Transaction Hash:
Block:
16225385 at Dec-20-2022 10:43:23 AM +UTC
Transaction Fee:
0.001105772460581817 ETH
$2.41
Gas Used:
83,867 Gas / 13.184833851 Gwei
Emitted Events:
134 |
Token.Transfer( from=[Receiver] Claim, to=Token, value=0 )
|
135 |
Token.Transfer( from=[Receiver] Claim, to=[Sender] 0x0bfc4fd20d520f2e6302b14f6d06168703332c7d, value=61161696147064006000000 )
|
Account State Difference:
Address | Before | After | State Difference | ||
---|---|---|---|---|---|
0x0Bfc4Fd2...703332c7d |
0.004277054251760334 Eth
Nonce: 8
|
0.003171281791178517 Eth
Nonce: 9
| 0.001105772460581817 | ||
0x3C3207B8...5D8dcb96C | |||||
0x690B9A9E...Db4FaC990
Miner
| (builder0x69) | 1.979128872016273728 Eth | 1.979254672516273728 Eth | 0.0001258005 | |
0xFBCDC220...1AC6227f8 |
Execution Trace
Claim.CALL( )
-
Token.transfer( to=0x0Bfc4Fd20d520f2e6302B14F6d06168703332c7d, amount=61161696147064006000000 ) => ( True )
File 1 of 2: Claim
File 2 of 2: Token
// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol) pragma solidity ^0.8.0; import "../utils/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() { _transferOwnership(_msgSender()); } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { _checkOwner(); _; } /** * @dev Returns the address of the current owner. */ function owner() public view virtual returns (address) { return _owner; } /** * @dev Throws if the sender is not the owner. */ function _checkOwner() internal view virtual { 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() public virtual onlyOwner { _transferOwnership(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) public virtual onlyOwner { require(newOwner != address(0), "Ownable: new owner is the zero address"); _transferOwnership(newOwner); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Internal function without access restriction. */ function _transferOwnership(address newOwner) internal virtual { address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612]. * * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't * need to send a transaction, and thus is not required to hold Ether at all. */ interface IERC20Permit { /** * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens, * given ``owner``'s signed approval. * * IMPORTANT: The same issues {IERC20-approve} has related to transaction * ordering also apply here. * * Emits an {Approval} event. * * Requirements: * * - `spender` cannot be the zero address. * - `deadline` must be a timestamp in the future. * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner` * over the EIP712-formatted function arguments. * - the signature must use ``owner``'s current nonce (see {nonces}). * * For more information on the signature format, see the * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP * section]. */ function permit( address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) external; /** * @dev Returns the current nonce for `owner`. This value must be * included whenever a signature is generated for {permit}. * * Every successful call to {permit} increases ``owner``'s nonce by one. This * prevents a signature from being used multiple times. */ function nonces(address owner) external view returns (uint256); /** * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}. */ // solhint-disable-next-line func-name-mixedcase function DOMAIN_SEPARATOR() external view returns (bytes32); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC20 standard as defined in the EIP. */ interface IERC20 { /** * @dev Emitted when `value` tokens are moved from one account (`from`) to * another (`to`). * * Note that `value` may be zero. */ event Transfer(address indexed from, address indexed to, uint256 value); /** * @dev Emitted when the allowance of a `spender` for an `owner` is set by * a call to {approve}. `value` is the new allowance. */ event Approval(address indexed owner, address indexed spender, uint256 value); /** * @dev Returns the amount of tokens in existence. */ function totalSupply() external view returns (uint256); /** * @dev Returns the amount of tokens owned by `account`. */ function balanceOf(address account) external view returns (uint256); /** * @dev Moves `amount` tokens from the caller's account to `to`. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transfer(address to, uint256 amount) external returns (bool); /** * @dev Returns the remaining number of tokens that `spender` will be * allowed to spend on behalf of `owner` through {transferFrom}. This is * zero by default. * * This value changes when {approve} or {transferFrom} are called. */ function allowance(address owner, address spender) external view returns (uint256); /** * @dev Sets `amount` as the allowance of `spender` over the caller's tokens. * * Returns a boolean value indicating whether the operation succeeded. * * IMPORTANT: 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 * * Emits an {Approval} event. */ function approve(address spender, uint256 amount) external returns (bool); /** * @dev Moves `amount` tokens from `from` to `to` using the * allowance mechanism. `amount` is then deducted from the caller's * allowance. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transferFrom( address from, address to, uint256 amount ) external returns (bool); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol) pragma solidity ^0.8.0; import "../IERC20.sol"; import "../extensions/draft-IERC20Permit.sol"; import "../../../utils/Address.sol"; /** * @title SafeERC20 * @dev Wrappers around ERC20 operations that throw on failure (when the token * contract returns false). Tokens that return no value (and instead revert or * throw on failure) are also supported, non-reverting calls are assumed to be * successful. * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract, * which allows you to call the safe operations as `token.safeTransfer(...)`, etc. */ library SafeERC20 { using Address for address; function safeTransfer( IERC20 token, address to, uint256 value ) internal { _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value)); } function safeTransferFrom( IERC20 token, address from, address to, uint256 value ) internal { _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value)); } /** * @dev Deprecated. This function has issues similar to the ones found in * {IERC20-approve}, and its usage is discouraged. * * Whenever possible, use {safeIncreaseAllowance} and * {safeDecreaseAllowance} instead. */ function safeApprove( IERC20 token, address spender, uint256 value ) internal { // safeApprove should only be called when setting an initial allowance, // or when resetting it to zero. To increase and decrease it, use // 'safeIncreaseAllowance' and 'safeDecreaseAllowance' require( (value == 0) || (token.allowance(address(this), spender) == 0), "SafeERC20: approve from non-zero to non-zero allowance" ); _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value)); } function safeIncreaseAllowance( IERC20 token, address spender, uint256 value ) internal { uint256 newAllowance = token.allowance(address(this), spender) + value; _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance)); } function safeDecreaseAllowance( IERC20 token, address spender, uint256 value ) internal { unchecked { uint256 oldAllowance = token.allowance(address(this), spender); require(oldAllowance >= value, "SafeERC20: decreased allowance below zero"); uint256 newAllowance = oldAllowance - value; _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance)); } } function safePermit( IERC20Permit token, address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) internal { uint256 nonceBefore = token.nonces(owner); token.permit(owner, spender, value, deadline, v, r, s); uint256 nonceAfter = token.nonces(owner); require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed"); } /** * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement * on the return value: the return value is optional (but if data is returned, it must not be false). * @param token The token targeted by the call. * @param data The call data (encoded using abi.encode or one of its variants). */ function _callOptionalReturn(IERC20 token, bytes memory data) private { // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that // the target address contains contract code and also asserts for success in the low-level call. bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed"); if (returndata.length > 0) { // Return data is optional require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed"); } } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol) pragma solidity ^0.8.1; /** * @dev Collection of functions related to the address type */ library Address { /** * @dev Returns true if `account` is a contract. * * [IMPORTANT] * ==== * It is unsafe to assume that an address for which this function returns * false is an externally-owned account (EOA) and not a contract. * * Among others, `isContract` will return false for the following * types of addresses: * * - an externally-owned account * - a contract in construction * - an address where a contract will be created * - an address where a contract lived, but was destroyed * ==== * * [IMPORTANT] * ==== * You shouldn't rely on `isContract` to protect against flash loan attacks! * * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract * constructor. * ==== */ function isContract(address account) internal view returns (bool) { // This method relies on extcodesize/address.code.length, which returns 0 // for contracts in construction, since the code is only stored at the end // of the constructor execution. return account.code.length > 0; } /** * @dev Replacement for Solidity's `transfer`: sends `amount` wei to * `recipient`, forwarding all available gas and reverting on errors. * * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost * of certain opcodes, possibly making contracts go over the 2300 gas limit * imposed by `transfer`, making them unable to receive funds via * `transfer`. {sendValue} removes this limitation. * * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more]. * * IMPORTANT: because control is transferred to `recipient`, care must be * taken to not create reentrancy vulnerabilities. Consider using * {ReentrancyGuard} or the * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. */ function sendValue(address payable recipient, uint256 amount) internal { require(address(this).balance >= amount, "Address: insufficient balance"); (bool success, ) = recipient.call{value: amount}(""); require(success, "Address: unable to send value, recipient may have reverted"); } /** * @dev Performs a Solidity function call using a low level `call`. A * plain `call` is an unsafe replacement for a function call: use this * function instead. * * If `target` reverts with a revert reason, it is bubbled up by this * function (like regular Solidity function calls). * * Returns the raw returned data. To convert to the expected return value, * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`]. * * Requirements: * * - `target` must be a contract. * - calling `target` with `data` must not revert. * * _Available since v3.1._ */ function functionCall(address target, bytes memory data) internal returns (bytes memory) { return functionCall(target, data, "Address: low-level call failed"); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with * `errorMessage` as a fallback revert reason when `target` reverts. * * _Available since v3.1._ */ function functionCall( address target, bytes memory data, string memory errorMessage ) internal returns (bytes memory) { return functionCallWithValue(target, data, 0, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but also transferring `value` wei to `target`. * * Requirements: * * - the calling contract must have an ETH balance of at least `value`. * - the called Solidity function must be `payable`. * * _Available since v3.1._ */ function functionCallWithValue( address target, bytes memory