3e6c86392c
Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com> Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com> Co-authored-by: Francisco Giordano <fg@frang.io> Co-authored-by: Ernesto García <ernestognw@gmail.com> Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com> Co-authored-by: Eric Lau <ericglau@outlook.com> Co-authored-by: Hadrien Croubois <hadrien.croubois@gmail.com>
70 lines
2.6 KiB
Solidity
70 lines
2.6 KiB
Solidity
// SPDX-License-Identifier: MIT
|
|
// OpenZeppelin Contracts (last updated v5.0.0) (proxy/Proxy.sol)
|
|
|
|
pragma solidity ^0.8.20;
|
|
|
|
/**
|
|
* @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
|
|
* instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
|
|
* be specified by overriding the virtual {_implementation} function.
|
|
*
|
|
* Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
|
|
* different contract through the {_delegate} function.
|
|
*
|
|
* The success and return data of the delegated call will be returned back to the caller of the proxy.
|
|
*/
|
|
abstract contract Proxy {
|
|
/**
|
|
* @dev Delegates the current call to `implementation`.
|
|
*
|
|
* This function does not return to its internal call site, it will return directly to the external caller.
|
|
*/
|
|
function _delegate(address implementation) internal virtual {
|
|
assembly {
|
|
// Copy msg.data. We take full control of memory in this inline assembly
|
|
// block because it will not return to Solidity code. We overwrite the
|
|
// Solidity scratch pad at memory position 0.
|
|
calldatacopy(0, 0, calldatasize())
|
|
|
|
// Call the implementation.
|
|
// out and outsize are 0 because we don't know the size yet.
|
|
let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
|
|
|
|
// Copy the returned data.
|
|
returndatacopy(0, 0, returndatasize())
|
|
|
|
switch result
|
|
// delegatecall returns 0 on error.
|
|
case 0 {
|
|
revert(0, returndatasize())
|
|
}
|
|
default {
|
|
return(0, returndatasize())
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @dev This is a virtual function that should be overridden so it returns the address to which the fallback
|
|
* function and {_fallback} should delegate.
|
|
*/
|
|
function _implementation() internal view virtual returns (address);
|
|
|
|
/**
|
|
* @dev Delegates the current call to the address returned by `_implementation()`.
|
|
*
|
|
* This function does not return to its internal call site, it will return directly to the external caller.
|
|
*/
|
|
function _fallback() internal virtual {
|
|
_delegate(_implementation());
|
|
}
|
|
|
|
/**
|
|
* @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
|
|
* function in the contract matches the call data.
|
|
*/
|
|
fallback() external payable virtual {
|
|
_fallback();
|
|
}
|
|
}
|