{{ "language": "Solidity", "sources": { "contracts/protocol/boxsteth.sol": { "content": "// SPDX-License-Identifier: GPL-3.0-or-later\r\npragma solidity ^0.8.4;\r\n\r\n/* \r\n @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ \r\n @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ \r\n @@@@@@ @@@@@ \r\n @@@@@ @@@@@ \r\n @@@@@ @@@@@ \r\n @@@@@ @@ @@@@@ \r\n @@@@@ @@@@@@ @@@@ \r\n @@@@@ @@@@@@@ \r\n @@@@@ @@@ @@@@@@@@@@@ \r\n @@@@@ @@@@@@ @@@@@@@@@@@@@@@ \r\n @@@@@ @@@@@@@@@@@@@@@@@@@@ @@@@ \r\n @@@@@ @@@@@@@@@@@@@@@ @@ @@@@@@ \r\n @@@@@ @@@@@@@@@@ @@@ @@@@@@@ \r\n @@@@@ @@@@@ @@ @@@@@@@@@@@@ \r\n @@@@@ @@@@ @@@@@@@@@@@ \r\n @@@@@ @@@@@@@@@@@@@@@@@@@@@ \r\n @@@@@ @@@@@@@@@@@@@@@@@@@@@@@ \r\n @@@@@ @@@@@ @@@@@@@@@ \r\n @@@@@ @@@@@@@@@@ \r\n @@@@@ @@@@@@@@@@@@ \r\n @@@@@ @@@@@@@@@@@@@ \r\n @@@@@@ @@@@@@@@@@@@@@@ \r\n @@@@@@ @@@@@@@@@@@@@@@@ \r\n @@@@@@@ @@@@@@@@@@@@@@@@@@ \r\n @@@@@@@@@ @@@@@@@@@@@@@@@@@@@@ \r\n @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\r\n*/\r\n\r\nimport {ERC20} from \"@openzeppelin/contracts/token/ERC20/ERC20.sol\";\r\nimport {AccessControl} from \"@openzeppelin/contracts/access/AccessControl.sol\";\r\nimport {SafeERC20} from \"@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol\";\r\n\r\ncontract boxsteth is ERC20, AccessControl {\r\n\r\n using SafeERC20 for ERC20;\r\n\r\n bytes32 public constant ADMIN_ROLE = keccak256(\"ADMIN\");\r\n\r\n constructor(string memory name, string memory symbol) ERC20(name, symbol) {\r\n _setupRole(ADMIN_ROLE, _msgSender());\r\n _setRoleAdmin(ADMIN_ROLE, ADMIN_ROLE); \r\n }\r\n\r\n function mint(address recipient, uint256 amount) external onlyRole(ADMIN_ROLE) {\r\n _mint(recipient, amount);\r\n }\r\n\r\n function burn(uint256 amount) external {\r\n _burn(_msgSender(), amount);\r\n }\r\n\r\n function burnFrom(address account, uint256 amount) external {\r\n require(allowance(account, _msgSender()) - amount >= 0, \"burn amount exceeds allowance\");\r\n uint256 newAllowance = allowance(account, _msgSender());\r\n _approve(account, _msgSender(), newAllowance);\r\n _burn(account, amount);\r\n }\r\n}\r\n" }, "@openzeppelin/contracts/token/ERC20/ERC20.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC20.sol\";\nimport \"./extensions/IERC20Metadata.sol\";\nimport \"../../utils/Context.sol\";\n\n/**\n * @dev Implementation of the {IERC20} interface.\n *\n * This implementation is agnostic to the way tokens are created. This means\n * that a supply mechanism has to be added in a derived contract using {_mint}.\n * For a generic mechanism see {ERC20PresetMinterPauser}.\n *\n * TIP: For a detailed writeup see our guide\n * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How\n * to implement supply mechanisms].\n *\n * We have followed general OpenZeppelin Contracts guidelines: functions revert\n * instead returning `false` on failure. This behavior is nonetheless\n * conventional and does not conflict with the expectations of ERC20\n * applications.\n *\n * Additionally, an {Approval} event is emitted on calls to {transferFrom}.\n * This allows applications to reconstruct the allowance for all accounts just\n * by listening to said events. Other implementations of the EIP may not emit\n * these events, as it isn't required by the specification.\n *\n * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}\n * functions have been added to mitigate the well-known issues around setting\n * allowances. See {IERC20-approve}.\n */\ncontract ERC20 is Context, IERC20, IERC20Metadata {\n mapping(address => uint256) private _balances;\n\n mapping(address => mapping(address => uint256)) private _allowances;\n\n uint256 private _totalSupply;\n\n string private _name;\n string private _symbol;\n\n /**\n * @dev Sets the values for {name} and {symbol}.\n *\n * The default value of {decimals} is 18. To select a different value for\n * {decimals} you should overload it.\n *\n * All two of these values are immutable: they can only be set once during\n * construction.\n */\n constructor(string memory name_, string memory symbol_) {\n _name = name_;\n _symbol = symbol_;\n }\n\n /**\n * @dev Returns the name of the token.\n */\n function name() public view virtual override returns (string memory) {\n return _name;\n }\n\n /**\n * @dev Returns the symbol of the token, usually a shorter version of the\n * name.\n */\n function symbol() public view virtual override returns (string memory) {\n return _symbol;\n }\n\n /**\n * @dev Returns the number of decimals used to get its user representation.\n * For example, if `decimals` equals `2`, a balance of `505` tokens should\n * be displayed to a user as `5.05` (`505 / 10 ** 2`).\n *\n * Tokens usually opt for a value of 18, imitating the relationship between\n * Ether and Wei. This is the value {ERC20} uses, unless this function is\n * overridden;\n *\n * NOTE: This information is only used for _display_ purposes: it in\n * no way affects any of the arithmetic of the contract, including\n * {IERC20-balanceOf} and {IERC20-transfer}.\n */\n function decimals() public view virtual override returns (uint8) {\n return 18;\n }\n\n /**\n * @dev See {IERC20-totalSupply}.\n */\n function totalSupply() public view virtual override returns (uint256) {\n return _totalSupply;\n }\n\n /**\n * @dev See {IERC20-balanceOf}.\n */\n function balanceOf(address account) public view virtual override returns (uint256) {\n return _balances[account];\n }\n\n /**\n * @dev See {IERC20-transfer}.\n *\n * Requirements:\n *\n * - `to` cannot be the zero address.\n * - the caller must have a balance of at least `amount`.\n */\n function transfer(address to, uint256 amount) public virtual override returns (bool) {\n address owner = _msgSender();\n _transfer(owner, to, amount);\n return true;\n }\n\n /**\n * @dev See {IERC20-allowance}.\n */\n function allowance(address owner, address spender) public view virtual override returns (uint256) {\n return _allowances[owner][spender];\n }\n\n /**\n * @dev See {IERC20-approve}.\n *\n * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on\n * `transferFrom`. This is semantically equivalent to an infinite approval.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n */\n function approve(address spender, uint256 amount) public virtual override returns (bool) {\n address owner = _msgSender();\n _approve(owner, spender, amount);\n return true;\n }\n\n /**\n * @dev See {IERC20-transferFrom}.