data, uint256 value ) internal returns (bytes memory) { return functionCallWithValue(target, data, value, "Address: low-level call with value failed"); } /** * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but * with `errorMessage` as a fallback revert reason when `target` reverts. * * _Available since v3.1._ */ function functionCallWithValue( address target, bytes memory data, uint256 value, string memory errorMessage ) internal returns (bytes memory) { require(address(this).balance >= value, "Address: insufficient balance for call"); require(isContract(target), "Address: call to non-contract"); (bool success, bytes memory returndata) = target.call{value: value}(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a static call. * * _Available since v3.3._ */ function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) { return functionStaticCall(target, data, "Address: low-level static call failed"); } /** * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], * but performing a static call. * * _Available since v3.3._ */ function functionStaticCall( address target, bytes memory data, string memory errorMessage ) internal view returns (bytes memory) { require(isContract(target), "Address: static call to non-contract"); (bool success, bytes memory returndata) = target.staticcall(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a delegate call. * * _Available since v3.4._ */ function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) { return functionDelegateCall(target, data, "Address: low-level delegate call failed"); } /** * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`], * but performing a delegate call. * * _Available since v3.4._ */ function functionDelegateCall( address target, bytes memory data, string memory errorMessage ) internal returns (bytes memory) { require(isContract(target), "Address: delegate call to non-contract"); (bool success, bytes memory returndata) = target.delegatecall(data); return verifyCallResult(success, returndata, errorMessage); } /** * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the * revert reason using the provided one. * * _Available since v4.3._ */ function verifyCallResult( bool success, bytes memory returndata, string memory errorMessage ) internal pure returns (bytes memory) { if (success) { return returndata; } else { // Look for revert reason and bubble it up if present if (returndata.length > 0) { // The easiest way to bubble the revert reason is using memory via assembly /// @solidity memory-safe-assembly assembly { let returndata_size := mload(returndata) revert(add(32, returndata), returndata_size) } } else { revert(errorMessage); } } } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (utils/Context.sol) 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; import "@openzeppelin/contracts/access/Ownable.sol"; import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol"; import "@openzeppelin/contracts/token/ERC20/IERC20.sol"; contract Claim is Ownable { using SafeERC20 for IERC20; // IERC20 public burnToken; IERC20 public claimToken; uint public conversionRatio; // eg - 1e7 ymeme = 1000e18 nymeme -> conversionRatio = 100000 uint public burnDecimal; uint public claimDecimal; mapping (address => ClaimInfo) public claimInfo; struct ClaimInfo { uint amount; bool exists; } constructor(address _claimToken) { // burnToken = IERC20(_burnToken); claimToken = IERC20(_claimToken); burnDecimal = 9; claimDecimal = 18; } function claim() external { require(claimInfo[msg.sender].exists == true, "Claim: Already claimed or no claim"); claimInfo[msg.sender].exists = false; claimToken.safeTransfer(msg.sender, claimInfo[msg.sender].amount); } // function claim(uint256 amount) external { // burnToken.safeTransferFrom(msg.sender, address(this), amount); // uint256 claimAmount = _calcClaimAmount(amount); // claimToken.safeTransfer(msg.sender, claimAmount); // } // function _calcClaimAmount(uint _burnAmount) internal view returns (uint256) { // return _burnAmount * 10**claimDecimal * conversionRatio / (100 * 10**burnDecimal); // } function addWhitelistedUsers(address[] calldata _users, uint[] calldata _amounts) external onlyOwner { for (uint i = 0; i < _users.length; i++) { claimInfo[_users[i]] = ClaimInfo(_amounts[i], true); } } // function setBurnToken(address _burnToken) external onlyOwner { // burnToken = IERC20(_burnToken); // } function setClaimToken(address _claimToken) external onlyOwner { claimToken = IERC20(_claimToken); } // function setConversionRatio(uint _conversionRatio) external onlyOwner { // conversionRatio = _conversionRatio; // } function withdraw(address _token, uint _amount) external onlyOwner { IERC20(_token).safeTransfer(owner(), _amount); } }
File 2 of 2: Token
// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol) pragma solidity ^0.8.0; import "../utils/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() { _transferOwnership(_msgSender()); } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { _checkOwner(); _; } /** * @dev Returns the address of the current owner. */ function owner() public view virtual returns (address) { return _owner; } /** * @dev Throws if the sender is not the owner. */ function _checkOwner() internal view virtual { 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() public virtual onlyOwner { _transferOwnership(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) public virtual onlyOwner { require(newOwner != address(0), "Ownable: new owner is the zero address"); _transferOwnership(newOwner); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Internal function without access restriction. */ function _transferOwnership(address newOwner) internal virtual { address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.5.0) (governance/utils/IVotes.sol) pragma solidity ^0.8.0; /** * @dev Common interface for {ERC20Votes}, {ERC721Votes}, and other {Votes}-enabled contracts. * * _Available since v4.5._ */ interface IVotes { /** * @dev Emitted when an account changes their delegate. */ event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate); /** * @dev Emitted when a token transfer or delegate change results in changes to a delegate's number of votes. */ event DelegateVotesChanged(address indexed delegate, uint256 previousBalance, uint256 newBalance); /** * @dev Returns the current amount of votes that `account` has. */ function getVotes(address account) external view returns (uint256); /** * @dev Returns the amount of votes that `account` had at the end of a past block (`blockNumber`). */ function getPastVotes(address account, uint256 blockNumber) external view returns (uint256); /** * @dev Returns the total supply of votes available at the end of a past block (`blockNumber`). * * NOTE: This value is the sum of all available votes, which is not necessarily the sum of all delegated votes. * Votes that have not been delegated are still part of total supply, even though they would not participate in a * vote. */ function getPastTotalSupply(uint256 blockNumber) external view returns (uint256); /** * @dev Returns the delegate that `account` has chosen. */ function delegates(address account) external view returns (address); /** * @dev Delegates votes from the sender to `delegatee`. */ function delegate(address delegatee) external; /** * @dev Delegates votes from signer to `delegatee`. */ function delegateBySig( address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s ) external; } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/ERC20.sol) pragma solidity ^0.8.0; import "./IERC20.sol"; import "./extensions/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) private _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: * * - `to` cannot be the zero address. * - the caller must have a balance of at least `amount`. */ function transfer(address to, uint256 amount) public virtual override returns (bool) { address owner = _msgSender(); _transfer(owner, to, 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}. * * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on * `transferFrom`. This is semantically equivalent to an infinite approval. * * Requirements: * * - `spender` cannot be the zero address. */ function approve(address spender, uint256 amount) public virtual override returns (bool) { address owner = _msgSender(); _approve(owner, 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}. * * NOTE: Does not update the allowance if the current allowance * is the maximum `uint256`. * * Requirements: * * - `from` and `to` cannot be the zero address. * - `from` must have a balance of at least `amount`. * - the caller must have allowance for ``from``'s tokens of at least * `amount`. */ function transferFrom( address from, address to, uint256 amount ) public virtual override returns (bool) { address spender = _msgSender(); _spendAllowance(from, spender, amount); _transfer(from, to, amount); return true; } /** * @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) { address owner = _msgSender(); _approve(owner, spender, allowance(owner, 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) { address owner = _msgSender(); uint256 currentAllowance = allowance(owner, spender); require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero"); unchecked { _approve(owner, spender, currentAllowance - subtractedValue); } return true; } /** * @dev Moves `amount` of tokens from `from` to `to`. * * 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: * * - `from` cannot be the zero address. * - `to` cannot be the zero address. * - `from` must have a balance of at least `amount`. */ function _transfer( address from, address to, uint256 amount ) internal virtual { require(from != address(0), "ERC20: transfer from the zero address"); require(to != address(0), "ERC20: transfer to the zero address"); _beforeTokenTransfer(from, to, amount); uint256 fromBalance = _balances[from]; require(fromBalance >= amount, "ERC20: transfer amount exceeds balance"); unchecked { _balances[from] = fromBalance - amount; } _balances[to] += amount; emit Transfer(from, to, amount); _afterTokenTransfer(from, to, 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 Updates `owner` s allowance for `spender` based on spent `amount`. * * Does not update the allowance amount in case of infinite allowance. * Revert if not enough allowance is available. * * Might emit an {Approval} event. */ function _spendAllowance( address owner, address spender, uint256 amount ) internal virtual { uint256 currentAllowance = allowance(owner, spender); if (currentAllowance != type(uint256).max) { require(currentAllowance >= amount, "ERC20: insufficient allowance"); unchecked { _approve(owner, spender, currentAllowance - amount); } } } /** * @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 {} /** * @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 {} } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/extensions/draft-ERC20Permit.sol) pragma solidity ^0.8.0; import "./draft-IERC20Permit.sol"; import "../ERC20.sol"; import "../../../utils/cryptography/draft-EIP712.sol"; import "../../../utils/cryptography/ECDSA.sol"; import "../../../utils/Counters.sol"; /** * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612]. * * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't * need to send a transaction, and thus is not required to hold Ether at all. * * _Available since v3.4._ */ abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 { using Counters for Counters.Counter; mapping(address => Counters.Counter) private _nonces; // solhint-disable-next-line var-name-mixedcase bytes32 private constant _PERMIT_TYPEHASH = keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"); /** * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`. * However, to ensure consistency with the upgradeable transpiler, we will continue * to reserve a slot. * @custom:oz-renamed-from _PERMIT_TYPEHASH */ // solhint-disable-next-line var-name-mixedcase bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT; /** * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`. * * It's a good idea to use the same `name` that is defined as the ERC20 token name. */ constructor(string memory name) EIP712(name, "1") {} /** * @dev See {IERC20Permit-permit}. */ function permit( address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) public virtual override { require(block.timestamp <= deadline, "ERC20Permit: expired deadline"); bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline)); bytes32 hash = _hashTypedDataV4(structHash); address signer = ECDSA.recover(hash, v, r, s); require(signer == owner, "ERC20Permit: invalid signature"); _approve(owner, spender, value); } /** * @dev See {IERC20Permit-nonces}. */ function nonces(address owner) public view virtual override returns (uint256) { return _nonces[owner].current(); } /** * @dev See {IERC20Permit-DOMAIN_SEPARATOR}. */ // solhint-disable-next-line func-name-mixedcase function DOMAIN_SEPARATOR() external view override returns (bytes32) { return _domainSeparatorV4(); } /** * @dev "Consume a nonce": return the current value and increment. * * _Available since v4.1._ */ function _useNonce(address owner) internal virtual returns (uint256 current) { Counters.Counter storage nonce = _nonces[owner]; current = nonce.current(); nonce.increment(); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612]. * * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't * need to send a transaction, and thus is not required to hold Ether at all. */ interface IERC20Permit { /** * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens, * given ``owner``'s signed approval. * * IMPORTANT: The same issues {IERC20-approve} has related to transaction * ordering also apply here. * * Emits an {Approval} event. * * Requirements: * * - `spender` cannot be the zero address. * - `deadline` must be a timestamp in the future. * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner` * over the EIP712-formatted function arguments. * - the signature must use ``owner``'s current nonce (see {nonces}). * * For more information on the signature format, see the * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP * section]. */ function permit( address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) external; /** * @dev Returns the current nonce for `owner`. This value must be * included whenever a signature is generated for {permit}. * * Every successful call to {permit} increases ``owner``'s nonce by one. This * prevents a signature from being used multiple times. */ function nonces(address owner) external view returns (uint256); /** * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}. */ // solhint-disable-next-line func-name-mixedcase function DOMAIN_SEPARATOR() external view returns (bytes32); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Votes.sol) pragma solidity ^0.8.0; import "./draft-ERC20Permit.sol"; import "../../../utils/math/Math.sol"; import "../../../governance/utils/IVotes.sol"; import "../../../utils/math/SafeCast.sol"; import "../../../utils/cryptography/ECDSA.sol"; /** * @dev Extension of ERC20 to support Compound-like voting and delegation. This version is more generic than Compound's, * and supports token supply up to 2^224^ - 1, while COMP is limited to 2^96^ - 1. * * NOTE: If exact COMP compatibility is required, use the {ERC20VotesComp} variant of this module. * * This extension keeps a history (checkpoints) of each account's vote power. Vote power can be delegated either * by calling the {delegate} function directly, or by providing a signature to be used with {delegateBySig}. Voting * power can be queried through the public accessors {getVotes} and {getPastVotes}. * * By default, token balance does not account for voting power. This makes transfers cheaper. The downside is that it * requires users to delegate to themselves in order to activate checkpoints and have their voting power tracked. * * _Available since v4.2._ */ abstract contract ERC20Votes is IVotes, ERC20Permit { struct Checkpoint { uint32 fromBlock; uint224 votes; } bytes32 private constant _DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)"); mapping(address => address) private _delegates; mapping(address => Checkpoint[]) private _checkpoints; Checkpoint[] private _totalSupplyCheckpoints; /** * @dev Get the `pos`-th checkpoint for `account`. */ function checkpoints(address account, uint32 pos) public view virtual returns (Checkpoint memory) { return _checkpoints[account][pos]; } /** * @dev Get number of checkpoints for `account`. */ function numCheckpoints(address account) public view virtual returns (uint32) { return SafeCast.toUint32(_checkpoints[account].length); } /** * @dev Get the address `account` is currently delegating to. */ function delegates(address account) public view virtual override returns (address) { return _delegates[account]; } /** * @dev Gets the current votes balance for `account` */ function getVotes(address account) public view virtual override returns (uint256) { uint256 pos = _checkpoints[account].length; return pos == 0 ? 0 : _checkpoints[account][pos - 1].votes; } /** * @dev Retrieve the number of votes for `account` at the end of `blockNumber`. * * Requirements: * * - `blockNumber` must have been already mined */ function getPastVotes(address account, uint256 blockNumber) public view virtual override returns (uint256) { require(blockNumber < block.number, "ERC20Votes: block not yet mined"); return _checkpointsLookup(_checkpoints[account], blockNumber); } /** * @dev Retrieve the `totalSupply` at the end of `blockNumber`. Note, this value is the sum of all balances. * It is but NOT the sum of all the delegated votes! * * Requirements: * * - `blockNumber` must have been already mined */ function getPastTotalSupply(uint256 blockNumber) public view virtual override returns (uint256) { require(blockNumber < block.number, "ERC20Votes: block not yet mined"); return _checkpointsLookup(_totalSupplyCheckpoints, blockNumber); } /** * @dev Lookup a value in a list of (sorted) checkpoints. */ function _checkpointsLookup(Checkpoint[] storage ckpts, uint256 blockNumber) private view returns (uint256) { // We run a binary search to look for the earliest checkpoint taken after `blockNumber`. // // During the loop, the index of the wanted checkpoint remains in the range [low-1, high). // With each iteration, either `low` or `high` is moved towards the middle of the range to maintain the invariant. // - If the middle checkpoint is after `blockNumber`, we look in [low, mid) // - If the middle checkpoint is before or equal to `blockNumber`, we look in [mid+1, high) // Once we reach a single value (when low == high), we've found the right checkpoint at the index high-1, if not // out of bounds (in which case we're looking too far in the past and the result is 0). // Note that if the latest checkpoint available is exactly for `blockNumber`, we end up with an index that is // past the end of the array, so we technically don't find a checkpoint after `blockNumber`, but it works out // the same. uint256 high = ckpts.length; uint256 low = 0; while (low < high) { uint256 mid = Math.average(low, high); if (ckpts[mid].fromBlock > blockNumber) { high = mid; } else { low = mid + 1; } } return high == 0 ? 0 : ckpts[high - 1].votes; } /** * @dev Delegate votes from the sender to `delegatee`. */ function delegate(address delegatee) public virtual override { _delegate(_msgSender(), delegatee); } /** * @dev Delegates votes from signer to `delegatee` */ function delegateBySig( address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s ) public virtual override { require(block.timestamp <= expiry, "ERC20Votes: signature expired"); address signer = ECDSA.recover( _hashTypedDataV4(keccak256(abi.encode(_DELEGATION_TYPEHASH, delegatee, nonce, expiry))), v, r, s ); require(nonce == _useNonce(signer), "ERC20Votes: invalid nonce"); _delegate(signer, delegatee); } /** * @dev Maximum token supply. Defaults to `type(uint224).max` (2^224^ - 1). */ function _maxSupply() internal view virtual returns (uint224) { return type(uint224).max; } /** * @dev Snapshots the totalSupply after it has been increased. */ function _mint(address account, uint256 amount) internal virtual override { super._mint(account, amount); require(totalSupply() <= _maxSupply(), "ERC20Votes: total supply risks overflowing votes"); _writeCheckpoint(_totalSupplyCheckpoints, _add, amount); } /** * @dev Snapshots the totalSupply after it has been decreased. */ function _burn(address account, uint256 amount) internal virtual override { super._burn(account, amount); _writeCheckpoint(_totalSupplyCheckpoints, _subtract, amount); } /** * @dev Move voting power when tokens are transferred. * * Emits a {DelegateVotesChanged} event. */ function _afterTokenTransfer( address from, address to, uint256 amount ) internal virtual override { super._afterTokenTransfer(from, to, amount); _moveVotingPower(delegates(from), delegates(to), amount); } /** * @dev Change delegation for `delegator` to `delegatee`. * * Emits events {DelegateChanged} and {DelegateVotesChanged}. */ function _delegate(address delegator, address delegatee) internal virtual { address currentDelegate = delegates(delegator); uint256 delegatorBalance = balanceOf(delegator); _delegates[delegator] = delegatee; emit DelegateChanged(delegator, currentDelegate, delegatee); _moveVotingPower(currentDelegate, delegatee, delegatorBalance); } function _moveVotingPower( address src, address dst, uint256 amount ) private { if (src != dst && amount > 0) { if (src != address(0)) { (uint256 oldWeight, uint256 newWeight) = _writeCheckpoint(_checkpoints[src], _subtract, amount); emit DelegateVotesChanged(src, oldWeight, newWeight); } if (dst != address(0)) { (uint256 oldWeight, uint256 newWeight) = _writeCheckpoint(_checkpoints[dst], _add, amount); emit DelegateVotesChanged(dst, oldWeight, newWeight); } } } function _writeCheckpoint( Checkpoint[] storage ckpts, function(uint256, uint256) view returns (uint256) op, uint256 delta ) private returns (uint256 oldWeight, uint256 newWeight) { uint256 pos = ckpts.length; oldWeight = pos == 0 ? 0 : ckpts[pos - 1].votes; newWeight = op(oldWeight, delta); if (pos > 0 && ckpts[pos - 1].fromBlock == block.number) { ckpts[pos - 1].votes = SafeCast.toUint224(newWeight); } else { ckpts.push(Checkpoint({fromBlock: SafeCast.toUint32(block.number), votes: SafeCast.toUint224(newWeight)})); } } function _add(uint256 a, uint256 b) private pure returns (uint256) { return a + b; } function _subtract(uint256 a, uint256 b) private pure returns (uint256) { return a - b; } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20VotesComp.sol) pragma solidity ^0.8.0; import "./ERC20Votes.sol"; /** * @dev Extension of ERC20 to support Compound's voting and delegation. This version exactly matches Compound's * interface, with the drawback of only supporting supply up to (2^96^ - 1). * * NOTE: You should use this contract if you need exact compatibility with COMP (for example in order to use your token * with Governor Alpha or Bravo) and if you are sure the supply cap of 2^96^ is enough for you. Otherwise, use the * {ERC20Votes} variant of this module. * * This extension keeps a history (checkpoints) of each account's vote power. Vote power can be delegated either * by calling the {delegate} function directly, or by providing a signature to be used with {delegateBySig}. Voting * power can be queried through the public accessors {getCurrentVotes} and {getPriorVotes}. * * By default, token balance does not account for voting power. This makes transfers cheaper. The downside is that it * requires users to delegate to themselves in order to activate checkpoints and have their voting power tracked. * * _Available since v4.2._ */ abstract contract ERC20VotesComp is ERC20Votes { /** * @dev Comp version of the {getVotes} accessor, with `uint96` return type. */ function getCurrentVotes(address account) external view virtual returns (uint96) { return SafeCast.toUint96(getVotes(account)); } /** * @dev Comp version of the {getPastVotes} accessor, with `uint96` return type. */ function getPriorVotes(address account, uint256 blockNumber) external view virtual returns (uint96) { return SafeCast.toUint96(getPastVotes(account, blockNumber)); } /** * @dev Maximum token supply. Reduced to `type(uint96).max` (2^96^ - 1) to fit COMP interface. */ function _maxSupply() internal view virtual override returns (uint224) { return type(uint96).max; } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol) 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); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC20 standard as defined in the EIP. */ interface IERC20 { /** * @dev Emitted when `value` tokens are moved from one account (`from`) to * another (`to`). * * Note that `value` may be zero. */ event Transfer(address indexed from, address indexed to, uint256 value); /** * @dev Emitted when the allowance of a `spender` for an `owner` is set by * a call to {approve}. `value` is the new allowance. */ event Approval(address indexed owner, address indexed spender, uint256 value); /** * @dev Returns the amount of tokens in existence. */ function totalSupply() external view returns (uint256); /** * @dev Returns the amount of tokens owned by `account`. */ function balanceOf(address account) external view returns (uint256); /** * @dev Moves `amount` tokens from the caller's account to `to`. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transfer(address to, uint256 amount) external returns (bool); /** * @dev Returns the remaining number of tokens that `spender` will be * allowed to spend on behalf of `owner` through {transferFrom}. This is * zero by default. * * This value changes when {approve} or {transferFrom} are called. */ function allowance(address owner, address spender) external view returns (uint256); /** * @dev Sets `amount` as the allowance of `spender` over the caller's tokens. * * Returns a boolean value indicating whether the operation succeeded. * * IMPORTANT: 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 * * Emits an {Approval} event. */ function approve(address spender, uint256 amount) external returns (bool); /** * @dev Moves `amount` tokens from `from` to `to` using the * allowance mechanism. `amount` is then deducted from the caller's * allowance. * * Returns a boolean value indicating whether the operation succeeded. * * Emits a {Transfer} event. */ function transferFrom( address from, address to, uint256 amount ) external returns (bool); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts v4.4.1 (utils/Context.sol) 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 // OpenZeppelin Contracts v4.4.1 (utils/Counters.sol) 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 // OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol) pragma solidity ^0.8.0; import "./ECDSA.sol"; /** * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data. * * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible, * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding * they need in their contracts using a combination of `abi.encode` and `keccak256`. * * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA * ({_hashTypedDataV4}). * * The implementation of the domain separator was designed to be as efficient as possible while still properly updating * the chain id to protect against replay attacks on an eventual fork of the chain. * * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask]. * * _Available since v3.4._ */ abstract contract EIP712 { /* solhint-disable var-name-mixedcase */ // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to // invalidate the cached domain separator if the chain id changes. bytes32 private immutable _CACHED_DOMAIN_SEPARATOR; uint256 private immutable _CACHED_CHAIN_ID; address private immutable _CACHED_THIS; bytes32 private immutable _HASHED_NAME; bytes32 private immutable _HASHED_VERSION; bytes32 private immutable _TYPE_HASH; /* solhint-enable var-name-mixedcase */ /** * @dev Initializes the domain separator and parameter caches. * * The meaning of `name` and `version` is specified in * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]: * * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol. * - `version`: the current major version of the signing domain. * * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart * contract upgrade]. */ constructor(string memory name, string memory version) { bytes32 hashedName = keccak256(bytes(name)); bytes32 hashedVersion = keccak256(bytes(version)); bytes32 typeHash = keccak256( "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)" ); _HASHED_NAME = hashedName; _HASHED_VERSION = hashedVersion; _CACHED_CHAIN_ID = block.chainid; _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion); _CACHED_THIS = address(this); _TYPE_HASH = typeHash; } /** * @dev Returns the domain separator for the current chain. */ function _domainSeparatorV4() internal view returns (bytes32) { if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) { return _CACHED_DOMAIN_SEPARATOR; } else { return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION); } } function _buildDomainSeparator( bytes32 typeHash, bytes32 nameHash, bytes32 versionHash ) private view returns (bytes32) { return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this))); } /** * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this * function returns the hash of the fully encoded EIP712 message for this domain. * * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example: * * ```solidity * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode( * keccak256("Mail(address to,string contents)"), * mailTo, * keccak256(bytes(mailContents)) * ))); * address signer = ECDSA.recover(digest, signature); * ``` */ function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) { return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.3) (utils/cryptography/ECDSA.sol) pragma solidity ^0.8.0; import "../Strings.sol"; /** * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations. * * These functions can be used to verify that a message was signed by the holder * of the private keys of a given address. */ library ECDSA { enum RecoverError { NoError, InvalidSignature, InvalidSignatureLength, InvalidSignatureS, InvalidSignatureV } function _throwError(RecoverError error) private pure { if (error == RecoverError.NoError) { return; // no error: do nothing } else if (error == RecoverError.InvalidSignature) { revert("ECDSA: invalid signature"); } else if (error == RecoverError.InvalidSignatureLength) { revert("ECDSA: invalid signature length"); } else if (error == RecoverError.InvalidSignatureS) { revert("ECDSA: invalid signature 's' value"); } else if (error == RecoverError.InvalidSignatureV) { revert("ECDSA: invalid signature 'v' value"); } } /** * @dev Returns the address that signed a hashed message (`hash`) with * `signature` or error string. This address can then be used for verification purposes. * * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures: * this function rejects them by requiring the `s` value to be in the lower * half order, and the `v` value to be either 27 or 28. * * IMPORTANT: `hash` _must_ be the result of a hash operation for the * verification to be secure: it is possible to craft signatures that * recover to arbitrary addresses for non-hashed data. A safe way to ensure * this is by receiving a hash of the original message (which may otherwise * be too long), and then calling {toEthSignedMessageHash} on it. * * Documentation for signature generation: * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js] * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers] * * _Available since v4.3._ */ function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) { if (signature.length == 65) { bytes32 r; bytes32 s; uint8 v; // ecrecover takes the signature parameters, and the only way to get them // currently is to use assembly. /// @solidity memory-safe-assembly assembly { r := mload(add(signature, 0x20)) s := mload(add(signature, 0x40)) v := byte(0, mload(add(signature, 0x60))) } return tryRecover(hash, v, r, s); } else { return (address(0), RecoverError.InvalidSignatureLength); } } /** * @dev Returns the address that signed a hashed message (`hash`) with * `signature`. This address can then be used for verification purposes. * * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures: * this function rejects them by requiring the `s` value to be in the lower * half order, and the `v` value to be either 27 or 28. * * IMPORTANT: `hash` _must_ be the result of a hash operation for the * verification to be secure: it is possible to craft signatures that * recover to arbitrary addresses for non-hashed data. A safe way to ensure * this is by receiving a hash of the original message (which may otherwise * be too long), and then calling {toEthSignedMessageHash} on it. */ function recover(bytes32 hash, bytes memory signature) internal pure returns (address) { (address recovered, RecoverError error) = tryRecover(hash, signature); _throwError(error); return recovered; } /** * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately. * * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures] * * _Available since v4.3._ */ function tryRecover( bytes32 hash, bytes32 r, bytes32 vs ) internal pure returns (address, RecoverError) { bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff); uint8 v = uint8((uint256(vs) >> 255) + 27); return tryRecover(hash, v, r, s); } /** * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately. * * _Available since v4.2._ */ function recover( bytes32 hash, bytes32 r, bytes32 vs ) internal pure returns (address) { (address recovered, RecoverError error) = tryRecover(hash, r, vs); _throwError(error); return recovered; } /** * @dev Overload of {ECDSA-tryRecover} that receives the `v`, * `r` and `s` signature fields separately. * * _Available since v4.3._ */ function tryRecover( bytes32 hash, uint8 v, bytes32 r, bytes32 s ) internal pure returns (address, RecoverError) { // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most // signatures from current libraries generate a unique signature with an s-value in the lower half order. // // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept // these malleable signatures as well. if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) { return (address(0), RecoverError.InvalidSignatureS); } if (v != 27 && v != 28) { return (address(0), RecoverError.InvalidSignatureV); } // If the signature is valid (and not malleable), return the signer address address signer = ecrecover(hash, v, r, s); if (signer == address(0)) { return (address(0), RecoverError.InvalidSignature); } return (signer, RecoverError.NoError); } /** * @dev Overload of {ECDSA-recover} that receives the `v`, * `r` and `s` signature fields separately. */ function recover( bytes32 hash, uint8 v, bytes32 r, bytes32 s ) internal pure returns (address) { (address recovered, RecoverError error) = tryRecover(hash, v, r, s); _throwError(error); return recovered; } /** * @dev Returns an Ethereum Signed Message, created from a `hash`. This * produces hash corresponding to the one signed with the * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`] * JSON-RPC method as part of EIP-191. * * See {recover}. */ function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) { // 32 is the length in bytes of hash, // enforced by the type signature above return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\ 32", hash)); } /** * @dev Returns an Ethereum Signed Message, created from `s`. This * produces hash corresponding to the one signed with the * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`] * JSON-RPC method as part of EIP-191. * * See {recover}. */ function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) { return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\ ", Strings.toString(s.length), s)); } /** * @dev Returns an Ethereum Signed Typed Data, created from a * `domainSeparator` and a `structHash`. This produces hash corresponding * to the one signed with the * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`] * JSON-RPC method as part of EIP-712. * * See {recover}. */ function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) { return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash)); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (utils/math/Math.sol) pragma solidity ^0.8.0; /** * @dev Standard math utilities missing in the Solidity language. */ library Math { enum Rounding { Down, // Toward negative infinity Up, // Toward infinity Zero // Toward zero } /** * @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 == 0 ? 