// This contract is part of Zellic’s smart contract dataset, which is a collection of publicly available contract code gathered as of March 2023. // 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; } } // OpenZeppelin Contracts (last updated v4.7.0) (utils/structs/EnumerableSet.sol) pragma solidity ^0.8.0; /** * @dev Library for managing * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive * types. * * Sets have the following properties: * * - Elements are added, removed, and checked for existence in constant time * (O(1)). * - Elements are enumerated in O(n). No guarantees are made on the ordering. * * ``` * contract Example { * // Add the library methods * using EnumerableSet for EnumerableSet.AddressSet; * * // Declare a set state variable * EnumerableSet.AddressSet private mySet; * } * ``` * * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`) * and `uint256` (`UintSet`) are supported. * * [WARNING] * ==== * Trying to delete such a structure from storage will likely result in data corruption, rendering the structure unusable. * See https://github.com/ethereum/solidity/pull/11843[ethereum/solidity#11843] for more info. * * In order to clean an EnumerableSet, you can either remove all elements one by one or create a fresh instance using an array of EnumerableSet. * ==== */ library EnumerableSet { // To implement this library for multiple types with as little code // repetition as possible, we write it in terms of a generic Set type with // bytes32 values. // The Set implementation uses private functions, and user-facing // implementations (such as AddressSet) are just wrappers around the // underlying Set. // This means that we can only create new EnumerableSets for types that fit // in bytes32. struct Set { // Storage of set values bytes32[] _values; // Position of the value in the `values` array, plus 1 because index 0 // means a value is not in the set. mapping(bytes32 => uint256) _indexes; } /** * @dev Add a value to a set. O(1). * * Returns true if the value was added to the set, that is if it was not * already present. */ function _add(Set storage set, bytes32 value) private returns (bool) { if (!_contains(set, value)) { set._values.push(value); // The value is stored at length-1, but we add 1 to all indexes // and use 0 as a sentinel value set._indexes[value] = set._values.length; return true; } else { return false; } } /** * @dev Removes a value from a set. O(1). * * Returns true if the value was removed from the set, that is if it was * present. */ function _remove(Set storage set, bytes32 value) private returns (bool) { // We read and store the value's index to prevent multiple reads from the same storage slot uint256 valueIndex = set._indexes[value]; if (valueIndex != 0) { // Equivalent to contains(set, value) // To delete an element from the _values array in O(1), we swap the element to delete with the last one in // the array, and then remove the last element (sometimes called as 'swap and pop'). // This modifies the order of the array, as noted in {at}. uint256 toDeleteIndex = valueIndex - 1; uint256 lastIndex = set._values.length - 1; if (lastIndex != toDeleteIndex) { bytes32 lastValue = set._values[lastIndex]; // Move the last value to the index where the value to delete is set._values[toDeleteIndex] = lastValue; // Update the index for the moved value set._indexes[lastValue] = valueIndex; // Replace lastValue's index to valueIndex } // Delete the slot where the moved value was stored set._values.pop(); // Delete the index for the deleted slot delete set._indexes[value]; return true; } else { return false; } } /** * @dev Returns true if the value is in the set. O(1). */ function _contains(Set storage set, bytes32 value) private view returns (bool) { return set._indexes[value] != 0; } /** * @dev Returns the number of values on the set. O(1). */ function _length(Set storage set) private view returns (uint256) { return set._values.length; } /** * @dev Returns the value stored at position `index` in the set. O(1). * * Note that there are no guarantees on the ordering of values inside the * array, and it may change when more values are added or removed. * * Requirements: * * - `index` must be strictly less than {length}. */ function _at(Set storage set, uint256 index) private view returns (bytes32) { return set._values[index]; } /** * @dev Return the entire set in an array * * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that * this function has an unbounded cost, and using it as part of a state-changing function may render the function * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block. */ function _values(Set storage set) private view returns (bytes32[] memory) { return