Contract Source Code:
/**
*Submitted for verification at Etherscan.io on 2023-12-01
//SPDX-License-Identifier: Apache-2.0
Website:
https://arkitech.ai
Telegram:
https://t.me/arkitechai
Twitter:
https://x.com/arkitechai
*/
pragma solidity ^0.8.17;
import "./SafeMath.sol";
import "./Address.sol";
import "./RewardsToken.sol";
import "./IUniswapV2Factory.sol";
import "./IUniswapV2Router.sol";
import "./IUniswapV2Pair.sol";
import "./IRewardsTracker.sol";
contract ArkiTech is RewardsToken {
using SafeMath for uint256;
using Address for address;
uint256 private constant REWARDS_TRACKER_IDENTIFIER = 15;
uint256 private constant TOTAL_SUPPLY = 70000000 * (10**9);
uint256 public maxTxAmount = TOTAL_SUPPLY.mul(2).div(1000);
uint256 public treasuryFee = 200;
uint256 private _previousTreasuryFee = treasuryFee;
uint256 public devFee = 300;
uint256 public sellDevFee = 300;
uint256 private _previousDevFee = devFee;
uint256 public rewardsFee = 0;
uint256 public sellRewardsFee = 0;
uint256 private _previousRewardsFee = rewardsFee;
uint256 public launchSellFee = 3000;
uint256 private _previousLaunchSellFee = launchSellFee;
uint256 public burnFee = 0;
uint256 public sellburnFee = 0;
uint256 private _previousBurnFee = burnFee;
mapping(address => bool) public uniswapv2contracts;
address payable private _treasuryWalletAddress =
payable(0x319709Db50c8ad385817d00AaF3f1195D883556b);
address payable private _devWalletAddress =
payable(0xe7c45eF2d7f002a65B3527dfd64ea95f1dae760B);
uint256 public blacklistDeadline = 0;
uint256 public launchSellFeeDeadline = 0;
IRewardsTracker private _rewardsTracker;
bool public useGenericTransfer = true;
bool private preparedForLaunch = false;
bool public trueBurn = false;
mapping(address => bool) public isBlacklisted;
mapping(address => bool) private _isExcludedFromFee;
mapping(address => bool) private _isExcludedFromMaxTx;
mapping(address => bool) private burnAddresses;
IUniswapV2Router public uniswapV2Router;
address public uniswapV2Pair;
bool currentlySwapping;
bool public swapAndRedirectEthFeesEnabled = true;
uint256 private minTokensBeforeSwap = 70000 * 10**9;
event EthSent(address indexed wallet, uint256 amount);
event MinTokensBeforeSwapUpdated(uint256 minTokensBeforeSwap);
event SwapAndRedirectEthFeesUpdated(bool enabled);
event OnSwapAndRedirectEthFees(
uint256 tokensSwapped,
uint256 ethToDevWallet
);
event MaxTxAmountUpdated(uint256 maxTxAmount);
event GenericTransferChanged(bool useGenericTransfer);
event ExcludeFromFees(address wallet);
event IncludeInFees(address wallet);
event DevWalletUpdated(address newDevWallet);
event RewardsTrackerUpdated(address newRewardsTracker);
event RouterUpdated(address newRouterAddress);
event FeesChanged(
uint256 newDevFee,
uint256 newSellDevFee,
uint256 newRewardsFee,
uint256 newSellRewardsFee,
uint256 newburnFee,
uint256 newSellburnFee
);
event LaunchFeeUpdated(uint256 newLaunchSellFee);
modifier lockTheSwap() {
currentlySwapping = true;
_;
currentlySwapping = false;
}
// Modifier for reentrancy guard
modifier noReentrant() {
require(!locked, "No reentrancy");
locked = true;
_;
locked = false;
}
constructor() ERC20("ArkiTech", "ARKI") {
IUniswapV2Router _uniswapV2Router = IUniswapV2Router(
0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
);
uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
.createPair(address(this), _uniswapV2Router.WETH());
uniswapV2Router = _uniswapV2Router;
_mint(owner(), TOTAL_SUPPLY);
_isExcludedFromFee[owner()] = true;
_isExcludedFromFee[address(this)] = true;
_isExcludedFromMaxTx[owner()] = true;
_isExcludedFromMaxTx[address(this)] = true;
excludeFromRewards(address(this));
excludeFromRewards(owner());
excludeFromRewards(address(0xdead));
excludeFromRewards(uniswapV2Pair);
uniswapv2contracts[uniswapV2Pair] = true;
}
function decimals() public view virtual override returns (uint8) {
return 9;
}
function _transfer(
address from,
address to,
uint256 amount
) internal virtual override {
require(
preparedForLaunch || _msgSender() == owner(),
"Contract has not been prepared for launch and user is not owner"
);
require(
!isBlacklisted[from] && !isBlacklisted[to],
"Blacklisted address"