0 : (a - 1) / b + 1; } /** * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0 * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv) * with further edits by Uniswap Labs also under MIT license. */ function mulDiv( uint256 x, uint256 y, uint256 denominator ) internal pure returns (uint256 result) { unchecked { // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256 // variables such that product = prod1 * 2^256 + prod0. uint256 prod0; // Least significant 256 bits of the product uint256 prod1; // Most significant 256 bits of the product assembly { let mm := mulmod(x, y, not(0)) prod0 := mul(x, y) prod1 := sub(sub(mm, prod0), lt(mm, prod0)) } // Handle non-overflow cases, 256 by 256 division. if (prod1 == 0) { return prod0 / denominator; } // Make sure the result is less than 2^256. Also prevents denominator == 0. require(denominator > prod1); /////////////////////////////////////////////// // 512 by 256 division. /////////////////////////////////////////////// // Make division exact by subtracting the remainder from [prod1 prod0]. uint256 remainder; assembly { // Compute remainder using mulmod. remainder := mulmod(x, y, denominator) // Subtract 256 bit number from 512 bit number. prod1 := sub(prod1, gt(remainder, prod0)) prod0 := sub(prod0, remainder) } // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1. // See https://cs.stackexchange.com/q/138556/92363. // Does not overflow because the denominator cannot be zero at this stage in the function. uint256 twos = denominator & (~denominator + 1); assembly { // Divide denominator by twos. denominator := div(denominator, twos) // Divide [prod1 prod0] by twos. prod0 := div(prod0, twos) // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one. twos := add(div(sub(0, twos), twos), 1) } // Shift in bits from prod1 into prod0. prod0 |= prod1 * twos; // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for // four bits. That is, denominator * inv = 1 mod 2^4. uint256 inverse = (3 * denominator) ^ 2; // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works // in modular arithmetic, doubling the correct bits in each step. inverse *= 2 - denominator * inverse; // inverse mod 2^8 inverse *= 2 - denominator * inverse; // inverse mod 2^16 inverse *= 2 - denominator * inverse; // inverse mod 2^32 inverse *= 2 - denominator * inverse; // inverse mod 2^64 inverse *= 2 - denominator * inverse; // inverse mod 2^128 inverse *= 2 - denominator * inverse; // inverse mod 2^256 // Because the division is now exact we can divide by multiplying with the modular inverse of denominator. // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1 // is no longer required. result = prod0 * inverse; return result; } } /** * @notice Calculates x * y / denominator with full precision, following the selected rounding direction. */ function mulDiv( uint256 x, uint256 y, uint256 denominator, Rounding rounding ) internal pure returns (uint256) { uint256 result = mulDiv(x, y, denominator); if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) { result += 1; } return result; } /** * @dev Returns the square root of a number. It the number is not a perfect square, the value is rounded down. * * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11). */ function sqrt(uint256 a) internal pure returns (uint256) { if (a == 0) { return 0; } // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target. // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have // `msb(a) <= a < 2*msb(a)`. // We also know that `k`, the position of the most significant bit, is such that `msb(a) = 2**k`. // This gives `2**k < a <= 2**(k+1)` → `2**(k/2) <= sqrt(a) < 2 ** (k/2+1)`. // Using an algorithm similar to the msb conmputation, we are able to compute `result = 2**(k/2)` which is a // good first aproximation of `sqrt(a)` with at least 1 correct bit. uint256 result = 1; uint256 x = a; if (x >> 128 > 0) { x >>= 128; result <<= 64; } if (x >> 64 > 0) { x >>= 64; result <<= 32; } if (x >> 32 > 0) { x >>= 32; result <<= 16; } if (x >> 16 > 0) { x >>= 16; result <<= 8; } if (x >> 8 > 0) { x >>= 8; result <<= 4; } if (x >> 4 > 0) { x >>= 4; result <<= 2; } if (x >> 2 > 0) { result <<= 1; } // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128, // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision // into the expected uint128 result. unchecked { result = (result + a / result) >> 1; result = (result + a / result) >> 1; result = (result + a / result) >> 1; result = (result + a / result) >> 1; result = (result + a / result) >> 1; result = (result + a / result) >> 1; result = (result + a / result) >> 1; return min(result, a / result); } } /** * @notice Calculates sqrt(a), following the selected rounding direction. */ function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) { uint256 result = sqrt(a); if (rounding == Rounding.Up && result * result < a) { result += 1; } return result; } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (utils/math/SafeCast.sol) pragma solidity ^0.8.0; /** * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow * checks. * * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can * easily result in undesired exploitation or bugs, since developers usually * assume that overflows raise errors. `SafeCast` restores this intuition by * reverting the transaction when such an operation overflows. * * Using this library instead of the unchecked operations eliminates an entire * class of bugs, so it's recommended to use it always. * * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing * all math on `uint256` and `int256` and then downcasting. */ library SafeCast { /** * @dev Returns the downcasted uint248 from uint256, reverting on * overflow (when the input is greater than largest uint248). * * Counterpart to Solidity's `uint248` operator. * * Requirements: * * - input must fit into 248 bits * * _Available since v4.7._ */ function toUint248(uint256 value) internal pure returns (uint248) { require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits"); return uint248(value); } /** * @dev Returns the downcasted uint240 from uint256, reverting on * overflow (when the input is greater than largest uint240). * * Counterpart to Solidity's `uint240` operator. * * Requirements: * * - input must fit into 240 bits * * _Available since v4.7._ */ function toUint240(uint256 value) internal pure returns (uint240) { require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits"); return uint240(value); } /** * @dev Returns the downcasted uint232 from uint256, reverting on * overflow (when the input is greater than largest uint232). * * Counterpart to Solidity's `uint232` operator. * * Requirements: * * - input must fit into 232 bits * * _Available since v4.7._ */ function toUint232(uint256 value) internal pure returns (uint232) { require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits"); return uint232(value); } /** * @dev Returns the downcasted uint224 from uint256, reverting on * overflow (when the input is greater than largest uint224). * * Counterpart to Solidity's `uint224` operator. * * Requirements: * * - input must fit into 224 bits * * _Available since v4.2._ */ function toUint224(uint256 value) internal pure returns (uint224) { require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits"); return uint224(value); } /** * @dev Returns the downcasted uint216 from uint256, reverting on * overflow (when the input is greater than largest uint216). * * Counterpart to Solidity's `uint216` operator. * * Requirements: * * - input must fit into 216 bits * * _Available since v4.7._ */ function toUint216(uint256 value) internal pure returns (uint216) { require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits"); return uint216(value); } /** * @dev Returns the downcasted uint208 from uint256, reverting on * overflow (when the input is greater than largest uint208). * * Counterpart to Solidity's `uint208` operator. * * Requirements: * * - input must fit into 208 bits * * _Available since v4.7._ */ function toUint208(uint256 value) internal pure returns (uint208) { require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits"); return uint208(value); } /** * @dev Returns the downcasted uint200 from uint256, reverting on * overflow (when the input is greater than largest uint200). * * Counterpart to Solidity's `uint200` operator. * * Requirements: * * - input must fit into 200 bits * * _Available since v4.7._ */ function toUint200(uint256 value) internal pure returns (uint200) { require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits"); return uint200(value); } /** * @dev Returns the downcasted uint192 from uint256, reverting on * overflow (when the input is greater than largest uint192). * * Counterpart to Solidity's `uint192` operator. * * Requirements: * * - input must fit into 192 bits * * _Available since v4.7._ */ function toUint192(uint256 value) internal pure returns (uint192) { require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits"); return uint192(value); } /** * @dev Returns the downcasted uint184 from uint256, reverting on * overflow (when the input is greater than largest uint184). * * Counterpart to Solidity's `uint184` operator. * * Requirements: * * - input must fit into 184 bits * * _Available since v4.7._ */ function toUint184(uint256 value) internal pure returns (uint184) { require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits"); return uint184(value); } /** * @dev Returns the downcasted uint176 from uint256, reverting on * overflow (when the input is greater than largest uint176). * * Counterpart to Solidity's `uint176` operator. * * Requirements: * * - input must fit into 176 bits * * _Available since v4.7._ */ function toUint176(uint256 value) internal pure returns (uint176) { require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits"); return uint176(value); } /** * @dev Returns the downcasted uint168 from uint256, reverting on * overflow (when the input is greater than largest uint168). * * Counterpart to Solidity's `uint168` operator. * * Requirements: * * - input must fit into 168 bits * * _Available since v4.7._ */ function toUint168(uint256 value) internal pure returns (uint168) { require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits"); return uint168(value); } /** * @dev Returns the downcasted uint160 from uint256, reverting on * overflow (when the input is greater than largest uint160). * * Counterpart to Solidity's `uint160` operator. * * Requirements: * * - input must fit into 160 bits * * _Available since v4.7._ */ function toUint160(uint256 value) internal pure returns (uint160) { require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits"); return uint160(value); } /** * @dev Returns the downcasted uint152 from uint256, reverting on * overflow (when the input is greater than largest uint152). * * Counterpart to Solidity's `uint152` operator. * * Requirements: * * - input must fit into 152 bits * * _Available since v4.7._ */ function toUint152(uint256 value) internal pure returns (uint152) { require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits"); return