// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (token/ERC1155/utils/ERC1155Holder.sol) pragma solidity ^0.8.0; import "./ERC1155ReceiverUpgradeable.sol"; import "../../../proxy/utils/Initializable.sol"; /** * Simple implementation of `ERC1155Receiver` that will allow a contract to hold ERC1155 tokens. * * IMPORTANT: When inheriting this contract, you must include a way to use the received tokens, otherwise they will be * stuck. * * @dev _Available since v3.1._ */ contract ERC1155HolderUpgradeable is Initializable, ERC1155ReceiverUpgradeable { function __ERC1155Holder_init() internal onlyInitializing { } function __ERC1155Holder_init_unchained() internal onlyInitializing { } function onERC1155Received( address, address, uint256, uint256, bytes memory ) public virtual override returns (bytes4) { return this.onERC1155Received.selector; } function onERC1155BatchReceived( address, address, uint256[] memory, uint256[] memory, bytes memory ) public virtual override returns (bytes4) { return this.onERC1155BatchReceived.selector; } /** * This empty reserved space is put in place to allow future versions to add new * variables without shifting down storage in the inheritance chain. * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps */ uint256[50] private __gap; }