Contract Source Code:
// SPDX-License-Identifier: GPL-3.0
pragma solidity =0.6.12;
import "./interfaces/IFactory.sol";
import "./libraries/TransferHelper.sol";
import "./interfaces/IRouter02.sol";
import "./libraries/PairLibrary.sol";
import "./libraries/SafeMath.sol";
import "./interfaces/IERC20.sol";
import "./interfaces/IWETH.sol";
contract Router is IRouter02 {
using SafeMath for uint256;
address public immutable override factory;
address public immutable override WETH;
modifier ensure(uint256 deadline) {
require(deadline >= block.timestamp, "Router: 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,
uint256 amountADesired,
uint256 amountBDesired,
uint256 amountAMin,
uint256 amountBMin
) internal virtual returns (uint256 amountA, uint256 amountB) {
// create the pair if it doesn't exist yet
if (IFactory(factory).getPair(tokenA, tokenB) == address(0)) {
IFactory(factory).createPair(tokenA, tokenB);
}
(uint256 reserveA, uint256 reserveB) = PairLibrary.getReserves(factory, tokenA, tokenB);
if (reserveA == 0 && reserveB == 0) {
(amountA, amountB) = (amountADesired, amountBDesired);
} else {
uint256 amountBOptimal = PairLibrary.quote(amountADesired, reserveA, reserveB);
if (amountBOptimal <= amountBDesired) {
require(amountBOptimal >= amountBMin, "Router: INSUFFICIENT_B_AMOUNT");
(amountA, amountB) = (amountADesired, amountBOptimal);
} else {
uint256 amountAOptimal = PairLibrary.quote(amountBDesired, reserveB, reserveA);
assert(amountAOptimal <= amountADesired);
require(amountAOptimal >= amountAMin, "Router: INSUFFICIENT_A_AMOUNT");
(amountA, amountB) = (amountAOptimal, amountBDesired);
}
}
}
function addLiquidity(
address tokenA,
address tokenB,
uint256 amountADesired,
uint256 amountBDesired,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
)
external
virtual
override
ensure(deadline)
returns (
uint256 amountA,
uint256 amountB,
uint256 liquidity
)
{
(amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
address pair = PairLibrary.pairFor(factory, tokenA, tokenB);
TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA);
TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB);
liquidity = IPair(pair).mint(to);
}
function addLiquidityETH(
address token,
uint256 amountTokenDesired,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
)
external
payable
virtual
override
ensure(deadline)
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
)
{
(amountToken, amountETH) = _addLiquidity(token, WETH, amountTokenDesired, msg.value, amountTokenMin, amountETHMin);
address pair = PairLibrary.pairFor(factory, token, WETH);
TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken);
IWETH(WETH).deposit{value: amountETH}();
assert(IWETH(WETH).transfer(pair, amountETH));
liquidity = IPair(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,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
) public virtual override ensure(deadline) returns (uint256 amountA, uint256 amountB) {
address pair = PairLibrary.pairFor(factory, tokenA, tokenB);
IPair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
(uint256 amount0, uint256 amount1) = IPair(pair).burn(to);
(address token0, ) = PairLibrary.sortTokens(tokenA, tokenB);
(amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
require(amountA >= amountAMin, "Router: INSUFFICIENT_A_AMOUNT");
require(amountB >= amountBMin, "Router: INSUFFICIENT_B_AMOUNT");
}
function removeLiquidityETH(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) public virtual override ensure(deadline) returns (uint256 amountToken, uint256 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,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external virtual override returns (uint256 amountA, uint256 amountB) {
address pair = PairLibrary.pairFor(factory, tokenA, tokenB);
uint256 value = approveMax ? uint256(-1) : liquidity;
IPair(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,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external virtual override returns (uint256 amountToken, uint256 amountETH) {
address pair = PairLibrary.pairFor(factory, token, WETH);
uint256 value = approveMax ? uint256(-1) : liquidity;
IPair(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,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) public virtual override ensure(deadline) returns (uint256 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,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external virtual override returns (uint256 amountETH) {