\n *\n * Emits an {Approval} event indicating the updated allowance. This is not\n * required by the EIP. See the note at the beginning of {ERC20}.\n *\n * NOTE: Does not update the allowance if the current allowance\n * is the maximum `uint256`.\n *\n * Requirements:\n *\n * - `from` and `to` cannot be the zero address.\n * - `from` must have a balance of at least `amount`.\n * - the caller must have allowance for ``from``'s tokens of at least\n * `amount`.\n */\n function transferFrom(\n address from,\n address to,\n uint256 amount\n ) public virtual override returns (bool) {\n address spender = _msgSender();\n _spendAllowance(from, spender, amount);\n _transfer(from, to, amount);\n return true;\n }\n\n /**\n * @dev Atomically increases the allowance granted to `spender` by the caller.\n *\n * This is an alternative to {approve} that can be used as a mitigation for\n * problems described in {IERC20-approve}.\n *\n * Emits an {Approval} event indicating the updated allowance.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n */\n function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {\n address owner = _msgSender();\n _approve(owner, spender, allowance(owner, spender) + addedValue);\n return true;\n }\n\n /**\n * @dev Atomically decreases the allowance granted to `spender` by the caller.\n *\n * This is an alternative to {approve} that can be used as a mitigation for\n * problems described in {IERC20-approve}.\n *\n * Emits an {Approval} event indicating the updated allowance.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n * - `spender` must have allowance for the caller of at least\n * `subtractedValue`.\n */\n function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {\n address owner = _msgSender();\n uint256 currentAllowance = allowance(owner, spender);\n require(currentAllowance >= subtractedValue, \"ERC20: decreased allowance below zero\");\n unchecked {\n _approve(owner, spender, currentAllowance - subtractedValue);\n }\n\n return true;\n }\n\n /**\n * @dev Moves `amount` of tokens from `from` to `to`.\n *\n * This internal function is equivalent to {transfer}, and can be used to\n * e.g. implement automatic token fees, slashing mechanisms, etc.\n *\n * Emits a {Transfer} event.\n *\n * Requirements:\n *\n * - `from` cannot be the zero address.\n * - `to` cannot be the zero address.\n * - `from` must have a balance of at least `amount`.\n */\n function _transfer(\n address from,\n address to,\n uint256 amount\n ) internal virtual {\n require(from != address(0), \"ERC20: transfer from the zero address\");\n require(to != address(0), \"ERC20: transfer to the zero address\");\n\n _beforeTokenTransfer(from, to, amount);\n\n uint256 fromBalance = _balances[from];\n require(fromBalance >= amount, \"ERC20: transfer amount exceeds balance\");\n unchecked {\n _balances[from] = fromBalance - amount;\n // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by\n // decrementing then incrementing.\n _balances[to] += amount;\n }\n\n emit Transfer(from, to, amount);\n\n _afterTokenTransfer(from, to, amount);\n }\n\n /** @dev Creates `amount` tokens and assigns them to `account`, increasing\n * the total supply.\n *\n * Emits a {Transfer} event with `from` set to the zero address.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n */\n function _mint(address account, uint256 amount) internal virtual {\n require(account != address(0), \"ERC20: mint to the zero address\");\n\n _beforeTokenTransfer(address(0), account, amount);\n\n _totalSupply += amount;\n unchecked {\n // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.\n _balances[account] += amount;\n }\n emit Transfer(address(0), account, amount);\n\n _afterTokenTransfer(address(0), account, amount);\n }\n\n /**\n * @dev Destroys `amount` tokens from `account`, reducing the\n * total supply.\n *\n * Emits a {Transfer} event with `to` set to the zero address.\n *\n * Requirements:\n *\n * - `account` cannot be the zero address.\n * - `account` must have at least `amount` tokens.\n */\n function _burn(address account, uint256 amount) internal virtual {\n require(account != address(0), \"ERC20: burn from the zero address\");\n\n _beforeTokenTransfer(account, address(0), amount);\n\n uint256 accountBalance = _balances[account];\n require(accountBalance >= amount, \"ERC20: burn amount exceeds balance\");\n unchecked {\n _balances[account] = accountBalance - amount;\n // Overflow not possible: amount <= accountBalance <= totalSupply.\n _totalSupply -= amount;\n }\n\n emit Transfer(account, address(0), amount);\n\n _afterTokenTransfer(account, address(0), amount);\n }\n\n /**\n * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.\n *\n * This internal function is equivalent to `approve`, and can be used to\n * e.g. set automatic allowances for certain subsystems, etc.\n *\n * Emits an {Approval} event.\n *\n * Requirements:\n *\n * - `owner` cannot be the zero address.\n * - `spender` cannot be the zero address.\n */\n function _approve(\n address owner,\n address spender,\n uint256 amount\n ) internal virtual {\n require(owner != address(0), \"ERC20: approve from the zero address\");\n require(spender != address(0), \"ERC20: approve to the zero address\");\n\n _allowances[owner][spender] = amount;\n emit Approval(owner, spender, amount);\n }\n\n /**\n * @dev Updates `owner` s allowance for `spender` based on spent `amount`.\n *\n * Does not update the allowance amount in case of infinite allowance.\n * Revert if not enough allowance is available.\n *\n * Might emit an {Approval} event.\n */\n function _spendAllowance(\n address owner,\n address spender,\n uint256 amount\n ) internal virtual {\n uint256 currentAllowance = allowance(owner, spender);\n if (currentAllowance != type(uint256).max) {\n require(currentAllowance >= amount, \"ERC20: insufficient allowance\");\n unchecked {\n _approve(owner, spender, currentAllowance - amount);\n }\n }\n }\n\n /**\n * @dev Hook that is called before any transfer of tokens. This includes\n * minting and burning.\n *\n * Calling conditions:\n *\n * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens\n * will be transferred to `to`.