파일 1 / 1 : VirusToken.sol
pragma solidity ^0.8.9;
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
}
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
constructor() {
_transferOwnership(_msgSender());
}
modifier onlyOwner() {
_checkOwner();
_;
}
function owner() public view virtual returns (address) {
return _owner;
}
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
interface IERC20 {
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address to, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
interface IERC20Metadata is IERC20 {
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view returns (uint8);
}
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;
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
function name() public view virtual override returns (string memory) {
return _name;
}
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
function decimals() public view virtual override returns (uint8) {
return 18;
}
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
function balanceOf(address account) public view virtual override returns (uint256) {
return _balances[account];
}
function transfer(address to, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_transfer(owner, to, amount);
return true;
}
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
function approve(address spender, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_approve(owner, spender, amount);
return true;
}
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;
}
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");
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);
}
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply += amount;
unchecked {
_balances[account] += amount;
}
emit Transfer(address(0), account, amount);
}
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);
}
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);
}
}
}
}
interface IUniswapV2Factory {
function createPair(address tokenA, address tokenB) external returns (address pair);
}
interface IUniswapV2Router02 {
function factory() external pure returns (address);
function WETH() external pure returns (address);
}
contract VirusToken is ERC20, Ownable {
IUniswapV2Router02 public immutable uniswapV2Router;
address public immutable uniswapV2Pair;
address public constant deadAddress = address(0xdead);
bool public limitsInEffect = true;
uint256 public maxTransactionAmount;
mapping(address => bool) private excludedMaxTransactionAmount;
constructor() ERC20("Virus Token", "VIRUS") {
IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
uniswapV2Router = _uniswapV2Router;
uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), _uniswapV2Router.WETH());
uint256 totalSupply = 1000000000 * 10**decimals();
maxTransactionAmount = totalSupply * 2 / 100;
excludedMaxTransactionAmount[address(_uniswapV2Router)] = true;
excludedMaxTransactionAmount[address(uniswapV2Pair)] = true;
excludedMaxTransactionAmount[owner()] = true;
excludedMaxTransactionAmount[address(this)] = true;
_mint(_msgSender(), totalSupply);
}
receive() external payable {}
function removeLimits() external onlyOwner {
require(limitsInEffect == true, "The limits has been removed.");
limitsInEffect = false;
}
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.");
require(amount > 0, "ERC20: transfer amount must be greater than zero.");
if (limitsInEffect == true && from != owner() && to != owner() && to != address(0) && to != address(0xdead)) {
if (uniswapV2Pair == from && !excludedMaxTransactionAmount[to]) {
require(amount <= maxTransactionAmount, "ERC20: Buy transfer amount exceeds the max transaction amount.");
} else if (uniswapV2Pair == to && !excludedMaxTransactionAmount[from]) {
require(amount <= maxTransactionAmount, "ERC20: Sell transfer amount exceeds the max transaction amount.");
}
}
super._transfer(from, to, amount);
}
}