Contract Name:
FogRewardPool
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity 0.8.28;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
import "../interfaces/IWETH.sol";
import "../interfaces/IBasisAsset.sol";
import "../interfaces/IOracle.sol";
/**
* @title FogRewardPool
* @notice A staking reward pool where users deposit LP tokens to earn FOG.
* @dev FOG rewards are distributed over time (rewardPerSecond) to stakers. When harvesting, users must pay a fee in native Sonic,
* which is used for peg stabilization. In addition, this contract supports emergency withdrawal.
*/
contract FogRewardPool is ReentrancyGuard {
using SafeERC20 for IERC20;
/* ========== STATE VARIABLES ========== */
// Governance
address public operator;
// User info for stakers.
struct UserInfo {
uint256 amount; // LP tokens provided by the user.
uint256 rewardDebt; // Reward debt; used for reward calculations.
}
// Pool info for each LP token.
struct PoolInfo {
IERC20 token; // LP token contract.
uint256 allocPoint; // Allocation points for FOG distribution.
uint256 lastRewardTime; // Last timestamp FOG distribution occurred.
uint256 accFogPerShare; // Accumulated FOG per share (scaled by 1e18).
bool isStarted; // True if pool reward distribution has started.
}
// FOG token and price oracle.
address public fog;
IOracle public fogOracle;
uint256 public pegStabilityModuleFee = 2500; // 25% fee; set to 0 to disable.
uint256 public minClaimThreshold = 1e16; // Minimum claim threshold: 0.01 FOG.
address public pegStabilizationReserves; // Address to receive part of minted rewards (Collateral Pool).
// Wrapped Sonic instance for native Sonic conversion.
IWETH public wrappedSonic = IWETH(0x039e2fB66102314Ce7b64Ce5Ce3E5183bc94aD38);
// Pool and user accounting.
PoolInfo[] public poolInfo;
mapping(uint256 => mapping(address => UserInfo)) public userInfo;
mapping(uint256 => mapping(address => uint256)) public unclaimedRewards;
// Total allocation points across all pools.
uint256 public totalAllocPoint = 0;
// Mining schedule.
uint256 public poolStartTime;
uint256 public poolEndTime;
uint256 public rewardPerSecond = 0.00009512938 ether;
uint256 public runningTime = 730 days;
/* ========== EVENTS ========== */
event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
event RewardPaid(address indexed user, uint256 amount);
event SonicPaid(address indexed user, uint256 amount);
event UpdateRewardPerSecond(uint256 rewardPerSecond);
/* ========== CONSTRUCTOR ========== */
/**
* @notice Constructs the FogRewardPool.
* @param _fog Address of the FOG token.
* @param _pegStabilizationReserves Address for the Peg Stabilization Reserves.
* @param _poolStartTime Timestamp for when FOG mining begins.
*/
constructor(address _fog, address _pegStabilizationReserves, uint256 _poolStartTime) {
require(block.timestamp < _poolStartTime, "Pool cannot start in the past");
require(_fog != address(0), "Invalid FOG address");
require(_pegStabilizationReserves != address(0), "Invalid pegStabilizationReserves address");
fog = _fog;
pegStabilizationReserves = _pegStabilizationReserves;
poolStartTime = _poolStartTime;
poolEndTime = _poolStartTime + runningTime;
operator = msg.sender;
}
/**
* @notice Allow the contract to receive native Sonic.
*/
receive() external payable {}
/* ========== MODIFIERS ========== */
/**
* @dev Throws if called by any account other than the operator.
*/
modifier onlyOperator() {
require(operator == msg.sender, "FogRewardPool: caller is not the operator");
_;
}
/* ========== POOL MANAGEMENT ========== */
/**
* @notice Returns the number of pools.
* @return Number of pools.
*/
function poolLength() external view returns (uint256) {
return poolInfo.length;
}
/**
* @dev Ensures no duplicate pool exists for the same LP token.
* @param _token LP token address.
*/
function checkPoolDuplicate(IERC20 _token) internal view {
uint256 length = poolInfo.length;
for (uint256 pid = 0; pid < length; ++pid) {
require(poolInfo[pid].token != _token, "FogRewardPool: existing pool?");
}
}
/**
* @notice Adds a new LP pool.
* @param _allocPoint Allocation points for FOG distribution.
* @param _token LP token address.
* @param _lastRewardTime Custom last reward timestamp; if zero, it defaults to poolStartTime or current time.