set._values; } // Bytes32Set struct Bytes32Set { Set _inner; } /** * @dev Add a value to a set. O(1). * * Returns true if the value was added to the set, that is if it was not * already present. */ function add(Bytes32Set storage set, bytes32 value) internal returns (bool) { return _add(set._inner, value); } /** * @dev Removes a value from a set. O(1). * * Returns true if the value was removed from the set, that is if it was * present. */ function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) { return _remove(set._inner, value); } /** * @dev Returns true if the value is in the set. O(1). */ function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) { return _contains(set._inner, value); } /** * @dev Returns the number of values in the set. O(1). */ function length(Bytes32Set storage set) internal view returns (uint256) { return _length(set._inner); } /** * @dev Returns the value stored at position `index` in the set. O(1). * * Note that there are no guarantees on the ordering of values inside the * array, and it may change when more values are added or removed. * * Requirements: * * - `index` must be strictly less than {length}. */ function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) { return _at(set._inner, index); } /** * @dev Return the entire set in an array * * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that * this function has an unbounded cost, and using it as part of a state-changing function may render the function * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block. */ function values(Bytes32Set storage set) internal view returns (bytes32[] memory) { return _values(set._inner); } // AddressSet struct AddressSet { Set _inner; } /** * @dev Add a value to a set. O(1). * * Returns true if the value was added to the set, that is if it was not * already present. */ function add(AddressSet storage set, address value) internal returns (bool) { return _add(set._inner, bytes32(uint256(uint160(value)))); } /** * @dev Removes a value from a set. O(1). * * Returns true if the value was removed from the set, that is if it was * present. */ function remove(AddressSet storage set, address value) internal returns (bool) { return _remove(set._inner, bytes32(uint256(uint160(value)))); } /** * @dev Returns true if the value is in the set. O(1). */ function contains(AddressSet storage set, address value) internal view returns (bool) { return _contains(set._inner, bytes32(uint256(uint160(value)))); } /** * @dev Returns the number of values in the set. O(1). */ function length(AddressSet storage set) internal view returns (uint256) { return _length(set._inner); } /** * @dev Returns the value stored at position `index` in the set. O(1). * * Note that there are no guarantees on the ordering of values inside the * array, and it may change when more values are added or removed. * * Requirements: * * - `index` must be strictly less than {length}. */ function at(AddressSet storage set, uint256 index) internal view returns (address) { return address(uint160(uint256(_at(set._inner, index)))); } /** * @dev Return the entire set in an array * * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that * this function has an unbounded cost, and using it as part of a state-changing function may render the function * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block. */ function values(AddressSet storage set) internal view returns (address[] memory) { bytes32[] memory store = _values(set._inner); address[] memory result; /// @solidity memory-safe-assembly assembly { result := store } return result; } // UintSet struct UintSet { Set _inner; } /** * @dev Add a value to a set. O(1). * * Returns true if the value was added to the set, that is if it was not * already present. */ function add(UintSet storage set, uint256 value) internal returns (bool) { return _add(set._inner, bytes32(value)); } /** * @dev Removes a value from a set. O(1). * * Returns true if the value was removed from the set, that is if it was * present. */ function remove(UintSet storage set, uint256 value) internal returns (bool) { return _remove(set._inner, bytes32(value)); } /** * @dev Returns true if the value is in the set. O(1). */ function contains(UintSet storage set, uint256 value) internal view returns (bool) { return _contains(set._inner, bytes32(value)); } /** * @dev Returns the number of values on the set. O(1). */ function length(UintSet storage set) internal view returns (uint256) { return _length(set._inner); } /** * @dev Returns the value stored at position `index` in the set. O(1). * * Note that there are no guarantees on the ordering of values inside the * array, and it may change when more