Transaction Hash:
Block:
11025671 at Oct-10-2020 04:57:40 AM +UTC
Transaction Fee:
0.00259408 ETH
$5.31
Gas Used:
41,840 Gas / 62 Gwei
Account State Difference:
| Address | Before | After | State Difference | ||
|---|---|---|---|---|---|
|
0x5A0b54D5...D3E029c4c
Miner
| (Spark Pool) | 79.591588381060032829 Eth | 79.594182461060032829 Eth | 0.00259408 | |
| 0xcAb9F75E...e43f790BC |
0.339126982974849637 Eth
Nonce: 99
|
0.336532902974849637 Eth
Nonce: 100
| 0.00259408 |
Execution Trace
UniswapV2Router02.addLiquidity( tokenA=0x05D3606d5c81EB9b7B18530995eC9B29da05FaBa, tokenB=0xB1f66997A5760428D3a87D68b90BfE0aE64121cC, amountADesired=16821782024855384329, amountBDesired=70575797346835777342, amountAMin=16737673114731107407, amountBMin=70222918360101598455, to=0xcAb9F75ECc5759976fa11acb8F77b83e43f790BC, deadline=1602306994 ) => ( amountA=3963877391197344453575983046348115674221700746820753546331534351508065746944, amountB=862718293348820473429344482784628181556388621521298319395315527974912, liquidity=979451365963766574087307771853635596334973034459934101565131045884495 )
-
UniswapV2Factory.getPair( 0x05D3606d5c81EB9b7B18530995eC9B29da05FaBa, 0xB1f66997A5760428D3a87D68b90BfE0aE64121cC ) => ( 0x9Ccc3e17ae1d1438bACdE4D906cDc56Bb6937E46 ) -
UniswapV2Pair.STATICCALL( )
-
TomoE.transferFrom( from=0xcAb9F75ECc5759976fa11acb8F77b83e43f790BC, to=0x9Ccc3e17ae1d1438bACdE4D906cDc56Bb6937E46, value=16821782024855384329 )
addLiquidity[UniswapV2Router02 (ln:276)]
_addLiquidity[UniswapV2Router02 (ln:286)]getPair[UniswapV2Router02 (ln:257)]createPair[UniswapV2Router02 (ln:258)]getReserves[UniswapV2Router02 (ln:260)]sortTokens[UniswapV2Library (ln:702)]getReserves[UniswapV2Library (ln:703)]pairFor[UniswapV2Library (ln:703)]sortTokens[UniswapV2Library (ln:691)]
pairFor[UniswapV2Router02 (ln:287)]sortTokens[UniswapV2Library (ln:691)]
safeTransferFrom[UniswapV2Router02 (ln:288)]call[TransferHelper (ln:772)]encodeWithSelector[TransferHelper (ln:772)]decode[TransferHelper (ln:773)]
safeTransferFrom[UniswapV2Router02 (ln:289)]call[TransferHelper (ln:772)]encodeWithSelector[TransferHelper (ln:772)]decode[TransferHelper (ln:773)]
mint[UniswapV2Router02 (ln:290)]
File 1 of 4: UniswapV2Router02
File 2 of 4: UniswapV2Factory
File 3 of 4: UniswapV2Pair
File 4 of 4: TomoE
pragma solidity =0.6.6;
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
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(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
}
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;
}
interface IUniswapV2Router01 {
function factory() external pure returns (address);
function WETH() external pure returns (address);
function addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB, uint liquidity);
function addLiquidityETH(
address token,
uint amountTokenDesired,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external payable returns (uint amountToken, uint amountETH, uint liquidity);
function removeLiquidity(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB);
function removeLiquidityETH(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountToken, uint amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountA, uint amountB);
function removeLiquidityETHWithPermit(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountToken, uint amountETH);
function swapExactTokensForTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapTokensForExactTokens(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}
interface IUniswapV2Router02 is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
}
interface IERC20 {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view 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);
}
interface IWETH {
function deposit() external payable;
function transfer(address to, uint value) external returns (bool);
function withdraw(uint) external;
}
contract UniswapV2Router02 is IUniswapV2Router02 {
using SafeMath for uint;
address public immutable override factory;
address public immutable override WETH;
modifier ensure(uint deadline) {
require(deadline >= block.timestamp, 'UniswapV2Router: EXPIRED');
_;
}
constructor(address _factory, address _WETH) public {
factory = _factory;
WETH = _WETH;
}
receive() external payable {
assert(msg.sender == WETH); // only accept ETH via fallback from the WETH contract
}
// **** ADD LIQUIDITY ****
function _addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin
) internal virtual returns (uint amountA, uint amountB) {
// create the pair if it doesn't exist yet
if (IUniswapV2Factory(factory).getPair(tokenA, tokenB) == address(0)) {
IUniswapV2Factory(factory).createPair(tokenA, tokenB);
}
(uint reserveA, uint reserveB) = UniswapV2Library.getReserves(factory, tokenA, tokenB);
if (reserveA == 0 && reserveB == 0) {
(amountA, amountB) = (amountADesired, amountBDesired);
} else {
uint amountBOptimal = UniswapV2Library.quote(amountADesired, reserveA, reserveB);
if (amountBOptimal <= amountBDesired) {
require(amountBOptimal >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
(amountA, amountB) = (amountADesired, amountBOptimal);
} else {
uint amountAOptimal = UniswapV2Library.quote(amountBDesired, reserveB, reserveA);
assert(amountAOptimal <= amountADesired);
require(amountAOptimal >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
(amountA, amountB) = (amountAOptimal, amountBDesired);
}
}
}
function addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external virtual override ensure(deadline) returns (uint amountA, uint amountB, uint liquidity) {
(amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA);
TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB);
liquidity = IUniswapV2Pair(pair).mint(to);
}
function addLiquidityETH(
address token,
uint amountTokenDesired,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external virtual override payable ensure(deadline) returns (uint amountToken, uint amountETH, uint liquidity) {
(amountToken, amountETH) = _addLiquidity(
token,
WETH,
amountTokenDesired,
msg.value,
amountTokenMin,
amountETHMin
);
address pair = UniswapV2Library.pairFor(factory, token, WETH);
TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken);
IWETH(WETH).deposit{value: amountETH}();
assert(IWETH(WETH).transfer(pair, amountETH));
liquidity = IUniswapV2Pair(pair).mint(to);
// refund dust eth, if any
if (msg.value > amountETH) TransferHelper.safeTransferETH(msg.sender, msg.value - amountETH);
}
// **** REMOVE LIQUIDITY ****
function removeLiquidity(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) public virtual override ensure(deadline) returns (uint amountA, uint amountB) {
address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
(uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(to);
(address token0,) = UniswapV2Library.sortTokens(tokenA, tokenB);
(amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
require(amountA >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
require(amountB >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
}
function removeLiquidityETH(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) public virtual override ensure(deadline) returns (uint amountToken, uint amountETH) {
(amountToken, amountETH) = removeLiquidity(
token,
WETH,
liquidity,
amountTokenMin,
amountETHMin,
address(this),
deadline
);
TransferHelper.safeTransfer(token, to, amountToken);
IWETH(WETH).withdraw(amountETH);
TransferHelper.safeTransferETH(to, amountETH);
}
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external virtual override returns (uint amountA, uint amountB) {
address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