\n * - when `from` is zero, `amount` tokens will be minted for `to`.\n * - when `to` is zero, `amount` of ``from``'s tokens will be burned.\n * - `from` and `to` are never both zero.\n *\n * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n */\n function _beforeTokenTransfer(\n address from,\n address to,\n uint256 amount\n ) internal virtual {}\n\n /**\n * @dev Hook that is called after any transfer of tokens. This includes\n * minting and burning.\n *\n * Calling conditions:\n *\n * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens\n * has been transferred to `to`.\n * - when `from` is zero, `amount` tokens have been minted for `to`.\n * - when `to` is zero, `amount` of ``from``'s tokens have been burned.\n * - `from` and `to` are never both zero.\n *\n * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n */\n function _afterTokenTransfer(\n address from,\n address to,\n uint256 amount\n ) internal virtual {}\n}\n" }, "@openzeppelin/contracts/access/AccessControl.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (access/AccessControl.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IAccessControl.sol\";\nimport \"../utils/Context.sol\";\nimport \"../utils/Strings.sol\";\nimport \"../utils/introspection/ERC165.sol\";\n\n/**\n * @dev Contract module that allows children to implement role-based access\n * control mechanisms. This is a lightweight version that doesn't allow enumerating role\n * members except through off-chain means by accessing the contract event logs. Some\n * applications may benefit from on-chain enumerability, for those cases see\n * {AccessControlEnumerable}.\n *\n * Roles are referred to by their `bytes32` identifier. These should be exposed\n * in the external API and be unique. The best way to achieve this is by\n * using `public constant` hash digests:\n *\n * ```\n * bytes32 public constant MY_ROLE = keccak256(\"MY_ROLE\");\n * ```\n *\n * Roles can be used to represent a set of permissions. To restrict access to a\n * function call, use {hasRole}:\n *\n * ```\n * function foo() public {\n * require(hasRole(MY_ROLE, msg.sender));\n * ...\n * }\n * ```\n *\n * Roles can be granted and revoked dynamically via the {grantRole} and\n * {revokeRole} functions. Each role has an associated admin role, and only\n * accounts that have a role's admin role can call {grantRole} and {revokeRole}.\n *\n * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means\n * that only accounts with this role will be able to grant or revoke other\n * roles. More complex role relationships can be created by using\n * {_setRoleAdmin}.\n *\n * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to\n * grant and revoke this role. Extra precautions should be taken to secure\n * accounts that have been granted it.\n */\nabstract contract AccessControl is Context, IAccessControl, ERC165 {\n struct RoleData {\n mapping(address => bool) members;\n bytes32 adminRole;\n }\n\n mapping(bytes32 => RoleData) private _roles;\n\n bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;\n\n /**\n * @dev Modifier that checks that an account has a specific role. Reverts\n * with a standardized message including the required role.\n *\n * The format of the revert reason is given by the following regular expression:\n *\n * /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/\n *\n * _Available since v4.1._\n */\n modifier onlyRole(bytes32 role) {\n _checkRole(role);\n _;\n }\n\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);\n }\n\n /**\n * @dev Returns `true` if `account` has been granted `role`.\n */\n function hasRole(bytes32 role, address account) public view virtual override returns (bool) {\n return _roles[role].members[account];\n }\n\n /**\n * @dev Revert with a standard message if `_msgSender()` is missing `role`.\n * Overriding this function changes the behavior of the {onlyRole} modifier.\n *\n * Format of the revert message is described in {_checkRole}.\n *\n * _Available since v4.6._\n */\n function _checkRole(bytes32 role) internal view virtual {\n _checkRole(role, _msgSender());\n }\n\n /**\n * @dev Revert with a standard message if `account` is missing `role`.\n *\n * The format of the revert reason is given by the following regular expression:\n *\n * /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/\n */\n function _checkRole(bytes32 role, address account) internal view virtual {\n if (!hasRole(role, account)) {\n revert(\n string(\n abi.encodePacked(\n \"AccessControl: account \",\n Strings.toHexString(account),\n \" is missing role \",\n Strings.toHexString(uint256(role), 32)\n )\n )\n );\n }\n }\n\n /**\n * @dev Returns the admin role that controls `role`. See {grantRole} and\n * {revokeRole}.\n *\n * To change a role's admin, use {_setRoleAdmin}.\n */\n function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {\n return _roles[role].adminRole;\n }\n\n /**\n * @dev Grants `role` to `account`.\n *\n * If `account` had not been already granted `role`, emits a {RoleGranted}\n * event.\n *\n * Requirements:\n *\n * - the caller must have ``role``'s admin role.\n *\n * May emit a {RoleGranted} event.\n */\n function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {\n _grantRole(role, account);\n }\n\n /**\n * @dev Revokes `role` from `account`.\n *\n * If `account` had been granted `role`, emits a {RoleRevoked} event.\n *\n * Requirements:\n *\n * - the caller must have ``role``'s admin role.\n *\n * May emit a {RoleRevoked} event.\n */\n function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {\n _revokeRole(role, account);\n }\n\n /**\n * @dev Revokes `role` from the calling account.\n *\n * Roles are often managed via {grantRole} and {revokeRole}: this function's\n * purpose is to provide a mechanism for accounts to lose their privileges\n * if they are compromised (such as when a trusted device is misplaced).\n *\n * If the calling account had been revoked `role`, emits a {RoleRevoked}\n * event.\n *\n * Requirements:\n *\n * - the caller must be `account`.\n *\n * May emit a {RoleRevoked} event.\n */\n function renounceRole(bytes32 role, address account) public virtual override {\n require(account == _msgSender(), \"AccessControl: can only renounce roles for self\");\n\n _revokeRole(role, account);\n }\n\n /**\n * @dev Grants `role` to `account`.