Contract Name:
StandardToken
Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity 0.8.13;
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
interface IUniswapV2Router01 {
function factory() external pure returns (address);
function WETH() external pure returns (address);
function addLiquidity(
address tokenA,
address tokenB,
uint256 amountADesired,
uint256 amountBDesired,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
)
external
returns (
uint256 amountA,
uint256 amountB,
uint256 liquidity
);
function addLiquidityETH(
address token,
uint256 amountTokenDesired,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
)
external
payable
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
);
function removeLiquidity(
address tokenA,
address tokenB,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
) external returns (uint256 amountA, uint256 amountB);
function removeLiquidityETH(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) external returns (uint256 amountToken, uint256 amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountA, uint256 amountB);
function removeLiquidityETHWithPermit(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountToken, uint256 amountETH);
function swapExactTokensForTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapTokensForExactTokens(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapExactETHForTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable returns (uint256[] memory amounts);
function swapTokensForExactETH(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapExactTokensForETH(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapETHForExactTokens(
uint256 amountOut,
address[] calldata path,
address to,
uint256 deadline
) external payable returns (uint256[] memory amounts);
function quote(
uint256 amountA,
uint256 reserveA,
uint256 reserveB
) external pure returns (uint256 amountB);
function getAmountOut(
uint256 amountIn,
uint256 reserveIn,
uint256 reserveOut
) external pure returns (uint256 amountOut);
function getAmountIn(
uint256 amountOut,
uint256 reserveIn,
uint256 reserveOut
) external pure returns (uint256 amountIn);
function getAmountsOut(uint256 amountIn, address[] calldata path)
external
view
returns (uint256[] memory amounts);
function getAmountsIn(uint256 amountOut, address[] calldata path)
external
view
returns (uint256[] memory amounts);
}
interface IUniswapV2Router02 is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) external returns (uint256 amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountETH);
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
}
interface IUniswapV2Pair {
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
event Transfer(address indexed from, address indexed to, uint256 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 (uint256);
function balanceOf(address owner) external view returns (uint256);
function allowance(address owner, address spender)
external
view
returns (uint256);
function approve(address spender, uint256 value) external returns (bool);
function transfer(address to, uint256 value) external returns (bool);
function transferFrom(
address from,
address to,
uint256 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 (uint256);
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
event Mint(address indexed sender, uint256 amount0, uint256 amount1);
event Burn(
address indexed sender,
uint256 amount0,
uint256 amount1,
address indexed to
);
event Swap(
address indexed sender,
uint256 amount0In,
uint256 amount1In,
uint256 amount0Out,
uint256 amount1Out,
address indexed to
);
event Sync(uint112 reserve0, uint112 reserve1);
function MINIMUM_LIQUIDITY() external pure returns (uint256);
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 (uint256);
function price1CumulativeLast() external view returns (uint256);
function kLast() external view returns (uint256);
function mint(address to) external returns (uint256 liquidity);
function burn(address to)
external
returns (uint256 amount0, uint256 amount1);
function swap(
uint256 amount0Out,
uint256 amount1Out,
address to,
bytes calldata data
) external;
function skim(address to) external;