uint value = approveMax ? uint(-1) : liquidity;
IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
(amountA, amountB) = removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline);
}
function removeLiquidityETHWithPermit(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external virtual override returns (uint amountToken, uint amountETH) {
address pair = UniswapV2Library.pairFor(factory, token, WETH);
uint value = approveMax ? uint(-1) : liquidity;
IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
(amountToken, amountETH) = removeLiquidityETH(token, liquidity, amountTokenMin, amountETHMin, to, deadline);
}
// **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens) ****
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) public virtual override ensure(deadline) returns (uint amountETH) {
(, amountETH) = removeLiquidity(
token,
WETH,
liquidity,
amountTokenMin,
amountETHMin,
address(this),
deadline
);
TransferHelper.safeTransfer(token, to, IERC20(token).balanceOf(address(this)));
IWETH(WETH).withdraw(amountETH);
TransferHelper.safeTransferETH(to, amountETH);
}
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external virtual override returns (uint amountETH) {
address pair = UniswapV2Library.pairFor(factory, token, WETH);
uint value = approveMax ? uint(-1) : liquidity;
IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
amountETH = removeLiquidityETHSupportingFeeOnTransferTokens(
token, liquidity, amountTokenMin, amountETHMin, to, deadline
);
}
// **** SWAP ****
// requires the initial amount to have already been sent to the first pair
function _swap(uint[] memory amounts, address[] memory path, address _to) internal virtual {
for (uint i; i < path.length - 1; i++) {
(address input, address output) = (path[i], path[i + 1]);
(address token0,) = UniswapV2Library.sortTokens(input, output);
uint amountOut = amounts[i + 1];
(uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOut) : (amountOut, uint(0));
address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)).swap(
amount0Out, amount1Out, to, new bytes(0)
);
}
}
function swapExactTokensForTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external virtual override ensure(deadline) returns (uint[] memory amounts) {
amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
TransferHelper.safeTransferFrom(
path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
);
_swap(amounts, path, to);
}
function swapTokensForExactTokens(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline
) external virtual override ensure(deadline) returns (uint[] memory amounts) {
amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
TransferHelper.safeTransferFrom(
path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
);
_swap(amounts, path, to);
}
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
external
virtual
override
payable
ensure(deadline)
returns (uint[] memory amounts)
{
require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
amounts = UniswapV2Library.getAmountsOut(factory, msg.value, path);
require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
IWETH(WETH).deposit{value: amounts[0]}();
assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
_swap(amounts, path, to);
}
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
external
virtual
override
ensure(deadline)
returns (uint[] memory amounts)
{
require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
TransferHelper.safeTransferFrom(
path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
);
_swap(amounts, path, address(this));
IWETH(WETH).withdraw(amounts[amounts.length - 1]);
TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
}
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
external
virtual
override
ensure(deadline)
returns (uint[] memory amounts)
{
require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
TransferHelper.safeTransferFrom(
path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
);
_swap(amounts, path, address(this));
IWETH(WETH).withdraw(amounts[amounts.length - 1]);
TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
}
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
external
virtual
override
payable
ensure(deadline)
returns (uint[] memory amounts)
{
require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
require(amounts[0] <= msg.value, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
IWETH(WETH).deposit{value: amounts[0]}();
assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
_swap(amounts, path, to);
// refund dust eth, if any
if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]);
}
// **** SWAP (supporting fee-on-transfer tokens) ****
// requires the initial amount to have already been sent to the first pair
function _swapSupportingFeeOnTransferTokens(address[] memory path, address _to) internal virtual {
for (uint i; i < path.length - 1; i++) {
(address input, address output) = (path[i], path[i + 1]);
(address token0,) = UniswapV2Library.sortTokens(input, output);
IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output));
uint amountInput;
uint amountOutput;
{ // scope to avoid stack too deep errors
(uint reserve0, uint reserve1,) = pair.getReserves();
(uint reserveInput, uint reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
}
(uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOutput) : (amountOutput, uint(0));
address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
pair.swap(amount0Out, amount1Out, to, new bytes(0));
}
}
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external virtual override ensure(deadline) {
TransferHelper.safeTransferFrom(
path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
);
uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
_swapSupportingFeeOnTransferTokens(path, to);
require(
IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
);
}
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
)
external
virtual
override
payable
ensure(deadline)
{
require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
uint amountIn = msg.value;
IWETH(WETH).deposit{value: amountIn}();
assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn));
uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
_swapSupportingFeeOnTransferTokens(path, to);
require(
IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
);
}
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
)
external
virtual
override
ensure(deadline)
{
require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
TransferHelper.safeTransferFrom(
path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
);
_swapSupportingFeeOnTransferTokens(path, address(this));
uint amountOut = IERC20(WETH).balanceOf(address(this));
require(amountOut >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
IWETH(WETH).withdraw(amountOut);
TransferHelper.safeTransferETH(to, amountOut);
}
// **** LIBRARY FUNCTIONS ****
function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) {
return UniswapV2Library.quote(amountA, reserveA, reserveB);
}
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut)
public
pure
virtual
override
returns (uint amountOut)
{
return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
}
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut)
public
pure
virtual
override
returns (uint amountIn)
{
return UniswapV2Library.getAmountIn(amountOut, reserveIn, reserveOut);
}
function getAmountsOut(uint amountIn, address[] memory path)
public
view
virtual
override
returns (uint[] memory amounts)
{
return UniswapV2Library.getAmountsOut(factory, amountIn, path);
}
function getAmountsIn(uint amountOut, address[] memory path)
public
view
virtual
override
