TransparentUpgradeableProxy

< {{
  "language": "Solidity",
  "settings": {
    "evmVersion": "istanbul",
    "libraries": {},
    "metadata": {
      "bytecodeHash": "ipfs",
      "useLiteralContent": true
    },
    "optimizer": {
      "enabled": true,
      "runs": 100
    },
    "remappings": [],
    "outputSelection": {
      "*": {
        "*": [
          "evm.bytecode",
          "evm.deployedBytecode",
          "abi"
        ]
      }
    }
  },
  "sources": {
    "@openzeppelin/contracts/proxy/Proxy.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.0 <0.8.0;\n\n/**\n * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM\n * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to\n * be specified by overriding the virtual {_implementation} function.\n *\n * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a\n * different contract through the {_delegate} function.\n *\n * The success and return data of the delegated call will be returned back to the caller of the proxy.\n */\nabstract contract Proxy {\n    /**\n     * @dev Delegates the current call to `implementation`.\n     *\n     * This function does not return to its internall call site, it will return directly to the external caller.\n     */\n    function _delegate(address implementation) internal virtual {\n        // solhint-disable-next-line no-inline-assembly\n        assembly {\n            // Copy msg.data. We take full control of memory in this inline assembly\n            // block because it will not return to Solidity code. We overwrite the\n            // Solidity scratch pad at memory position 0.\n            calldatacopy(0, 0, calldatasize())\n\n            // Call the implementation.\n            // out and outsize are 0 because we don't know the size yet.\n            let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)\n\n            // Copy the returned data.\n            returndatacopy(0, 0, returndatasize())\n\n            switch result\n            // delegatecall returns 0 on error.\n            case 0 { revert(0, returndatasize()) }\n            default { return(0, returndatasize()) }\n        }\n    }\n\n    /**\n     * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function\n     * and {_fallback} should delegate.\n     */\n    function _implementation() internal view virtual returns (address);\n\n    /**\n     * @dev Delegates the current call to the address returned by `_implementation()`.\n     *\n     * This function does not return to its internall call site, it will return directly to the external caller.\n     */\n    function _fallback() internal virtual {\n        _beforeFallback();\n        _delegate(_implementation());\n    }\n\n    /**\n     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other\n     * function in the contract matches the call data.\n     */\n    fallback () external payable virtual {\n        _fallback();\n    }\n\n    /**\n     * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data\n     * is empty.\n     */\n    receive () external payable virtual {\n        _fallback();\n    }\n\n    /**\n     * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`\n     * call, or as part of the Solidity `fallback` or `receive` functions.\n     *\n     * If overriden should call `super._beforeFallback()`.\n     */\n    function _beforeFallback() internal virtual {\n    }\n}\n"
    },
    "@openzeppelin/contracts/proxy/TransparentUpgradeableProxy.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.0 <0.8.0;\n\nimport \"./UpgradeableProxy.sol\";\n\n/**\n * @dev This contract implements a proxy that is upgradeable by an admin.\n *\n * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector\n * clashing], which can potentially be used in an attack, this contract uses the\n * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two\n * things that go hand in hand:\n *\n * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if\n * that call matches one of the admin functions exposed by the proxy itself.\n * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the\n * implementation. If the admin tries to call a function on the implementation it will fail with an error that says\n * \"admin cannot fallback to proxy target\".\n *\n * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing\n * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due\n * to sudden errors when trying to call a function from the proxy implementation.\n *\n * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,\n * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.\n */\ncontract TransparentUpgradeableProxy is UpgradeableProxy {\n    /**\n     * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and\n     * optionally initialized with `_data` as explained in {UpgradeableProxy-constructor}.\n     */\n    constructor(address _logic, address admin_, bytes memory _data) public payable UpgradeableProxy(_logic, _data) {\n        assert(_ADMIN_SLOT == bytes32(uint256(keccak256(\"eip1967.proxy.admin\")) - 1));\n        _setAdmin(admin_);\n    }\n\n    /**\n     * @dev Emitted when the admin account has changed.\n     */\n    event AdminChanged(address previousAdmin, address newAdmin);\n\n    /**\n     * @dev Storage slot with the admin of the contract.\n     * This is the keccak-256 hash of \"eip1967.proxy.admin\" subtracted by 1, and is\n     * validated in the constructor.\n     */\n    bytes32 private constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;\n\n    /**\n     * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.\n     */\n    modifier ifAdmin() {\n        if (msg.sender == _admin()) {\n            _;\n        } else {\n            _fallback();\n        }\n    }\n\n    /**\n     * @dev Returns the current admin.\n     *\n     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.\n     *\n     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the\n     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.\n     * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`\n     */\n    function admin() external ifAdmin returns (address admin_) {\n        admin_ = _admin();\n    }\n\n    /**\n     * @dev Returns the current implementation.\n     *\n     * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.\n     *\n     * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the\n     * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.\n     * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`\n     */\n    function implementation() external ifAdmin returns (address implementation_) {\n        implementation_ = _implementation();\n    }\n\n    /**\n     * @dev Changes the admin of the proxy.