values are added or removed. * * Requirements: * * - `index` must be strictly less than {length}. */ function at(UintSet storage set, uint256 index) internal view returns (uint256) { return uint256(_at(set._inner, index)); } /** * @dev Return the entire set in an array * * WARNING: This operation will copy the entire storage to memory, which can be quite expensive. This is designed * to mostly be used by view accessors that are queried without any gas fees. Developers should keep in mind that * this function has an unbounded cost, and using it as part of a state-changing function may render the function * uncallable if the set grows to a point where copying to memory consumes too much gas to fit in a block. */ function values(UintSet storage set) internal view returns (uint256[] memory) { bytes32[] memory store = _values(set._inner); uint256[] memory result; /// @solidity memory-safe-assembly assembly { result := store } return result; } } // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol) pragma solidity ^0.8.0; /** * @dev Interface of the ERC165 standard, as defined in the * https://eips.ethereum.org/EIPS/eip-165[EIP]. * * Implementers can declare support of contract interfaces, which can then be * queried by others ({ERC165Checker}). * * For an implementation, see {ERC165}. */ interface IERC165 { /** * @dev Returns true if this contract implements the interface defined by * `interfaceId`. See the corresponding * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section] * to learn more about how these ids are created. * * This function call must use less than 30 000 gas. */ function supportsInterface(bytes4 interfaceId) external view returns (bool); } // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol) pragma solidity ^0.8.0; /** * @dev Implementation of the {IERC165} interface. * * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check * for the additional interface id that will be supported. For example: * * ```solidity * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { * return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId); * } * ``` * * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation. */ abstract contract ERC165 is IERC165 { /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { return interfaceId == type(IERC165).interfaceId; } } // 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); } } // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol) pragma solidity ^0.8.0; /** * @dev External interface of AccessControl declared to support ERC165 detection. */ interface IAccessControl { /** * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole` * * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite * {RoleAdminChanged} not being emitted signaling this. * * _Available since v3.1._ */ event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole); /** * @dev Emitted when `account` is granted `role`. * * `sender` is the account that originated the contract call, an admin role * bearer except when using {AccessControl-_setupRole}. */ event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender); /** * @dev Emitted when `account` is revoked `role`. * * `sender` is the account that originated the contract call: * - if using `revokeRole`, it is the admin role bearer * - if using `renounceRole`, it is the role bearer (i.e. `account`) */ event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender); /** * @dev Returns `true` if `account` has been granted `role`. */ function hasRole(bytes32 role, address account) external view returns (bool); /** * @dev Returns the admin role that controls `role`. See {grantRole} and * {revokeRole}. * * To change a role's admin, use {AccessControl-_setRoleAdmin}. */ function getRoleAdmin(bytes32 role) external view returns (bytes32); /** * @dev Grants `role` to `account`. * * If `account` had not been already granted `role`, emits a {RoleGranted} * event. * * Requirements: * * - the caller must have ``role``'s admin role. */ function grantRole(bytes32 role, address account) external; /** * @dev Revokes `role` from `account`. * * If `account` had been granted `role`, emits a {RoleRevoked} event. * * Requirements: * * - the caller must have ``role``'s admin role. */ function revokeRole(bytes32 role, address account) external; /** * @dev Revokes `role` from the calling account. * * Roles are often managed via {grantRole} and {revokeRole}: this function's * purpose is to provide a mechanism for accounts to lose their privileges * if they are compromised (such as when a trusted device is misplaced). * * If the calling account had been granted `role`, emits a {RoleRevoked} * event. * * Requirements: * * - the caller