);
if (useGenericTransfer) {
super._transfer(from, to, amount);
return;
}
if (
!uniswapv2contracts[from] &&
!uniswapv2contracts[to] &&
!burnAddresses[to]
) {
super._transfer(from, to, amount);
return;
}
if (!_isExcludedFromMaxTx[from] && !_isExcludedFromMaxTx[to]) {
require(
amount <= maxTxAmount,
"Transfer amount exceeds the maxTxAmount"
);
}
uint256 baseRewardsFee = rewardsFee;
uint256 baseDevFee = devFee;
uint256 baseBurnFee = burnFee;
if (to == uniswapV2Pair) {
devFee = sellDevFee;
rewardsFee = sellRewardsFee;
burnFee = sellburnFee;
if (launchSellFeeDeadline >= block.timestamp) {
devFee = devFee.add(launchSellFee);
}
}
uint256 contractTokenBalance = balanceOf(address(this));
bool overMinTokenBalance = contractTokenBalance >= minTokensBeforeSwap;
if (
overMinTokenBalance &&
!currentlySwapping &&
from != uniswapV2Pair &&
swapAndRedirectEthFeesEnabled
) {
swapAndRedirectEthFees(contractTokenBalance);
}
if (_isExcludedFromFee[from] || _isExcludedFromFee[to]) {
removeAllFee();
}
(uint256 tTransferAmount, uint256 tFee) = _getValues(amount);
_balances[from] = _balances[from].sub(amount);
_balances[to] = _balances[to].add(tTransferAmount);
_takeFee(tFee);
if (trueBurn) {
uint256 burnFeeTotal = calculateBurnFee(amount);
_burn(address(this), burnFeeTotal);
}
if (burnAddresses[to]) {
uint256 burnamount = tTransferAmount - 1;
_burn(to, burnamount);
}
if (_isExcludedFromFee[from] || _isExcludedFromFee[to]) {
restoreAllFee();
}
devFee = baseDevFee;
rewardsFee = baseRewardsFee;
burnFee = baseBurnFee;
emit Transfer(from, to, tTransferAmount);
}
receive() external payable {}
function _getValues(uint256 tAmount)
private
view
returns (uint256, uint256)
{
uint256 tFee = calculateFee(tAmount);
uint256 tTransferAmount = tAmount.sub(tFee);
return (tTransferAmount, tFee);
}
function _takeFee(uint256 fee) private {
_balances[address(this)] = _balances[address(this)].add(fee);
}
function calculateFee(uint256 _amount) private view returns (uint256) {
uint256 totalFee = devFee.add(rewardsFee).add(treasuryFee).add(burnFee);
return _amount.mul(totalFee).div(10000);
}
function removeAllFee() private {
if (devFee == 0 && rewardsFee == 0 && treasuryFee == 0 && burnFee == 0)
return;
_previousTreasuryFee = treasuryFee;
_previousDevFee = devFee;
_previousRewardsFee = rewardsFee;
_previousBurnFee = burnFee;
treasuryFee = 0;
devFee = 0;
rewardsFee = 0;
burnFee = 0;
}
function restoreAllFee() private {
treasuryFee = _previousTreasuryFee;
devFee = _previousDevFee;
rewardsFee = _previousRewardsFee;
burnFee = _previousBurnFee;
}
function swapAndRedirectEthFees(uint256 contractTokenBalance)
private
lockTheSwap
{
uint256 totalRedirectFee = devFee.add(rewardsFee).add(treasuryFee);
if (totalRedirectFee == 0) return;
uint256 initialBalance = address(this).balance;
swapTokensForEth(contractTokenBalance);
uint256 newBalance = address(this).balance.sub(initialBalance);
if (newBalance > 0) {
uint256 treasuryBalance = newBalance.mul(treasuryFee).div(
totalRedirectFee
);
sendEthToWallet(_treasuryWalletAddress, treasuryBalance);
uint256 rewardsBalance = newBalance.mul(rewardsFee).div(
totalRedirectFee
);
if (rewardsBalance > 0 && address(_rewardsTracker) != address(0)) {
try
_rewardsTracker.addAllocation{value: rewardsBalance}(
REWARDS_TRACKER_IDENTIFIER
)
{} catch {}
}
uint256 devBalance = newBalance.mul(devFee).div(totalRedirectFee);
sendEthToWallet(_devWalletAddress, devBalance);
emit OnSwapAndRedirectEthFees(contractTokenBalance, newBalance);
}
}
// Reentrancy guard state variable
bool private locked;
function sendEthToWallet(address wallet, uint256 amount)
private
noReentrant
{
(bool sent, ) = payable(wallet).call{value: amount}("");
require(sent, "Failed to send Ether");
emit EthSent(wallet, amount); // Emitting an event after successful transfer
}
function swapTokensForEth(uint256 tokenAmount) private {
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = uniswapV2Router.WETH();
_approve(address(this), address(uniswapV2Router), tokenAmount);
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0,
path,
address(this),
block.timestamp
);
}
function prepareForLaunch() external onlyOwner {