function sync() external;
function initialize(address, address) external;
}
interface IUniswapV2Factory {
event PairCreated(
address indexed token0,
address indexed token1,
address pair,
uint256
);
function feeTo() external view returns (address);
function feeToSetter() external view returns (address);
function getPair(address tokenA, address tokenB)
external
view
returns (address pair);
function allPairs(uint256) external view returns (address pair);
function allPairsLength() external view returns (uint256);
function createPair(address tokenA, address tokenB)
external
returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
function INIT_CODE_PAIR_HASH() external view returns (bytes32);
}
interface IUniswapV2Caller {
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
address router,
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
uint256 deadline
) external;
}
interface IFee {
function payFee(
uint256 _tokenType
) external payable;
}
contract StandardToken is ERC20, Ownable {
IUniswapV2Caller public constant uniswapV2Caller =
IUniswapV2Caller(0x1CcFE8c40eF259566433716002E379dFfFbf5a3e);
IFee public constant feeContract = IFee(0xfd6439AEfF9d2389856B7486b9e74a6DacaDcDCe);
uint8 private _decimals;
///////////////////////////////////////////////////////////////////////////
address public baseTokenForPair;
bool private inSwapAndLiquify;
uint16 public sellLiquidityFee;
uint16 public buyLiquidityFee;
uint16 public sellMarketingFee;
uint16 public buyMarketingFee;
address public marketingWallet;
bool public isMarketingFeeBaseToken;
uint256 public minAmountToTakeFee;
uint256 public maxWallet;
uint256 public maxTransactionAmount;
IUniswapV2Router02 public mainRouter;
address public mainPair;
mapping(address => bool) public isExcludedFromMaxTransactionAmount;
mapping(address => bool) public isExcludedFromFee;
mapping(address => bool) public automatedMarketMakerPairs;
uint256 private _liquidityFeeTokens;
uint256 private _marketingFeeTokens;
event UpdateLiquidityFee(
uint16 newSellLiquidityFee,
uint16 newBuyLiquidityFee,
uint16 oldSellLiquidityFee,
uint16 oldBuyLiquidityFee
);
event UpdateMarketingFee(
uint16 newSellMarketingFee,
uint16 newBuyMarketingFee,
uint16 oldSellMarketingFee,
uint16 oldBuyMarketingFee
);
event UpdateMarketingWallet(
address indexed newMarketingWallet,
bool newIsMarketingFeeBaseToken,
address indexed oldMarketingWallet,
bool oldIsMarketingFeeBaseToken
);
event ExcludedFromMaxTransactionAmount(address indexed account, bool isExcluded);
event UpdateMinAmountToTakeFee(uint256 newMinAmountToTakeFee, uint256 oldMinAmountToTakeFee);
event SetAutomatedMarketMakerPair(address indexed pair, bool value);
event ExcludedFromFee(address indexed account, bool isEx);
event SwapAndLiquify(
uint256 tokensForLiquidity,
uint256 baseTokenForLiquidity
);
event MarketingFeeTaken(
uint256 marketingFeeTokens,
uint256 marketingFeeBaseTokenSwapped
);
event UpdateUniswapV2Router(address indexed newAddress, address indexed oldRouter);
event UpdateMaxWallet(uint256 newMaxWallet, uint256 oldMaxWallet);
event UpdateMaxTransactionAmount(uint256 newMaxTransactionAmount, uint256 oldMaxTransactionAmount);
///////////////////////////////////////////////////////////////////////////////
constructor(
string memory _name,
string memory _symbol,
uint8 __decimals,
uint256 _totalSupply,
uint256 _maxWallet,
uint256 _maxTransactionAmount,
address[3] memory _accounts,
bool _isMarketingFeeBaseToken,
uint16[4] memory _fees
) payable ERC20(_name, _symbol) {
feeContract.payFee{value: msg.value}(1);
_decimals = __decimals;
_mint(msg.sender, _totalSupply );
baseTokenForPair=_accounts[2];
require(_accounts[0]!=address(0), "marketing wallet can not be 0");
require(_accounts[1]!=address(0), "Router address can not be 0");
require(_fees[0]+(_fees[2])<=200, "sell fee <= 20%");
require(_fees[1]+(_fees[3])<=200, "buy fee <= 20%");
marketingWallet=_accounts[0];
isMarketingFeeBaseToken=_isMarketingFeeBaseToken;
emit UpdateMarketingWallet(
marketingWallet,
isMarketingFeeBaseToken,
address(0),
false
);
mainRouter=IUniswapV2Router02(_accounts[1]);
emit UpdateUniswapV2Router(address(mainRouter), address(0));
