
/// @notice Sets whether only whitelisted addresses can harvest
/// @param _status Whether or not harvests are permissioned
function setHarvestPermissions(bool _status) external onlyOwner {
isHarvestPermissioned = _status;
}
/// @notice Adds or remove an address from the harvesters' whitelist
/// @param _harvester address of the authorized harvester
/// @param _authorized Whether to add or remove harvester
function updateAuthorizedHarvesters(address _harvester, bool _authorized) external onlyOwner {
authorizedHarvesters[_harvester] = _authorized;
}
/// @notice Claim rewards and swaps them to auraBAL for restaking
/// @param _minAmountOut - min amount of auraBAL to receive for harvest
/// @dev Can be called by whitelisted account or anyone against an auraBal incentive
/// @dev Harvest logic in the strategy contract
/// @dev Harvest can be called even if permissioned when last staker is
/// withdrawing from the vault.
function harvest(uint256 _minAmountOut) public {
require(
!isHarvestPermissioned || authorizedHarvesters[msg.sender] || totalSupply() == 0,
"permissioned harvest"
);
uint256 _harvested = IAuraBalStrategy(strategy).harvest(_minAmountOut);
emit Harvest(msg.sender, _harvested);
}
/// @notice Claim rewards and swaps them to auraBAL for restaking
/// @dev No slippage protection, swapping for auraBAL
function harvest() public override {
harvest(0);
}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.11;
import { Ownable } from "@openzeppelin/contracts-0.8/access/Ownable.sol";
import { SafeERC20 } from "@openzeppelin/contracts-0.8/token/ERC20/utils/SafeERC20.sol";
import { ERC20 } from "@openzeppelin/contracts-0.8/token/ERC20/ERC20.sol";
import { IERC20 } from "@openzeppelin/contracts-0.8/token/ERC20/IERC20.sol";
import { ReentrancyGuard } from "@openzeppelin/contracts-0.8/security/ReentrancyGuard.sol";
import { IERC4626 } from "../interfaces/IERC4626.sol";
import { IStrategy } from "../interfaces/IStrategy.sol";
import { IBasicRewards } from "../interfaces/IBasicRewards.sol";
import { IVirtualRewards, IVirtualRewardFactory } from "../interfaces/IVirtualRewards.sol";
/**
* @title GenericUnionVault
* @author llama.airforce -> AuraFinance
* @notice Changes:
* - remove withdraw penalty
* - remove platform fee
* - add extra rewards logic
*/
contract GenericUnionVault is ERC20, IERC4626, Ownable, ReentrancyGuard {
using SafeERC20 for IERC20;
uint256 public withdrawalPenalty = 100;
uint256 public constant MAX_WITHDRAWAL_PENALTY = 150;
uint256 public constant FEE_DENOMINATOR = 10000;
address public immutable underlying;
address public immutable virtualRewardFactory;
address public strategy;
address[] public extraRewards;
mapping(address => bool) public isExtraReward;
event WithdrawalPenaltyUpdated(uint256 _penalty);
event Harvest(address indexed _caller, uint256 _value);
event CallerIncentiveUpdated(uint256 _incentive);
event StrategySet(address indexed _strategy);
event ExtraRewardAdded(address indexed _reward, address extraReward);
event ExtraRewardCleared(address indexed _reward);
constructor(address _token, address _virtualRewardFactory)
ERC20(
string(abi.encodePacked("Staked ", ERC20(_token).name())),
string(abi.encodePacked("stk", ERC20(_token).symbol()))
)
{
underlying = _token;
virtualRewardFactory = _virtualRewardFactory;
}
/// @notice Updates the withdrawal penalty
/// @param _penalty - the amount of the new penalty (in BIPS)
function setWithdrawalPenalty(uint256 _penalty) external onlyOwner {
require(_penalty <= MAX_WITHDRAWAL_PENALTY);
withdrawalPenalty = _penalty;
emit WithdrawalPenaltyUpdated(_penalty);
}
/// @notice Set the address of the strategy contract
/// @dev Can only be set once
/// @param _strategy - address of the strategy contract
function setStrategy(address _strategy) external onlyOwner notToZeroAddress(_strategy) {