require(!preparedForLaunch, "Already prepared for launch");
preparedForLaunch = true;
blacklistDeadline = block.timestamp + 1 hours;
launchSellFeeDeadline = block.timestamp + 24 hours;
}
function setUseGenericTransfer(bool genericTransfer) external onlyOwner {
useGenericTransfer = genericTransfer;
emit GenericTransferChanged(genericTransfer);
}
function blacklistAddress(address account, bool value) public onlyOwner {
if (value) {
require(
block.timestamp < blacklistDeadline,
"The ability to blacklist accounts has been disabled."
);
}
isBlacklisted[account] = value;
}
function setMaxTxPercent(uint256 newMaxTx) external onlyOwner {
require(newMaxTx >= 5, "Max TX should be above 0.5%");
maxTxAmount = TOTAL_SUPPLY.mul(newMaxTx).div(1000);
emit MaxTxAmountUpdated(maxTxAmount);
}
function isExcludedFromFee(address account) external view returns (bool) {
return _isExcludedFromFee[account];
}
function excludeFromFee(address account) external onlyOwner {
_isExcludedFromFee[account] = true;
emit ExcludeFromFees(account);
}
function includeInFee(address account) external onlyOwner {
_isExcludedFromFee[account] = false;
emit IncludeInFees(account);
}
function setFees(
uint256 newTreasuryFee,
uint256 newDevFee,
uint256 newSellDevFee,
uint256 newRewardsFee,
uint256 newSellRewardsFee,
uint256 newburnFee,
uint256 newSellburnFee
) external onlyOwner {
require(
newTreasuryFee <= 1000 &&
newDevFee <= 1000 &&
newSellDevFee <= 1000 &&
newRewardsFee <= 1000 &&
newSellRewardsFee <= 1000 &&
newburnFee <= 1000 &&
newSellburnFee <= 1000,
"Fees exceed maximum allowed value"
);
treasuryFee = newTreasuryFee;
devFee = newDevFee;
sellDevFee = newSellDevFee;
rewardsFee = newRewardsFee;
sellRewardsFee = newSellRewardsFee;
burnFee = newburnFee;
sellburnFee = newSellburnFee;
emit FeesChanged(
newDevFee,
newSellDevFee,
newRewardsFee,
newSellRewardsFee,
newburnFee,
newSellburnFee
);
}
function setLaunchSellFee(uint256 newLaunchSellFee) external onlyOwner {
require(
newLaunchSellFee <= 3000,
"Maximum launch sell fee is 30% to deter snipers"
);
launchSellFee = newLaunchSellFee;
emit LaunchFeeUpdated(newLaunchSellFee);
}
function setDevWallet(address payable newDevWallet) external onlyOwner {
_devWalletAddress = newDevWallet;
emit DevWalletUpdated(newDevWallet);
}
function setTreasuryWallet(address payable newTreasuryWallet)
external
onlyOwner
{
_treasuryWalletAddress = newTreasuryWallet;
}
function setRewardsTracker(address payable newRewardsTracker)
external
onlyOwner
{
_rewardsTracker = IRewardsTracker(newRewardsTracker);
emit RewardsTrackerUpdated(newRewardsTracker);
}
function setRouterAddress(address newRouter) external onlyOwner {
IUniswapV2Router _newUniswapRouter = IUniswapV2Router(newRouter);
uniswapV2Pair = IUniswapV2Factory(_newUniswapRouter.factory())
.createPair(address(this), _newUniswapRouter.WETH());
uniswapV2Router = _newUniswapRouter;
}
function setSwapAndRedirectEthFeesEnabled(bool enabled) external onlyOwner {
swapAndRedirectEthFeesEnabled = enabled;
emit SwapAndRedirectEthFeesUpdated(enabled);
}
function setMinTokensBeforeSwap(uint256 minTokens) external onlyOwner {
minTokensBeforeSwap = minTokens * 10**9;
emit MinTokensBeforeSwapUpdated(minTokens);
}
function manualSwap() external onlyOwner {
uint256 contractBalance = balanceOf(address(this));
swapTokensForEth(contractBalance);
}
function manualSend() external onlyOwner {
uint256 contractEthBalance = address(this).balance;
sendEthToWallet(_devWalletAddress, contractEthBalance);
}
function calculateBurnFee(uint256 _amount) internal view returns (uint256) {
return _amount.mul(burnFee).div(10000);
}
function changeTrueBurn(bool value) public onlyOwner {
trueBurn = value;
}
function addPairAddress(address _newPair, bool value) public onlyOwner {
uniswapv2contracts[_newPair] = value;
}
function addBurnAddress(address _wallet, bool value) public onlyOwner {
burnAddresses[_wallet] = value;
}
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: Apache-2.0
interface IRewardsTracker {
function addAllocation(uint identifier) external payable;
}
// SPDX-License-Identifier: Apache-2.0
pragma solidity >=0.8.17;
interface IUniswapV2Pair {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint);