returns (uint[] memory amounts)
{
return UniswapV2Library.getAmountsIn(factory, amountOut, path);
}
}
// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
library SafeMath {
function add(uint x, uint y) internal pure returns (uint z) {
require((z = x + y) >= x, 'ds-math-add-overflow');
}
function sub(uint x, uint y) internal pure returns (uint z) {
require((z = x - y) <= x, 'ds-math-sub-underflow');
}
function mul(uint x, uint y) internal pure returns (uint z) {
require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
}
}
library UniswapV2Library {
using SafeMath for uint;
// returns sorted token addresses, used to handle return values from pairs sorted in this order
function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
(token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
}
// calculates the CREATE2 address for a pair without making any external calls
function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
(address token0, address token1) = sortTokens(tokenA, tokenB);
pair = address(uint(keccak256(abi.encodePacked(
hex'ff',
factory,
keccak256(abi.encodePacked(token0, token1)),
hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
))));
}
// fetches and sorts the reserves for a pair
function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) {
(address token0,) = sortTokens(tokenA, tokenB);
(uint reserve0, uint reserve1,) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
(reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
}
// given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) {
require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
amountB = amountA.mul(reserveB) / reserveA;
}
// given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) {
require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
uint amountInWithFee = amountIn.mul(997);
uint numerator = amountInWithFee.mul(reserveOut);
uint denominator = reserveIn.mul(1000).add(amountInWithFee);
amountOut = numerator / denominator;
}
// given an output amount of an asset and pair reserves, returns a required input amount of the other asset
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) {
require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
uint numerator = reserveIn.mul(amountOut).mul(1000);
uint denominator = reserveOut.sub(amountOut).mul(997);
amountIn = (numerator / denominator).add(1);
}
// performs chained getAmountOut calculations on any number of pairs
function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) {
require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
amounts = new uint[](path.length);
amounts[0] = amountIn;
for (uint i; i < path.length - 1; i++) {
(uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]);
amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
}
}
// performs chained getAmountIn calculations on any number of pairs
function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) {
require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
amounts = new uint[](path.length);
amounts[amounts.length - 1] = amountOut;
for (uint i = path.length - 1; i > 0; i--) {
(uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]);
amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
}
}
}
// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
function safeApprove(address token, address to, uint value) internal {
// bytes4(keccak256(bytes('approve(address,uint256)')));
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
}
function safeTransfer(address token, address to, uint value) internal {
// bytes4(keccak256(bytes('transfer(address,uint256)')));
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FAILED');
}
function safeTransferFrom(address token, address from, address to, uint value) internal {
// bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FROM_FAILED');
}
function safeTransferETH(address to, uint value) internal {
(bool success,) = to.call{value:value}(new bytes(0));
require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
}
}File 2 of 4: UniswapV2Factory
pragma solidity =0.5.16;
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
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(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
}
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;
}
interface IUniswapV2ERC20 {
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;
}
interface IERC20 {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view 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);
}
interface IUniswapV2Callee {
function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
}
contract UniswapV2ERC20 is IUniswapV2ERC20 {
using SafeMath for uint;
string public constant name = 'Uniswap V2';
string public constant symbol = 'UNI-V2';
uint8 public constant decimals = 18;
uint public totalSupply;
mapping(address => uint) public balanceOf;
mapping(address => mapping(address => uint)) public allowance;
bytes32 public DOMAIN_SEPARATOR;
// keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
mapping(address => uint) public nonces;
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
constructor() public {
uint chainId;
assembly {
chainId := chainid
}
DOMAIN_SEPARATOR = keccak256(
abi.encode(
keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
keccak256(bytes(name)),
keccak256(bytes('1')),
chainId,
address(this)
)
);
}
function _mint(address to, uint value) internal {
totalSupply = totalSupply.add(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(address(0), to, value);
}
function _burn(address from, uint value) internal {
balanceOf[from] = balanceOf[from].sub(value);
totalSupply = totalSupply.sub(value);
emit Transfer(from, address(0), value);
}
function _approve(address owner, address spender, uint value) private {
allowance[owner][spender] = value;
emit Approval(owner, spender, value);
}
function _transfer(address from, address to, uint value) private {
balanceOf[from] = balanceOf[from].sub(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(from, to, value);
}
function approve(address spender, uint value) external returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
function transfer(address to, uint value) external returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
function transferFrom(address from, address to, uint value) external returns (bool) {
if (allowance[from][msg.sender] != uint(-1)) {
allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
}
_transfer(from, to, value);
return true;
}
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
bytes32 digest = keccak256(
abi.encodePacked(
'\x19\x01',
DOMAIN_SEPARATOR,
keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
)
);
address recoveredAddress = ecrecover(digest, v, r, s);
require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
_approve(owner, spender, value);
}
}
contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
using SafeMath for uint;
using UQ112x112 for uint224;
uint public constant MINIMUM_LIQUIDITY = 10**3;
bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));
address public factory;
address public token0;
address public token1;
uint112 private reserve0; // uses single storage slot, accessible via getReserves
uint112 private reserve1; // uses single storage slot, accessible via getReserves
uint32 private blockTimestampLast; // uses single storage slot, accessible via getReserves
uint public price0CumulativeLast;
uint public price1CumulativeLast;
uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event
uint private unlocked = 1;
modifier lock() {
require(unlocked == 1, 'UniswapV2: LOCKED');
unlocked = 0;
_;
unlocked = 1;
}