\n *\n * If `account` had not been already granted `role`, emits a {RoleGranted}\n * event. Note that unlike {grantRole}, this function doesn't perform any\n * checks on the calling account.\n *\n * May emit a {RoleGranted} event.\n *\n * [WARNING]\n * ====\n * This function should only be called from the constructor when setting\n * up the initial roles for the system.\n *\n * Using this function in any other way is effectively circumventing the admin\n * system imposed by {AccessControl}.\n * ====\n *\n * NOTE: This function is deprecated in favor of {_grantRole}.\n */\n function _setupRole(bytes32 role, address account) internal virtual {\n _grantRole(role, account);\n }\n\n /**\n * @dev Sets `adminRole` as ``role``'s admin role.\n *\n * Emits a {RoleAdminChanged} event.\n */\n function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {\n bytes32 previousAdminRole = getRoleAdmin(role);\n _roles[role].adminRole = adminRole;\n emit RoleAdminChanged(role, previousAdminRole, adminRole);\n }\n\n /**\n * @dev Grants `role` to `account`.\n *\n * Internal function without access restriction.\n *\n * May emit a {RoleGranted} event.\n */\n function _grantRole(bytes32 role, address account) internal virtual {\n if (!hasRole(role, account)) {\n _roles[role].members[account] = true;\n emit RoleGranted(role, account, _msgSender());\n }\n }\n\n /**\n * @dev Revokes `role` from `account`.\n *\n * Internal function without access restriction.\n *\n * May emit a {RoleRevoked} event.\n */\n function _revokeRole(bytes32 role, address account) internal virtual {\n if (hasRole(role, account)) {\n _roles[role].members[account] = false;\n emit RoleRevoked(role, account, _msgSender());\n }\n }\n}\n" }, "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/utils/SafeERC20.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC20.sol\";\nimport \"../extensions/draft-IERC20Permit.sol\";\nimport \"../../../utils/Address.sol\";\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n using Address for address;\n\n function safeTransfer(\n IERC20 token,\n address to,\n uint256 value\n ) internal {\n _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n }\n\n function safeTransferFrom(\n IERC20 token,\n address from,\n address to,\n uint256 value\n ) internal {\n _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n }\n\n /**\n * @dev Deprecated. This function has issues similar to the ones found in\n * {IERC20-approve}, and its usage is discouraged.\n *\n * Whenever possible, use {safeIncreaseAllowance} and\n * {safeDecreaseAllowance} instead.\n */\n function safeApprove(\n IERC20 token,\n address spender,\n uint256 value\n ) internal {\n // safeApprove should only be called when setting an initial allowance,\n // or when resetting it to zero. To increase and decrease it, use\n // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'\n require(\n (value == 0) || (token.allowance(address(this), spender) == 0),\n \"SafeERC20: approve from non-zero to non-zero allowance\"\n );\n _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n }\n\n function safeIncreaseAllowance(\n IERC20 token,\n address spender,\n uint256 value\n ) internal {\n uint256 newAllowance = token.allowance(address(this), spender) + value;\n _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n }\n\n function safeDecreaseAllowance(\n IERC20 token,\n address spender,\n uint256 value\n ) internal {\n unchecked {\n uint256 oldAllowance = token.allowance(address(this), spender);\n require(oldAllowance >= value, \"SafeERC20: decreased allowance below zero\");\n uint256 newAllowance = oldAllowance - value;\n _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n }\n }\n\n function safePermit(\n IERC20Permit token,\n address owner,\n address spender,\n uint256 value,\n uint256 deadline,\n uint8 v,\n bytes32 r,\n bytes32 s\n ) internal {\n uint256 nonceBefore = token.nonces(owner);\n token.permit(owner, spender, value, deadline, v, r, s);\n uint256 nonceAfter = token.nonces(owner);\n require(nonceAfter == nonceBefore + 1, \"SafeERC20: permit did not succeed\");\n }\n\n /**\n * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n * on the return value: the return value is optional (but if data is returned, it must not be false).\n * @param token The token targeted by the call.\n * @param data The call data (encoded using abi.encode or one of its variants).\n */\n function _callOptionalReturn(IERC20 token, bytes memory data) private {\n // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since\n // we're implementing it ourselves. We use {Address-functionCall} to perform this call, which verifies that\n // the target address contains contract code and also asserts for success in the low-level call.\n\n bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n if (returndata.length > 0) {\n // Return data is optional\n require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n }\n }\n}\n" }, "@openzeppelin/contracts/token/ERC20/IERC20.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n /**\n * @dev Emitted when `value` tokens are moved from one account (`from`) to\n * another (`to`).\n *\n * Note that `value` may be zero.\n */\n event Transfer(address indexed from, address indexed to, uint256 value);\n\n /**\n * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n * a call to {approve}. `value` is the new allowance.\n */\n event Approval(address indexed owner, address indexed spender, uint256 value);\n\n /**\n * @dev Returns the amount of tokens in existence.\n */\n function totalSupply() external view returns (uint256);\n\n /**\n * @dev Returns the amount of tokens owned by `account`.\n */\n function balanceOf(address account) external view returns (uint256);\n\n /**\n * @dev Moves `amount` tokens from the caller's account to `to`.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transfer(address to, uint256 amount) external returns (bool);\n\n /**\n * @dev Returns the remaining number of tokens that `spender` will be\n * allowed to spend on behalf of `owner` through {transferFrom}. This is\n * zero by default.\n *\n * This value changes when {approve} or {transferFrom} are called.