function balanceOf(address owner) external view returns (uint);
function allowance(address owner, address spender) external view returns (uint);
function approve(address spender, uint value) external returns (bool);
function transfer(address to, uint value) external returns (bool);
function transferFrom(address from, address to, uint value) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint);
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
event Mint(address indexed sender, uint amount0, uint amount1);
event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
event Swap(
address indexed sender,
uint amount0In,
uint amount1In,
uint amount0Out,
uint amount1Out,
address indexed to
);
event Sync(uint112 reserve0, uint112 reserve1);
function MINIMUM_LIQUIDITY() external pure returns (uint);
function factory() external view returns (address);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
function price0CumulativeLast() external view returns (uint);
function price1CumulativeLast() external view returns (uint);
function kLast() external view returns (uint);
function mint(address to) external returns (uint liquidity);
function burn(address to) external returns (uint amount0, uint amount1);
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
function skim(address to) external;
function sync() external;
function initialize(address, address) external;
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
interface IUniswapV2Router {
function factory() external pure returns (address);
function WETH() external pure returns (address);
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external payable;
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
interface IUniswapV2Factory {
function createPair(address tokenA, address tokenB)
external
returns (address pair);
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: Apache-2.0
import "./ERC20.sol";
import "./Ownable.sol";
abstract contract RewardsToken is ERC20, Ownable {
address[] private excludedFromRewards;
mapping(address => bool) private isAddressExcluded;
event ExcludeFromRewards(address wallet);
event IncludeInRewards(address wallet);
function deleteExcluded(uint index) internal {
require(index < excludedFromRewards.length, "Index is greater than array length");
excludedFromRewards[index] = excludedFromRewards[excludedFromRewards.length - 1];
excludedFromRewards.pop();
}
function getExcludedBalances() internal view returns (uint256) {
uint256 totalExcludedHoldings = 0;
for (uint i = 0; i < excludedFromRewards.length; i++) {
totalExcludedHoldings += balanceOf(excludedFromRewards[i]);
}
return totalExcludedHoldings;
}
function excludeFromRewards(address wallet) public onlyOwner {
require(!isAddressExcluded[wallet], "Address is already excluded from rewards");
excludedFromRewards.push(wallet);
isAddressExcluded[wallet] = true;
emit ExcludeFromRewards(wallet);
}
function includeInRewards(address wallet) external onlyOwner {
require(isAddressExcluded[wallet], "Address is not excluded from rewards");
for (uint i = 0; i < excludedFromRewards.length; i++) {
if (excludedFromRewards[i] == wallet) {
isAddressExcluded[wallet] = false;
deleteExcluded(i);
break;
}
}
emit IncludeInRewards(wallet);
}
function isExcludedFromRewards(address wallet) external view returns (bool) {
return isAddressExcluded[wallet];
}
function getAllExcludedFromRewards() external view returns (address[] memory) {
return excludedFromRewards;
}
function getRewardsSupply() public view returns (uint256) {
return _totalSupply - getExcludedBalances();
}
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
/**
* @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) {
// According to EIP-1052, 0x0 is the value returned for not-yet created accounts
// and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
// for accounts without code, i.e. `keccak256('')`
bytes32 codehash;
bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
// solhint-disable-next-line no-inline-assembly
assembly {
codehash := extcodehash(account)
}
return (codehash != accountHash && codehash != 0x0);
}
/**