*/
function add(uint256 _allocPoint, IERC20 _token, uint256 _lastRewardTime) public onlyOperator {
checkPoolDuplicate(_token);
massUpdatePools();
if (block.timestamp < poolStartTime) {
_lastRewardTime = (_lastRewardTime == 0 || _lastRewardTime < poolStartTime) ? poolStartTime : _lastRewardTime;
} else {
_lastRewardTime = (_lastRewardTime == 0 || _lastRewardTime < block.timestamp) ? block.timestamp : _lastRewardTime;
}
bool _isStarted = (_lastRewardTime <= poolStartTime) || (_lastRewardTime <= block.timestamp);
poolInfo.push(PoolInfo({token: _token, allocPoint: _allocPoint, lastRewardTime: _lastRewardTime, accFogPerShare: 0, isStarted: _isStarted}));
if (_isStarted) {
totalAllocPoint += _allocPoint;
}
}
/**
* @notice Updates allocation points for an existing pool.
* @param _pid Pool id.
* @param _allocPoint New allocation points.
*/
function set(uint256 _pid, uint256 _allocPoint) public onlyOperator {
massUpdatePools();
PoolInfo storage pool = poolInfo[_pid];
if (pool.isStarted) {
totalAllocPoint = totalAllocPoint - pool.allocPoint + _allocPoint;
}
pool.allocPoint = _allocPoint;
}
/**
* @notice Bulk updates allocation points for multiple pools.
* @param _pids Array of pool ids.
* @param _allocPoints Array of new allocation points.
*/
function bulkSet(uint256[] calldata _pids, uint256[] calldata _allocPoints) external onlyOperator {
require(_pids.length == _allocPoints.length, "FogRewardPool: invalid length");
for (uint256 i = 0; i < _pids.length; i++) {
set(_pids[i], _allocPoints[i]);
}
}
/* ========== VIEW FUNCTIONS ========== */
/**
* @notice Returns the pending FOG rewards for a user in a pool.
* @param _pid Pool id.
* @param _user User address.
* @return Pending FOG reward.
*/
function pendingReward(uint256 _pid, address _user) public view returns (uint256) {
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][_user];
uint256 accFogPerShare = pool.accFogPerShare;
uint256 tokenSupply = pool.token.balanceOf(address(this));
if (block.timestamp > pool.lastRewardTime && tokenSupply != 0) {
uint256 elapsed = block.timestamp - pool.lastRewardTime;
uint256 _fogReward = (elapsed * rewardPerSecond * pool.allocPoint) / totalAllocPoint;
accFogPerShare += (_fogReward * 1e18) / tokenSupply;
}
return unclaimedRewards[_pid][_user] + ((user.amount * accFogPerShare) / 1e18) - user.rewardDebt;
}
/**
* @notice Returns the total pending FOG rewards for a user across all pools.
* @param _user User address.
* @return Total pending rewards.
*/
function pendingAllRewards(address _user) public view returns (uint256) {
uint256 length = poolInfo.length;
uint256 totalPending;
for (uint256 pid = 0; pid < length; ++pid) {
totalPending += pendingReward(pid, _user);
}
return totalPending;
}
/**
* @notice Gets the FOG price in Sonic by querying the fogOracle.
* @return FOG price in Sonic.
*/
function getFogPriceInSonic() public view returns (uint256) {
return fogOracle.twap(address(fog), 1e18);
}
/**
* @notice Returns the native Sonic fee required to harvest pending rewards for a pool.
* @param _pid Pool id.
* @param _user User address.
* @return Fee in native Sonic.
*/
function getBribingSonicToHarvest(uint256 _pid, address _user) external view returns (uint256) {
uint256 pending = pendingReward(_pid, _user);
return (getFogPriceInSonic() * pending * pegStabilityModuleFee) / 1e22;
}
/**
* @notice Returns the total native Sonic fee to harvest all pending rewards for a user.
* @param _user User address.
* @return Total fee in native Sonic.
*/
function getBribingSonicToHarvestAll(address _user) external view returns (uint256) {
uint256 pending = pendingAllRewards(_user);
return (getFogPriceInSonic() * pending * pegStabilityModuleFee) / 1e22;
}
/* ========== UPDATE FUNCTIONS ========== */
/**
* @notice Updates reward variables for all pools.
*/
function massUpdatePools() public {
uint256 length = poolInfo.length;
for (uint256 pid = 0; pid < length; ++pid) {
updatePool(pid);
}
}
/**
* @notice Updates reward variables for a specific pool.
* @param _pid Pool id.