uint152(value); } /** * @dev Returns the downcasted uint144 from uint256, reverting on * overflow (when the input is greater than largest uint144). * * Counterpart to Solidity's `uint144` operator. * * Requirements: * * - input must fit into 144 bits * * _Available since v4.7._ */ function toUint144(uint256 value) internal pure returns (uint144) { require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits"); return uint144(value); } /** * @dev Returns the downcasted uint136 from uint256, reverting on * overflow (when the input is greater than largest uint136). * * Counterpart to Solidity's `uint136` operator. * * Requirements: * * - input must fit into 136 bits * * _Available since v4.7._ */ function toUint136(uint256 value) internal pure returns (uint136) { require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits"); return uint136(value); } /** * @dev Returns the downcasted uint128 from uint256, reverting on * overflow (when the input is greater than largest uint128). * * Counterpart to Solidity's `uint128` operator. * * Requirements: * * - input must fit into 128 bits * * _Available since v2.5._ */ function toUint128(uint256 value) internal pure returns (uint128) { require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits"); return uint128(value); } /** * @dev Returns the downcasted uint120 from uint256, reverting on * overflow (when the input is greater than largest uint120). * * Counterpart to Solidity's `uint120` operator. * * Requirements: * * - input must fit into 120 bits * * _Available since v4.7._ */ function toUint120(uint256 value) internal pure returns (uint120) { require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits"); return uint120(value); } /** * @dev Returns the downcasted uint112 from uint256, reverting on * overflow (when the input is greater than largest uint112). * * Counterpart to Solidity's `uint112` operator. * * Requirements: * * - input must fit into 112 bits * * _Available since v4.7._ */ function toUint112(uint256 value) internal pure returns (uint112) { require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits"); return uint112(value); } /** * @dev Returns the downcasted uint104 from uint256, reverting on * overflow (when the input is greater than largest uint104). * * Counterpart to Solidity's `uint104` operator. * * Requirements: * * - input must fit into 104 bits * * _Available since v4.7._ */ function toUint104(uint256 value) internal pure returns (uint104) { require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits"); return uint104(value); } /** * @dev Returns the downcasted uint96 from uint256, reverting on * overflow (when the input is greater than largest uint96). * * Counterpart to Solidity's `uint96` operator. * * Requirements: * * - input must fit into 96 bits * * _Available since v4.2._ */ function toUint96(uint256 value) internal pure returns (uint96) { require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits"); return uint96(value); } /** * @dev Returns the downcasted uint88 from uint256, reverting on * overflow (when the input is greater than largest uint88). * * Counterpart to Solidity's `uint88` operator. * * Requirements: * * - input must fit into 88 bits * * _Available since v4.7._ */ function toUint88(uint256 value) internal pure returns (uint88) { require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits"); return uint88(value); } /** * @dev Returns the downcasted uint80 from uint256, reverting on * overflow (when the input is greater than largest uint80). * * Counterpart to Solidity's `uint80` operator. * * Requirements: * * - input must fit into 80 bits * * _Available since v4.7._ */ function toUint80(uint256 value) internal pure returns (uint80) { require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits"); return uint80(value); } /** * @dev Returns the downcasted uint72 from uint256, reverting on * overflow (when the input is greater than largest uint72). * * Counterpart to Solidity's `uint72` operator. * * Requirements: * * - input must fit into 72 bits * * _Available since v4.7._ */ function toUint72(uint256 value) internal pure returns (uint72) { require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits"); return uint72(value); } /** * @dev Returns the downcasted uint64 from uint256, reverting on * overflow (when the input is greater than largest uint64). * * Counterpart to Solidity's `uint64` operator. * * Requirements: * * - input must fit into 64 bits * * _Available since v2.5._ */ function toUint64(uint256 value) internal pure returns (uint64) { require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits"); return uint64(value); } /** * @dev Returns the downcasted uint56 from uint256, reverting on * overflow (when the input is greater than largest uint56). * * Counterpart to Solidity's `uint56` operator. * * Requirements: * * - input must fit into 56 bits * * _Available since v4.7._ */ function toUint56(uint256 value) internal pure returns (uint56) { require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits"); return uint56(value); } /** * @dev Returns the downcasted uint48 from uint256, reverting on * overflow (when the input is greater than largest uint48). * * Counterpart to Solidity's `uint48` operator. * * Requirements: * * - input must fit into 48 bits * * _Available since v4.7._ */ function toUint48(uint256 value) internal pure returns (uint48) { require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits"); return uint48(value); } /** * @dev Returns the downcasted uint40 from uint256, reverting on * overflow (when the input is greater than largest uint40). * * Counterpart to Solidity's `uint40` operator. * * Requirements: * * - input must fit into 40 bits * * _Available since v4.7._ */ function toUint40(uint256 value) internal pure returns (uint40) { require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits"); return uint40(value); } /** * @dev Returns the downcasted uint32 from uint256, reverting on * overflow (when the input is greater than largest uint32). * * Counterpart to Solidity's `uint32` operator. * * Requirements: * * - input must fit into 32 bits * * _Available since v2.5._ */ function toUint32(uint256 value) internal pure returns (uint32) { require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits"); return uint32(value); } /** * @dev Returns the downcasted uint24 from uint256, reverting on * overflow (when the input is greater than largest uint24). * * Counterpart to Solidity's `uint24` operator. * * Requirements: * * - input must fit into 24 bits * * _Available since v4.7._ */ function toUint24(uint256 value) internal pure returns (uint24) { require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits"); return uint24(value); } /** * @dev Returns the downcasted uint16 from uint256, reverting on * overflow (when the input is greater than largest uint16). * * Counterpart to Solidity's `uint16` operator. * * Requirements: * * - input must fit into 16 bits * * _Available since v2.5._ */ function toUint16(uint256 value) internal pure returns (uint16) { require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits"); return uint16(value); } /** * @dev Returns the downcasted uint8 from uint256, reverting on * overflow (when the input is greater than largest uint8). * * Counterpart to Solidity's `uint8` operator. * * Requirements: * * - input must fit into 8 bits * * _Available since v2.5._ */ function toUint8(uint256 value) internal pure returns (uint8) { require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits"); return uint8(value); } /** * @dev Converts a signed int256 into an unsigned uint256. * * Requirements: * * - input must be greater than or equal to 0. * * _Available since v3.0._ */ function toUint256(int256 value) internal pure returns (uint256) { require(value >= 0, "SafeCast: value must be positive"); return uint256(value); } /** * @dev Returns the downcasted int248 from int256, reverting on * overflow (when the input is less than smallest int248 or * greater than largest int248). * * Counterpart to Solidity's `int248` operator. * * Requirements: * * - input must fit into 248 bits * * _Available since v4.7._ */ function toInt248(int256 value) internal pure returns (int248) { require(value >= type(int248).min && value <= type(int248).max, "SafeCast: value doesn't fit in 248 bits"); return int248(value); } /** * @dev Returns the downcasted int240 from int256, reverting on * overflow (when the input is less than smallest int240 or * greater than largest int240). * * Counterpart to Solidity's `int240` operator. * * Requirements: * * - input must fit into 240 bits * * _Available since v4.7._ */ function toInt240(int256 value) internal pure returns (int240) { require(value >= type(int240).min && value <= type(int240).max, "SafeCast: value doesn't fit in 240 bits"); return int240(value); } /** * @dev Returns the downcasted int232 from int256, reverting on * overflow (when the input is less than smallest int232 or * greater than largest int232). * * Counterpart to Solidity's `int232` operator. * * Requirements: * * - input must fit into 232 bits * * _Available since v4.7._ */ function toInt232(int256 value) internal pure returns (int232) { require(value >= type(int232).min && value <= type(int232).max, "SafeCast: value doesn't fit in 232 bits"); return int232(value); } /** * @dev Returns the downcasted int224 from int256, reverting on * overflow (when the input is less than smallest int224 or * greater than largest int224). * * Counterpart to Solidity's `int224` operator. * * Requirements: * * - input must fit into 224 bits * * _Available since v4.7._ */ function toInt224(int256 value) internal pure returns (int224) { require(value >= type(int224).min && value <= type(int224).max, "SafeCast: value doesn't fit in 224 bits"); return int224(value); } /** * @dev Returns the downcasted int216 from int256, reverting on * overflow (when the input is less than smallest int216 or * greater than largest int216). * * Counterpart to Solidity's `int216` operator. * * Requirements: * * - input must fit into 216 bits * * _Available since v4.7._ */ function toInt216(int256 value) internal pure returns (int216) { require(value >= type(int216).min && value <= type(int216).max, "SafeCast: value doesn't fit in 216 bits"); return int216(value); } /** * @dev Returns the downcasted int208 from int256, reverting on * overflow (when the input is less than smallest int208 or * greater than largest int208). * * Counterpart to Solidity's `int208` operator. * * Requirements: * * - input must fit into 208 bits * * _Available since v4.7._ */ function toInt208(int256 value) internal pure returns (int208) { require(value >= type(int208).min && value <= type(int208).max, "SafeCast: value doesn't fit in 208 bits"); return int208(value); } /** * @dev Returns the downcasted int200 from int256, reverting on * overflow (when the input is less than smallest int200 or * greater than largest int200). * * Counterpart to Solidity's `int200` operator. * * Requirements: * * - input must fit into 200 bits * * _Available since v4.7._ */ function toInt200(int256 value) internal pure returns (int200) { require(value >= type(int200).min && value <= type(int200).max, "SafeCast: value doesn't fit in 200 bits"); return int200(value); } /** * @dev Returns the downcasted int192 from int256, reverting on * overflow (when the input is less than smallest int192 or * greater than largest int192). * * Counterpart to Solidity's `int192` operator. * * Requirements: * * - input must fit into 192 bits * * _Available since v4.7._ */ function toInt192(int256 value) internal pure returns (int192) { require(value >= type(int192).min && value <= type(int192).max, "SafeCast: value doesn't fit in 192 bits"); return int192(value); } /** * @dev Returns the downcasted int184 from int256, reverting on * overflow (when the input is less than smallest int184 or * greater than largest int184). * * Counterpart to Solidity's `int184` operator. * * Requirements: * * - input must fit into 184 bits * * _Available since v4.7._ */ function toInt184(int256 value) internal pure returns (int184) { require(value >= type(int184).min && value <= type(int184).max, "SafeCast: value doesn't fit in 184 bits"); return int184(value); } /** * @dev Returns the downcasted int176 from int256, reverting on * overflow (when the input is less than smallest int176 or * greater than largest int176). * * Counterpart to Solidity's `int176` operator. * * Requirements: * * - input must fit into 176 bits * * _Available since v4.7._ */ function toInt176(int256 value) internal pure returns (int176) { require(value >= type(int176).min && value <= type(int176).max, "SafeCast: value doesn't fit in 176 bits"); return int176(value); } /** * @dev Returns the downcasted int168 from int256, reverting on * overflow (when the input is less than smallest int168 or * greater than largest int168). * * Counterpart to Solidity's `int168` operator. * * Requirements: * * - input must fit into 168 bits * * _Available since v4.7._ */ function toInt168(int256 value) internal pure returns (int168) { require(value >= type(int168).min && value <= type(int168).max, "SafeCast: value doesn't fit in 168 bits"); return int168(value); } /** * @dev Returns the downcasted int160 from int256, reverting on * overflow (when the input is less than smallest int160 or * greater than largest int160). * * Counterpart to Solidity's `int160` operator. * * Requirements: * * - input must fit into 160 bits * * _Available since v4.7._ */ function toInt160(int256 value) internal pure returns (int160) { require(value >= type(int160).min && value <= type(int160).max, "SafeCast: value doesn't fit in 160 bits"); return int160(value); } /** * @dev Returns the downcasted int152 from int256, reverting on * overflow (when the input is less than smallest int152 or * greater than largest int152). * * Counterpart to Solidity's `int152` operator. * * Requirements: * * - input must fit into 152 bits * * _Available since v4.7._ */ function toInt152(int256 value) internal pure returns (int152) { require(value >= type(int152).min && value <= type(int152).max, "SafeCast: value doesn't fit in 152 bits"); return int152(value); } /** * @dev Returns the downcasted int144 from int256, reverting on * overflow (when the input is less than smallest int144 or * greater than largest int144). * * Counterpart to Solidity's `int144` operator. * * Requirements: * * - input must fit into 144 bits * * _Available since v4.7._ */ function toInt144(int256 value) internal pure returns (int144) { require(value >= type(int144).min && value <= type(int144).max, "SafeCast: value doesn't fit in 144 bits"); return int144(value); } /** * @dev Returns the downcasted int136 from int256, reverting on * overflow (when the input is less than smallest int136 or * greater than largest int136). * * Counterpart to Solidity's `int136` operator. * * Requirements: * * - input must fit into 136 bits * * _Available since v4.7._ */ function toInt136(int256 value) internal pure returns (int136) { require(value >= type(int136).min && value <= type(int136).max, "SafeCast: value doesn't fit in 136 bits"); return int136(value); } /** * @dev Returns the downcasted int128 from int256, reverting on * overflow (when the input is less than smallest int128 or * greater than largest int128). * * Counterpart to Solidity's `int128` operator. * * Requirements: * * - input must fit into 128 bits * * _Available since v3.1._ */ function toInt128(int256 value) internal pure returns (int128) { require(value >= type(int128).min && value <= type(int128).max, "SafeCast: value doesn't fit in 128 bits"); return int128(value); } /** * @dev Returns the downcasted int120 from int256, reverting on * overflow (when the input is less than smallest int120 or * greater than largest int120). * * Counterpart to Solidity's `int120` operator. * * Requirements: * * - input must fit into 120 bits * * _Available since v4.7._ */ function toInt120(int256 value) internal pure returns (int120) { require(value >= type(int120).min && value <= type(int120).max, "SafeCast: value doesn't fit in 120 bits"); return int120(value); } /** * @dev Returns the downcasted int112 from int256, reverting on * overflow (when the input is less than smallest int112 or * greater than largest int112). * * Counterpart to Solidity's `int112` operator. * * Requirements: * * - input must fit into 112 bits * * _Available since v4.7._ */ function toInt112(int256 value) internal pure returns (int112) { require(value >= type(int112).min && value <= type(int112).max, "SafeCast: value doesn't fit in 112 bits"); return int112(value); } /** * @dev Returns the downcasted int104 from int256, reverting on * overflow (when the input is less than smallest int104 or * greater than largest int104). * * Counterpart to Solidity's `int104` operator. * * Requirements: * * - input must fit into 104 bits * * _Available since v4.7._ */ function toInt104(int256 value) internal pure returns (int104) { require(value >= type(int104).min && value <= type(int104).max, "SafeCast: value doesn't fit in 104 bits"); return int104(value); } /** * @dev Returns the downcasted int96 from int256, reverting on * overflow (when the input is less than smallest int96 or * greater than largest int96). * * Counterpart to Solidity's `int96` operator. * * Requirements: * * - input must fit into 96 bits * * _Available since v4.7._ */ function toInt96(int256 value) internal pure returns (int96) { require(value >= type(int96).min && value <= type(int96).max, "SafeCast: value doesn't fit in 96 bits"); return int96(value); } /** * @dev Returns the downcasted int88 from int256, reverting on * overflow (when the input is less than smallest int88 or * greater than largest int88). * * Counterpart to Solidity's `int88` operator. * * Requirements: * * - input must fit into 88 bits * * _Available since v4.7._ */ function toInt88(int256 value) internal pure returns (int88) { require(value >= type(int88).min && value <= type(int88).max, "SafeCast: value doesn't fit in 88 bits"); return int88(value); } /** * @dev Returns the downcasted int80 from int256, reverting on * overflow (when the input is less than smallest int80 or * greater than largest int80). * * Counterpart to Solidity's `int80` operator. * * Requirements: * * - input must fit into 80 bits * * _Available since v4.7._ */ function toInt80(int256 value) internal pure returns (int80) { require(value >= type(int80).min && value <= type(int80).max, "SafeCast: value doesn't fit in 80 bits"); return int80(value); } /** * @dev Returns the downcasted int72 from int256, reverting on * overflow (when the input is less than smallest int72 or * greater than largest int72). * * Counterpart to Solidity's `int72` operator. * * Requirements: * * - input must fit into 72 bits * * _Available since v4.7._ */ function toInt72(int256 value) internal pure returns (int72) { require(value >= type(int72).min && value <= type(int72).max, "SafeCast: value doesn't fit in 72 bits"); return int72(value); } /** * @dev Returns the downcasted int64 from int256, reverting on * overflow (when the input is less than smallest int64 or * greater than largest int64). * * Counterpart to Solidity's `int64` operator. * * Requirements: * * - input must fit into 64 bits * * _Available since v3.1._ */ function toInt64(int256 value) internal pure returns (int64) { require(value >= type(int64).min && value <= type(int64).max, "SafeCast: value doesn't fit in 64 bits"); return int64(value); } /** * @dev Returns the downcasted int56 from int256, reverting on * overflow (when the input is less than smallest int56 or * greater than largest int56). * * Counterpart to Solidity's `int56` operator. * * Requirements: * * - input must fit into 56 bits * * _Available since v4.7._ */ function toInt56(int256 value) internal pure returns (int56) { require(value >= type(int56).min && value <= type(int56).max, "SafeCast: value doesn't fit in 56 bits"); return int56(value); } /** * @dev Returns the downcasted int48 from int256, reverting on * overflow (when the input is less than smallest int48 or * greater than largest int48). * * Counterpart to Solidity's `int48` operator. * * Requirements: * * - input must fit into 48 bits * * _Available since v4.7._ */ function toInt48(int256 value) internal pure returns (int48) { require(value >= type(int48).min && value <= type(int48).max, "SafeCast: value doesn't fit in 48 bits"); return int48(value); } /** * @dev Returns the downcasted int40 from int256, reverting on * overflow (when the input is less than smallest int40 or * greater than largest int40). * * Counterpart to Solidity's `int40` operator. * * Requirements: * * - input must fit into 40 bits * * _Available since v4.7._ */ function toInt40(int256 value) internal pure returns (int40) { require(value >= type(int40).min && value <= type(int40).max, "SafeCast: value doesn't fit in 40 bits"); return int40(value); } /** * @dev Returns the downcasted int32 from int256, reverting on * overflow (when the input is less than smallest int32 or * greater than largest int32). * * Counterpart to Solidity's `int32` operator. * * Requirements: * * - input must fit into 32 bits * * _Available since v3.1._ */ function toInt32(int256 value) internal pure returns (int32) { require(value >= type(int32).min && value <= type(int32).max, "SafeCast: value doesn't fit in 32 bits"); return int32(value); } /** * @dev Returns the downcasted int24 from int256, reverting on * overflow (when the input is less than smallest int24 or * greater than largest int24). * * Counterpart to Solidity's `int24` operator. * * Requirements: * * - input must fit into 24 bits * * _Available since v4.7._ */ function toInt24(int256 value) internal pure returns (int24) { require(value >= type(int24).min && value <= type(int24).max, "SafeCast: value doesn't fit in 24 bits"); return int24(value); } /** * @dev Returns the downcasted int16 from int256, reverting on * overflow (when the input is less than smallest int16 or * greater than largest int16). * * Counterpart to Solidity's `int16` operator. * * Requirements: * * - input must fit into 16 bits * * _Available since v3.1._ */ function toInt16(int256 value) internal pure returns (int16) { require(value >= type(int16).min && value <= type(int16).max, "SafeCast: value doesn't fit in 16 bits"); return int16(value); } /** * @dev Returns the downcasted int8 from int256, reverting on * overflow (when the input is less than smallest int8 or * greater than largest int8). * * Counterpart to Solidity's `int8` operator. * * Requirements: * * - input must fit into 8 bits * * _Available since v3.1._ */ function toInt8(int256 value) internal pure returns (int8) { require(value >= type(int8).min && value <= type(int8).max, "SafeCast: value doesn't fit in 8 bits"); return int8(value); } /** * @dev Converts an unsigned uint256 into a signed int256. * * Requirements: * * - input must be less than or equal to maxInt256. * * _Available since v3.0._ */ function toInt256(uint256 value) internal pure returns (int256) { // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256"); return int256(value); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol) pragma solidity ^0.8.0; // CAUTION // This version of SafeMath should only be used with Solidity 0.8 or later, // because it relies on the compiler's built in overflow checks. /** * @dev Wrappers over Solidity's arithmetic operations. * * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler * now has built in overflow checking. */ library SafeMath { /** * @dev Returns the addition of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { uint256 c = a + b; if (c < a) return (false, 0); return (true, c); } } /** * @dev Returns the subtraction of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b > a) return (false, 0); return (true, a - b); } } /** * @dev Returns the multiplication of two unsigned