require(strategy == address(0), "Strategy already set");
strategy = _strategy;
emit StrategySet(_strategy);
}
/// @notice Count of extra rewards
function extraRewardsLength() external view returns (uint256) {
return extraRewards.length;
}
/// @notice Add extra reward contract
/// @param _reward VirtualBalanceRewardPool address
/// @return bool success
function addExtraReward(address _reward) external onlyOwner notToZeroAddress(_reward) returns (bool) {
require(extraRewards.length < 12, "too many rewards");
require(!isExtraReward[_reward], "reward exists");
require(strategy != address(0), "strategy not set");
address extraReward = IVirtualRewardFactory(virtualRewardFactory).createVirtualReward(
address(this),
_reward,
strategy
);
address reward = IVirtualRewards(extraReward).rewardToken();
extraRewards.push(extraReward);
isExtraReward[reward] = true;
emit ExtraRewardAdded(reward, extraReward);
return true;
}
/// @notice Clear extra rewards array
function clearExtraRewards() external onlyOwner {
uint256 len = extraRewards.length;
for (uint256 i = 0; i < len; i++) {
address reward = IVirtualRewards(extraRewards[i]).rewardToken();
isExtraReward[reward] = false;
emit ExtraRewardCleared(reward);
}
delete extraRewards;
}
/// @notice Query the amount currently staked
/// @return total - the total amount of tokens staked
function totalUnderlying() public view returns (uint256 total) {
return IStrategy(strategy).totalUnderlying();
}
/// @notice Returns the amount of underlying a user can claim
/// @param user - address whose claimable amount to query
/// @return amount - claimable amount
/// @dev Does not account for penalties and fees
function balanceOfUnderlying(address user) external view returns (uint256 amount) {
require(totalSupply() > 0, "No users");
return ((balanceOf(user) * totalUnderlying()) / totalSupply());
}
/// @notice Deposit user funds in the autocompounder and mints tokens
/// representing user's share of the pool in exchange
/// @param _amount - the amount of underlying to deposit
/// @return _shares - the amount of shares issued
function deposit(uint256 _amount, address _receiver)
public
notToZeroAddress(_receiver)
nonReentrant
returns (uint256 _shares)
{
require(_amount > 0, "Deposit too small");
uint256 _before = totalUnderlying();
// Issues shares in proportion of deposit to pool amount
uint256 shares = 0;
if (totalSupply() == 0) {
shares = _amount;
} else {
shares = (_amount * totalSupply()) / _before;
}
// Stake into extra rewards before we update the users
// balancers and update totalSupply/totalUnderlying
for (uint256 i = 0; i < extraRewards.length; i++) {
IBasicRewards(extraRewards[i]).stake(_receiver, shares);
}
IERC20(underlying).safeTransferFrom(msg.sender, strategy, _amount);
IStrategy(strategy).stake(_amount);
_mint(_receiver, shares);
emit Deposit(msg.sender, _receiver, _amount, shares);
return shares;
}
/// @notice Unstake underlying in proportion to the amount of shares sent
/// @param _shares - the number of shares sent
/// @return _withdrawable - the withdrawable underlying amount
function _withdraw(address _from, uint256 _shares) internal returns (uint256 _withdrawable) {
require(totalSupply() > 0);
// Computes the amount withdrawable based on the number of shares sent
uint256 amount = (_shares * totalUnderlying()) / totalSupply();
// Burn the shares before retrieving tokens
_burn(_from, _shares);
// If user is last to withdraw, harvest before exit
if (totalSupply() == 0) {
harvest();
IStrategy(strategy).withdraw(totalUnderlying());
_withdrawable = IERC20(underlying).balanceOf(address(this));
}
// Otherwise compute share and unstake
else {
_withdrawable = amount;
// Substract a small withdrawal fee to prevent users "timing"
// the harvests. The fee stays staked and is therefore
// redistributed to all remaining participants.