*/
function updatePool(uint256 _pid) private {
PoolInfo storage pool = poolInfo[_pid];
if (block.timestamp <= pool.lastRewardTime) {
return;
}
uint256 tokenSupply = pool.token.balanceOf(address(this));
if (tokenSupply == 0) {
pool.lastRewardTime = block.timestamp;
return;
}
if (!pool.isStarted) {
pool.isStarted = true;
totalAllocPoint += pool.allocPoint;
}
if (totalAllocPoint > 0) {
uint256 elapsed = block.timestamp - pool.lastRewardTime;
uint256 _fogReward = (elapsed * rewardPerSecond * pool.allocPoint) / totalAllocPoint;
pool.accFogPerShare += (_fogReward * 1e18) / tokenSupply;
}
pool.lastRewardTime = block.timestamp;
}
/* ========== USER FUNCTIONS ========== */
/**
* @notice Deposits LP tokens into a pool.
* @param _pid Pool id.
* @param _amount Amount of LP tokens to deposit.
*/
function deposit(uint256 _pid, uint256 _amount) public nonReentrant {
address _sender = msg.sender;
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][_sender];
updatePool(_pid);
if (user.amount > 0) {
uint256 _pending = (user.amount * pool.accFogPerShare) / 1e18 - user.rewardDebt;
if (_pending > 0) {
unclaimedRewards[_pid][_sender] += _pending;
}
}
if (_amount > 0) {
IERC20 _lpToken = IERC20(pool.token);
uint256 _before = _lpToken.balanceOf(address(this));
_lpToken.safeTransferFrom(_sender, address(this), _amount);
_amount = _lpToken.balanceOf(address(this)) - _before; // adjust for deflationary tokens
if (_amount > 0) {
user.amount += _amount;
}
}
user.rewardDebt = (user.amount * pool.accFogPerShare) / 1e18;
emit Deposit(_sender, _pid, _amount);
}
/**
* @notice Withdraws LP tokens from a pool.
* @param _pid Pool id.
* @param _amount Amount of LP tokens to withdraw.
*/
function withdraw(uint256 _pid, uint256 _amount) public payable nonReentrant {
address _sender = msg.sender;
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][_sender];
require(user.amount >= _amount, "withdraw: insufficient balance");
updatePool(_pid);
uint256 pending = (user.amount * pool.accFogPerShare) / 1e18 - user.rewardDebt;
if (pending > 0) {
unclaimedRewards[_pid][_sender] += pending;
}
if (_amount > 0) {
user.amount -= _amount;
pool.token.safeTransfer(_sender, _amount);
}
user.rewardDebt = (user.amount * pool.accFogPerShare) / 1e18;
emit Withdraw(_sender, _pid, _amount);
}
/**
* @notice Harvests pending FOG rewards for a specific pool.
* Users must pay a bribe fee in native Sonic, converted to Wrapped Sonic.
* @param _pid Pool id.
*/
function harvest(uint256 _pid) public payable nonReentrant {
address _sender = msg.sender;
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][_sender];
updatePool(_pid);
uint256 _pending = (user.amount * pool.accFogPerShare) / 1e18 - user.rewardDebt;
uint256 _rewardsToClaim = _pending + unclaimedRewards[_pid][_sender];
require(_rewardsToClaim >= minClaimThreshold, "Claim amount below minimum threshold");
if (_rewardsToClaim > 0) {
unclaimedRewards[_pid][_sender] = 0;
uint256 amountSonicToPay = 0;
if (pegStabilityModuleFee > 0) {
amountSonicToPay = (getFogPriceInSonic() * _rewardsToClaim * pegStabilityModuleFee) / 1e22;
require(msg.value >= amountSonicToPay, "insufficient sonic for PSM cost");
emit SonicPaid(_sender, amountSonicToPay);
} else {
require(msg.value == 0, "Invalid msg.value");
}
safeFogTransfer(_sender, _rewardsToClaim);
emit RewardPaid(_sender, _rewardsToClaim);
if (pegStabilityModuleFee > 0 && msg.value > amountSonicToPay) {
uint256 refundAmount = msg.value - amountSonicToPay;
(bool success, ) = _sender.call{value: refundAmount}("");
require(success, "Refund failed");
}
}
user.rewardDebt = (user.amount * pool.accFogPerShare) / 1e18;
}
/**
* @notice Harvests pending FOG rewards from all pools.