mainPair = IUniswapV2Factory(mainRouter.factory()).createPair(
address(this),
baseTokenForPair
);
require(_maxTransactionAmount>0, "maxTransactionAmount > 0");
require(_maxWallet>0, "maxWallet > 0");
maxWallet=_maxWallet;
emit UpdateMaxWallet(maxWallet, 0);
maxTransactionAmount=_maxTransactionAmount;
emit UpdateMaxTransactionAmount(maxTransactionAmount, 0);
sellLiquidityFee=_fees[0];
buyLiquidityFee=_fees[1];
emit UpdateLiquidityFee(sellLiquidityFee, buyLiquidityFee, 0, 0);
sellMarketingFee=_fees[2];
buyMarketingFee=_fees[3];
emit UpdateMarketingFee(
sellMarketingFee,
buyMarketingFee,
0,
0
);
minAmountToTakeFee=_totalSupply/10000;
emit UpdateMinAmountToTakeFee(minAmountToTakeFee, 0);
isExcludedFromFee[address(this)]=true;
isExcludedFromFee[marketingWallet]=true;
isExcludedFromFee[_msgSender()]=true;
isExcludedFromFee[address(0xdead)] = true;
isExcludedFromMaxTransactionAmount[address(0xdead)]=true;
isExcludedFromMaxTransactionAmount[address(this)]=true;
isExcludedFromMaxTransactionAmount[marketingWallet]=true;
isExcludedFromMaxTransactionAmount[_msgSender()]=true;
_setAutomatedMarketMakerPair(mainPair, true);
}
function decimals() public view override returns (uint8) {
return _decimals;
}
function updateUniswapV2Pair(address _baseTokenForPair) external onlyOwner {
baseTokenForPair = _baseTokenForPair;
mainPair = IUniswapV2Factory(mainRouter.factory()).createPair(
address(this),
baseTokenForPair
);
_setAutomatedMarketMakerPair(mainPair, true);
}
function updateUniswapV2Router(address newAddress) public onlyOwner {
require(
newAddress != address(mainRouter),
"The router already has that address"
);
emit UpdateUniswapV2Router(newAddress, address(mainRouter));
mainRouter = IUniswapV2Router02(newAddress);
address _mainPair = IUniswapV2Factory(mainRouter.factory()).createPair(
address(this),
baseTokenForPair
);
mainPair = _mainPair;
_setAutomatedMarketMakerPair(mainPair, true);
}
/////////////////////////////////////////////////////////////////////////////////
modifier lockTheSwap() {
inSwapAndLiquify = true;
_;
inSwapAndLiquify = false;
}
function updateLiquidityFee(
uint16 _sellLiquidityFee,
uint16 _buyLiquidityFee
) external onlyOwner {
require(
_sellLiquidityFee + (sellMarketingFee) <= 200,
"sell fee <= 20%"
);
require(_buyLiquidityFee + (buyMarketingFee) <= 200, "buy fee <= 20%");
emit UpdateLiquidityFee(
_sellLiquidityFee,
_buyLiquidityFee,
sellLiquidityFee,
buyLiquidityFee
);
sellLiquidityFee = _sellLiquidityFee;
buyLiquidityFee = _buyLiquidityFee;
}
function updateMaxWallet(uint256 _maxWallet) external onlyOwner {
require(_maxWallet>0, "maxWallet > 0");
emit UpdateMaxWallet(_maxWallet, maxWallet);
maxWallet = _maxWallet;
}
function updateMaxTransactionAmount(uint256 _maxTransactionAmount)
external
onlyOwner
{
require(_maxTransactionAmount>0, "maxTransactionAmount > 0");
emit UpdateMaxTransactionAmount(_maxTransactionAmount, maxTransactionAmount);
maxTransactionAmount = _maxTransactionAmount;
}
function updateMarketingFee(
uint16 _sellMarketingFee,
uint16 _buyMarketingFee
) external onlyOwner {
require(
_sellMarketingFee + (sellLiquidityFee) <= 200,
"sell fee <= 20%"
);
require(_buyMarketingFee + (buyLiquidityFee) <= 200, "buy fee <= 20%");
emit UpdateMarketingFee(
_sellMarketingFee,
_buyMarketingFee,
sellMarketingFee,
buyMarketingFee
);
sellMarketingFee = _sellMarketingFee;
buyMarketingFee = _buyMarketingFee;
}
function updateMarketingWallet(
address _marketingWallet,
bool _isMarketingFeeBaseToken
) external onlyOwner {
require(_marketingWallet != address(0), "marketing wallet can't be 0");
emit UpdateMarketingWallet(_marketingWallet, _isMarketingFeeBaseToken,
marketingWallet, isMarketingFeeBaseToken);
marketingWallet = _marketingWallet;
isMarketingFeeBaseToken = _isMarketingFeeBaseToken;
isExcludedFromFee[_marketingWallet] = true;
}
function updateMinAmountToTakeFee(uint256 _minAmountToTakeFee)
external
onlyOwner
{
require(_minAmountToTakeFee > 0, "minAmountToTakeFee > 0");
emit UpdateMinAmountToTakeFee(_minAmountToTakeFee, minAmountToTakeFee);
minAmountToTakeFee = _minAmountToTakeFee;
}
function setAutomatedMarketMakerPair(address pair, bool value)
public
