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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
import { Lib_AddressManager } from "./Lib_AddressManager.sol";
/**
* @title Lib_ResolvedDelegateProxy
*/
contract Lib_ResolvedDelegateProxy {
/*************
* Variables *
*************/
// Using mappings to store fields to avoid overwriting storage slots in the
// implementation contract. For example, instead of storing these fields at
// storage slot `0` & `1`, they are stored at `keccak256(key + slot)`.
// See: https://solidity.readthedocs.io/en/v0.7.0/internals/layout_in_storage.html
// NOTE: Do not use this code in your own contract system.
// There is a known flaw in this contract, and we will remove it from the repository
// in the near future. Due to the very limited way that we are using it, this flaw is
// not an issue in our system.
mapping(address => string) private implementationName;
mapping(address => Lib_AddressManager) private addressManager;
/***************
* Constructor *
***************/
/**
* @param _libAddressManager Address of the Lib_AddressManager.
* @param _implementationName implementationName of the contract to proxy to.
*/
constructor(address _libAddressManager, string memory _implementationName) {
addressManager[address(this)] = Lib_AddressManager(_libAddressManager);
implementationName[address(this)] = _implementationName;
}
/*********************
* Fallback Function *
*********************/
fallback() external payable {
address target = addressManager[address(this)].getAddress(
(implementationName[address(this)])
);
require(target != address(0), "Target address must be initialized.");
// slither-disable-next-line controlled-delegatecall
(bool success, bytes memory returndata) = target.delegatecall(msg.data);
if (success == true) {
assembly {
return(add(returndata, 0x20), mload(returndata))
}
} else {
assembly {
revert(add(returndata, 0x20), mload(returndata))
}
}
}
}