Contract Source Code:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./ERC20Snapshot.sol";
contract Myobu is ERC20Snapshot {
address public override DAO; // solhint-disable-line
address public override myobuSwap;
bool private antiLiqBot;
constructor(address payable addr1) MyobuBase(addr1) {
setFees(Fees(10, 10, 10, 10));
}
modifier onlySupportedPair(address pair) {
require(taxedPair(pair), "Pair is not supported");
_;
}
modifier onlyMyobuswapOnAntiLiq() {
require(!antiLiqBot || _msgSender() == myobuSwap, "Use MyobuSwap");
_;
}
modifier checkDeadline(uint256 deadline) {
require(block.timestamp <= deadline, "Transaction expired");
_;
}
function setDAO(address newDAO) external onlyOwner {
DAO = newDAO;
emit DAOChanged(newDAO);
}
function setMyobuSwap(address newMyobuSwap) external onlyOwner {
myobuSwap = newMyobuSwap;
emit MyobuSwapChanged(newMyobuSwap);
}
function snapshot() external returns (uint256) {
require(_msgSender() == owner() || _msgSender() == DAO);
return _snapshot();
}
function setAntiLiqBot(bool setTo) external virtual onlyOwner {
antiLiqBot = setTo;
}
function noFeeAddLiquidityETH(LiquidityETHParams calldata params)
external
payable
override
onlySupportedPair(params.pair)
checkDeadline(params.deadline)
onlyMyobuswapOnAntiLiq
lockTheSwap
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
)
{
_transfer(_msgSender(), address(this), params.amountTokenOrLP);
uint256 beforeBalance = address(this).balance - msg.value;
(amountToken, amountETH, liquidity) = IUniswapV2Router(
_routerFor[params.pair]
).addLiquidityETH{value: msg.value}(
address(this),
params.amountTokenOrLP,
params.amountTokenMin,
params.amountETHMin,
params.to,
block.timestamp
);
// router refunds to this address, refund all back to sender
if (address(this).balance > beforeBalance) {
payable(_msgSender()).transfer(
address(this).balance - beforeBalance
);
}
emit LiquidityAddedETH(params.pair, amountToken, amountETH, liquidity);
}
function noFeeRemoveLiquidityETH(LiquidityETHParams calldata params)
external
override
onlySupportedPair(params.pair)
checkDeadline(params.deadline)
lockTheSwap
returns (uint256 amountToken, uint256 amountETH)
{
MyobuLib.transferTokens(
params.pair,
_msgSender(),
address(this),
params.amountTokenOrLP
);
(amountToken, amountETH) = IUniswapV2Router(_routerFor[params.pair])
.removeLiquidityETH(
address(this),
params.amountTokenOrLP,
params.amountTokenMin,
params.amountETHMin,
params.to,
block.timestamp
);
emit LiquidityRemovedETH(
params.pair,
amountToken,
amountETH,
params.amountTokenOrLP
);
}
function noFeeAddLiquidity(AddLiquidityParams calldata params)
external
override
onlySupportedPair(params.pair)
checkDeadline(params.deadline)
onlyMyobuswapOnAntiLiq
lockTheSwap
returns (
uint256 amountMyobu,
uint256 amountToken,
uint256 liquidity
)
{
address token = MyobuLib.tokenFor(params.pair);
uint256 beforeBalance = IERC20(token).balanceOf(address(this));
_transfer(_msgSender(), address(this), params.amountToken);
MyobuLib.transferTokens(
token,
_msgSender(),
address(this),
params.amountTokenB
);
(amountToken, amountMyobu, liquidity) = IUniswapV2Router(
_routerFor[params.pair]
).addLiquidity(
token,
address(this),
params.amountTokenB,
params.amountToken,
params.amountTokenBMin,
params.amountTokenMin,
params.to,
block.timestamp
);
// router refunds to this address, refund all back to sender
uint256 currentBalance = IERC20(token).balanceOf(address(this));
if (currentBalance > beforeBalance) {
IERC20(token).transfer(
_msgSender(),
currentBalance - beforeBalance
);
}
emit LiquidityAdded(params.pair, amountMyobu, amountToken, liquidity);
}
function noFeeRemoveLiquidity(RemoveLiquidityParams calldata params)
external
override
onlySupportedPair(params.pair)
checkDeadline(params.deadline)
lockTheSwap
returns (uint256 amountMyobu, uint256 amountToken)
{
MyobuLib.transferTokens(
params.pair,
_msgSender(),
address(this),
params.amountLP
);
(amountToken, amountMyobu) = IUniswapV2Router(_routerFor[params.pair])
.removeLiquidity(
MyobuLib.tokenFor(params.pair),
address(this),
params.amountLP,
params.amountTokenBMin,
params.amountTokenMin,
params.to,
block.timestamp
);
emit LiquidityRemoved(
params.pair,
amountMyobu,
amountToken,
params.amountLP
);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./Utils/Arrays.sol";
import "./Utils/Counters.sol";
import "./MyobuBase.sol";
/**
* @dev This contract extends an ERC20 token with a snapshot mechanism. When a snapshot is created, the balances and
* total supply at the time are recorded for later access.
