Description:
Multi-signature wallet contract requiring multiple confirmations for transaction execution.
Blockchain: Ethereum
Source Code: View Code On The Blockchain
Solidity Source Code:
{{
"language": "Solidity",
"settings": {
"evmVersion": "cancun",
"optimizer": {
"enabled": true,
"runs": 200
},
"outputSelection": {
"*": {
"*": [
"evm.bytecode",
"evm.deployedBytecode",
"devdoc",
"userdoc",
"metadata",
"abi"
]
}
},
"remappings": [
"project/:@openzeppelin/contracts-upgradeable/=npm/@openzeppelin/contracts-upgradeable@5.4.0/",
"project/:@openzeppelin/contracts/=npm/@openzeppelin/contracts@5.4.0/",
"project/:@openzeppelin/contracts/=npm/@openzeppelin/contracts@5.4.0/"
],
"viaIR": true
},
"sources": {
"npm/@openzeppelin/contracts-upgradeable@5.4.0/proxy/utils/Initializable.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.3.0) (proxy/utils/Initializable.sol)
pragma solidity ^0.8.20;
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
* case an upgrade adds a module that needs to be initialized.
*
* For example:
*
* [.hljs-theme-light.nopadding]
* ```solidity
* contract MyToken is ERC20Upgradeable {
* function initialize() initializer public {
* __ERC20_init("MyToken", "MTK");
* }
* }
*
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
* function initializeV2() reinitializer(2) public {
* __ERC20Permit_init("MyToken");
* }
* }
* ```
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*
* [CAUTION]
* ====
* Avoid leaving a contract uninitialized.
*
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
*
* [.hljs-theme-light.nopadding]
* ```
* /// @custom:oz-upgrades-unsafe-allow constructor
* constructor() {
* _disableInitializers();
* }
* ```
* ====
*/
abstract contract Initializable {
/**
* @dev Storage of the initializable contract.
*
* It's implemented on a custom ERC-7201 namespace to reduce the risk of storage collisions
* when using with upgradeable contracts.
*
* @custom:storage-location erc7201:openzeppelin.storage.Initializable
*/
struct InitializableStorage {
/**
* @dev Indicates that the contract has been initialized.
*/
uint64 _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool _initializing;
}
// keccak256(abi.encode(uint256(keccak256("openzeppelin.storage.Initializable")) - 1)) & ~bytes32(uint256(0xff))
bytes32 private constant INITIALIZABLE_STORAGE = 0xf0c57e16840df040f15088dc2f81fe391c3923bec73e23a9662efc9c229c6a00;
/**
* @dev The contract is already initialized.
*/
error InvalidInitialization();
/**
* @dev The contract is not initializing.
*/
error NotInitializing();
/**
* @dev Triggered when the contract has been initialized or reinitialized.
*/
event Initialized(uint64 version);
/**
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
* `onlyInitializing` functions can be used to initialize parent contracts.
*
* Similar to `reinitializer(1)`, except that in the context of a constructor an `initializer` may be invoked any
* number of times. This behavior in the constructor can be useful during testing and is not expected to be used in
* production.
*
* Emits an {Initialized} event.
*/
modifier initializer() {
// solhint-disable-next-line var-name-mixedcase
InitializableStorage storage $ = _getInitializableStorage();
// Cache values to avoid duplicated sloads
bool isTopLevelCall = !$._initializing;
uint64 initialized = $._initialized;
// Allowed calls:
// - initialSetup: the contract is not in the initializing state and no previous version was
// initialized
// - construction: the contract is initialized at version 1 (no reinitialization) and the
// current contract is just being deployed
bool initialSetup = initialized == 0 && isTopLevelCall;
bool construction = initialized == 1 && address(this).code.length == 0;
if (!initialSetup && !construction) {
revert InvalidInitialization();
}
$._initialized = 1;
if (isTopLevelCall) {
$._initializing = true;
}
_;
if (isTopLevelCall) {
$._initializing = false;
emit Initialized(1);
}
}
/**
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
* used to initialize parent contracts.
*
* A reinitializer may be used after the original initialization step. This is essential to configure modules that
* are added through upgrades and that require initialization.