\n */\n function allowance(address owner, address spender) external view returns (uint256);\n\n /**\n * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * IMPORTANT: Beware that changing an allowance with this method brings the risk\n * that someone may use both the old and the new allowance by unfortunate\n * transaction ordering. One possible solution to mitigate this race\n * condition is to first reduce the spender's allowance to 0 and set the\n * desired value afterwards:\n * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n *\n * Emits an {Approval} event.\n */\n function approve(address spender, uint256 amount) external returns (bool);\n\n /**\n * @dev Moves `amount` tokens from `from` to `to` using the\n * allowance mechanism. `amount` is then deducted from the caller's\n * allowance.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(\n address from,\n address to,\n uint256 amount\n ) external returns (bool);\n}\n" }, "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)\n\npragma solidity ^0.8.0;\n\nimport \"../IERC20.sol\";\n\n/**\n * @dev Interface for the optional metadata functions from the ERC20 standard.\n *\n * _Available since v4.1._\n */\ninterface IERC20Metadata is IERC20 {\n /**\n * @dev Returns the name of the token.\n */\n function name() external view returns (string memory);\n\n /**\n * @dev Returns the symbol of the token.\n */\n function symbol() external view returns (string memory);\n\n /**\n * @dev Returns the decimals places of the token.\n */\n function decimals() external view returns (uint8);\n}\n" }, "@openzeppelin/contracts/utils/Context.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n function _msgSender() internal view virtual returns (address) {\n return msg.sender;\n }\n\n function _msgData() internal view virtual returns (bytes calldata) {\n return msg.data;\n }\n}\n" }, "@openzeppelin/contracts/access/IAccessControl.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev External interface of AccessControl declared to support ERC165 detection.\n */\ninterface IAccessControl {\n /**\n * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`\n *\n * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite\n * {RoleAdminChanged} not being emitted signaling this.\n *\n * _Available since v3.1._\n */\n event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);\n\n /**\n * @dev Emitted when `account` is granted `role`.\n *\n * `sender` is the account that originated the contract call, an admin role\n * bearer except when using {AccessControl-_setupRole}.\n */\n event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);\n\n /**\n * @dev Emitted when `account` is revoked `role`.\n *\n * `sender` is the account that originated the contract call:\n * - if using `revokeRole`, it is the admin role bearer\n * - if using `renounceRole`, it is the role bearer (i.e. `account`)\n */\n event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);\n\n /**\n * @dev Returns `true` if `account` has been granted `role`.\n */\n function hasRole(bytes32 role, address account) external view returns (bool);\n\n /**\n * @dev Returns the admin role that controls `role`. See {grantRole} and\n * {revokeRole}.\n *\n * To change a role's admin, use {AccessControl-_setRoleAdmin}.\n */\n function getRoleAdmin(bytes32 role) external view returns (bytes32);\n\n /**\n * @dev Grants `role` to `account`.\n *\n * If `account` had not been already granted `role`, emits a {RoleGranted}\n * event.\n *\n * Requirements:\n *\n * - the caller must have ``role``'s admin role.\n */\n function grantRole(bytes32 role, address account) external;\n\n /**\n * @dev Revokes `role` from `account`.\n *\n * If `account` had been granted `role`, emits a {RoleRevoked} event.\n *\n * Requirements:\n *\n * - the caller must have ``role``'s admin role.\n */\n function revokeRole(bytes32 role, address account) external;\n\n /**\n * @dev Revokes `role` from the calling account.\n *\n * Roles are often managed via {grantRole} and {revokeRole}: this function's\n * purpose is to provide a mechanism for accounts to lose their privileges\n * if they are compromised (such as when a trusted device is misplaced).\n *\n * If the calling account had been granted `role`, emits a {RoleRevoked}\n * event.\n *\n * Requirements:\n *\n * - the caller must be `account`.\n */\n function renounceRole(bytes32 role, address account) external;\n}\n" }, "@openzeppelin/contracts/utils/Strings.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./math/Math.sol\";\n\n/**\n * @dev String operations.\n */\nlibrary Strings {\n bytes16 private constant _SYMBOLS = \"0123456789abcdef\";\n uint8 private constant _ADDRESS_LENGTH = 20;\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` decimal representation.\n */\n function toString(uint256 value) internal pure returns (string memory) {\n unchecked {\n uint256 length = Math.log10(value) + 1;\n string memory buffer = new string(length);\n uint256 ptr;\n /// @solidity memory-safe-assembly\n assembly {\n ptr := add(buffer, add(32, length))\n }\n while (true) {\n ptr--;\n /// @solidity memory-safe-assembly\n assembly {\n mstore8(ptr, byte(mod(value, 10), _SYMBOLS))\n }\n value /= 10;\n if (value == 0) break;\n }\n return buffer;\n }\n }\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.\n */\n function toHexString(uint256 value) internal pure returns (string memory) {\n unchecked {\n return toHexString(value, Math.log256(value) + 1);\n }\n }\n\n /**\n * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.\n */\n function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {\n bytes memory buffer = new bytes(2 * length + 2);\n buffer[0] = \"0\";\n buffer[1] = \"x\";\n for (uint256 i = 2 * length + 1; i > 1; --i) {\n buffer[i] = _SYMBOLS[value & 0xf];\n value >>= 4;\n }\n require(value == 0, \"Strings: hex length insufficient\");\n return string(buffer);\n }\n\n /**\n * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.\n */\n function toHexString(address addr) internal pure returns (string memory) {\n return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);\n }\n}\n" }, "@openzeppelin/contracts/utils/introspection/ERC165.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)\n\npragma solidity ^0.8.0;\n\nimport \"./IERC165.sol\";\n\n/**\n * @dev Implementation of the {IERC165} interface.