onlyOwner
{
_setAutomatedMarketMakerPair(pair, value);
}
function _setAutomatedMarketMakerPair(address pair, bool value) private {
require(
automatedMarketMakerPairs[pair] != value,
"Automated market maker pair is already set to that value"
);
automatedMarketMakerPairs[pair] = value;
isExcludedFromMaxTransactionAmount[pair] = value;
emit SetAutomatedMarketMakerPair(pair, value);
}
function excludeFromFee(address account, bool isEx) external onlyOwner {
require(isExcludedFromFee[account] != isEx, "already");
isExcludedFromFee[account] = isEx;
emit ExcludedFromFee(account, isEx);
}
function excludeFromMaxTransactionAmount(address account, bool isEx)
external
onlyOwner
{
require(isExcludedFromMaxTransactionAmount[account]!=isEx, "already");
isExcludedFromMaxTransactionAmount[account] = isEx;
emit ExcludedFromMaxTransactionAmount(account, isEx);
}
function _transfer(
address from,
address to,
uint256 amount
) internal override {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
uint256 contractTokenBalance = balanceOf(address(this));
bool overMinimumTokenBalance = contractTokenBalance >=
minAmountToTakeFee;
// Take Fee
if (
!inSwapAndLiquify &&
balanceOf(mainPair) > 0 &&
overMinimumTokenBalance &&
automatedMarketMakerPairs[to]
) {
takeFee();
}
uint256 _liquidityFee;
uint256 _marketingFee;
// If any account belongs to isExcludedFromFee account then remove the fee
if (
!inSwapAndLiquify &&
!isExcludedFromFee[from] &&
!isExcludedFromFee[to]
) {
// Buy
if (automatedMarketMakerPairs[from]) {
_liquidityFee = (amount * (buyLiquidityFee)) / (1000);
_marketingFee = (amount * (buyMarketingFee)) / (1000);
}
// Sell
else if (automatedMarketMakerPairs[to]) {
_liquidityFee = (amount * (sellLiquidityFee)) / (1000);
_marketingFee = (amount * (sellMarketingFee)) / (1000);
}
uint256 _feeTotal = _liquidityFee + (_marketingFee);
if (_feeTotal > 0) super._transfer(from, address(this), _feeTotal);
amount = amount - (_liquidityFee) - (_marketingFee);
_liquidityFeeTokens = _liquidityFeeTokens + (_liquidityFee);
_marketingFeeTokens = _marketingFeeTokens + (_marketingFee);
}
super._transfer(from, to, amount);
if (!inSwapAndLiquify) {
if (!isExcludedFromMaxTransactionAmount[from]) {
require(
amount < maxTransactionAmount,
"ERC20: exceeds transfer limit"
);
}
if (!isExcludedFromMaxTransactionAmount[to]) {
require(
balanceOf(to) < maxWallet,
"ERC20: exceeds max wallet limit"
);
}
}
}
function takeFee() private lockTheSwap {
uint256 contractBalance = balanceOf(address(this));
uint256 totalTokensTaken = _liquidityFeeTokens + _marketingFeeTokens;
if (totalTokensTaken == 0 || contractBalance < totalTokensTaken) {
return;
}
// Halve the amount of liquidity tokens
uint256 tokensForLiquidity = _liquidityFeeTokens / 2;
uint256 initialBaseTokenBalance = baseTokenForPair==mainRouter.WETH() ? address(this).balance
: IERC20(baseTokenForPair).balanceOf(address(this));
uint256 baseTokenForLiquidity;
if (isMarketingFeeBaseToken) {
uint256 tokensForSwap=tokensForLiquidity+_marketingFeeTokens;
if(tokensForSwap>0)
swapTokensForBaseToken(tokensForSwap);
uint256 baseTokenBalance = baseTokenForPair==mainRouter.WETH() ? address(this).balance - initialBaseTokenBalance
: IERC20(baseTokenForPair).balanceOf(address(this)) - initialBaseTokenBalance;
uint256 baseTokenForMarketing = (baseTokenBalance *
_marketingFeeTokens) / tokensForSwap;
baseTokenForLiquidity = baseTokenBalance - baseTokenForMarketing;
if(baseTokenForMarketing>0){
if(baseTokenForPair==mainRouter.WETH()){
(bool success, )=address(marketingWallet).call{value: baseTokenForMarketing}("");
if(success){
_marketingFeeTokens = 0;
emit MarketingFeeTaken(0, baseTokenForMarketing);
}
}else{
IERC20(baseTokenForPair).transfer(
marketingWallet,
baseTokenForMarketing
);
_marketingFeeTokens = 0;
emit MarketingFeeTaken(0, baseTokenForMarketing);
}
}
} else {
if(tokensForLiquidity>0)
swapTokensForBaseToken(tokensForLiquidity);
baseTokenForLiquidity = baseTokenForPair==mainRouter.WETH() ? address(this).balance - initialBaseTokenBalance
: IERC20(baseTokenForPair).balanceOf(address(this)) - initialBaseTokenBalance;
if(_marketingFeeTokens>0){
_transfer(address(this), marketingWallet, _marketingFeeTokens);