must be `account`. */ function renounceRole(bytes32 role, address account) external; } // OpenZeppelin Contracts (last updated v4.7.0) (access/AccessControl.sol) pragma solidity ^0.8.0; /** * @dev Contract module that allows children to implement role-based access * control mechanisms. This is a lightweight version that doesn't allow enumerating role * members except through off-chain means by accessing the contract event logs. Some * applications may benefit from on-chain enumerability, for those cases see * {AccessControlEnumerable}. * * Roles are referred to by their `bytes32` identifier. These should be exposed * in the external API and be unique. The best way to achieve this is by * using `public constant` hash digests: * * ``` * bytes32 public constant MY_ROLE = keccak256("MY_ROLE"); * ``` * * Roles can be used to represent a set of permissions. To restrict access to a * function call, use {hasRole}: * * ``` * function foo() public { * require(hasRole(MY_ROLE, msg.sender)); * ... * } * ``` * * Roles can be granted and revoked dynamically via the {grantRole} and * {revokeRole} functions. Each role has an associated admin role, and only * accounts that have a role's admin role can call {grantRole} and {revokeRole}. * * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means * that only accounts with this role will be able to grant or revoke other * roles. More complex role relationships can be created by using * {_setRoleAdmin}. * * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to * grant and revoke this role. Extra precautions should be taken to secure * accounts that have been granted it. */ abstract contract AccessControl is Context, IAccessControl, ERC165 { struct RoleData { mapping(address => bool) members; bytes32 adminRole; } mapping(bytes32 => RoleData) private _roles; bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00; /** * @dev Modifier that checks that an account has a specific role. Reverts * with a standardized message including the required role. * * The format of the revert reason is given by the following regular expression: * * /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/ * * _Available since v4.1._ */ modifier onlyRole(bytes32 role) { _checkRole(role); _; } /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId); } /** * @dev Returns `true` if `account` has been granted `role`. */ function hasRole(bytes32 role, address account) public view virtual override returns (bool) { return _roles[role].members[account]; } /** * @dev Revert with a standard message if `_msgSender()` is missing `role`. * Overriding this function changes the behavior of the {onlyRole} modifier. * * Format of the revert message is described in {_checkRole}. * * _Available since v4.6._ */ function _checkRole(bytes32 role) internal view virtual { _checkRole(role, _msgSender()); } /** * @dev Revert with a standard message if `account` is missing `role`. * * The format of the revert reason is given by the following regular expression: * * /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/ */ function _checkRole(bytes32 role, address account) internal view virtual { if (!hasRole(role, account)) { revert( string( abi.encodePacked( "AccessControl: account ", Strings.toHexString(account), " is missing role ", Strings.toHexString(uint256(role), 32) ) ) ); } } /** * @dev Returns the admin role that controls `role`. See {grantRole} and * {revokeRole}. * * To change a role's admin, use {_setRoleAdmin}. */ function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) { return _roles[role].adminRole; } /** * @dev Grants `role` to `account`. * * If `account` had not been already granted `role`, emits a {RoleGranted} * event. * * Requirements: * * - the caller must have ``role``'s admin role. * * May emit a {RoleGranted} event. */ function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) { _grantRole(role, account); } /** * @dev Revokes `role` from `account`. * * If `account` had been granted `role`, emits a {RoleRevoked} event. * * Requirements: * * - the caller must have ``role``'s admin role. * * May emit a {RoleRevoked} event. */ function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) { _revokeRole(role, account); } /** * @dev Revokes `role` from the calling account. * * Roles are often managed via {grantRole} and {revokeRole}: this function's * purpose is to provide a mechanism for accounts to lose their privileges * if they are compromised (such as when a trusted device is misplaced). * * If the calling account had been revoked `role`, emits a {RoleRevoked} * event. * * Requirements: * * - the caller must be `account`. * * May emit a {RoleRevoked} event. */ function renounceRole(bytes32 