*
* This can be used to safely create mechanisms based on token balances such as trustless dividends or weighted voting.
* In naive implementations it's possible to perform a "double spend" attack by reusing the same balance from different
* accounts. By using snapshots to calculate dividends or voting power, those attacks no longer apply. It can also be
* used to create an efficient ERC20 forking mechanism.
*
* Snapshots are created by the internal {_snapshot} function, which will emit the {Snapshot} event and return a
* snapshot id. To get the total supply at the time of a snapshot, call the function {totalSupplyAt} with the snapshot
* id. To get the balance of an account at the time of a snapshot, call the {balanceOfAt} function with the snapshot id
* and the account address.
*
* NOTE: Snapshot policy can be customized by overriding the {_getCurrentSnapshotId} method. For example, having it
* return `block.number` will trigger the creation of snapshot at the begining of each new block. When overridding this
* function, be careful about the monotonicity of its result. Non-monotonic snapshot ids will break the contract.
*
* Implementing snapshots for every block using this method will incur significant gas costs. For a gas-efficient
* alternative consider {ERC20Votes}.
*
* ==== Gas Costs
*
* Snapshots are efficient. Snapshot creation is _O(1)_. Retrieval of balances or total supply from a snapshot is _O(log
* n)_ in the number of snapshots that have been created, although _n_ for a specific account will generally be much
* smaller since identical balances in subsequent snapshots are stored as a single entry.
*
* There is a constant overhead for normal ERC20 transfers due to the additional snapshot bookkeeping. This overhead is
* only significant for the first transfer that immediately follows a snapshot for a particular account. Subsequent
* transfers will have normal cost until the next snapshot, and so on.
*/
abstract contract ERC20Snapshot is MyobuBase {
// Inspired by Jordi Baylina's MiniMeToken to record historical balances:
// https://github.com/Giveth/minimd/blob/ea04d950eea153a04c51fa510b068b9dded390cb/contracts/MiniMeToken.sol
using Arrays for uint256[];
using Counters for Counters.Counter;
// Snapshotted values have arrays of ids and the value corresponding to that id. These could be an array of a
// Snapshot struct, but that would impede usage of functions that work on an array.
struct Snapshots {
uint256[] ids;
uint256[] values;
}
mapping(address => Snapshots) private _accountBalanceSnapshots;
Snapshots private _totalSupplySnapshots;
// Snapshot ids increase monotonically, with the first value being 1. An id of 0 is invalid.
Counters.Counter private _currentSnapshotId;
/**
* @dev Emitted by {_snapshot} when a snapshot identified by `id` is created.
*/
event Snapshot(uint256 id);
/**
* @dev Creates a new snapshot and returns its snapshot id.
*
* Emits a {Snapshot} event that contains the same id.
*
* {_snapshot} is `internal` and you have to decide how to expose it externally. Its usage may be restricted to a
* set of accounts, for example using {AccessControl}, or it may be open to the public.