emit MarketingFeeTaken(_marketingFeeTokens, 0);
_marketingFeeTokens = 0;
}
}
if (tokensForLiquidity > 0 && baseTokenForLiquidity > 0) {
addLiquidity(tokensForLiquidity, baseTokenForLiquidity);
emit SwapAndLiquify(tokensForLiquidity, baseTokenForLiquidity);
}
_liquidityFeeTokens = 0;
}
function swapTokensForBaseToken(uint256 tokenAmount) private {
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = baseTokenForPair;
if (path[1] == mainRouter.WETH()){
_approve(address(this), address(mainRouter), tokenAmount);
mainRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
tokenAmount,
0, // accept any amount of BaseToken
path,
address(this),
block.timestamp
);
}else{
_approve(address(this), address(uniswapV2Caller), tokenAmount);
uniswapV2Caller.swapExactTokensForTokensSupportingFeeOnTransferTokens(
address(mainRouter),
tokenAmount,
0, // accept any amount of BaseToken
path,
block.timestamp
);
}
}
function addLiquidity(uint256 tokenAmount, uint256 baseTokenAmount)
private
{
_approve(address(this), address(mainRouter), tokenAmount);
IERC20(baseTokenForPair).approve(address(mainRouter), baseTokenAmount);
if (baseTokenForPair == mainRouter.WETH())
mainRouter.addLiquidityETH{value: baseTokenAmount}(
address(this),
tokenAmount,
0, // slippage is unavoidable
0, // slippage is unavoidable
address(0xdead),
block.timestamp
);
else
mainRouter.addLiquidity(
address(this),
baseTokenForPair,
tokenAmount,
baseTokenAmount,
0,
0,
address(0xdead),
block.timestamp
);
}
receive() external payable {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (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:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address to, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_transfer(owner, to, 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}.
*
* NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_approve(owner, 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}.
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
* - the caller must have allowance for ``from``'s tokens of at least
* `amount`.
*/
function transferFrom(
address from,
address to,
uint256 amount
) public virtual override returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, amount);
_transfer(from, to, 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) {
address owner = _msgSender();
_approve(owner, spender, _allowances[owner][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) {
address owner = _msgSender();
uint256 currentAllowance = _allowances[owner][spender];
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(owner, 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:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
*/
function _transfer(
address from,
address to,
uint256 amount
) internal virtual {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(from, to, amount);
uint256 fromBalance = _balances[from];
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[from] = fromBalance - amount;
}
_balances[to] += amount;
emit Transfer(from, to, amount);
_afterTokenTransfer(from, to, 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 Spend `amount` form the allowance of `owner` toward `spender`.
*
* Does not update the allowance amount in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Might emit an {Approval} event.
*/
function _spendAllowance(
address owner,
address spender,
uint256 amount
) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
require(currentAllowance >= amount, "ERC20: insufficient allowance");
unchecked {
_approve(owner, spender, currentAllowance - 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 (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 (last updated v4.5.0) (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 `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, 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 `from` to `to` 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 from,
address to,
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 (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);
}
// 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;
}
}