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May 5, 2023 19:28
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Permissioned Re-entrancyGuard with facility ot enable and disable re-entrancy call within the contract
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// SPDX-License-Identifier: MIT | |
// OpenZeppelin Contracts (last updated v4.8.0) (security/ReentrancyGuard.sol) | |
pragma solidity ^0.8.0; | |
/** | |
* @dev Contract module that helps prevent reentrant calls to a function. | |
* | |
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier | |
* available, which can be applied to functions to make sure there are no nested | |
* (reentrant) calls to them. | |
* | |
* Note that because there is a single `nonReentrant` guard, functions marked as | |
* `nonReentrant` may not call one another. This can be worked around by making | |
* those functions `private`, and then adding `external` `nonReentrant` entry | |
* points to them. | |
* | |
* TIP: If you would like to learn more about reentrancy and alternative ways | |
* to protect against it, check out our blog post | |
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul]. | |
* | |
* NOTE: Permissioned reentrancy enables re-entrant calls to be called in a permissioned mode | |
*/ | |
abstract contract ReentrancyGuardPermissioned { | |
// Booleans are more expensive than uint256 or any type that takes up a full | |
// word because each write operation emits an extra SLOAD to first read the | |
// slot's contents, replace the bits taken up by the boolean, and then write | |
// back. This is the compiler's defense against contract upgrades and | |
// pointer aliasing, and it cannot be disabled. | |
// The values being non-zero value makes deployment a bit more expensive, | |
// but in exchange the refund on every call to nonReentrant will be lower in | |
// amount. Since refunds are capped to a percentage of the total | |
// transaction's gas, it is best to keep them low in cases like this one, to | |
// increase the likelihood of the full refund coming into effect. | |
uint256 private constant _NOT_ENTERED = 1; | |
uint256 private constant _ENTERED = 2; | |
bool private _permit; | |
uint256 private _status; | |
constructor() { | |
_status = _NOT_ENTERED; | |
} | |
/** | |
* @dev Prevents a contract from calling itself, directly or indirectly. | |
* Calling a `nonReentrant` function from another `nonReentrant` | |
* function is not supported. It is possible to prevent this from happening | |
* by making the `nonReentrant` function external, and making it call a | |
* `private` function that does the actual work. | |
*/ | |
modifier nonReentrant() { | |
if (_permit){ | |
unsetSetter(); | |
}else{ | |
_nonReentrantBefore(); | |
_; | |
_nonReentrantAfter(); | |
} | |
} | |
function _nonReentrantBefore() private { | |
// On the first call to nonReentrant, _status will be _NOT_ENTERED | |
require(_status != _ENTERED, "ReentrancyGuard: reentrant call"); | |
// Any calls to nonReentrant after this point will fail | |
_status = _ENTERED; | |
} | |
function _nonReentrantAfter() private { | |
// By storing the original value once again, a refund is triggered (see | |
// https://eips.ethereum.org/EIPS/eip-2200) | |
_status = _NOT_ENTERED; | |
} | |
/** | |
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a | |
* `nonReentrant` function in the call stack. | |
*/ | |
function _reentrancyGuardEntered() internal view returns (bool) { | |
return _status == _ENTERED; | |
} | |
/** | |
* @dev Enable Permit for the call done to be re entrant once | |
*/ | |
function setPermit() internal { | |
_permit = true; | |
} | |
/** | |
* @dev Disable Permit for the call and enable normal re-entrancy guard. | |
*/ | |
function unsetPermit() internal { | |
_permit = false; | |
} | |
} |
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Wouldn't be more logical to declare 2
uint128
in order to pack it into 32 bytes? Correct me if I am wrong here.https://gist.github.com/18dew/6cfcc6eace110291df13c7be34e8c5eb#file-reentrancyguardpermissioned-sol-L36-L37