uint256 _penalty = _getWithdrawalPenalty(_withdrawable);
_withdrawable = _withdrawable - _penalty;
IStrategy(strategy).withdraw(_withdrawable);
}
return _withdrawable;
}
/// @notice Get the withdraw penalty amount
/// @param _amount Amount of asset
/// @return penalty amount
function _getWithdrawalPenalty(uint256 _amount) internal view returns (uint256) {
return (_amount * withdrawalPenalty) / FEE_DENOMINATOR;
}
/// @notice Unstake underlying token in proportion to the amount of shares sent
/// @param _shares - the number of shares sent
/// @return withdrawn - the amount of underlying returned to the user
function redeem(
uint256 _shares,
address _receiver,
address _owner
) public notToZeroAddress(_receiver) notToZeroAddress(_owner) nonReentrant returns (uint256 withdrawn) {
// Check allowance if owner if not sender
if (msg.sender != _owner) {
uint256 currentAllowance = allowance(_owner, msg.sender);
require(currentAllowance >= _shares, "ERC4626: redeem exceeds allowance");
_approve(_owner, msg.sender, currentAllowance - _shares);
}
// Withdraw from extra rewards
for (uint256 i = 0; i < extraRewards.length; i++) {
IBasicRewards(extraRewards[i]).withdraw(_owner, _shares);
}
// Withdraw requested amount of underlying
uint256 _withdrawable = _withdraw(_owner, _shares);
// And sends back underlying to user
IERC20(underlying).safeTransfer(_receiver, _withdrawable);
emit Withdraw(msg.sender, _receiver, _owner, _withdrawable, _shares);
return _withdrawable;
}
/// @notice Claim rewards and swaps them to FXS for restaking
/// @dev Can be called by anyone against an incentive in FXS
/// @dev Harvest logic in the strategy contract
function harvest() public virtual {
uint256 _harvested = IStrategy(strategy).harvest();
emit Harvest(msg.sender, _harvested);
}
modifier notToZeroAddress(address _to) {
require(_to != address(0), "Invalid address!");
_;
}
/* --------------------------------------------------------------
* ERC20 hooks
----------------------------------------------------------------- */
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal override {
// Withdraw extra rewards for the "from" address to update their earned
// amount when updateReward is called
for (uint256 i = 0; i < extraRewards.length; i++) {
IBasicRewards(extraRewards[i]).withdraw(from, amount);
}
// Stake extra rewards for the "to" address
for (uint256 i = 0; i < extraRewards.length; i++) {
IBasicRewards(extraRewards[i]).stake(to, amount);
}
}
/* --------------------------------------------------------------
* EIP-4626 functions
----------------------------------------------------------------- */
/// @notice The address of the underlying token used for the Vault for
/// accounting, depositing, and withdrawing.
function asset() public view returns (address) {
return underlying;
}
/// @notice Total amount of the underlying asset that is “managed” by Vault.
function totalAssets() public view returns (uint256) {
return totalUnderlying();
}
/// @notice The amount of shares that the Vault would exchange for the amount
/// of assets provided, in an ideal scenario where all the conditions are met.
function convertToShares(uint256 _assets) public view returns (uint256) {
return _convertToShares(_assets, false);
}
/// @param _assets The amount of underlying assets to be convert to vault shares.