*
* [WARNING]
* ====
* While an open way of calling {_snapshot} is required for certain trust minimization mechanisms such as forking,
* you must consider that it can potentially be used by attackers in two ways.
*
* First, it can be used to increase the cost of retrieval of values from snapshots, although it will grow
* logarithmically thus rendering this attack ineffective in the long term. Second, it can be used to target
* specific accounts and increase the cost of ERC20 transfers for them, in the ways specified in the Gas Costs
* section above.
*
* We haven't measured the actual numbers; if this is something you're interested in please reach out to us.
* ====
*/
function _snapshot() internal virtual returns (uint256) {
_currentSnapshotId.increment();
uint256 currentId = getCurrentSnapshotId();
emit Snapshot(currentId);
return currentId;
}
/**
* @dev Get the current snapshotId
*/
function getCurrentSnapshotId() public view virtual returns (uint256) {
return _currentSnapshotId.current();
}
/**
* @dev Retrieves the balance of `account` at the time `snapshotId` was created.
*/
function balanceOfAt(address account, uint256 snapshotId)
public
view
virtual
returns (uint256)
{
(bool snapshotted, uint256 value) = _valueAt(
snapshotId,
_accountBalanceSnapshots[account]
);
return snapshotted ? value : balanceOf(account);
}
/**
* @dev Retrieves the total supply at the time `snapshotId` was created.
*/
function totalSupplyAt(uint256 snapshotId)
public
view
virtual
returns (uint256)
{
(bool snapshotted, uint256 value) = _valueAt(
snapshotId,
_totalSupplySnapshots
);
return snapshotted ? value : totalSupply();
}
// Update balance and/or total supply snapshots before the values are modified. This is implemented
// in the _beforeTokenTransfer hook, which is executed for _mint, _burn, and _transfer operations.
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual override {
super._beforeTokenTransfer(from, to, amount);
if (from == address(0)) {
// mint
_updateAccountSnapshot(to);
_updateTotalSupplySnapshot();
} else if (to == address(0)) {
// burn
_updateAccountSnapshot(from);
_updateTotalSupplySnapshot();
} else {
// transfer
_updateAccountSnapshot(from);
_updateAccountSnapshot(to);
}
}
function _valueAt(uint256 snapshotId, Snapshots storage snapshots)
private
view
returns (bool, uint256)
{
require(snapshotId > 0, "ERC20Snapshot: id is 0");
require(
snapshotId <= getCurrentSnapshotId(),
"ERC20Snapshot: nonexistent id"
);
// When a valid snapshot is queried, there are three possibilities:
// a) The queried value was not modified after the snapshot was taken. Therefore, a snapshot entry was never
// created for this id, and all stored snapshot ids are smaller than the requested one. The value that corresponds
// to this id is the current one.
// b) The queried value was modified after the snapshot was taken. Therefore, there will be an entry with the
// requested id, and its value is the one to return.
// c) More snapshots were created after the requested one, and the queried value was later modified. There will be
// no entry for the requested id: the value that corresponds to it is that of the smallest snapshot id that is
// larger than the requested one.
//
// In summary, we need to find an element in an array, returning the index of the smallest value that is larger if
// it is not found, unless said value doesn't exist (e.g. when all values are smaller). Arrays.findUpperBound does
// exactly this.