*/
function harvestAll() public payable nonReentrant {
address _sender = msg.sender;
uint256 length = poolInfo.length;
uint256 totalUserRewardsToClaim = 0;
for (uint256 pid = 0; pid < length; ++pid) {
PoolInfo storage pool = poolInfo[pid];
UserInfo storage user = userInfo[pid][_sender];
updatePool(pid);
uint256 _pending = (user.amount * pool.accFogPerShare) / 1e18 - user.rewardDebt;
uint256 _rewardsToClaim = _pending + unclaimedRewards[pid][_sender];
if (_rewardsToClaim > 0) {
unclaimedRewards[pid][_sender] = 0;
totalUserRewardsToClaim += _rewardsToClaim;
}
user.rewardDebt = (user.amount * pool.accFogPerShare) / 1e18;
}
require(totalUserRewardsToClaim >= minClaimThreshold, "Claim amount below minimum threshold");
if (totalUserRewardsToClaim > 0) {
uint256 amountSonicToPay = 0;
if (pegStabilityModuleFee > 0) {
amountSonicToPay = (getFogPriceInSonic() * totalUserRewardsToClaim * pegStabilityModuleFee) / 1e22;
require(msg.value >= amountSonicToPay, "insufficient sonic for PSM cost");
emit SonicPaid(_sender, amountSonicToPay);
} else {
require(msg.value == 0, "Invalid msg.value");
}
safeFogTransfer(_sender, totalUserRewardsToClaim);
emit RewardPaid(_sender, totalUserRewardsToClaim);
if (pegStabilityModuleFee > 0 && msg.value > amountSonicToPay) {
uint256 refundAmount = msg.value - amountSonicToPay;
(bool success, ) = _sender.call{value: refundAmount}("");
require(success, "Refund failed");
}
}
}
/**
* @notice Emergency withdrawal of LP tokens.
* @param _pid Pool id.
*/
function emergencyWithdraw(uint256 _pid) public nonReentrant {
PoolInfo storage pool = poolInfo[_pid];
UserInfo storage user = userInfo[_pid][msg.sender];
uint256 _amount = user.amount;
unclaimedRewards[_pid][msg.sender] = 0;
user.amount = 0;
user.rewardDebt = 0;
pool.token.safeTransfer(msg.sender, _amount);
emit EmergencyWithdraw(msg.sender, _pid, _amount);
}
/* ========== INTERNAL FUNCTIONS ========== */
/**
* @notice Safely transfers FOG tokens to a recipient. Mints additional tokens if the contract balance is insufficient.
* @param _to The recipient address.
* @param _amount The amount of FOG to transfer.
*/
function safeFogTransfer(address _to, uint256 _amount) internal {
uint256 _fogBal = IERC20(fog).balanceOf(address(this));
if (_fogBal < _amount) {
IBasisAsset(fog).mint(address(this), _amount - _fogBal);
}
_fogBal = IERC20(fog).balanceOf(address(this));
if (_fogBal > 0) {
if (_amount > _fogBal) {
IERC20(fog).safeTransfer(_to, _fogBal);
} else {
IERC20(fog).safeTransfer(_to, _amount);
}
}
}
/* ========== GOVERNANCE & ADMIN FUNCTIONS ========== */
function setOperator(address _operator) external onlyOperator {
require(_operator != address(0), "Invalid address");
operator = _operator;
}
function setPegStabilizationReserves(address _pegStabilizationReserves) public onlyOperator {
require(_pegStabilizationReserves != address(0), "Invalid address");
pegStabilizationReserves = _pegStabilizationReserves;
}
function setPegStabilityModuleFee(uint256 _pegStabilityModuleFee) external onlyOperator {
require(_pegStabilityModuleFee <= 5000, "Invalid fee"); // max 50%
pegStabilityModuleFee = _pegStabilityModuleFee;
}
function setFogOracle(address _fogOracle) external onlyOperator {
require(_fogOracle != address(0), "Invalid address");
fogOracle = IOracle(_fogOracle);
}
function setMinClaimThreshold(uint256 _minClaimThreshold) external onlyOperator {
require(_minClaimThreshold <= 1e18, "Invalid min claim threshold");
minClaimThreshold = _minClaimThreshold;
}
function setWSonic(IWETH _wrappedSonic) external onlyOperator {
require(address(_wrappedSonic) != address(0), "Invalid Wrapped Sonic address");
wrappedSonic = _wrappedSonic;
}
function setRewardPerSecond(uint256 _rewardPerSecond) external onlyOperator {
require(_rewardPerSecond <= 0.00019 ether, "Rate too high");
massUpdatePools();
rewardPerSecond = _rewardPerSecond;
emit UpdateRewardPerSecond(_rewardPerSecond);
}
/**
* @notice Allows the operator to recover unsupported tokens.