/// @param isRoundUp bool to indicate round up the shares
/// @dev isRoundUp is used to round-up the shares amount for withdraw and previewWithdraw
function _convertToShares(uint256 _assets, bool isRoundUp) internal view virtual returns (uint256 shares) {
uint256 totalShares = totalSupply();
if (totalShares == 0) {
shares = _assets; // 1:1 value of shares and assets
} else {
uint256 totalAssetsMem = totalUnderlying();
shares = (_assets * totalShares) / totalAssetsMem;
// Round Up if needed
if (isRoundUp && mulmod(_assets, totalShares, totalAssetsMem) > 0) {
shares += 1;
}
}
}
/// @notice The amount of assets that the Vault would exchange for the amount
/// of shares provided, in an ideal scenario where all the conditions are met.
function convertToAssets(uint256 _shares) public view returns (uint256) {
return _convertToAssets(_shares, false);
}
/// @param _shares The amount of vault shares to be converted to the underlying assets.
/// @param isRoundUp bool to indicate round up the assets
/// @dev isRoundUp is used to round-up the assets amount for mint and previewMint
function _convertToAssets(uint256 _shares, bool isRoundUp) internal view virtual returns (uint256 assets) {
uint256 totalShares = totalSupply();
if (totalShares == 0) {
assets = _shares; // 1:1 value of shares and assets
} else {
uint256 totalAssetsMem = totalUnderlying();
assets = (_shares * totalAssetsMem) / totalShares;
// Round Up if needed
if (isRoundUp && mulmod(_shares, totalAssetsMem, totalShares) > 0) {
assets += 1;
}
}
}
/// @notice Maximum amount of the underlying asset that can be deposited into
/// the Vault for the receiver, through a deposit call.
function maxDeposit(address) public pure returns (uint256) {
return type(uint256).max;
}
/// @notice Allows an on-chain or off-chain user to simulate the effects of
/// their deposit at the current block, given current on-chain conditions.
function previewDeposit(uint256 _assets) public view returns (uint256) {
return _convertToShares(_assets, false);
}
/// @notice Maximum amount of shares that can be minted from the Vault
/// for the receiver, through a mint call.
function maxMint(address) public pure returns (uint256) {
return type(uint256).max;
}
/// @notice Allows an on-chain or off-chain user to simulate the effects of
/// their mint at the current block, given current on-chain conditions.
function previewMint(uint256 _shares) public view returns (uint256) {
return _convertToAssets(_shares, true);
}
/// @notice Mints exactly shares Vault shares to receiver by depositing
/// assets of underlying tokens.
function mint(uint256 _shares, address _receiver) public returns (uint256) {
uint256 assets = previewMint(_shares);
return deposit(assets, _receiver);
}
/// @notice Maximum amount of the underlying asset that can be withdrawn
/// from the owner balance in the Vault, through a withdraw call.
function maxWithdraw(address _owner) public view returns (uint256) {
return previewRedeem(maxRedeem((_owner)));
}
/// @notice Allows an on-chain or off-chain user to simulate the effects
/// of their withdrawal at the current block, given current on-chain conditions.
function previewWithdraw(uint256 _assets) public view returns (uint256) {
_assets = ((FEE_DENOMINATOR * _assets) / (FEE_DENOMINATOR - withdrawalPenalty));
return _convertToShares(_assets, true);
}
/// @notice Burns shares from owner and sends exactly assets of
/// underlying tokens to receiver.
function withdraw(
uint256 _assets,
address _receiver,
address _owner
) public returns (uint256) {
uint256 shares = previewWithdraw(_assets);
return redeem(shares, _receiver, _owner);
}
/// @notice Maximum amount of Vault shares that can be redeemed from the
/// owner balance in the Vault, through a redeem call.
function maxRedeem(address _owner) public view returns (uint256) {
return balanceOf(_owner);
}
/// @notice Allows an on-chain or off-chain user to simulate the effects of
/// their redeemption at the current block, given current on-chain conditions.