uint256 index = snapshots.ids.findUpperBound(snapshotId);
if (index == snapshots.ids.length) {
return (false, 0);
} else {
return (true, snapshots.values[index]);
}
}
function _updateAccountSnapshot(address account) private {
_updateSnapshot(_accountBalanceSnapshots[account], balanceOf(account));
}
function _updateTotalSupplySnapshot() private {
_updateSnapshot(_totalSupplySnapshots, totalSupply());
}
function _updateSnapshot(Snapshots storage snapshots, uint256 currentValue)
private
{
uint256 currentId = getCurrentSnapshotId();
if (_lastSnapshotId(snapshots.ids) < currentId) {
snapshots.ids.push(currentId);
snapshots.values.push(currentValue);
}
}
function _lastSnapshotId(uint256[] storage ids)
private
view
returns (uint256)
{
if (ids.length == 0) {
return 0;
} else {
return ids[ids.length - 1];
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./ERC20.sol";
import "./Utils/MyobuLib.sol";
import "./Utils/Ownable.sol";
import "./Interfaces/IUniswapV2Router.sol";
import "./Interfaces/IUniswapV2Factory.sol";
import "./Interfaces/IUniswapV2Pair.sol";
import "./Interfaces/IMyobu.sol";
abstract contract MyobuBase is IMyobu, Ownable, ERC20 {
uint256 internal constant MAX = type(uint256).max;
uint256 private constant SUPPLY = 1000000000000 * 10**9;
string internal constant NAME = unicode"Myōbu";
string internal constant SYMBOL = "MYOBU";
uint8 internal constant DECIMALS = 9;
// pair => router
mapping(address => address) internal _routerFor;
mapping(address => bool) private taxedTransfer;
Fees private fees;
address payable internal _taxAddress;
IUniswapV2Router internal uniswapV2Router;
address internal uniswapV2Pair;
bool private tradingOpen;
bool private liquidityAdded;
bool private inSwap;
bool private swapEnabled;
modifier lockTheSwap() {
inSwap = true;
_;
inSwap = false;
}
constructor(address payable addr1) ERC20(NAME, SYMBOL) {
_taxAddress = addr1;
_mint(_msgSender(), SUPPLY);
}
function decimals() public pure virtual override returns (uint8) {
return DECIMALS;
}
function taxedPair(address pair)
public
view
virtual
override
returns (bool)
{
return _routerFor[pair] != address(0);
}
// Transfer tokens without emmiting events from an address to this address, used for taking fees
function transferFee(address from, uint256 amount) internal {
_balances[from] -= amount;
_balances[address(this)] += amount;
}
function takeFee(
address from,
uint256 amount,
uint256 teamFee
) internal returns (uint256) {
if (teamFee == 0) return 0;
uint256 tTeam = MyobuLib.percentageOf(amount, teamFee);
transferFee(from, tTeam);
emit FeesTaken(tTeam);
return tTeam;
}
function _transfer(
address from,
address to,
uint256 amount
) internal virtual override {
// If no fee, it is 0 which will take no fee
uint256 _teamFee;
if (from != owner() && to != owner()) {
if (swapEnabled && !inSwap) {
if (taxedPair(from) && !taxedPair(to)) {
require(tradingOpen);
_teamFee = fees.buyFee;
} else if (taxedTransfer[from] || taxedTransfer[to]) {
_teamFee = fees.transferFee;
} else if (taxedPair(to)) {
require(tradingOpen);
require(amount <= (balanceOf(to) * fees.impact) / 100);
swapTokensForEth(balanceOf(address(this)));
sendETHToFee(address(this).balance);
_teamFee = fees.sellFee;
}
}
}
uint256 fee = takeFee(from, amount, _teamFee);
super._transfer(from, to, amount - fee);
}
function swapTokensForEth(uint256 tokenAmount) internal lockTheSwap {
MyobuLib.swapForETH(uniswapV2Router, tokenAmount, address(this));
}
function sendETHToFee(uint256 amount) internal {
_taxAddress.transfer(amount);
}
function openTrading() external virtual onlyOwner {
require(liquidityAdded);
tradingOpen = true;
}
function addDEX(address pair, address router) public virtual onlyOwner {
require(!taxedPair(pair), "DEX already exists");
address tokenFor = MyobuLib.tokenFor(pair);
_routerFor[pair] = router;
_approve(address(this), router, MAX);
IERC20(tokenFor).approve(router, MAX);
IERC20(pair).approve(router, MAX);
}
function removeDEX(address pair) external virtual onlyOwner {
require(taxedPair(pair), "DEX does not exist");