address pair = PairLibrary.pairFor(factory, token, WETH);
uint256 value = approveMax ? uint256(-1) : liquidity;
IPair(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(
uint256[] memory amounts,
address[] memory path,
address _to
) internal virtual {
for (uint256 i; i < path.length - 1; i++) {
(address input, address output) = (path[i], path[i + 1]);
(address token0, ) = PairLibrary.sortTokens(input, output);
uint256 amountOut = amounts[i + 1];
(uint256 amount0Out, uint256 amount1Out) = input == token0 ? (uint256(0), amountOut) : (amountOut, uint256(0));
address to = i < path.length - 2 ? PairLibrary.pairFor(factory, output, path[i + 2]) : _to;
IPair(PairLibrary.pairFor(factory, input, output)).swap(amount0Out, amount1Out, to, new bytes(0));
}
}
function swapExactTokensForTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external virtual override ensure(deadline) returns (uint256[] memory amounts) {
amounts = PairLibrary.getAmountsOut(factory, amountIn, path);
require(amounts[amounts.length - 1] >= amountOutMin, "Router: INSUFFICIENT_OUTPUT_AMOUNT");
TransferHelper.safeTransferFrom(path[0], msg.sender, PairLibrary.pairFor(factory, path[0], path[1]), amounts[0]);
_swap(amounts, path, to);
}
function swapTokensForExactTokens(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external virtual override ensure(deadline) returns (uint256[] memory amounts) {
amounts = PairLibrary.getAmountsIn(factory, amountOut, path);
require(amounts[0] <= amountInMax, "Router: EXCESSIVE_INPUT_AMOUNT");
TransferHelper.safeTransferFrom(path[0], msg.sender, PairLibrary.pairFor(factory, path[0], path[1]), amounts[0]);
_swap(amounts, path, to);
}
function swapExactETHForTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable virtual override ensure(deadline) returns (uint256[] memory amounts) {
require(path[0] == WETH, "Router: INVALID_PATH");
amounts = PairLibrary.getAmountsOut(factory, msg.value, path);
require(amounts[amounts.length - 1] >= amountOutMin, "Router: INSUFFICIENT_OUTPUT_AMOUNT");
IWETH(WETH).deposit{value: amounts[0]}();
assert(IWETH(WETH).transfer(PairLibrary.pairFor(factory, path[0], path[1]), amounts[0]));
_swap(amounts, path, to);
}
function swapTokensForExactETH(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external virtual override ensure(deadline) returns (uint256[] memory amounts) {
require(path[path.length - 1] == WETH, "Router: INVALID_PATH");
amounts = PairLibrary.getAmountsIn(factory, amountOut, path);
require(amounts[0] <= amountInMax, "Router: EXCESSIVE_INPUT_AMOUNT");
TransferHelper.safeTransferFrom(path[0], msg.sender, PairLibrary.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(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external virtual override ensure(deadline) returns (uint256[] memory amounts) {
require(path[path.length - 1] == WETH, "Router: INVALID_PATH");
amounts = PairLibrary.getAmountsOut(factory, amountIn, path);
require(amounts[amounts.length - 1] >= amountOutMin, "Router: INSUFFICIENT_OUTPUT_AMOUNT");
TransferHelper.safeTransferFrom(path[0], msg.sender, PairLibrary.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(
uint256 amountOut,
address[] calldata path,
address to,
uint256 deadline
) external payable virtual override ensure(deadline) returns (uint256[] memory amounts) {
require(path[0] == WETH, "Router: INVALID_PATH");
amounts = PairLibrary.getAmountsIn(factory, amountOut, path);
require(amounts[0] <= msg.value, "Router: EXCESSIVE_INPUT_AMOUNT");
IWETH(WETH).deposit{value: amounts[0]}();
assert(IWETH(WETH).transfer(PairLibrary.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 (uint256 i; i < path.length - 1; i++) {
(address input, address output) = (path[i], path[i + 1]);
(address token0, ) = PairLibrary.sortTokens(input, output);
IPair pair = IPair(PairLibrary.pairFor(factory, input, output));
uint256 amountInput;
uint256 amountOutput;
{
// scope to avoid stack too deep errors
(uint256 reserve0, uint256 reserve1, ) = pair.getReserves();
(uint256 reserveInput, uint256 reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
amountOutput = PairLibrary.getAmountOut(amountInput, reserveInput, reserveOutput, pair.feeAmount());
}
(uint256 amount0Out, uint256 amount1Out) = input == token0 ? (uint256(0), amountOutput) : (amountOutput, uint256(0));
address to = i < path.length - 2 ? PairLibrary.pairFor(factory, output, path[i + 2]) : _to;
pair.swap(amount0Out, amount1Out, to, new bytes(0));