function previewRedeem(uint256 _shares) public view returns (uint256) {
uint256 amount = _convertToAssets(_shares, false);
uint256 penalty = _getWithdrawalPenalty(amount);
return amount - penalty;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../utils/Address.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
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));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(
IERC20 token,
address spender,
uint256 value
) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
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) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) {
// Return data is optional
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20, IERC20Metadata {
mapping(address => uint256) private _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* The default value of {decimals} is 18. To select a different value for
* {decimals} you should overload it.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless this function is
* overridden;
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual override returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual override returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* Requirements:
*
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
* - the caller must have allowance for ``sender``'s tokens of at least
* `amount`.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) public virtual override returns (bool) {
_transfer(sender, recipient, amount);
uint256 currentAllowance = _allowances[sender][_msgSender()];
require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
unchecked {
_approve(sender, _msgSender(), currentAllowance - amount);
}
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
uint256 currentAllowance = _allowances[_msgSender()][spender];
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(_msgSender(), spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `amount` of tokens from `sender` to `recipient`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(
address sender,
address recipient,
uint256 amount
) internal virtual {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(sender, recipient, amount);
uint256 senderBalance = _balances[sender];
require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[sender] = senderBalance - amount;
}
_balances[recipient] += amount;
emit Transfer(sender, recipient, amount);
_afterTokenTransfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
_balances[account] += amount;
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
}
_totalSupply -= amount;
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(
address owner,
address spender,
uint256 amount
) internal virtual {
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);
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `sender` to `recipient` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.11;
import { IERC20 } from "@openzeppelin/contracts-0.8/token/ERC20/IERC20.sol";
import { IERC20Metadata } from "@openzeppelin/contracts-0.8/token/ERC20/extensions/IERC20Metadata.sol";
/**
* @dev Interface of the ERC4626 "Tokenized Vault Standard", as defined in
* https://eips.ethereum.org/EIPS/eip-4626[ERC-4626].
* @author OpenZeppelin
* Fork of OpenZeppelin Contracts (last updated v4.8.0) (interfaces/IERC4626.sol)
*/
interface IERC4626 is IERC20, IERC20Metadata {
event Deposit(address indexed sender, address indexed owner, uint256 assets, uint256 shares);
event Withdraw(
address indexed sender,
address indexed receiver,
address indexed owner,
uint256 assets,
uint256 shares
);
/**
* @dev Returns the address of the underlying token used for the Vault for accounting, depositing, and withdrawing.
*
* - MUST be an ERC-20 token contract.
* - MUST NOT revert.
*/
function asset() external view returns (address assetTokenAddress);
/**
* @dev Returns the total amount of the underlying asset that is “managed” by Vault.
*
* - SHOULD include any compounding that occurs from yield.
* - MUST be inclusive of any fees that are charged against assets in the Vault.
* - MUST NOT revert.
*/
function totalAssets() external view returns (uint256 totalManagedAssets);
/**
* @dev Returns the amount of shares that the Vault would exchange for the amount of assets provided, in an ideal
* scenario where all the conditions are met.
*
* - MUST NOT be inclusive of any fees that are charged against assets in the Vault.
* - MUST NOT show any variations depending on the caller.
* - MUST NOT reflect slippage or other on-chain conditions, when performing the actual exchange.
* - MUST NOT revert.
*
* NOTE: This calculation MAY NOT reflect the “per-user” price-per-share, and instead should reflect the
* “average-user’s” price-per-share, meaning what the average user should expect to see when exchanging to and
* from.
*/
function convertToShares(uint256 assets) external view returns (uint256 shares);
/**
* @dev Returns the amount of assets that the Vault would exchange for the amount of shares provided, in an ideal
* scenario where all the conditions are met.
*
* - MUST NOT be inclusive of any fees that are charged against assets in the Vault.
* - MUST NOT show any variations depending on the caller.
* - MUST NOT reflect slippage or other on-chain conditions, when performing the actual exchange.
* - MUST NOT revert.
*
* NOTE: This calculation MAY NOT reflect the “per-user” price-per-share, and instead should reflect the
* “average-user’s” price-per-share, meaning what the average user should expect to see when exchanging to and
* from.