* @param _token The token to recover.
* @param amount The amount to recover.
* @param _to The recipient address.
*/
function governanceRecoverUnsupported(IERC20 _token, uint256 amount, address _to) external onlyOperator {
uint256 length = poolInfo.length;
for (uint256 pid = 0; pid < length; ++pid) {
PoolInfo storage pool = poolInfo[pid];
require(_token != pool.token, "Token cannot be pool token");
}
_token.safeTransfer(_to, amount);
}
/**
* @notice Collects all native Sonic held by this contract, wraps it into Wrapped Sonic, and transfers it to pegStabilizationReserves.
*/
function collectSonic() external {
require(address(wrappedSonic) != address(0), "wrappedSonic not set");
uint256 amount = address(this).balance;
require(amount > 0, "No Sonic balance to collect");
wrappedSonic.deposit{value: amount}();
IERC20(wrappedSonic).safeTransfer(pegStabilizationReserves, amount);
}
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.28;
interface IOracle {
function update() external;
function consult(address _token, uint256 _amountIn) external view returns (uint144 amountOut);
function twap(address _token, uint256 _amountIn) external view returns (uint144 _amountOut);
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.28;
interface IBasisAsset {
function mint(address recipient, uint256 amount) external returns (bool);
function burn(uint256 amount) external;
function burnFrom(address from, uint256 amount) external;
function isOperator() external returns (bool);
function operator() external view returns (address);
function transferOperator(address newOperator_) external;
function transferOwnership(address newOwner_) external;
function totalBurned() external view returns (uint256);
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity 0.8.28;
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
interface IWETH is IERC20 {
function deposit() external payable;
function withdraw(uint256 wad) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/ReentrancyGuard.sol)
pragma solidity ^0.8.20;
/**
* @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 EIP-1153 (transient storage) is available on the chain you're deploying at,
* consider using {ReentrancyGuardTransient} instead.
*
* 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;
/**
* @dev Unauthorized reentrant call.
*/
error ReentrancyGuardReentrantCall();
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() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be NOT_ENTERED
if (_status == ENTERED) {
revert ReentrancyGuardReentrantCall();
}
// Any calls to nonReentrant after this point will fail
_status = ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == ENTERED;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.2.0) (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.20;
import {IERC20} from "../IERC20.sol";
import {IERC1363} from "../../../interfaces/IERC1363.sol";
/**
* @title SafeERC20
* @dev Wrappers around ERC-20 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 {
/**
* @dev An operation with an ERC-20 token failed.
*/
error SafeERC20FailedOperation(address token);
/**
* @dev Indicates a failed `decreaseAllowance` request.
*/
error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease);
/**
* @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*/
function safeTransfer(IERC20 token, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value)));
}
/**
* @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
* calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
*/
function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
_callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value)));
}
/**
* @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful.
*
* IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
* smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
* this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
* that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
*/
function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
uint256 oldAllowance = token.allowance(address(this), spender);
forceApprove(token, spender, oldAllowance + value);
}
/**
* @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no
* value, non-reverting calls are assumed to be successful.
*
* IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
* smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
* this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
* that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
*/
function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal {
unchecked {
uint256 currentAllowance = token.allowance(address(this), spender);
if (currentAllowance < requestedDecrease) {
revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease);
}
forceApprove(token, spender, currentAllowance - requestedDecrease);
}
}
/**
* @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
* non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
* to be set to zero before setting it to a non-zero value, such as USDT.
*
* NOTE: If the token implements ERC-7674, this function will not modify any temporary allowance. This function
* only sets the "standard" allowance. Any temporary allowance will remain active, in addition to the value being
* set here.
*/
function forceApprove(IERC20 token, address spender, uint256 value) internal {
bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value));
if (!_callOptionalReturnBool(token, approvalCall)) {
_callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0)));
_callOptionalReturn(token, approvalCall);
}
}
/**
* @dev Performs an {ERC1363} transferAndCall, with a fallback to the simple {ERC20} transfer if the target has no
* code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
* targeting contracts.
*
* Reverts if the returned value is other than `true`.
*/
function transferAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
if (to.code.length == 0) {
safeTransfer(token, to, value);
} else if (!token.transferAndCall(to, value, data)) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @dev Performs an {ERC1363} transferFromAndCall, with a fallback to the simple {ERC20} transferFrom if the target
* has no code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
* targeting contracts.