}
}
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external virtual override ensure(deadline) {
TransferHelper.safeTransferFrom(path[0], msg.sender, PairLibrary.pairFor(factory, path[0], path[1]), amountIn);
uint256 balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
_swapSupportingFeeOnTransferTokens(path, to);
require(IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin, "Router: INSUFFICIENT_OUTPUT_AMOUNT");
}
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable virtual override ensure(deadline) {
require(path[0] == WETH, "Router: INVALID_PATH");
uint256 amountIn = msg.value;
IWETH(WETH).deposit{value: amountIn}();
assert(IWETH(WETH).transfer(PairLibrary.pairFor(factory, path[0], path[1]), amountIn));
uint256 balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
_swapSupportingFeeOnTransferTokens(path, to);
require(IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin, "Router: INSUFFICIENT_OUTPUT_AMOUNT");
}
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external virtual override ensure(deadline) {
require(path[path.length - 1] == WETH, "Router: INVALID_PATH");
TransferHelper.safeTransferFrom(path[0], msg.sender, PairLibrary.pairFor(factory, path[0], path[1]), amountIn);
_swapSupportingFeeOnTransferTokens(path, address(this));
uint256 amountOut = IERC20(WETH).balanceOf(address(this));
require(amountOut >= amountOutMin, "Router: INSUFFICIENT_OUTPUT_AMOUNT");
IWETH(WETH).withdraw(amountOut);
TransferHelper.safeTransferETH(to, amountOut);
}
// **** LIBRARY FUNCTIONS ****
function quote(
uint256 amountA,
uint256 reserveA,
uint256 reserveB
) public pure virtual override returns (uint256 amountB) {
return PairLibrary.quote(amountA, reserveA, reserveB);
}
function getAmountOut(
uint256 amountIn,
uint256 reserveIn,
uint256 reserveOut,
uint256 feeAmount
) public pure virtual override returns (uint256 amountOut) {
return PairLibrary.getAmountOut(amountIn, reserveIn, reserveOut, feeAmount);
}
function getAmountIn(
uint256 amountOut,
uint256 reserveIn,
uint256 reserveOut,
uint256 feeAmount
) public pure virtual override returns (uint256 amountIn) {
return PairLibrary.getAmountIn(amountOut, reserveIn, reserveOut, feeAmount);
}
function getAmountsOut(uint256 amountIn, address[] memory path) public view virtual override returns (uint256[] memory amounts) {
return PairLibrary.getAmountsOut(factory, amountIn, path);
}
function getAmountsIn(uint256 amountOut, address[] memory path) public view virtual override returns (uint256[] memory amounts) {
return PairLibrary.getAmountsIn(factory, amountOut, path);
}
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.6.0;
// 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,
uint256 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,
uint256 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,
uint256 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, uint256 value) internal {
(bool success, ) = to.call{value: value}(new bytes(0));
require(success, "TransferHelper: ETH_TRANSFER_FAILED");
}
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity =0.6.12;
// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
library SafeMath {
function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
require((z = x + y) >= x, "ds-math-add-overflow");
}
function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
require((z = x - y) <= x, "ds-math-sub-underflow");
}
function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
require(y == 0 || (z = x * y) / y == x, "ds-math-mul-overflow");
}
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.6.12;
import "../interfaces/IPair.sol";
import "./SafeMath.sol";
library PairLibrary {
using SafeMath for uint256;
// 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, "PairLibrary: IDENTICAL_ADDRESSES");
(token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
require(token0 != address(0), "PairLibrary: 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(
uint256(
keccak256(
abi.encodePacked(
hex"ff",
factory,
keccak256(abi.encodePacked(token0, token1)),
hex'b174fb9703cd825ac38ca3cf781a2750d5ee57f4268806e0bca9bcd3d74b67b5' // new
// hex"049f32ebc831c324153e0852a313f2be077e76367383aa39f9e12ad395265ab2" // init code hash for tests (hardhat)
)
)
)
);
}
// fetches and sorts the reserves for a pair
function getReserves(
address factory,
address tokenA,
address tokenB
) internal view returns (uint256 reserveA, uint256 reserveB) {