function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
_reserve0 = reserve0;
_reserve1 = reserve1;
_blockTimestampLast = blockTimestampLast;
}
function _safeTransfer(address token, address to, uint value) private {
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
}
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);
constructor() public {
factory = msg.sender;
}
// called once by the factory at time of deployment
function initialize(address _token0, address _token1) external {
require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
token0 = _token0;
token1 = _token1;
}
// update reserves and, on the first call per block, price accumulators
function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
uint32 blockTimestamp = uint32(block.timestamp % 2**32);
uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
// * never overflows, and + overflow is desired
price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
}
reserve0 = uint112(balance0);
reserve1 = uint112(balance1);
blockTimestampLast = blockTimestamp;
emit Sync(reserve0, reserve1);
}
// if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
address feeTo = IUniswapV2Factory(factory).feeTo();
feeOn = feeTo != address(0);
uint _kLast = kLast; // gas savings
if (feeOn) {
if (_kLast != 0) {
uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
uint rootKLast = Math.sqrt(_kLast);
if (rootK > rootKLast) {
uint numerator = totalSupply.mul(rootK.sub(rootKLast));
uint denominator = rootK.mul(5).add(rootKLast);
uint liquidity = numerator / denominator;
if (liquidity > 0) _mint(feeTo, liquidity);
}
}
} else if (_kLast != 0) {
kLast = 0;
}
}
// this low-level function should be called from a contract which performs important safety checks
function mint(address to) external lock returns (uint liquidity) {
(uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
uint balance0 = IERC20(token0).balanceOf(address(this));
uint balance1 = IERC20(token1).balanceOf(address(this));
uint amount0 = balance0.sub(_reserve0);
uint amount1 = balance1.sub(_reserve1);
bool feeOn = _mintFee(_reserve0, _reserve1);
uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
if (_totalSupply == 0) {
liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
_mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
} else {
liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
}
require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
_mint(to, liquidity);
_update(balance0, balance1, _reserve0, _reserve1);
if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
emit Mint(msg.sender, amount0, amount1);
}
// this low-level function should be called from a contract which performs important safety checks
function burn(address to) external lock returns (uint amount0, uint amount1) {
(uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
address _token0 = token0; // gas savings
address _token1 = token1; // gas savings
uint balance0 = IERC20(_token0).balanceOf(address(this));
uint balance1 = IERC20(_token1).balanceOf(address(this));
uint liquidity = balanceOf[address(this)];
bool feeOn = _mintFee(_reserve0, _reserve1);
uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
_burn(address(this), liquidity);
_safeTransfer(_token0, to, amount0);
_safeTransfer(_token1, to, amount1);
balance0 = IERC20(_token0).balanceOf(address(this));
balance1 = IERC20(_token1).balanceOf(address(this));
_update(balance0, balance1, _reserve0, _reserve1);
if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
emit Burn(msg.sender, amount0, amount1, to);
}
// this low-level function should be called from a contract which performs important safety checks
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
(uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');
uint balance0;
uint balance1;
{ // scope for _token{0,1}, avoids stack too deep errors
address _token0 = token0;
address _token1 = token1;
require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
balance0 = IERC20(_token0).balanceOf(address(this));
balance1 = IERC20(_token1).balanceOf(address(this));
}
uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
{ // scope for reserve{0,1}Adjusted, avoids stack too deep errors
uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
}
_update(balance0, balance1, _reserve0, _reserve1);
emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
}
// force balances to match reserves
function skim(address to) external lock {
address _token0 = token0; // gas savings
address _token1 = token1; // gas savings
_safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
_safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
}
// force reserves to match balances
function sync() external lock {
_update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
}
}
contract UniswapV2Factory is IUniswapV2Factory {
address public feeTo;
address public feeToSetter;
mapping(address => mapping(address => address)) public getPair;
address[] public allPairs;
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
constructor(address _feeToSetter) public {
feeToSetter = _feeToSetter;
}
function allPairsLength() external view returns (uint) {
return allPairs.length;
}
function createPair(address tokenA, address tokenB) external returns (address pair) {
require(tokenA != tokenB, 'UniswapV2: IDENTICAL_ADDRESSES');
(address token0, address token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
require(token0 != address(0), 'UniswapV2: ZERO_ADDRESS');
require(getPair[token0][token1] == address(0), 'UniswapV2: PAIR_EXISTS'); // single check is sufficient
bytes memory bytecode = type(UniswapV2Pair).creationCode;
bytes32 salt = keccak256(abi.encodePacked(token0, token1));
assembly {
pair := create2(0, add(bytecode, 32), mload(bytecode), salt)
}
IUniswapV2Pair(pair).initialize(token0, token1);
getPair[token0][token1] = pair;
getPair[token1][token0] = pair; // populate mapping in the reverse direction
allPairs.push(pair);
emit PairCreated(token0, token1, pair, allPairs.length);
}
function setFeeTo(address _feeTo) external {
require(msg.sender == feeToSetter, 'UniswapV2: FORBIDDEN');
feeTo = _feeTo;
}
function setFeeToSetter(address _feeToSetter) external {
require(msg.sender == feeToSetter, 'UniswapV2: FORBIDDEN');
feeToSetter = _feeToSetter;
}
}
// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
library SafeMath {
function add(uint x, uint y) internal pure returns (uint z) {
require((z = x + y) >= x, 'ds-math-add-overflow');
}
function sub(uint x, uint y) internal pure returns (uint z) {
require((z = x - y) <= x, 'ds-math-sub-underflow');
}
function mul(uint x, uint y) internal pure returns (uint z) {
require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
}
}
// a library for performing various math operations
library Math {
function min(uint x, uint y) internal pure returns (uint z) {
z = x < y ? x : y;
}
// babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
function sqrt(uint y) internal pure returns (uint z) {
if (y > 3) {
z = y;
uint x = y / 2 + 1;
while (x < z) {
z = x;
x = (y / x + x) / 2;
}
} else if (y != 0) {
z = 1;
}
}
}
// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
// range: [0, 2**112 - 1]
// resolution: 1 / 2**112
library UQ112x112 {
uint224 constant Q112 = 2**112;
// encode a uint112 as a UQ112x112
function encode(uint112 y) internal pure returns (uint224 z) {
z = uint224(y) * Q112; // never overflows
}
// divide a UQ112x112 by a uint112, returning a UQ112x112
function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
z = x / uint224(y);
}
}File 3 of 4: UniswapV2Pair
// File: contracts/interfaces/IUniswapV2Pair.sol
pragma solidity >=0.5.0;