role, address account) public virtual override { require(account == _msgSender(), "AccessControl: can only renounce roles for self"); _revokeRole(role, account); } /** * @dev Grants `role` to `account`. * * If `account` had not been already granted `role`, emits a {RoleGranted} * event. Note that unlike {grantRole}, this function doesn't perform any * checks on the calling account. * * May emit a {RoleGranted} event. * * [WARNING] * ==== * This function should only be called from the constructor when setting * up the initial roles for the system. * * Using this function in any other way is effectively circumventing the admin * system imposed by {AccessControl}. * ==== * * NOTE: This function is deprecated in favor of {_grantRole}. */ function _setupRole(bytes32 role, address account) internal virtual { _grantRole(role, account); } /** * @dev Sets `adminRole` as ``role``'s admin role. * * Emits a {RoleAdminChanged} event. */ function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual { bytes32 previousAdminRole = getRoleAdmin(role); _roles[role].adminRole = adminRole; emit RoleAdminChanged(role, previousAdminRole, adminRole); } /** * @dev Grants `role` to `account`. * * Internal function without access restriction. * * May emit a {RoleGranted} event. */ function _grantRole(bytes32 role, address account) internal virtual { require(hasRole(DEFAULT_ADMIN_ROLE, _msgSender()), "AccessControl: must have ADMIN_ROLE"); if (!hasRole(role, account)) { _roles[role].members[account] = true; emit RoleGranted(role, account, _msgSender()); } } /** * @dev Grants `role` to `account`. * * Internal function without access restriction. * * May emit a {RoleGranted} event. */ function _grantAdminRole(address account) internal virtual { if (!hasRole(DEFAULT_ADMIN_ROLE, account)) { _roles[DEFAULT_ADMIN_ROLE].members[account] = true; emit RoleGranted(DEFAULT_ADMIN_ROLE, account, _msgSender()); } } /** * @dev Revokes `role` from `account`. * * Internal function without access restriction. * * May emit a {RoleRevoked} event. */ function _revokeRole(bytes32 role, address account) internal virtual { if (hasRole(role, account)) { _roles[role].members[account] = false; emit RoleRevoked(role, account, _msgSender()); } } } // OpenZeppelin Contracts v4.4.1 (access/IAccessControlEnumerable.sol) pragma solidity ^0.8.0; /** * @dev External interface of AccessControlEnumerable declared to support ERC165 detection. */ interface IAccessControlEnumerable is IAccessControl { /** * @dev Returns one of the accounts that have `role`. `index` must be a * value between 0 and {getRoleMemberCount}, non-inclusive. * * Role bearers are not sorted in any particular way, and their ordering may * change at any point. * * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure * you perform all queries on the same block. See the following * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post] * for more information. */ function getRoleMember(bytes32 role, uint256 index) external view returns (address); /** * @dev Returns the number of accounts that have `role`. Can be used * together with {getRoleMember} to enumerate all bearers of a role. */ function getRoleMemberCount(bytes32 role) external view returns (uint256); } // OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol) pragma solidity ^0.8.0; /** * @dev Contract module which allows children to implement an emergency stop * mechanism that can be triggered by an authorized account. * * This module is used through inheritance. It will make available the * modifiers `whenNotPaused` and `whenPaused`, which can be applied to * the functions of your contract. Note that they will not be pausable by * simply including this module, only once the modifiers are put in place. */ abstract contract Pausable is Context { /** * @dev Emitted when the pause is triggered by `account`. */ event Paused(address account); /** * @dev Emitted when the pause is lifted by `account`. */ event Unpaused(address account); bool private _paused; /** * @dev Initializes the contract in unpaused state. */ constructor() { _paused = false; } /** * @dev Modifier to make a function callable only when the contract is not paused. * * Requirements: * * - The contract must not be paused. */ modifier whenNotPaused() { _requireNotPaused(); _; } /** * @dev Modifier to make a function callable only when the contract is paused. * * Requirements: * * - The contract must be paused. */ modifier whenPaused() { _requirePaused(); _; } /** * @dev Returns true if the contract is paused, and false otherwise. */ function paused() public view virtual returns (bool) { return _paused; } /** * @dev Throws if the contract is paused. */ function _requireNotPaused() internal view virtual { require(!paused(), "Pausable: paused"); } /** * @dev Throws if the contract is not paused. */ function _requirePaused() internal view virtual { require(paused(), "Pausable: not paused"); } /** * @dev Triggers stopped state. * * Requirements: * * - The contract must not be paused. */ function _pause() internal virtual whenNotPaused { _paused = true; emit Paused(_msgSender()); } /** * @dev Returns to normal state. * * Requirements: * * - The contract must be paused. */ function _unpause() internal virtual whenPaused { _paused = false; emit Unpaused(_msgSender()); } } // 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 minted amount of tokens. */ function mintedSupply() external view returns (uint256); /** * @dev Returns the limit amount for a single coin transaction of tokens */ function mintLimitAmount() 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); } // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol) pragma solidity ^0.8.0; /** * @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); } // OpenZeppelin Contracts (last updated v4.5.0) (access/AccessControlEnumerable.sol) pragma solidity ^0.8.0; /** * @dev Extension of {AccessControl} that allows enumerating the members of each role. */ abstract contract AccessControlEnumerable is IAccessControlEnumerable, AccessControl { using EnumerableSet for EnumerableSet.AddressSet; mapping(bytes32 => EnumerableSet.AddressSet) private _roleMembers; /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) { return interfaceId == type(IAccessControlEnumerable).interfaceId || super.supportsInterface(interfaceId); } /** * @dev Returns one of the accounts that have `role`. `index` must be a * value between 0 and {getRoleMemberCount}, non-inclusive. * * Role bearers are not sorted in any particular way, and their ordering may * change at any point. * * WARNING: When using {getRoleMember} and {getRoleMemberCount}, make sure * you perform all queries on the same block. See the following * https://forum.openzeppelin.com/t/iterating-over-elements-on-enumerableset-in-openzeppelin-contracts/2296[forum post] * for more information. */ function getRoleMember(bytes32 role, uint256 index) public view virtual override returns (address) { return _roleMembers[role].at(index); } /** * @dev Returns the number of accounts that have `role`. Can be used * together with {getRoleMember} to enumerate all bearers of a role. */ function getRoleMemberCount(bytes32 role) public view virtual override returns (uint256) { return _roleMembers[role].length(); } /** * @dev Overload {_grantRole} to track enumerable memberships */ function _grantRole(bytes32 role, address account) internal virtual override { super._grantRole(role, account); _roleMembers[role].add(account); } /** * @dev Overload {_revokeRole} to track enumerable memberships */ function _revokeRole(bytes32 role, address account) internal virtual override { super._revokeRole(role, account); _roleMembers[role].remove(account); } } // OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/ERC20.sol) pragma solidity ^0.8.0; /** * @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.openzeppelin.com/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; uint256 private _mintedSupply; uint256 private _mintLimitAmount; 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_, uint256 totalSupply_) { _name = name_; _symbol = symbol_; _totalSupply = totalSupply_; } /** * @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 8; } /** * @dev See {IERC20-totalSupply}. */ function totalSupply() public view virtual override returns (uint256) { return _totalSupply; } /** * @dev See {IERC20-mintedSupply}. */ function mintedSupply() public view virtual override returns (uint256) { return _mintedSupply; } /** * @dev See {IERC20-mintedSupply}. */ function mintLimitAmount() public view virtual override returns (uint256) { return _mintLimitAmount; } /** * @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; // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by // decrementing then incrementing. _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"); require(amount <= _mintLimitAmount, "ERC20: error mint limit"); _beforeTokenTransfer(address(0), account, amount); require(_mintedSupply + amount <= _totalSupply, "ERC20: Exceeding the TotalSupply."); _mintedSupply += amount; unchecked { // Overflow not possible: balance + amount is at most TotalSupply + amount, which is checked above. _balances[account] += amount; } emit Transfer(address(0), account, amount); _afterTokenTransfer(address(0), account, amount); } /** * @dev SetMintLimitAmount */ function _setMintLimitAmount(uint256 limitAmount) internal