*/
function convertToAssets(uint256 shares) external view returns (uint256 assets);
/**
* @dev Returns the maximum amount of the underlying asset that can be deposited into the Vault for the receiver,
* through a deposit call.
*
* - MUST return a limited value if receiver is subject to some deposit limit.
* - MUST return 2 ** 256 - 1 if there is no limit on the maximum amount of assets that may be deposited.
* - MUST NOT revert.
*/
function maxDeposit(address receiver) external view returns (uint256 maxAssets);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their deposit at the current block, given
* current on-chain conditions.
*
* - MUST return as close to and no more than the exact amount of Vault shares that would be minted in a deposit
* call in the same transaction. I.e. deposit should return the same or more shares as previewDeposit if called
* in the same transaction.
* - MUST NOT account for deposit limits like those returned from maxDeposit and should always act as though the
* deposit would be accepted, regardless if the user has enough tokens approved, etc.
* - MUST be inclusive of deposit fees. Integrators should be aware of the existence of deposit fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToShares and previewDeposit SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by depositing.
*/
function previewDeposit(uint256 assets) external view returns (uint256 shares);
/**
* @dev Mints shares Vault shares to receiver by depositing exactly amount of underlying tokens.
*
* - MUST emit the Deposit event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
* deposit execution, and are accounted for during deposit.
* - MUST revert if all of assets cannot be deposited (due to deposit limit being reached, slippage, the user not
* approving enough underlying tokens to the Vault contract, etc).
*
* NOTE: most implementations will require pre-approval of the Vault with the Vault’s underlying asset token.
*/
function deposit(uint256 assets, address receiver) external returns (uint256 shares);
/**
* @dev Returns the maximum amount of the Vault shares that can be minted for the receiver, through a mint call.
* - MUST return a limited value if receiver is subject to some mint limit.
* - MUST return 2 ** 256 - 1 if there is no limit on the maximum amount of shares that may be minted.
* - MUST NOT revert.
*/
function maxMint(address receiver) external view returns (uint256 maxShares);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their mint at the current block, given
* current on-chain conditions.
*
* - MUST return as close to and no fewer than the exact amount of assets that would be deposited in a mint call
* in the same transaction. I.e. mint should return the same or fewer assets as previewMint if called in the
* same transaction.
* - MUST NOT account for mint limits like those returned from maxMint and should always act as though the mint
* would be accepted, regardless if the user has enough tokens approved, etc.
* - MUST be inclusive of deposit fees. Integrators should be aware of the existence of deposit fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToAssets and previewMint SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by minting.
*/
function previewMint(uint256 shares) external view returns (uint256 assets);
/**
* @dev Mints exactly shares Vault shares to receiver by depositing amount of underlying tokens.
*
* - MUST emit the Deposit event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the mint
* execution, and are accounted for during mint.
* - MUST revert if all of shares cannot be minted (due to deposit limit being reached, slippage, the user not
* approving enough underlying tokens to the Vault contract, etc).
*
* NOTE: most implementations will require pre-approval of the Vault with the Vault’s underlying asset token.
*/
function mint(uint256 shares, address receiver) external returns (uint256 assets);
/**
* @dev Returns the maximum amount of the underlying asset that can be withdrawn from the owner balance in the
* Vault, through a withdraw call.
*
* - MUST return a limited value if owner is subject to some withdrawal limit or timelock.
* - MUST NOT revert.
*/
function maxWithdraw(address owner) external view returns (uint256 maxAssets);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their withdrawal at the current block,
* given current on-chain conditions.
*
* - MUST return as close to and no fewer than the exact amount of Vault shares that would be burned in a withdraw
* call in the same transaction. I.e. withdraw should return the same or fewer shares as previewWithdraw if
* called
* in the same transaction.
* - MUST NOT account for withdrawal limits like those returned from maxWithdraw and should always act as though
* the withdrawal would be accepted, regardless if the user has enough shares, etc.