integers, with an overflow flag. * * _Available since v3.4._ */ function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { // 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-contracts/pull/522 if (a == 0) return (true, 0); uint256 c = a * b; if (c / a != b) return (false, 0); return (true, c); } } /** * @dev Returns the division of two unsigned integers, with a division by zero flag. * * _Available since v3.4._ */ function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b == 0) return (false, 0); return (true, a / b); } } /** * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag. * * _Available since v3.4._ */ function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) { unchecked { if (b == 0) return (false, 0); return (true, a % b); } } /** * @dev Returns the addition of two unsigned integers, reverting on * overflow. * * Counterpart to Solidity's `+` operator. * * Requirements: * * - Addition cannot overflow. */ function add(uint256 a, uint256 b) internal pure returns (uint256) { return a + b; } /** * @dev Returns the subtraction of two unsigned integers, reverting on * overflow (when the result is negative). * * Counterpart to Solidity's `-` operator. * * Requirements: * * - Subtraction cannot overflow. */ function sub(uint256 a, uint256 b) internal pure returns (uint256) { return a - b; } /** * @dev Returns the multiplication of two unsigned integers, reverting on * overflow. * * Counterpart to Solidity's `*` operator. * * Requirements: * * - Multiplication cannot overflow. */ function mul(uint256 a, uint256 b) internal pure returns (uint256) { return a * b; } /** * @dev Returns the integer division of two unsigned integers, reverting on * division by zero. The result is rounded towards zero. * * Counterpart to Solidity's `/` operator. * * Requirements: * * - The divisor cannot be zero. */ function div(uint256 a, uint256 b) internal pure returns (uint256) { return a / b; } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * reverting when dividing by zero. * * Counterpart to Solidity's `%` operator. This function uses a `revert` * opcode (which leaves remaining gas untouched) while Solidity uses an * invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function mod(uint256 a, uint256 b) internal pure returns (uint256) { return a % b; } /** * @dev Returns the subtraction of two unsigned integers, reverting with custom message on * overflow (when the result is negative). * * CAUTION: This function is deprecated because it requires allocating memory for the error * message unnecessarily. For custom revert reasons use {trySub}. * * Counterpart to Solidity's `-` operator. * * Requirements: * * - Subtraction cannot overflow. */ function sub( uint256 a, uint256 b, string memory errorMessage ) internal pure returns (uint256) { unchecked { require(b <= a, errorMessage); return a - b; } } /** * @dev Returns the integer division of two unsigned integers, reverting with custom message on * division by zero. The result is rounded towards zero. * * Counterpart to Solidity's `/` operator. Note: this function uses a * `revert` opcode (which leaves remaining gas untouched) while Solidity * uses an invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function div( uint256 a, uint256 b, string memory errorMessage ) internal pure returns (uint256) { unchecked { require(b > 0, errorMessage); return a / b; } } /** * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo), * reverting with custom message when dividing by zero. * * CAUTION: This function is deprecated because it requires allocating memory for the error * message unnecessarily. For custom revert reasons use {tryMod}. * * Counterpart to Solidity's `%` operator. This function uses a `revert` * opcode (which leaves remaining gas untouched) while Solidity uses an * invalid opcode to revert (consuming all remaining gas). * * Requirements: * * - The divisor cannot be zero. */ function mod( uint256 a, uint256 b, string memory errorMessage ) internal pure returns (uint256) { unchecked { require(b > 0, errorMessage); return a % b; } } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol) pragma solidity ^0.8.0; /** * @dev String operations. */ library Strings { bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef"; uint8 private constant _ADDRESS_LENGTH = 20; /** * @dev Converts a `uint256` to its ASCII `string` decimal representation. */ function toString(uint256 value) internal pure returns (string memory) { // Inspired by OraclizeAPI's implementation - MIT licence // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol if (value == 0) { return "0"; } uint256 temp = value; uint256 digits; while (temp != 0) { digits++; temp /= 10; } bytes memory buffer = new bytes(digits); while (value != 0) { digits -= 1; buffer[digits] = bytes1(uint8(48 + uint256(value % 10))); value /= 10; } return string(buffer); } /** * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation. */ function toHexString(uint256 value) internal pure returns (string memory) { if (value == 0) { return "0x00"; } uint256 temp = value; uint256 length = 0; while (temp != 0) { length++; temp >>= 8; } return toHexString(value, length); } /** * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length. */ function toHexString(uint256 value, uint256 length) internal pure returns (string memory) { bytes memory buffer = new bytes(2 * length + 2); buffer[0] = "0"; buffer[1] = "x"; for (uint256 i = 2 * length + 1; i > 1; --i) { buffer[i] = _HEX_SYMBOLS[value & 0xf]; value >>= 4; } require(value == 0, "Strings: hex length insufficient"); return string(buffer); } /** * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation. */ function toHexString(address addr) internal pure returns (string memory) { return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH); } } 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; } 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; } pragma solidity >=0.6.2; 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); } pragma solidity >=0.6.2; import './IUniswapV2Router01.sol'; 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; } //SPDX-License-Identifier: MIT pragma solidity ^0.8.0; import "@openzeppelin/contracts/token/ERC20/extensions/ERC20VotesComp.sol"; import "@openzeppelin/contracts/access/Ownable.sol"; import "@openzeppelin/contracts/utils/math/SafeMath.sol"; import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol"; import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol"; import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol"; import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol"; contract Token is ERC20VotesComp, Ownable{ using SafeMath for uint256; uint public buyFees; uint public sellFees; uint public totalFee; uint256 public swapTokensAtAmount = 1_000_000 * 10** decimals(); uint256 public tokenMaxCap = 2_000_000_000 * 10** decimals(); bool public inSwapAndLiquify = false; address public timelock; address public feeWallet; IUniswapV2Router02 public uniswapV2Router; address public uniswapV2Pair; address public WETH; mapping(address => bool) public isAutomatedMarketMakerPair; mapping(address => bool) public isExcludedFromTxFees; modifier isOwnerOrTimelock() { require(msg.sender == owner() || msg.sender == timelock, "Not owner or timelock"); _; } constructor() ERC20("Yearn Meme Finance", "yMEME") ERC20Permit("yMEME") { _mint(msg.sender, 1_000_000_000 * 10 ** decimals()); feeWallet = msg.sender; address _router = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D; IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(_router); WETH = _uniswapV2Router.WETH(); uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this), WETH); uniswapV2Router = _uniswapV2Router; isExcludedFromTxFees[address(this)] = true; isExcludedFromTxFees[msg.sender] = true; _setAutomatedMarketMakerPair(uniswapV2Pair, true); } function _transfer( address sender, address recipient, uint256 amount ) internal virtual override { require(sender != address(0), "ERC20: transfer from the zero address"); require(recipient != address(0), "ERC20: transfer to the zero address"); require(balanceOf(sender) >= amount, "ERC20: transfer amount exceeds balance"); if (amount == 0) { super._transfer(sender, recipient, 0); return; } bool canSwap = balanceOf(address(this)) >= swapTokensAtAmount; // console.log("swap tokens at amount ", swapTokensAtAmount); // console.log("contractTokenBalance ", balanceOf(address(this))); // console.log("in swap ", inSwapAndLiquify); // console.log("can swap ", canSwap); // console.log("owner ", owner()); // console.log("sender ", sender); // console.log("recipient ", recipient); // console.log("!isAutomatedMarketMakerPair[sender] ", !isAutomatedMarketMakerPair[sender]); if ( canSwap && !inSwapAndLiquify && !isAutomatedMarketMakerPair[sender] ) { inSwapAndLiquify = true; swapTokensForEth(balanceOf(address(this))); payable(feeWallet).transfer(address(this).balance); inSwapAndLiquify = false; } uint256 totalContractFee = shouldTakeFee(sender, recipient) ? takeFee(sender, recipient, amount) : 0; // console.log("total contract fee ", totalContractFee); // console.log("sender ", sender, address(this)); // console.log("recipient ", recipient); // console.log("amount ", amount, balanceOf(sender)); // console.log("before balance", balanceOf(sender), balanceOf(recipient)); super._transfer(sender, address(this), totalContractFee); super._transfer(sender, recipient, amount.sub(totalContractFee)); // console.log("final balance", balanceOf(sender), balanceOf(recipient)); // console.log("HERERE 3"); } function swapTokensForEth(uint256 tokenAmount) private { // generate the pancakeswap pair path of token -> weth address[] memory path = new address[](2); path[0] = address(this); path[1] = uniswapV2Router.WETH(); _approve(address(this), address(uniswapV2Router), tokenAmount); // make the swap // console.log("HERERE", tokenAmount); uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens( tokenAmount, 0, // accept any amount of ETH path, address(this), block.timestamp * 2 ); // console.log("HERERE 2"); } function shouldTakeFee(address sender, address recipient) internal view returns (bool) { return !isExcludedFromTxFees[sender] && !isExcludedFromTxFees[recipient]; } function calcPercent(uint amount, uint percentBP) internal pure returns (uint) { return amount.mul(percentBP).div(10000); } function takeFee(address sender, address recipient, uint256 amount) internal view returns (uint256) { uint appliedFee; if(isAutomatedMarketMakerPair[sender]) { appliedFee = buyFees; } else if(isAutomatedMarketMakerPair[recipient]) { appliedFee = sellFees; } return calcPercent(amount, appliedFee); } function mint(address _user, uint256 amount) external isOwnerOrTimelock { require(totalSupply().add(amount) <= tokenMaxCap, "Max cap reached"); _mint(_user, amount); } function setTimelock(address _timelock) external isOwnerOrTimelock { timelock = _timelock; } function setFees(uint _buyFees, uint _sellFees) external isOwnerOrTimelock { require(_buyFees <= 500 && _sellFees <= 500, "Buy fees too high"); buyFees = _buyFees; sellFees = _sellFees; } function setFeeWallet(address _feeWallet) external isOwnerOrTimelock { feeWallet = _feeWallet; } function toggleExcludeFromFees(address _address) external isOwnerOrTimelock { isExcludedFromTxFees[_address] = !isExcludedFromTxFees[_address]; } function setSwapTokensAtAmount(uint256 amount) external isOwnerOrTimelock { swapTokensAtAmount = amount; } function setAutomatedMarketMakerPair(address pair, bool value) external isOwnerOrTimelock { require(pair != uniswapV2Pair, "The Uniswap pair cannot be removed from automatedMarketMakerPairs"); _setAutomatedMarketMakerPair(pair, value); } function _setAutomatedMarketMakerPair(address pair, bool value) private { require(isAutomatedMarketMakerPair[pair] != value, "NNN: Automated market maker pair is already set to that value"); isAutomatedMarketMakerPair[pair] = value; } receive() external payable { } }