address tokenFor = MyobuLib.tokenFor(pair);
address router = _routerFor[pair];
delete _routerFor[pair];
_approve(address(this), router, 0);
IERC20(tokenFor).approve(router, 0);
IERC20(pair).approve(router, 0);
}
function addLiquidity() external virtual onlyOwner lockTheSwap {
IUniswapV2Router _uniswapV2Router = IUniswapV2Router(
0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
);
uniswapV2Router = _uniswapV2Router;
uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
.createPair(address(this), _uniswapV2Router.WETH());
addDEX(uniswapV2Pair, address(_uniswapV2Router));
MyobuLib.addLiquidityETH(
uniswapV2Router,
balanceOf(address(this)),
address(this).balance,
owner()
);
liquidityAdded = true;
}
function setTaxAddress(address payable newTaxAddress) external onlyOwner {
_taxAddress = newTaxAddress;
emit TaxAddressChanged(newTaxAddress);
}
function setTaxedTransferFor(address[] calldata taxedTransfer_)
external
virtual
onlyOwner
{
for (uint256 i; i < taxedTransfer_.length; i++) {
taxedTransfer[taxedTransfer_[i]] = true;
}
emit TaxedTransferAddedFor(taxedTransfer_);
}
function removeTaxedTransferFor(address[] calldata notTaxed)
external
virtual
onlyOwner
{
for (uint256 i; i < notTaxed.length; i++) {
taxedTransfer[notTaxed[i]] = false;
}
emit TaxedTransferRemovedFor(notTaxed);
}
function manualswap() external onlyOwner {
swapTokensForEth(balanceOf(address(this)));
}
function manualsend() external onlyOwner {
sendETHToFee(address(this).balance);
}
function setSwapRouter(IUniswapV2Router newRouter) external onlyOwner {
require(liquidityAdded, "Add liquidity before doing this");
address weth = uniswapV2Router.WETH();
address newPair = IUniswapV2Factory(newRouter.factory()).getPair(
address(this),
weth
);
require(
newPair != address(0),
"WETH Pair does not exist for that router"
);
require(taxedPair(newPair), "The pair must be a taxed pair");
(uint256 reservesOld, , ) = IUniswapV2Pair(uniswapV2Pair).getReserves();
(uint256 reservesNew, , ) = IUniswapV2Pair(newPair).getReserves();
require(
reservesNew > reservesOld,
"New pair must have more WETH Reserves"
);
uniswapV2Router = newRouter;
uniswapV2Pair = newPair;
}
function setFees(Fees memory newFees) public onlyOwner {
require(
newFees.impact != 0 && newFees.impact <= 100,
"Impact must be greater than 0 and under or equal to 100"
);
require(
newFees.buyFee < 15 &&
newFees.sellFee < 15 &&
newFees.transferFee <= newFees.sellFee,
"Fees for a buy / sell must be under 15"
);
fees = newFees;
if (newFees.buyFee + newFees.sellFee == 0) {
swapEnabled = false;
} else {
swapEnabled = true;
}
emit FeesChanged(newFees);
}
function currentFees() external view override returns (Fees memory) {
return fees;
}
// solhint-disable-next-line
receive() external payable virtual {}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
*/
library Counters {
struct Counter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to
// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
// this feature: see https://github.com/ethereum/solidity/issues/4637
uint256 _value; // default: 0
}
function current(Counter storage counter) internal view returns (uint256) {
return counter._value;
}
function increment(Counter storage counter) internal {
unchecked {
counter._value += 1;
}
}
function decrement(Counter storage counter) internal {
uint256 value = counter._value;
require(value > 0, "Counter: decrement overflow");
unchecked {
counter._value = value - 1;
}
}
function reset(Counter storage counter) internal {
counter._value = 0;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./Math.sol";
/**
* @dev Collection of functions related to array types.
*/
library Arrays {
/**
* @dev Searches a sorted `array` and returns the first index that contains
* a value greater or equal to `element`. If no such index exists (i.e. all
* values in the array are strictly less than `element`), the array length is
* returned. Time complexity O(log n).
*
* `array` is expected to be sorted in ascending order, and to contain no
* repeated elements.