*
* Reverts if the returned value is other than `true`.
*/
function transferFromAndCallRelaxed(
IERC1363 token,
address from,
address to,
uint256 value,
bytes memory data
) internal {
if (to.code.length == 0) {
safeTransferFrom(token, from, to, value);
} else if (!token.transferFromAndCall(from, to, value, data)) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @dev Performs an {ERC1363} approveAndCall, with a fallback to the simple {ERC20} approve if the target has no
* code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
* targeting contracts.
*
* NOTE: When the recipient address (`to`) has no code (i.e. is an EOA), this function behaves as {forceApprove}.
* Opposedly, when the recipient address (`to`) has code, this function only attempts to call {ERC1363-approveAndCall}
* once without retrying, and relies on the returned value to be true.
*
* Reverts if the returned value is other than `true`.
*/
function approveAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
if (to.code.length == 0) {
forceApprove(token, to, value);
} else if (!token.approveAndCall(to, value, data)) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @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).
*
* This is a variant of {_callOptionalReturnBool} that reverts if call fails to meet the requirements.
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
uint256 returnSize;
uint256 returnValue;
assembly ("memory-safe") {
let success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
// bubble errors
if iszero(success) {
let ptr := mload(0x40)
returndatacopy(ptr, 0, returndatasize())
revert(ptr, returndatasize())
}
returnSize := returndatasize()
returnValue := mload(0)
}
if (returnSize == 0 ? address(token).code.length == 0 : returnValue != 1) {
revert SafeERC20FailedOperation(address(token));
}
}
/**
* @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).
*
* This is a variant of {_callOptionalReturn} that silently catches all reverts and returns a bool instead.
*/
function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
bool success;
uint256 returnSize;
uint256 returnValue;
assembly ("memory-safe") {
success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
returnSize := returndatasize()
returnValue := mload(0)
}
return success && (returnSize == 0 ? address(token).code.length > 0 : returnValue == 1);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC-20 standard as defined in the ERC.
*/
interface IERC20 {
/**
* @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);
/**
* @dev Returns the value of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the value of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 value) 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 a `value` amount of tokens 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 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the
* allowance mechanism. `value` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 value) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (interfaces/IERC1363.sol)
pragma solidity ^0.8.20;
import {IERC20} from "./IERC20.sol";
import {IERC165} from "./IERC165.sol";
/**
* @title IERC1363
* @dev Interface of the ERC-1363 standard as defined in the https://eips.ethereum.org/EIPS/eip-1363[ERC-1363].
*
* Defines an extension interface for ERC-20 tokens that supports executing code on a recipient contract
* after `transfer` or `transferFrom`, or code on a spender contract after `approve`, in a single transaction.
*/
interface IERC1363 is IERC20, IERC165 {
/*
* Note: the ERC-165 identifier for this interface is 0xb0202a11.
* 0xb0202a11 ===
* bytes4(keccak256('transferAndCall(address,uint256)')) ^
* bytes4(keccak256('transferAndCall(address,uint256,bytes)')) ^
* bytes4(keccak256('transferFromAndCall(address,address,uint256)')) ^
* bytes4(keccak256('transferFromAndCall(address,address,uint256,bytes)')) ^
* bytes4(keccak256('approveAndCall(address,uint256)')) ^
* bytes4(keccak256('approveAndCall(address,uint256,bytes)'))
*/
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferAndCall(address to, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @param data Additional data with no specified format, sent in call to `to`.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param from The address which you want to send tokens from.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferFromAndCall(address from, address to, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
* and then calls {IERC1363Receiver-onTransferReceived} on `to`.
* @param from The address which you want to send tokens from.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
* @param data Additional data with no specified format, sent in call to `to`.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function transferFromAndCall(address from, address to, uint256 value, bytes calldata data) external returns (bool);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function approveAndCall(address spender, uint256 value) external returns (bool);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
* @param data Additional data with no specified format, sent in call to `spender`.
* @return A boolean value indicating whether the operation succeeded unless throwing.
*/
function approveAndCall(address spender, uint256 value, bytes calldata data) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (interfaces/IERC165.sol)
pragma solidity ^0.8.20;
import {IERC165} from "../utils/introspection/IERC165.sol";
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (interfaces/IERC20.sol)
pragma solidity ^0.8.20;
import {IERC20} from "../token/ERC20/IERC20.sol";
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/introspection/IERC165.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC-165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[ERC].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[ERC section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}