\n *\n * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check\n * for the additional interface id that will be supported. For example:\n *\n * ```solidity\n * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n * return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);\n * }\n * ```\n *\n * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.\n */\nabstract contract ERC165 is IERC165 {\n /**\n * @dev See {IERC165-supportsInterface}.\n */\n function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {\n return interfaceId == type(IERC165).interfaceId;\n }\n}\n" }, "@openzeppelin/contracts/utils/math/Math.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Standard math utilities missing in the Solidity language.\n */\nlibrary Math {\n enum Rounding {\n Down, // Toward negative infinity\n Up, // Toward infinity\n Zero // Toward zero\n }\n\n /**\n * @dev Returns the largest of two numbers.\n */\n function max(uint256 a, uint256 b) internal pure returns (uint256) {\n return a > b ? a : b;\n }\n\n /**\n * @dev Returns the smallest of two numbers.\n */\n function min(uint256 a, uint256 b) internal pure returns (uint256) {\n return a < b ? a : b;\n }\n\n /**\n * @dev Returns the average of two numbers. The result is rounded towards\n * zero.\n */\n function average(uint256 a, uint256 b) internal pure returns (uint256) {\n // (a + b) / 2 can overflow.\n return (a & b) + (a ^ b) / 2;\n }\n\n /**\n * @dev Returns the ceiling of the division of two numbers.\n *\n * This differs from standard division with `/` in that it rounds up instead\n * of rounding down.\n */\n function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {\n // (a + b - 1) / b can overflow on addition, so we distribute.\n return a == 0 ? 0 : (a - 1) / b + 1;\n }\n\n /**\n * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0\n * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)\n * with further edits by Uniswap Labs also under MIT license.\n */\n function mulDiv(\n uint256 x,\n uint256 y,\n uint256 denominator\n ) internal pure returns (uint256 result) {\n unchecked {\n // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use\n // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256\n // variables such that product = prod1 * 2^256 + prod0.\n uint256 prod0; // Least significant 256 bits of the product\n uint256 prod1; // Most significant 256 bits of the product\n assembly {\n let mm := mulmod(x, y, not(0))\n prod0 := mul(x, y)\n prod1 := sub(sub(mm, prod0), lt(mm, prod0))\n }\n\n // Handle non-overflow cases, 256 by 256 division.\n if (prod1 == 0) {\n return prod0 / denominator;\n }\n\n // Make sure the result is less than 2^256. Also prevents denominator == 0.\n require(denominator > prod1);\n\n ///////////////////////////////////////////////\n // 512 by 256 division.\n ///////////////////////////////////////////////\n\n // Make division exact by subtracting the remainder from [prod1 prod0].\n uint256 remainder;\n assembly {\n // Compute remainder using mulmod.\n remainder := mulmod(x, y, denominator)\n\n // Subtract 256 bit number from 512 bit number.\n prod1 := sub(prod1, gt(remainder, prod0))\n prod0 := sub(prod0, remainder)\n }\n\n // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.\n // See https://cs.stackexchange.com/q/138556/92363.\n\n // Does not overflow because the denominator cannot be zero at this stage in the function.\n uint256 twos = denominator & (~denominator + 1);\n assembly {\n // Divide denominator by twos.\n denominator := div(denominator, twos)\n\n // Divide [prod1 prod0] by twos.\n prod0 := div(prod0, twos)\n\n // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.\n twos := add(div(sub(0, twos), twos), 1)\n }\n\n // Shift in bits from prod1 into prod0.\n prod0 |= prod1 * twos;\n\n // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such\n // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for\n // four bits. That is, denominator * inv = 1 mod 2^4.\n uint256 inverse = (3 * denominator) ^ 2;\n\n // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works\n // in modular arithmetic, doubling the correct bits in each step.\n inverse *= 2 - denominator * inverse; // inverse mod 2^8\n inverse *= 2 - denominator * inverse; // inverse mod 2^16\n inverse *= 2 - denominator * inverse; // inverse mod 2^32\n inverse *= 2 - denominator * inverse; // inverse mod 2^64\n inverse *= 2 - denominator * inverse; // inverse mod 2^128\n inverse *= 2 - denominator * inverse; // inverse mod 2^256\n\n // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.\n // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is\n // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1\n // is no longer required.\n result = prod0 * inverse;\n return result;\n }\n }\n\n /**\n * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.\n */\n function mulDiv(\n uint256 x,\n uint256 y,\n uint256 denominator,\n Rounding rounding\n ) internal pure returns (uint256) {\n uint256 result = mulDiv(x, y, denominator);\n if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {\n result += 1;\n }\n return result;\n }\n\n /**\n * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.\n *\n * Inspired by Henry S. Warren, Jr.'s \"Hacker's Delight\" (Chapter 11).\n */\n function sqrt(uint256 a) internal pure returns (uint256) {\n if (a == 0) {\n return 0;\n }\n\n // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.\n //\n // We know that the \"msb\" (most significant bit) of our target number `a` is a power of 2 such that we have\n // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.\n //\n // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`\n // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`\n // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`\n //\n // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.\n uint256 result = 1 << (log2(a) >> 1);\n\n // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,\n // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at\n // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision\n // into the expected uint128 result.\n unchecked {\n result = (result + a / result) >> 1;\n result = (result + a / result) >> 1;\n result = (result + a / result) >> 1;\n result = (result + a / result) >> 1;\n result = (result + a / result) >> 1;\n result = (result + a / result) >> 1;\n result = (result + a / result) >> 1;\n return min(result, a / result);\n }\n }\n\n /**\n * @notice Calculates sqrt(a), following the selected rounding direction.