(address token0, ) = sortTokens(tokenA, tokenB);
(uint256 reserve0, uint256 reserve1, ) = IPair(pairFor(factory, tokenA, tokenB)).getReserves();
(reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
}
// fetches and sorts the reserves for a pair
function getReservesAndFeeAmount(
address factory,
address tokenA,
address tokenB
)
internal
view
returns (
uint256 reserveA,
uint256 reserveB,
uint256 feeAmount
)
{
(address token0, ) = sortTokens(tokenA, tokenB);
IPair pair = IPair(pairFor(factory, tokenA, tokenB));
(uint256 reserve0, uint256 reserve1, ) = pair.getReserves();
feeAmount = pair.feeAmount();
(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(
uint256 amountA,
uint256 reserveA,
uint256 reserveB
) internal pure returns (uint256 amountB) {
require(amountA > 0, "PairLibrary: INSUFFICIENT_AMOUNT");
require(reserveA > 0 && reserveB > 0, "PairLibrary: 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(
uint256 amountIn,
uint256 reserveIn,
uint256 reserveOut,
uint256 feeAmount
) internal pure returns (uint256 amountOut) {
require(amountIn > 0, "PairLibrary: INSUFFICIENT_INPUT_AMOUNT");
require(reserveIn > 0 && reserveOut > 0, "PairLibrary: INSUFFICIENT_LIQUIDITY");
uint256 amountInWithFee = amountIn.mul(100000 - feeAmount);
uint256 numerator = amountInWithFee.mul(reserveOut);
uint256 denominator = reserveIn.mul(100000).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(
uint256 amountOut,
uint256 reserveIn,
uint256 reserveOut,
uint256 feeAmount
) internal pure returns (uint256 amountIn) {
require(amountOut > 0, "PairLibrary: INSUFFICIENT_OUTPUT_AMOUNT");
require(reserveIn > 0 && reserveOut > 0, "PairLibrary: INSUFFICIENT_LIQUIDITY");
uint256 numerator = reserveIn.mul(amountOut).mul(100000);
uint256 denominator = reserveOut.sub(amountOut).mul(100000 - feeAmount);
amountIn = (numerator / denominator).add(1);
}
// performs chained getAmountOut calculations on any number of pairs
function getAmountsOut(
address factory,
uint256 amountIn,
address[] memory path
) internal view returns (uint256[] memory amounts) {
require(path.length >= 2, "PairLibrary: INVALID_PATH");
amounts = new uint256[](path.length);
amounts[0] = amountIn;
for (uint256 i; i < path.length - 1; i++) {
(uint256 reserveIn, uint256 reserveOut, uint256 feeAmount) = getReservesAndFeeAmount(factory, path[i], path[i + 1]);
amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut, feeAmount);
}
}
// performs chained getAmountIn calculations on any number of pairs
function getAmountsIn(
address factory,
uint256 amountOut,
address[] memory path
) internal view returns (uint256[] memory amounts) {
require(path.length >= 2, "PairLibrary: INVALID_PATH");
amounts = new uint256[](path.length);
amounts[amounts.length - 1] = amountOut;
for (uint256 i = path.length - 1; i > 0; i--) {
(uint256 reserveIn, uint256 reserveOut, uint256 feeAmount) = getReservesAndFeeAmount(factory, path[i - 1], path[i]);
amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut, feeAmount);
}
}
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.6.12;
interface IWETH {
function deposit() external payable;
function transfer(address to, uint256 value) external returns (bool);
function withdraw(uint256) external;
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.6.12;
import "./IRouter01.sol";
interface IRouter02 is IRouter01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) external returns (uint256 amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountETH);
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.6.12;
interface IRouter01 {
function factory() external pure returns (address);
function WETH() external pure returns (address);
function addLiquidity(
address tokenA,
address tokenB,
uint256 amountADesired,
uint256 amountBDesired,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
)
external
returns (
uint256 amountA,
uint256 amountB,
uint256 liquidity
);
function addLiquidityETH(
address token,
uint256 amountTokenDesired,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
)
external
payable
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
);
function removeLiquidity(
address tokenA,
address tokenB,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
) external returns (uint256 amountA, uint256 amountB);
function removeLiquidityETH(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) external returns (uint256 amountToken, uint256 amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountA, uint256 amountB);