virtual returns (bool) { _mintLimitAmount = limitAmount; return true; } /** * @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; // Overflow not possible: amount <= accountBalance <= mintedSupply. _mintedSupply -= 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 {} } // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol) pragma solidity ^0.8.0; /** * @dev Extension of {ERC20} that allows token holders to destroy both their own * tokens and those that they have an allowance for, in a way that can be * recognized off-chain (via event analysis). */ abstract contract ERC20Burnable is Context, ERC20 { /** * @dev Destroys `amount` tokens from the caller. * * See {ERC20-_burn}. */ function burn(uint256 amount) public virtual { _burn(_msgSender(), amount); } /** * @dev Destroys `amount` tokens from `account`, deducting from the caller's * allowance. * * See {ERC20-_burn} and {ERC20-allowance}. * * Requirements: * * - the caller must have allowance for ``accounts``'s tokens of at least * `amount`. */ function burnFrom(address account, uint256 amount) public virtual { _spendAllowance(account, _msgSender(), amount); _burn(account, amount); } } // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/ERC20Pausable.sol) pragma solidity ^0.8.0; /** * @dev ERC20 token with pausable token transfers, minting and burning. * * Useful for scenarios such as preventing trades until the end of an evaluation * period, or having an emergency switch for freezing all token transfers in the * event of a large bug. */ abstract contract ERC20Pausable is ERC20, Pausable { /** * @dev See {ERC20-_beforeTokenTransfer}. * * Requirements: * * - the contract must not be paused. */ function _beforeTokenTransfer( address from, address to, uint256 amount ) internal virtual override { super._beforeTokenTransfer(from, to, amount); require(!paused(), "ERC20Pausable: token transfer while paused"); } } // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/presets/ERC20PresetMinterPauser.sol) pragma solidity ^0.8.0; /** * @dev {ERC20} token, including: * * - ability for holders to burn (destroy) their tokens * - a minter role that allows for token minting (creation) * - a pauser role that allows to stop all token transfers * * This contract uses {AccessControl} to lock permissioned functions using the * different roles - head to its documentation for details. * * The account that deploys the contract will be granted the minter and pauser * roles, as well as the default admin role, which will let it grant both minter * and pauser roles to other accounts. * * _Deprecated in favor of https://wizard.openzeppelin.com/[Contracts Wizard]._ */ contract ERC20PresetMinterPauser is Context, AccessControlEnumerable, ERC20Burnable, ERC20Pausable { bytes32 public constant MINTER_ROLE = keccak256("MINTER_ROLE"); bytes32 public constant PAUSER_ROLE = keccak256("PAUSER_ROLE"); /** * @dev Grants `DEFAULT_ADMIN_ROLE`, `MINTER_ROLE` and `PAUSER_ROLE` to the * account that deploys the contract. * * See {ERC20-constructor}. */ constructor(string memory name, string memory symbol, uint256 totalSupply) ERC20(name, symbol, totalSupply) { _grantAdminRole(_msgSender()); _setupRole(MINTER_ROLE, _msgSender()); _setupRole(PAUSER_ROLE, _msgSender()); } /** * @dev Creates `amount` new tokens for `to`. * * See {ERC20-_mint}. * * Requirements: * * - the caller must have the `MINTER_ROLE`. */ function setMintLimitAmount(uint256 amount) public virtual { require(hasRole(DEFAULT_ADMIN_ROLE, _msgSender()), "ERC20PresetMinterPauser: must have ADMIN_ROLE"); _setMintLimitAmount(amount); } /** * @dev Set limitForMint * * See {ERC20- _setMintLimit}. * * Requirements: * * - the caller must have the `MINTER_ROLE`. */ function mint(address to, uint256 amount) public virtual { require(hasRole(MINTER_ROLE, _msgSender()), "ERC20PresetMinterPauser: must have minter role to mint"); _mint(to, amount); } /** * @dev Pauses all token transfers. * * See {ERC20Pausable} and {Pausable-_pause}. * * Requirements: * * - the caller must have the `PAUSER_ROLE`. */ function pause() public virtual { require(hasRole(PAUSER_ROLE, _msgSender()), "ERC20PresetMinterPauser: must have pauser role to pause"); _pause(); } /** * @dev Unpauses all token transfers. * * See {ERC20Pausable} and {Pausable-_unpause}. * * Requirements: * * - the caller must have the `PAUSER_ROLE`. */ function unpause() public virtual { require(hasRole(PAUSER_ROLE, _msgSender()), "ERC20PresetMinterPauser: must have pauser role to unpause"); _unpause(); } function _beforeTokenTransfer( address from, address to, uint256 amount ) internal virtual override(ERC20, ERC20Pausable) { super._beforeTokenTransfer(from, to, amount); } }