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;
}
// File: contracts/interfaces/IUniswapV2ERC20.sol
pragma solidity >=0.5.0;
interface IUniswapV2ERC20 {
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;
}
// File: contracts/libraries/SafeMath.sol
pragma solidity =0.5.16;
// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
library SafeMath {
function add(uint x, uint y) internal pure returns (uint z) {
require((z = x + y) >= x, 'ds-math-add-overflow');
}
function sub(uint x, uint y) internal pure returns (uint z) {
require((z = x - y) <= x, 'ds-math-sub-underflow');
}
function mul(uint x, uint y) internal pure returns (uint z) {
require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
}
}
// File: contracts/UniswapV2ERC20.sol
pragma solidity =0.5.16;
contract UniswapV2ERC20 is IUniswapV2ERC20 {
using SafeMath for uint;
string public constant name = 'Uniswap V2';
string public constant symbol = 'UNI-V2';
uint8 public constant decimals = 18;
uint public totalSupply;
mapping(address => uint) public balanceOf;
mapping(address => mapping(address => uint)) public allowance;
bytes32 public DOMAIN_SEPARATOR;
// keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
mapping(address => uint) public nonces;
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
constructor() public {
uint chainId;
assembly {
chainId := chainid
}
DOMAIN_SEPARATOR = keccak256(
abi.encode(
keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
keccak256(bytes(name)),
keccak256(bytes('1')),
chainId,
address(this)
)
);
}
function _mint(address to, uint value) internal {
totalSupply = totalSupply.add(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(address(0), to, value);
}
function _burn(address from, uint value) internal {
balanceOf[from] = balanceOf[from].sub(value);
totalSupply = totalSupply.sub(value);
emit Transfer(from, address(0), value);
}
function _approve(address owner, address spender, uint value) private {
allowance[owner][spender] = value;
emit Approval(owner, spender, value);
}
function _transfer(address from, address to, uint value) private {
balanceOf[from] = balanceOf[from].sub(value);
balanceOf[to] = balanceOf[to].add(value);
emit Transfer(from, to, value);
}
function approve(address spender, uint value) external returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
function transfer(address to, uint value) external returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
function transferFrom(address from, address to, uint value) external returns (bool) {
if (allowance[from][msg.sender] != uint(-1)) {
allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
}
_transfer(from, to, value);
return true;
}
function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
bytes32 digest = keccak256(
abi.encodePacked(
'\x19\x01',
DOMAIN_SEPARATOR,
keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
)
);
address recoveredAddress = ecrecover(digest, v, r, s);
require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
_approve(owner, spender, value);
}
}
// File: contracts/libraries/Math.sol
pragma solidity =0.5.16;
// a library for performing various math operations
library Math {
function min(uint x, uint y) internal pure returns (uint z) {
z = x < y ? x : y;
}
// babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
function sqrt(uint y) internal pure returns (uint z) {
if (y > 3) {
z = y;
uint x = y / 2 + 1;
while (x < z) {
z = x;
x = (y / x + x) / 2;
}
} else if (y != 0) {
z = 1;
}
}
}
// File: contracts/libraries/UQ112x112.sol
pragma solidity =0.5.16;
// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
// range: [0, 2**112 - 1]
// resolution: 1 / 2**112
library UQ112x112 {
uint224 constant Q112 = 2**112;
// encode a uint112 as a UQ112x112
function encode(uint112 y) internal pure returns (uint224 z) {
z = uint224(y) * Q112; // never overflows
}
// divide a UQ112x112 by a uint112, returning a UQ112x112
function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
z = x / uint224(y);
}
}
// File: contracts/interfaces/IERC20.sol
pragma solidity >=0.5.0;
interface IERC20 {
event Approval(address indexed owner, address indexed spender, uint value);
event Transfer(address indexed from, address indexed to, uint value);
function name() external view returns (string memory);
function symbol() external view returns (string memory);
function decimals() external view 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);
}
// File: contracts/interfaces/IUniswapV2Factory.sol
pragma solidity >=0.5.0;
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
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(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
}
// File: contracts/interfaces/IUniswapV2Callee.sol
pragma solidity >=0.5.0;
interface IUniswapV2Callee {
function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
}
// File: contracts/UniswapV2Pair.sol
pragma solidity =0.5.16;
contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
using SafeMath for uint;
using UQ112x112 for uint224;
uint public constant MINIMUM_LIQUIDITY = 10**3;
bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));
address public factory;
address public token0;
address public token1;
uint112 private reserve0; // uses single storage slot, accessible via getReserves
uint112 private reserve1; // uses single storage slot, accessible via getReserves
uint32 private blockTimestampLast; // uses single storage slot, accessible via getReserves
uint public price0CumulativeLast;
uint public price1CumulativeLast;
uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event
uint private unlocked = 1;
modifier lock() {
require(unlocked == 1, 'UniswapV2: LOCKED');
unlocked = 0;
_;
unlocked = 1;
}
function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
_reserve0 = reserve0;
_reserve1 = reserve1;
_blockTimestampLast = blockTimestampLast;
}
function _safeTransfer(address token, address to, uint value) private {
(bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
}
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);
constructor() public {
factory = msg.sender;
}
// called once by the factory at time of deployment
function initialize(address _token0, address _token1) external {
require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
token0 = _token0;
token1 = _token1;
}
// update reserves and, on the first call per block, price accumulators
function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
uint32 blockTimestamp = uint32(block.timestamp % 2**32);
uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
// * never overflows, and + overflow is desired
price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
}
reserve0 = uint112(balance0);
reserve1 = uint112(balance1);
blockTimestampLast = blockTimestamp;
emit Sync(reserve0, reserve1);
}
// if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
address feeTo = IUniswapV2Factory(factory).feeTo();
feeOn = feeTo != address(0);
uint _kLast = kLast; // gas savings
if (feeOn) {
if (_kLast != 0) {
uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
uint rootKLast = Math.sqrt(_kLast);
if (rootK > rootKLast) {
uint numerator = totalSupply.mul(rootK.sub(rootKLast));
uint denominator = rootK.mul(5).add(rootKLast);
uint liquidity = numerator / denominator;
if (liquidity > 0) _mint(feeTo, liquidity);
}
}
} else if (_kLast != 0) {
kLast = 0;
}
}
// this low-level function should be called from a contract which performs important safety checks
function mint(address to) external lock returns (uint liquidity) {
(uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
uint balance0 = IERC20(token0).balanceOf(address(this));