*/
function findUpperBound(uint256[] storage array, uint256 element)
internal
view
returns (uint256)
{
if (array.length == 0) {
return 0;
}
uint256 low = 0;
uint256 high = array.length;
while (low < high) {
uint256 mid = Math.average(low, high);
// Note that mid will always be strictly less than high (i.e. it will be a valid array index)
// because Math.average rounds down (it does integer division with truncation).
if (array[mid] > element) {
high = mid;
} else {
low = mid + 1;
}
}
// At this point `low` is the exclusive upper bound. We will return the inclusive upper bound.
if (low > 0 && array[low - 1] == element) {
return low - 1;
} else {
return low;
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a >= b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b) / 2 can overflow.
return (a & b) + (a ^ b) / 2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds up instead
* of rounding down.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.
return a / b + (a % b == 0 ? 0 : 1);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC20.sol";
interface IMyobu is IERC20 {
event DAOChanged(address newDAOContract);
event MyobuSwapChanged(address newMyobuSwap);
function DAO() external view returns (address); // solhint-disable-line
function myobuSwap() external view returns (address);
event TaxAddressChanged(address newTaxAddress);
event TaxedTransferAddedFor(address[] addresses);
event TaxedTransferRemovedFor(address[] addresses);
event FeesTaken(uint256 teamFee);
event FeesChanged(Fees newFees);
struct Fees {
uint256 impact;
uint256 buyFee;
uint256 sellFee;
uint256 transferFee;
}
function currentFees() external view returns (Fees memory);
struct LiquidityETHParams {
address pair;
address to;
uint256 amountTokenOrLP;
uint256 amountTokenMin;
uint256 amountETHMin;
uint256 deadline;
}
event LiquidityAddedETH(
address pair,
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
);
function noFeeAddLiquidityETH(LiquidityETHParams calldata params)
external
payable
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
);
event LiquidityRemovedETH(
address pair,
uint256 amountToken,
uint256 amountETH,
uint256 amountRemoved
);
function noFeeRemoveLiquidityETH(LiquidityETHParams calldata params)
external
returns (uint256 amountToken, uint256 amountETH);
struct AddLiquidityParams {
address pair;
address to;
uint256 amountToken;
uint256 amountTokenB;
uint256 amountTokenMin;
uint256 amountTokenBMin;
uint256 deadline;
}
event LiquidityAdded(
address pair,
uint256 amountMyobu,
uint256 amountToken,
uint256 liquidity
);
function noFeeAddLiquidity(AddLiquidityParams calldata params)
external
returns (
uint256 amountMyobu,
uint256 amountToken,
uint256 liquidity
);
struct RemoveLiquidityParams {
address pair;
address to;
uint256 amountLP;
uint256 amountTokenMin;
uint256 amountTokenBMin;
uint256 deadline;
}
event LiquidityRemoved(
address pair,
uint256 amountMyobu,
uint256 amountToken,
uint256 liquidity
);
function noFeeRemoveLiquidity(RemoveLiquidityParams calldata params)
external
returns (uint256 amountMyobu, uint256 amountToken);
function taxedPair(address pair) external view returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IUniswapV2Pair {
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
event Transfer(address indexed from, address indexed to, uint256 value);
function name() external pure returns (string memory);
function symbol() external pure returns (string memory);
function decimals() external pure returns (uint8);
function totalSupply() external view returns (uint256);
function balanceOf(address owner) external view returns (uint256);
function allowance(address owner, address spender)
external
view
returns (uint256);
function approve(address spender, uint256 value) external returns (bool);
function transfer(address to, uint256 value) external returns (bool);
function transferFrom(
address from,
address to,
uint256 value
) external returns (bool);
function DOMAIN_SEPARATOR() external view returns (bytes32);
function PERMIT_TYPEHASH() external pure returns (bytes32);
function nonces(address owner) external view returns (uint256);
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
event Mint(address indexed sender, uint256 amount0, uint256 amount1);
event Burn(
address indexed sender,
uint256 amount0,
uint256 amount1,
address indexed to
);
event Swap(
address indexed sender,
uint256 amount0In,
uint256 amount1In,
uint256 amount0Out,
uint256 amount1Out,
address indexed to
);
event Sync(uint112 reserve0, uint112 reserve1);
function MINIMUM_LIQUIDITY() external pure returns (uint256);
function factory() external view returns (address);
function token0() external view returns (address);
function token1() external view returns (address);
function getReserves()
external
view
returns (
uint112 reserve0,
uint112 reserve1,
uint32 blockTimestampLast
);
function price0CumulativeLast() external view returns (uint256);
function price1CumulativeLast() external view returns (uint256);
function kLast() external view returns (uint256);