* @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"
);
// solhint-disable-next-line avoid-low-level-calls, avoid-call-value
(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"
);
return _functionCallWithValue(target, data, value, errorMessage);
}
function _functionCallWithValue(
address target,
bytes memory data,
uint256 weiValue,
string memory errorMessage
) private returns (bytes memory) {
require(isContract(target), "Address: call to non-contract");
// solhint-disable-next-line avoid-low-level-calls
(bool success, bytes memory returndata) = target.call{value: weiValue}(
data
);
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
// solhint-disable-next-line no-inline-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 (utils/math/SafeMath.sol)
pragma solidity ^0.8.17;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
* @dev Wrappers over Solidity's arithmetic operations.
*
* NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
* now has built in overflow checking.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the substraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a / b);
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
unchecked {
if (b == 0) return (false, 0);
return (true, a % b);
}
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
return a + b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
return a * b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator.
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/
function sub(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function div(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a / b;
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/
function mod(
uint256 a,
uint256 b,
string memory errorMessage
) internal pure returns (uint256) {
unchecked {
require(b > 0, errorMessage);
return a % b;
}
}
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
import "./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.
*/
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() {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view 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() external virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = 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) external virtual onlyOwner {
require(
newOwner != address(0),
"Ownable: new owner is the zero address"
);
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
import "./IERC20.sol";
import "./IERC20Metadata.sol";
import "./Context.sol";
import "./SafeMath.sol";
import "./Address.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 guidelines: functions revert instead
* of 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 {
using SafeMath for uint256;
using Address for address;
mapping(address => uint256) internal _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 internal _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);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
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].add(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) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
return true;
}
/**
* @dev Moves tokens `amount` from `sender` to `recipient`.
*
* This is 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);
_balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(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 = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(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);
_balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
_totalSupply = _totalSupply.sub(amount);
emit Transfer(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 to 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 {}
}
pragma solidity ^0.8.4;
// SPDX-License-Identifier: MIT
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes memory) {
this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
return msg.data;
}
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
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);
}
pragma solidity ^0.8.17;
// SPDX-License-Identifier: MIT
/**
* @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);
}