uint balance1 = IERC20(token1).balanceOf(address(this));
uint amount0 = balance0.sub(_reserve0);
uint amount1 = balance1.sub(_reserve1);
bool feeOn = _mintFee(_reserve0, _reserve1);
uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
if (_totalSupply == 0) {
liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
_mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
} else {
liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
}
require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
_mint(to, liquidity);
_update(balance0, balance1, _reserve0, _reserve1);
if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
emit Mint(msg.sender, amount0, amount1);
}
// this low-level function should be called from a contract which performs important safety checks
function burn(address to) external lock returns (uint amount0, uint amount1) {
(uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
address _token0 = token0; // gas savings
address _token1 = token1; // gas savings
uint balance0 = IERC20(_token0).balanceOf(address(this));
uint balance1 = IERC20(_token1).balanceOf(address(this));
uint liquidity = balanceOf[address(this)];
bool feeOn = _mintFee(_reserve0, _reserve1);
uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
_burn(address(this), liquidity);
_safeTransfer(_token0, to, amount0);
_safeTransfer(_token1, to, amount1);
balance0 = IERC20(_token0).balanceOf(address(this));
balance1 = IERC20(_token1).balanceOf(address(this));
_update(balance0, balance1, _reserve0, _reserve1);
if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
emit Burn(msg.sender, amount0, amount1, to);
}
// this low-level function should be called from a contract which performs important safety checks
function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
(uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');
uint balance0;
uint balance1;
{ // scope for _token{0,1}, avoids stack too deep errors
address _token0 = token0;
address _token1 = token1;
require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
balance0 = IERC20(_token0).balanceOf(address(this));
balance1 = IERC20(_token1).balanceOf(address(this));
}
uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
{ // scope for reserve{0,1}Adjusted, avoids stack too deep errors
uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
}
_update(balance0, balance1, _reserve0, _reserve1);
emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
}
// force balances to match reserves
function skim(address to) external lock {
address _token0 = token0; // gas savings
address _token1 = token1; // gas savings
_safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
_safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
}
// force reserves to match balances
function sync() external lock {
_update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
}
}File 4 of 4: TomoE
pragma solidity ^0.4.24;
/**
* @title SafeMath
* @dev Math operations with safety checks that revert on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, reverts on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// 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-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0); // Solidity only automatically asserts when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a);
uint256 c = a - b;
return c;
}
/**
* @dev Adds two numbers, reverts on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
/**
* @dev Divides two numbers and returns the remainder (unsigned integer modulo),
* reverts when dividing by zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0);
return a % b;
}
}
contract ERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowed;
uint256 private _totalSupply;
string private _name;
string private _symbol;
uint8 private _decimals;
event Transfer(
address indexed from,
address indexed to,
uint256 value
);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
constructor (string memory name, string memory symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @dev Returns the name of the token.
*/
function name() public view returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view 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 {_setupDecimals} is
* called.
*
* 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 returns (uint8) {
return _decimals;
}
/**
* @dev Total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev Gets the balance of the specified address.
* @param owner The address to query the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address owner) public view returns (uint256) {
return _balances[owner];
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param owner address The address which owns the funds.
* @param spender address The address which will spend the funds.
* @return A uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(
address owner,
address spender
)
public
view
returns (uint256)
{
return _allowed[owner][spender];
}
/**
* @dev Transfer token for a specified address
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/
function transfer(address to, uint256 value) public returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
* 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
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
*/
function approve(address spender, uint256 value) public returns (bool) {
require(spender != address(0));
_allowed[msg.sender][spender] = value;
emit Approval(msg.sender, spender, value);
return true;
}
/**
* @dev Transfer tokens from one address to another
* @param from address The address which you want to send tokens from
* @param to address The address which you want to transfer to
* @param value uint256 the amount of tokens to be transferred
*/
function transferFrom(
address from,
address to,
uint256 value
)
public
returns (bool)
{
require(value <= _allowed[from][msg.sender]);
_allowed[from][msg.sender] = _allowed[from][msg.sender].sub(value);
_transfer(from, to, value);
return true;
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
* approve should be called when allowed_[_spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param spender The address which will spend the funds.
* @param addedValue The amount of tokens to increase the allowance by.
*/
function increaseAllowance(
address spender,
uint256 addedValue
)
public
returns (bool)
{
require(spender != address(0));
_allowed[msg.sender][spender] = (
_allowed[msg.sender][spender].add(addedValue));
emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
* approve should be called when allowed_[_spender] == 0. To decrement
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param spender The address which will spend the funds.
* @param subtractedValue The amount of tokens to decrease the allowance by.
*/
function decreaseAllowance(
address spender,
uint256 subtractedValue
)
public
returns (bool)
{
require(spender != address(0));
_allowed[msg.sender][spender] = (
_allowed[msg.sender][spender].sub(subtractedValue));
emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
return true;
}
/**
* @dev Transfer token for a specified addresses
* @param from The address to transfer from.
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/
function _transfer(address from, address to, uint256 value) internal {
require(value <= _balances[from]);
require(to != address(0));
_balances[from] = _balances[from].sub(value);
_balances[to] = _balances[to].add(value);
emit Transfer(from, to, value);
}
/**
* @dev Internal function that mints an amount of the token and assigns it to
* an account. This encapsulates the modification of balances such that the
* proper events are emitted.