\n     *\n     * Emits an {AdminChanged} event.\n     *\n     * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.\n     */\n    function changeAdmin(address newAdmin) external virtual ifAdmin {\n        require(newAdmin != address(0), \"TransparentUpgradeableProxy: new admin is the zero address\");\n        emit AdminChanged(_admin(), newAdmin);\n        _setAdmin(newAdmin);\n    }\n\n    /**\n     * @dev Upgrade the implementation of the proxy.\n     *\n     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.\n     */\n    function upgradeTo(address newImplementation) external virtual ifAdmin {\n        _upgradeTo(newImplementation);\n    }\n\n    /**\n     * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified\n     * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the\n     * proxied contract.\n     *\n     * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.\n     */\n    function upgradeToAndCall(address newImplementation, bytes calldata data) external payable virtual ifAdmin {\n        _upgradeTo(newImplementation);\n        Address.functionDelegateCall(newImplementation, data);\n    }\n\n    /**\n     * @dev Returns the current admin.\n     */\n    function _admin() internal view virtual returns (address adm) {\n        bytes32 slot = _ADMIN_SLOT;\n        // solhint-disable-next-line no-inline-assembly\n        assembly {\n            adm := sload(slot)\n        }\n    }\n\n    /**\n     * @dev Stores a new address in the EIP1967 admin slot.\n     */\n    function _setAdmin(address newAdmin) private {\n        bytes32 slot = _ADMIN_SLOT;\n\n        // solhint-disable-next-line no-inline-assembly\n        assembly {\n            sstore(slot, newAdmin)\n        }\n    }\n\n    /**\n     * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.\n     */\n    function _beforeFallback() internal virtual override {\n        require(msg.sender != _admin(), \"TransparentUpgradeableProxy: admin cannot fallback to proxy target\");\n        super._beforeFallback();\n    }\n}\n"
    },
    "@openzeppelin/contracts/proxy/UpgradeableProxy.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.0 <0.8.0;\n\nimport \"./Proxy.sol\";\nimport \"../utils/Address.sol\";\n\n/**\n * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an\n * implementation address that can be changed. This address is stored in storage in the location specified by\n * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the\n * implementation behind the proxy.\n *\n * Upgradeability is only provided internally through {_upgradeTo}. For an externally upgradeable proxy see\n * {TransparentUpgradeableProxy}.\n */\ncontract UpgradeableProxy is Proxy {\n    /**\n     * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.\n     *\n     * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded\n     * function call, and allows initializating the storage of the proxy like a Solidity constructor.\n     */\n    constructor(address _logic, bytes memory _data) public payable {\n        assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256(\"eip1967.proxy.implementation\")) - 1));\n        _setImplementation(_logic);\n        if(_data.length > 0) {\n            Address.functionDelegateCall(_logic, _data);\n        }\n    }\n\n    /**\n     * @dev Emitted when the implementation is upgraded.\n     */\n    event Upgraded(address indexed implementation);\n\n    /**\n     * @dev Storage slot with the address of the current implementation.\n     * This is the keccak-256 hash of \"eip1967.proxy.implementation\" subtracted by 1, and is\n     * validated in the constructor.\n     */\n    bytes32 private constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;\n\n    /**\n     * @dev Returns the current implementation address.\n     */\n    function _implementation() internal view virtual override returns (address impl) {\n        bytes32 slot = _IMPLEMENTATION_SLOT;\n        // solhint-disable-next-line no-inline-assembly\n        assembly {\n            impl := sload(slot)\n        }\n    }\n\n    /**\n     * @dev Upgrades the proxy to a new implementation.\n     *\n     * Emits an {Upgraded} event.\n     */\n    function _upgradeTo(address newImplementation) internal virtual {\n        _setImplementation(newImplementation);\n        emit Upgraded(newImplementation);\n    }\n\n    /**\n     * @dev Stores a new address in the EIP1967 implementation slot.\n     */\n    function _setImplementation(address newImplementation) private {\n        require(Address.isContract(newImplementation), \"UpgradeableProxy: new implementation is not a contract\");\n\n        bytes32 slot = _IMPLEMENTATION_SLOT;\n\n        // solhint-disable-next-line no-inline-assembly\n        assembly {\n            sstore(slot, newImplementation)\n        }\n    }\n}\n"
    },
    "@openzeppelin/contracts/utils/Address.sol": {
      "content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.2 <0.8.0;\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    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize, which returns 0 for contracts in\n        // construction, since the code is only stored at the end of the\n        // constructor execution.\n\n        uint256 size;\n        // solhint-disable-next-line no-inline-assembly\n        assembly { size := extcodesize(account) }\n        return size > 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        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\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 functionCall(target, data, \"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(address target, bytes memory data, string memory errorMessage) 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(address target, bytes memory data, uint256 value) 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(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n        require(address(this).balance >= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.call{ value: value }(data);\n        return _verifyCallResult(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(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return _verifyCallResult(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(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\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\n                // solhint-disable-next-line no-inline-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}\n"
    }
  }
}} <