function mint(address to) external returns (uint256 liquidity);
function burn(address to)
external
returns (uint256 amount0, uint256 amount1);
function swap(
uint256 amount0Out,
uint256 amount1Out,
address to,
bytes calldata data
) external;
function skim(address to) external;
function sync() external;
function initialize(address, address) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IUniswapV2Factory {
function createPair(address tokenA, address tokenB)
external
returns (address pair);
function getPair(address tokenA, address tokenB)
external
view
returns (address pair);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IUniswapV2Router01 {
function factory() external pure returns (address);
// solhint-disable-next-line
function WETH() external pure returns (address);
function addLiquidity(
address tokenA,
address tokenB,
uint256 amountADesired,
uint256 amountBDesired,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
)
external
returns (
uint256 amountA,
uint256 amountB,
uint256 liquidity
);
function addLiquidityETH(
address token,
uint256 amountTokenDesired,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
)
external
payable
returns (
uint256 amountToken,
uint256 amountETH,
uint256 liquidity
);
function removeLiquidity(
address tokenA,
address tokenB,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline
) external returns (uint256 amountA, uint256 amountB);
function removeLiquidityETH(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) external returns (uint256 amountToken, uint256 amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint256 liquidity,
uint256 amountAMin,
uint256 amountBMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountA, uint256 amountB);
function removeLiquidityETHWithPermit(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountToken, uint256 amountETH);
function swapExactTokensForTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapTokensForExactTokens(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapExactETHForTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable returns (uint256[] memory amounts);
function swapTokensForExactETH(
uint256 amountOut,
uint256 amountInMax,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapExactTokensForETH(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external returns (uint256[] memory amounts);
function swapETHForExactTokens(
uint256 amountOut,
address[] calldata path,
address to,
uint256 deadline
) external payable returns (uint256[] memory amounts);
function quote(
uint256 amountA,
uint256 reserveA,
uint256 reserveB
) external pure returns (uint256 amountB);
function getAmountOut(
uint256 amountIn,
uint256 reserveIn,
uint256 reserveOut
) external pure returns (uint256 amountOut);
function getAmountIn(
uint256 amountOut,
uint256 reserveIn,
uint256 reserveOut
) external pure returns (uint256 amountIn);
function getAmountsOut(uint256 amountIn, address[] calldata path)
external
view
returns (uint256[] memory amounts);
function getAmountsIn(uint256 amountOut, address[] calldata path)
external
view
returns (uint256[] memory amounts);
}
interface IUniswapV2Router is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline
) external returns (uint256 amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint256 liquidity,
uint256 amountTokenMin,
uint256 amountETHMin,
address to,
uint256 deadline,
bool approveMax,
uint8 v,
bytes32 r,
bytes32 s
) external returns (uint256 amountETH);
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint256 amountIn,
uint256 amountOutMin,
address[] calldata path,
address to,
uint256 deadline
) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(
address indexed previousOwner,
address indexed newOwner
);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_setOwner(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
_;
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() external virtual onlyOwner {
_setOwner(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) external virtual onlyOwner {
require(
newOwner != address(0),
"Ownable: new owner is the zero address"
);
_setOwner(newOwner);
}
function _setOwner(address newOwner) private {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "../Interfaces/IUniswapV2Router.sol";
import "../Interfaces/IUniswapV2Pair.sol";
import "../Interfaces/IERC20.sol";
library MyobuLib {
/**
* @dev Calculates the percentage of a number
* @param number: The number to calculate the percentage of
* @param percentage: The percentage of the number to return
* @return The percentage of a number
*/
function percentageOf(uint256 number, uint256 percentage)
internal
pure
returns (uint256)
{
return (number * percentage) / 100;
}
/**
* @dev Swaps an amount of tokens for ETH
* @param uniswapV2Router: The uniswap router to trade through
* @param amount: The amount of tokens to swap
* @param to: The address to send the recieved tokens to
* @return The amount of ETH recieved
*/
function swapForETH(
IUniswapV2Router uniswapV2Router,
uint256 amount,
address to