* @param account The account that will receive the created tokens.
* @param value The amount that will be created.
*/
function _mint(address account, uint256 value) internal {
require(account != address(0));
_totalSupply = _totalSupply.add(value);
_balances[account] = _balances[account].add(value);
emit Transfer(address(0), account, value);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account.
* @param account The account whose tokens will be burnt.
* @param value The amount that will be burnt.
*/
function _burn(address account, uint256 value) internal {
require(account != address(0));
require(value <= _balances[account]);
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account, deducting from the sender's allowance for said account. Uses the
* internal burn function.
* @param account The account whose tokens will be burnt.
* @param value The amount that will be burnt.
*/
function _burnFrom(address account, uint256 value) internal {
require(value <= _allowed[account][msg.sender]);
// Should https://github.com/OpenZeppelin/zeppelin-solidity/issues/707 be accepted,
// this function needs to emit an event with the updated approval.
_allowed[account][msg.sender] = _allowed[account][msg.sender].sub(
value);
_burn(account, value);
}
}
contract TomoE is ERC20 {
/*
* Events
*/
event Confirmation(address indexed sender, uint indexed transactionId);
event Revocation(address indexed sender, uint indexed transactionId);
event Submission(uint indexed transactionId);
event Execution(uint indexed transactionId);
event ExecutionFailure(uint indexed transactionId);
event OwnerAddition(address indexed owner);
event OwnerRemoval(address indexed owner);
event RequirementChange(uint required);
event TokenBurn(uint256 indexed burnID, address indexed burner, uint256 value, bytes data);
/*
* Constants
*/
uint constant public MAX_OWNER_COUNT = 50;
uint public WITHDRAW_FEE = 0;
/*
* Storage
*/
mapping (uint => Transaction) public transactions;
mapping (uint => mapping (address => bool)) public confirmations;
mapping (address => bool) public isOwner;
address[] public owners;
address public issuer;
uint public required;
uint public transactionCount;
TokenBurnData[] public burnList;
struct TokenBurnData {
uint256 value;
address burner;
bytes data;
}
struct Transaction {
address destination;
uint value;
bytes data; //data is used in transactions altering owner list
bool executed;
}
/*
* Modifiers
*/
modifier onlyWallet() {
require(msg.sender == address(this));
_;
}
modifier ownerDoesNotExist(address owner) {
require(!isOwner[owner]);
_;
}
modifier ownerExists(address owner) {
require(isOwner[owner]);
_;
}
modifier transactionExists(uint transactionId) {
require(transactions[transactionId].destination != 0);
_;
}
modifier confirmed(uint transactionId, address owner) {
require(confirmations[transactionId][owner]);
_;
}
modifier notConfirmed(uint transactionId, address owner) {
require(!confirmations[transactionId][owner]);
_;
}
modifier notExecuted(uint transactionId) {
require(!transactions[transactionId].executed);
_;
}
modifier notNull(address _address) {
require(_address != 0);
_;
}
modifier validRequirement(uint ownerCount, uint _required) {
require(ownerCount <= MAX_OWNER_COUNT
&& _required <= ownerCount
&& _required != 0
&& ownerCount != 0);
_;
}
modifier onlyIssuer() {
require(msg.sender == issuer);
_;
}
/*
* Public functions
*/
/// @dev Contract constructor sets initial owners and required number of confirmations.
/// @param _owners List of initial owners.
/// @param _required Number of required confirmations.
constructor (address[] _owners,
uint _required, string memory _name,
string memory _symbol, uint8 _decimals,
uint256 cap,
uint256 withdrawFee
) ERC20(_name, _symbol, _decimals) public validRequirement(_owners.length, _required) {
_mint(msg.sender, cap);
issuer = msg.sender;
WITHDRAW_FEE = withdrawFee;
for (uint i=0; i<_owners.length; i++) {
require(!isOwner[_owners[i]] && _owners[i] != 0);
isOwner[_owners[i]] = true;
}
owners = _owners;
required = _required;
}
/// @dev Allows to add a new owner. Transaction has to be sent by wallet.
/// @param owner Address of new owner.
function addOwner(address owner)
public
onlyWallet
ownerDoesNotExist(owner)
notNull(owner)
validRequirement(owners.length + 1, required)
{
isOwner[owner] = true;
owners.push(owner);
OwnerAddition(owner);
}
/// @dev Allows to remove an owner. Transaction has to be sent by wallet.
/// @param owner Address of owner.
function removeOwner(address owner)
public
onlyWallet
ownerExists(owner)
{
isOwner[owner] = false;
for (uint i=0; i<owners.length - 1; i++)
if (owners[i] == owner) {
owners[i] = owners[owners.length - 1];
break;
}
owners.length -= 1;
if (required > owners.length)
changeRequirement(owners.length);
OwnerRemoval(owner);
}
/// @dev Allows to replace an owner with a new owner. Transaction has to be sent by wallet.
/// @param owner Address of owner to be replaced.
/// @param newOwner Address of new owner.
function replaceOwner(address owner, address newOwner)
public
onlyWallet
ownerExists(owner)
ownerDoesNotExist(newOwner)
{
for (uint i=0; i<owners.length; i++)
if (owners[i] == owner) {
owners[i] = newOwner;
break;
}
isOwner[owner] = false;
isOwner[newOwner] = true;
OwnerRemoval(owner);
OwnerAddition(newOwner);
}
/// @dev Allows to change the number of required confirmations. Transaction has to be sent by wallet.
/// @param _required Number of required confirmations.
function changeRequirement(uint _required)
public
onlyWallet
validRequirement(owners.length, _required)
{
required = _required;
RequirementChange(_required);
}
/// @dev Allows an owner to submit and confirm a transaction.
/// @param destination Transaction target address.
/// @param value Transaction ether value.
/// @param data Transaction data payload.
