// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol) pragma solidity ^0.8.20; import {Context} from "../utils/Context.sol"; /** * @dev Contract module which provides a basic access control mechanism, where * there is an account (an owner) that can be granted exclusive access to * specific functions. * * The initial owner is set to the address provided by the deployer. This can * later be changed with {transferOwnership}. * * This module is used through inheritance. It will make available the modifier * `onlyOwner`, which can be applied to your functions to restrict their use to * the owner. */ abstract contract Ownable is Context { address private _owner; /** * @dev The caller account is not authorized to perform an operation. */ error OwnableUnauthorizedAccount(address account); /** * @dev The owner is not a valid owner account. (eg. `address(0)`) */ error OwnableInvalidOwner(address owner); event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); /** * @dev Initializes the contract setting the address provided by the deployer as the initial owner. */ constructor(address initialOwner) { _transferOwnership(initialOwner); } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { _checkOwner(); _; } /** * @dev Returns the address of the current owner. */ function owner() public view virtual returns (address) { return _owner; } /** * @dev Throws if the sender is not the owner. */ function _checkOwner() internal view virtual { if (owner() != _msgSender()) { revert OwnableUnauthorizedAccount(_msgSender()); } } /** * @dev Leaves the contract without owner. It will not be possible to call * `onlyOwner` functions. Can only be called by the current owner. * * NOTE: Renouncing ownership will leave the contract without an owner, * thereby disabling any functionality that is only available to the owner. */ function renounceOwnership() public virtual onlyOwner { _transferOwnership(address(0)); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Can only be called by the current owner. */ function transferOwnership(address newOwner) public virtual onlyOwner { if (newOwner == address(0)) { revert OwnableInvalidOwner(address(0)); } _transferOwnership(newOwner); } /** * @dev Transfers ownership of the contract to a new account (`newOwner`). * Internal function without access restriction. */ function _transferOwnership(address newOwner) internal virtual { address oldOwner = _owner; _owner = newOwner; emit OwnershipTransferred(oldOwner, newOwner); } }