\n */\n function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {\n unchecked {\n uint256 result = sqrt(a);\n return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);\n }\n }\n\n /**\n * @dev Return the log in base 2, rounded down, of a positive value.\n * Returns 0 if given 0.\n */\n function log2(uint256 value) internal pure returns (uint256) {\n uint256 result = 0;\n unchecked {\n if (value >> 128 > 0) {\n value >>= 128;\n result += 128;\n }\n if (value >> 64 > 0) {\n value >>= 64;\n result += 64;\n }\n if (value >> 32 > 0) {\n value >>= 32;\n result += 32;\n }\n if (value >> 16 > 0) {\n value >>= 16;\n result += 16;\n }\n if (value >> 8 > 0) {\n value >>= 8;\n result += 8;\n }\n if (value >> 4 > 0) {\n value >>= 4;\n result += 4;\n }\n if (value >> 2 > 0) {\n value >>= 2;\n result += 2;\n }\n if (value >> 1 > 0) {\n result += 1;\n }\n }\n return result;\n }\n\n /**\n * @dev Return the log in base 2, following the selected rounding direction, of a positive value.\n * Returns 0 if given 0.\n */\n function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {\n unchecked {\n uint256 result = log2(value);\n return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);\n }\n }\n\n /**\n * @dev Return the log in base 10, rounded down, of a positive value.\n * Returns 0 if given 0.\n */\n function log10(uint256 value) internal pure returns (uint256) {\n uint256 result = 0;\n unchecked {\n if (value >= 10**64) {\n value /= 10**64;\n result += 64;\n }\n if (value >= 10**32) {\n value /= 10**32;\n result += 32;\n }\n if (value >= 10**16) {\n value /= 10**16;\n result += 16;\n }\n if (value >= 10**8) {\n value /= 10**8;\n result += 8;\n }\n if (value >= 10**4) {\n value /= 10**4;\n result += 4;\n }\n if (value >= 10**2) {\n value /= 10**2;\n result += 2;\n }\n if (value >= 10**1) {\n result += 1;\n }\n }\n return result;\n }\n\n /**\n * @dev Return the log in base 10, following the selected rounding direction, of a positive value.\n * Returns 0 if given 0.\n */\n function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {\n unchecked {\n uint256 result = log10(value);\n return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);\n }\n }\n\n /**\n * @dev Return the log in base 256, rounded down, of a positive value.\n * Returns 0 if given 0.\n *\n * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.\n */\n function log256(uint256 value) internal pure returns (uint256) {\n uint256 result = 0;\n unchecked {\n if (value >> 128 > 0) {\n value >>= 128;\n result += 16;\n }\n if (value >> 64 > 0) {\n value >>= 64;\n result += 8;\n }\n if (value >> 32 > 0) {\n value >>= 32;\n result += 4;\n }\n if (value >> 16 > 0) {\n value >>= 16;\n result += 2;\n }\n if (value >> 8 > 0) {\n result += 1;\n }\n }\n return result;\n }\n\n /**\n * @dev Return the log in base 10, following the selected rounding direction, of a positive value.\n * Returns 0 if given 0.\n */\n function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {\n unchecked {\n uint256 result = log256(value);\n return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);\n }\n }\n}\n" }, "@openzeppelin/contracts/utils/introspection/IERC165.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC165 standard, as defined in the\n * https://eips.ethereum.org/EIPS/eip-165[EIP].\n *\n * Implementers can declare support of contract interfaces, which can then be\n * queried by others ({ERC165Checker}).\n *\n * For an implementation, see {ERC165}.\n */\ninterface IERC165 {\n /**\n * @dev Returns true if this contract implements the interface defined by\n * `interfaceId`. See the corresponding\n * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]\n * to learn more about how these ids are created.\n *\n * This function call must use less than 30 000 gas.\n */\n function supportsInterface(bytes4 interfaceId) external view returns (bool);\n}\n" }, "@openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)\n\npragma solidity ^0.8.0;\n\n/**\n * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in\n * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].\n *\n * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by\n * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't\n * need to send a transaction, and thus is not required to hold Ether at all.\n */\ninterface IERC20Permit {\n /**\n * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,\n * given ``owner``'s signed approval.\n *\n * IMPORTANT: The same issues {IERC20-approve} has related to transaction\n * ordering also apply here.\n *\n * Emits an {Approval} event.\n *\n * Requirements:\n *\n * - `spender` cannot be the zero address.\n * - `deadline` must be a timestamp in the future.\n * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`\n * over the EIP712-formatted function arguments.\n * - the signature must use ``owner``'s current nonce (see {nonces}).\n *\n * For more information on the signature format, see the\n * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP\n * section].\n */\n function permit(\n address owner,\n address spender,\n uint256 value,\n uint256 deadline,\n uint8 v,\n bytes32 r,\n bytes32 s\n ) external;\n\n /**\n * @dev Returns the current nonce for `owner`. This value must be\n * included whenever a signature is generated for {permit}.\n *\n * Every successful call to {permit} increases ``owner``'s nonce by one. This\n * prevents a signature from being used multiple times.\n */\n function nonces(address owner) external view returns (uint256);\n\n /**\n * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.\n */\n // solhint-disable-next-line func-name-mixedcase\n function DOMAIN_SEPARATOR() external view returns (bytes32);\n}\n" }, "@openzeppelin/contracts/utils/Address.sol": { "content": "// SPDX-License-Identifier: MIT\n// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)\n\npragma solidity ^0.8.1;\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n /**\n * @dev Returns true if `account` is a contract.\n *\n * [IMPORTANT]\n * ====\n * It is unsafe to assume that an address for which this function returns\n * false is an externally-owned account (EOA) and not a contract.