/// @return Returns transaction ID.
function submitTransaction(address destination, uint value, bytes data)
public
returns (uint transactionId)
{
//transaction is considered as minting if no data provided, otherwise it's owner changing transaction
transactionId = addTransaction(destination, value, data);
confirmTransaction(transactionId);
}
/// @dev Allows an owner to confirm a transaction.
/// @param transactionId Transaction ID.
function confirmTransaction(uint transactionId)
public
ownerExists(msg.sender)
transactionExists(transactionId)
notConfirmed(transactionId, msg.sender)
{
confirmations[transactionId][msg.sender] = true;
Confirmation(msg.sender, transactionId);
executeTransaction(transactionId);
}
/// @dev Allows an owner to revoke a confirmation for a transaction.
/// @param transactionId Transaction ID.
function revokeConfirmation(uint transactionId)
public
ownerExists(msg.sender)
confirmed(transactionId, msg.sender)
notExecuted(transactionId)
{
confirmations[transactionId][msg.sender] = false;
Revocation(msg.sender, transactionId);
}
/// @dev Allows an user to burn the token.
function burn(uint value, bytes data)
public
{
require(value > WITHDRAW_FEE);
super._burn(msg.sender, value);
if (WITHDRAW_FEE > 0) {
super._mint(issuer, WITHDRAW_FEE);
}
uint256 burnValue = value.sub(WITHDRAW_FEE);
burnList.push(TokenBurnData({
value: burnValue,
burner: msg.sender,
data: data
}));
TokenBurn(burnList.length - 1, msg.sender, burnValue, data);
}
/// @dev Allows anyone to execute a confirmed transaction.
/// @param transactionId Transaction ID.
function executeTransaction(uint transactionId)
public
ownerExists(msg.sender)
confirmed(transactionId, msg.sender)
notExecuted(transactionId)
{
if (isConfirmed(transactionId)) {
Transaction storage txn = transactions[transactionId];
txn.executed = true;
// just need multisig for minting - freely burn
if (txn.data.length == 0) {
//execute minting transaction
txn.value = txn.value;
super._mint(txn.destination, txn.value);
Execution(transactionId);
} else {
//transaction that alters the owners list
if (txn.destination.call.value(txn.value)(txn.data))
Execution(transactionId);
else {
ExecutionFailure(transactionId);
txn.executed = false;
}
}
}
}
/// @dev Returns the confirmation status of a transaction.
/// @param transactionId Transaction ID.
/// @return Confirmation status.
function isConfirmed(uint transactionId)
public
constant
returns (bool)
{
uint count = 0;
for (uint i=0; i<owners.length; i++) {
if (confirmations[transactionId][owners[i]])
count += 1;
if (count == required)
return true;
}
}
/*
* Internal functions
*/
/// @dev Adds a new transaction to the transaction mapping, if transaction does not exist yet.
/// @param destination Transaction target address.
/// @param value Transaction ether value.
/// @param data Transaction data payload.
/// @return Returns transaction ID.
function addTransaction(address destination, uint value, bytes data)
internal
notNull(destination)
returns (uint transactionId)
{
transactionId = transactionCount;
transactions[transactionId] = Transaction({
destination: destination,
value: value,
data: data,
executed: false
});
transactionCount += 1;
Submission(transactionId);
}
/*
* Web3 call functions
*/
/// @dev Returns number of confirmations of a transaction.
/// @param transactionId Transaction ID.
/// @return Number of confirmations.
function getConfirmationCount(uint transactionId)
public
constant
returns (uint count)
{
for (uint i=0; i<owners.length; i++)
if (confirmations[transactionId][owners[i]])
count += 1;
}
/// @dev Returns total number of transactions after filers are applied.
/// @param pending Include pending transactions.
/// @param executed Include executed transactions.
/// @return Total number of transactions after filters are applied.
function getTransactionCount(bool pending, bool executed)
public
constant
returns (uint count)
{
for (uint i=0; i<transactionCount; i++)
if ( pending && !transactions[i].executed
|| executed && transactions[i].executed)
count += 1;
}
/// @dev Returns list of owners.
/// @return List of owner addresses.
function getOwners()
public
constant
returns (address[])
{
return owners;
}
/// @dev Returns array with owner addresses, which confirmed transaction.
/// @param transactionId Transaction ID.
/// @return Returns array of owner addresses.
function getConfirmations(uint transactionId)
public
constant
returns (address[] _confirmations)
{
address[] memory confirmationsTemp = new address[](owners.length);
uint count = 0;
uint i;
for (i=0; i<owners.length; i++)
if (confirmations[transactionId][owners[i]]) {
confirmationsTemp[count] = owners[i];
count += 1;
}
_confirmations = new address[](count);
for (i=0; i<count; i++)
_confirmations[i] = confirmationsTemp[i];
}
/// @dev Returns list of transaction IDs in defined range.
/// @param from Index start position of transaction array.
/// @param to Index end position of transaction array.
/// @param pending Include pending transactions.
/// @param executed Include executed transactions.
/// @return Returns array of transaction IDs.
function getTransactionIds(uint from, uint to, bool pending, bool executed)
public
constant
returns (uint[] _transactionIds)
{
uint end = to > transactionCount? transactionCount: to;
uint[] memory transactionIdsTemp = new uint[](end - from);
uint count = 0;
uint i;
for (i = from; i < to; i++) {
if ((pending && !transactions[i].executed)
|| (executed && transactions[i].executed))
{
transactionIdsTemp[count] = i;
count += 1;
}
}
_transactionIds = new uint[](count);
for (i = 0; i < count; i++)
_transactionIds[i] = transactionIdsTemp[i];
}
function getBurnCount() public view returns (uint256) {
return burnList.length;
}
function getBurn(uint burnId) public view returns (address _burner, uint256 _value, bytes _data) {
_burner = burnList[burnId].burner;
_value = burnList[burnId].value;
_data = burnList[burnId].data;
}
/// @dev Allows to tramsfer contact issuer
function transferIssuer(address newIssuer)
public
onlyIssuer
notNull(newIssuer)
{
issuer = newIssuer;
}
function setWithdrawFee(uint256 withdrawFee) public onlyIssuer {
WITHDRAW_FEE = withdrawFee;
}
}