* - MUST be inclusive of withdrawal fees. Integrators should be aware of the existence of withdrawal fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToShares and previewWithdraw SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by depositing.
*/
function previewWithdraw(uint256 assets) external view returns (uint256 shares);
/**
* @dev Burns shares from owner and sends exactly assets of underlying tokens to receiver.
*
* - MUST emit the Withdraw event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
* withdraw execution, and are accounted for during withdraw.
* - MUST revert if all of assets cannot be withdrawn (due to withdrawal limit being reached, slippage, the owner
* not having enough shares, etc).
*
* Note that some implementations will require pre-requesting to the Vault before a withdrawal may be performed.
* Those methods should be performed separately.
*/
function withdraw(
uint256 assets,
address receiver,
address owner
) external returns (uint256 shares);
/**
* @dev Returns the maximum amount of Vault shares that can be redeemed from the owner balance in the Vault,
* through a redeem call.
*
* - MUST return a limited value if owner is subject to some withdrawal limit or timelock.
* - MUST return balanceOf(owner) if owner is not subject to any withdrawal limit or timelock.
* - MUST NOT revert.
*/
function maxRedeem(address owner) external view returns (uint256 maxShares);
/**
* @dev Allows an on-chain or off-chain user to simulate the effects of their redeemption at the current block,
* given current on-chain conditions.
*
* - MUST return as close to and no more than the exact amount of assets that would be withdrawn in a redeem call
* in the same transaction. I.e. redeem should return the same or more assets as previewRedeem if called in the
* same transaction.
* - MUST NOT account for redemption limits like those returned from maxRedeem and should always act as though the
* redemption would be accepted, regardless if the user has enough shares, etc.
* - MUST be inclusive of withdrawal fees. Integrators should be aware of the existence of withdrawal fees.
* - MUST NOT revert.
*
* NOTE: any unfavorable discrepancy between convertToAssets and previewRedeem SHOULD be considered slippage in
* share price or some other type of condition, meaning the depositor will lose assets by redeeming.
*/
function previewRedeem(uint256 shares) external view returns (uint256 assets);
/**
* @dev Burns exactly shares from owner and sends assets of underlying tokens to receiver.
*
* - MUST emit the Withdraw event.
* - MAY support an additional flow in which the underlying tokens are owned by the Vault contract before the
* redeem execution, and are accounted for during redeem.
* - MUST revert if all of shares cannot be redeemed (due to withdrawal limit being reached, slippage, the owner
* not having enough shares, etc).
*
* NOTE: some implementations will require pre-requesting to the Vault before a withdrawal may be performed.
* Those methods should be performed separately.
*/
function redeem(
uint256 shares,
address receiver,
address owner
) external returns (uint256 assets);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.11;
interface IStrategy {
function harvest() external returns (uint256 harvested);
function harvest(uint256 _minAmountOut) external returns (uint256 harvested);
function totalUnderlying() external view returns (uint256 total);
function stake(uint256 _amount) external;
function withdraw(uint256 _amount) external;
function setApprovals() external;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.11;
interface IBasicRewards {
function stakeFor(address, uint256) external returns (bool);
function balanceOf(address) external view returns (uint256);
function totalSupply() external view returns (uint256);
function earned(address) external view returns (uint256);
function withdrawAll(bool) external returns (bool);
function withdraw(uint256, bool) external returns (bool);
function withdraw(address, uint256) external;
function withdrawAndUnwrap(uint256 amount, bool claim) external returns (bool);
function getReward() external returns (bool);
function stake(uint256) external returns (bool);
function stake(address, uint256) external;
function extraRewards(uint256) external view returns (address);
function exit() external returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.11;
interface IVirtualRewardFactory {
function createVirtualReward(
address,
address,
address
) external returns (address);
}
interface IVirtualRewards {
function queueNewRewards(uint256) external;
function rewardToken() external view returns (address);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
pragma solidity ^0.8.0;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}