\n *\n * Among others, `isContract` will return false for the following\n * types of addresses:\n *\n * - an externally-owned account\n * - a contract in construction\n * - an address where a contract will be created\n * - an address where a contract lived, but was destroyed\n * ====\n *\n * [IMPORTANT]\n * ====\n * You shouldn't rely on `isContract` to protect against flash loan attacks!\n *\n * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets\n * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract\n * constructor.\n * ====\n */\n function isContract(address account) internal view returns (bool) {\n // This method relies on extcodesize/address.code.length, which returns 0\n // for contracts in construction, since the code is only stored at the end\n // of the constructor execution.\n\n return account.code.length > 0;\n }\n\n /**\n * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n * `recipient`, forwarding all available gas and reverting on errors.\n *\n * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n * of certain opcodes, possibly making contracts go over the 2300 gas limit\n * imposed by `transfer`, making them unable to receive funds via\n * `transfer`. {sendValue} removes this limitation.\n *\n * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n *\n * IMPORTANT: because control is transferred to `recipient`, care must be\n * taken to not create reentrancy vulnerabilities. Consider using\n * {ReentrancyGuard} or the\n * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n */\n function sendValue(address payable recipient, uint256 amount) internal {\n require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n (bool success, ) = recipient.call{value: amount}(\"\");\n require(success, \"Address: unable to send value, recipient may have reverted\");\n }\n\n /**\n * @dev Performs a Solidity function call using a low level `call`. A\n * plain `call` is an unsafe replacement for a function call: use this\n * function instead.\n *\n * If `target` reverts with a revert reason, it is bubbled up by this\n * function (like regular Solidity function calls).\n *\n * Returns the raw returned data. To convert to the expected return value,\n * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n *\n * Requirements:\n *\n * - `target` must be a contract.\n * - calling `target` with `data` must not revert.\n *\n * _Available since v3.1._\n */\n function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionCallWithValue(target, data, 0, \"Address: low-level call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n * `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal returns (bytes memory) {\n return functionCallWithValue(target, data, 0, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but also transferring `value` wei to `target`.\n *\n * Requirements:\n *\n * - the calling contract must have an ETH balance of at least `value`.\n * - the called Solidity function must be `payable`.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(\n address target,\n bytes memory data,\n uint256 value\n ) internal returns (bytes memory) {\n return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n * with `errorMessage` as a fallback revert reason when `target` reverts.\n *\n * _Available since v3.1._\n */\n function functionCallWithValue(\n address target,\n bytes memory data,\n uint256 value,\n string memory errorMessage\n ) internal returns (bytes memory) {\n require(address(this).balance >= value, \"Address: insufficient balance for call\");\n (bool success, bytes memory returndata) = target.call{value: value}(data);\n return verifyCallResultFromTarget(target, success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n return functionStaticCall(target, data, \"Address: low-level static call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a static call.\n *\n * _Available since v3.3._\n */\n function functionStaticCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal view returns (bytes memory) {\n (bool success, bytes memory returndata) = target.staticcall(data);\n return verifyCallResultFromTarget(target, success, returndata, errorMessage);\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n }\n\n /**\n * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n * but performing a delegate call.\n *\n * _Available since v3.4._\n */\n function functionDelegateCall(\n address target,\n bytes memory data,\n string memory errorMessage\n ) internal returns (bytes memory) {\n (bool success, bytes memory returndata) = target.delegatecall(data);\n return verifyCallResultFromTarget(target, success, returndata, errorMessage);\n }\n\n /**\n * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling\n * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.\n *\n * _Available since v4.8._\n */\n function verifyCallResultFromTarget(\n address target,\n bool success,\n bytes memory returndata,\n string memory errorMessage\n ) internal view returns (bytes memory) {\n if (success) {\n if (returndata.length == 0) {\n // only check isContract if the call was successful and the return data is empty\n // otherwise we already know that it was a contract\n require(isContract(target), \"Address: call to non-contract\");\n }\n return returndata;\n } else {\n _revert(returndata, errorMessage);\n }\n }\n\n /**\n * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the\n * revert reason or using the provided one.\n *\n * _Available since v4.3._\n */\n function verifyCallResult(\n bool success,\n bytes memory returndata,\n string memory errorMessage\n ) internal pure returns (bytes memory) {\n if (success) {\n return returndata;\n } else {\n _revert(returndata, errorMessage);\n }\n }\n\n function _revert(bytes memory returndata, string memory errorMessage) private pure {\n // Look for revert reason and bubble it up if present\n if (returndata.length > 0) {\n // The easiest way to bubble the revert reason is using memory via assembly\n /// @solidity memory-safe-assembly\n assembly {\n let returndata_size := mload(returndata)\n revert(add(32, returndata), returndata_size)\n }\n } else {\n revert(errorMessage);\n }\n }\n}\n" } }, "settings": { "optimizer": { "enabled": true, "runs": 1000 }, "outputSelection": { "*": { "*": [ "evm.bytecode", "evm.deployedBytecode", "devdoc", "userdoc", "metadata", "abi" ] } }, "libraries": {} } }}

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