) internal returns (uint256) {
uint256 startingBalance = to.balance;
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = uniswapV2Router.WETH();
uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
amount,
0,
path,
to,
block.timestamp
);
return to.balance - startingBalance;
}
/**
* @dev Adds liquidity for the token in ETH
* @param uniswapV2Router: The uniswap router to add liquidity through
* @param amountToken: The amount of tokens to add liquidity with
* @param amountETH: The amount of ETH to add liquidity with
* @param to: The address to send the recieved LP tokens to
*/
function addLiquidityETH(
IUniswapV2Router uniswapV2Router,
uint256 amountToken,
uint256 amountETH,
address to
) internal {
uniswapV2Router.addLiquidityETH{value: amountETH}(
address(this),
amountToken,
0,
0,
to,
block.timestamp
);
}
/**
* @param token: The address of the token to transfer
* @param from: The sender of the tokens
* @param to: The receiver of the tokens
* @param amount: The amount of tokens to transfer
*/
function transferTokens(
address token,
address from,
address to,
uint256 amount
) internal {
IERC20(token).transferFrom(from, to, amount);
}
/**
* @dev Returns the token for a Uniswap V2 Pair
*/
function tokenFor(address pair) internal view returns (address) {
return IUniswapV2Pair(pair).token0();
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./Interfaces/IERC20.sol";
import "./Interfaces/IERC20Metadata.sol";
import "./Utils/Context.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20, IERC20Metadata {
mapping(address => uint256) internal _balances;
mapping(address => mapping(address => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* The default value of {decimals} is 18. To select a different value for
* {decimals} you should overload it.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the value {ERC20} uses, unless this function is
* overridden;
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual override returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account)
public
view
virtual
override
returns (uint256)
{
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount)
public
virtual
override
returns (bool)
{
_transfer(_msgSender(), recipient, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender)
public
view
virtual
override
returns (uint256)
{
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount)
public
virtual
override
returns (bool)
{
_approve(_msgSender(), spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* Requirements:
*
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
* - the caller must have allowance for ``sender``'s tokens of at least
* `amount`.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) public virtual override returns (bool) {
_transfer(sender, recipient, amount);
uint256 currentAllowance = _allowances[sender][_msgSender()];
require(
currentAllowance >= amount,
"ERC20: transfer amount exceeds allowance"
);
unchecked {
_approve(sender, _msgSender(), currentAllowance - amount);
}
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue)
public
virtual
returns (bool)
{
_approve(
_msgSender(),
spender,
_allowances[_msgSender()][spender] + addedValue
);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue)
public
virtual
returns (bool)
{
uint256 currentAllowance = _allowances[_msgSender()][spender];
require(
currentAllowance >= subtractedValue,
"ERC20: decreased allowance below zero"
);
unchecked {
_approve(_msgSender(), spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `amount` of tokens from `sender` to `recipient`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(
address sender,
address recipient,
uint256 amount
) internal virtual {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(sender, recipient, amount);
uint256 senderBalance = _balances[sender];
require(
senderBalance >= amount,
"ERC20: transfer amount exceeds balance"
);
unchecked {
_balances[sender] = senderBalance - amount;
}
_balances[recipient] += amount;
emit Transfer(sender, recipient, amount);
_afterTokenTransfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
_balances[account] += amount;
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
}
_totalSupply -= amount;
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*/
function _approve(
address owner,
address spender,
uint256 amount
) internal virtual {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {} // solhint-disable-line
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/
function _afterTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual {} // solhint-disable-line
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address recipient, uint256 amount)
external
returns (bool);
function allowance(address owner, address spender)
external
view
returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(
address sender,
address recipient,
uint256 amount
) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(
address indexed owner,
address indexed spender,
uint256 value
);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