function removeLiquidityETHWithPermit(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountToken, uint256 amountETH);
function swapExactTokensForTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapTokensForExactTokens(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapExactETHForTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable returns (uint256[] memory amounts);
function swapTokensForExactETH(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapExactTokensForETH(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapETHForExactTokens(
uint256 amountOut,
address[] calldata path,
address to,
uint256 deadline
) external payable returns (uint256[] memory amounts);
function quote(
uint256 amountA,
uint256 reserveA,
uint256 reserveB
) external pure returns (uint256 amountB);
function getAmountOut(
uint256 amountIn,
uint256 reserveIn,
uint256 reserveOut,
uint256 feeAmount
) external pure returns (uint256 amountOut);
function getAmountIn(
uint256 amountOut,
uint256 reserveIn,
uint256 reserveOut,
uint256 feeAmount
) external pure returns (uint256 amountIn);
function getAmountsOut(uint256 amountIn, address[] calldata path) external view returns (uint256[] memory amounts);
function getAmountsIn(uint256 amountOut, address[] calldata path) external view returns (uint256[] memory amounts);
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.5.0;
interface IPair {
event Approval(address indexed owner, address indexed spender, uint256 value);
event Transfer(address indexed from, address indexed to, uint256 value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint256);
function balanceOf(address owner) external view returns (uint256);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 value) external returns (bool);
function transfer(address to, uint256 value) external returns (bool);
function transferFrom(
address from,
address to,
uint256 value
) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint256);
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
event FeeAmountUpdated(uint256 prevFeeAmount, uint256 feeAmount);
event Mint(address indexed sender, uint256 amount0, uint256 amount1);
event Burn(address indexed sender, uint256 amount0, uint256 amount1, address indexed to);
event Swap(address indexed sender, uint256 amount0In, uint256 amount1In, uint256 amount0Out, uint256 amount1Out, address indexed to);
event Sync(uint112 reserve0, uint112 reserve1);
function MINIMUM_LIQUIDITY() external pure returns (uint256);
function factory() external view returns (address);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves()
external
view
returns (
uint112 reserve0,
uint112 reserve1,
uint32 blockTimestampLast
);
function price0CumulativeLast() external view returns (uint256);
function price1CumulativeLast() external view returns (uint256);
function kLast() external view returns (uint256);
function mint(address to) external returns (uint256 liquidity);
function burn(address to) external returns (uint256 amount0, uint256 amount1);
function swap(
uint256 amount0Out,
uint256 amount1Out,
address to,
bytes calldata data
) external;
function skim(address to) external;
function sync() external;
function initialize(address, address) external;
function feeAmount() external view returns (uint256);
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.5.0;
interface IFactory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint256);
function feeTo() external view returns (address);
function feeToSetter() external view returns (address);
function getPair(address tokenA, address tokenB) external view returns (address pair);
function allPairs(uint256) external view returns (address pair);
function allPairsLength() external view returns (uint256);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
function ownerFeeShare() external view returns (uint256);
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.5.0;
interface IERC20 {
event Approval(address indexed owner, address indexed spender, uint256 value);
event Transfer(address indexed from, address indexed to, uint256 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 (uint256);
function balanceOf(address owner) external view returns (uint256);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 value) external returns (bool);
function transfer(address to, uint256 value) external returns (bool);
function transferFrom(
address from,
address to,
uint256 value
) external returns (bool);
}