*
* When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
* cannot be nested. If one is invoked in the context of another, execution will revert.
*
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
* a contract, executing them in the right order is up to the developer or operator.
*
* WARNING: Setting the version to 2**64 - 1 will prevent any future reinitialization.
*
* Emits an {Initialized} event.
*/
modifier reinitializer(uint64 version) {
// solhint-disable-next-line var-name-mixedcase
InitializableStorage storage $ = _getInitializableStorage();
if ($._initializing || $._initialized >= version) {
revert InvalidInitialization();
}
$._initialized = version;
$._initializing = true;
_;
$._initializing = false;
emit Initialized(version);
}
/**
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
* {initializer} and {reinitializer} modifiers, directly or indirectly.
*/
modifier onlyInitializing() {
_checkInitializing();
_;
}
/**
* @dev Reverts if the contract is not in an initializing state. See {onlyInitializing}.
*/
function _checkInitializing() internal view virtual {
if (!_isInitializing()) {
revert NotInitializing();
}
}
/**
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called
* through proxies.
*
* Emits an {Initialized} event the first time it is successfully executed.
*/
function _disableInitializers() internal virtual {
// solhint-disable-next-line var-name-mixedcase
InitializableStorage storage $ = _getInitializableStorage();
if ($._initializing) {
revert InvalidInitialization();
}
if ($._initialized != type(uint64).max) {
$._initialized = type(uint64).max;
emit Initialized(type(uint64).max);
}
}
/**
* @dev Returns the highest version that has been initialized. See {reinitializer}.
*/
function _getInitializedVersion() internal view returns (uint64) {
return _getInitializableStorage()._initialized;
}
/**
* @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
*/
function _isInitializing() internal view returns (bool) {
return _getInitializableStorage()._initializing;
}
/**
* @dev Pointer to storage slot. Allows integrators to override it with a custom storage location.
*
* NOTE: Consider following the ERC-7201 formula to derive storage locations.
*/
function _initializableStorageSlot() internal pure virtual returns (bytes32) {
return INITIALIZABLE_STORAGE;
}
/**
* @dev Returns a pointer to the storage namespace.
*/
// solhint-disable-next-line var-name-mixedcase
function _getInitializableStorage() private pure returns (InitializableStorage storage $) {
bytes32 slot = _initializableStorageSlot();
assembly {
$.slot := slot
}
}
}
"
},
"npm/@openzeppelin/contracts@5.4.0/access/Ownable.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
pragma solidity ^0.8.20;
import {Context} from "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* The initial owner is set to the address provided by the deployer. This can
* later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
/**
* @dev The caller account is not authorized to perform an operation.
*/
error OwnableUnauthorizedAccount(address account);
/**
* @dev The owner is not a valid owner account. (eg. `address(0)`)
*/
error OwnableInvalidOwner(address owner);
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the address provided by the deployer as the initial owner.
*/
constructor(address initialOwner) {
if (initialOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(initialOwner);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
if (owner() != _msgSender()) {
revert OwnableUnauthorizedAccount(_msgSender());
}
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
if (newOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
"
},
"npm/@openzeppelin/contracts@5.4.0/interfaces/draft-IERC6093.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/draft-IERC6093.sol)
pragma solidity >=0.8.4;
/**
* @dev Standard ERC-20 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-20 tokens.
*/
interface IERC20Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC20InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC20InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
* @param spender Address that may be allowed to operate on tokens without being their owner.
* @param allowance Amount of tokens a `spender` is allowed to operate with.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC20InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `spender` to be approved. Used in approvals.
* @param spender Address that may be allowed to operate on tokens without being their owner.
*/
error ERC20InvalidSpender(address spender);
}
/**
* @dev Standard ERC-721 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-721 tokens.
*/
interface IERC721Errors {
/**
* @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in ERC-20.
* Used in balance queries.
* @param owner Address of the current owner of a token.
*/
error ERC721InvalidOwner(address owner);
/**
* @dev Indicates a `tokenId` whose `owner` is the zero address.
* @param tokenId Identifier number of a token.
*/
error ERC721NonexistentToken(uint256 tokenId);
/**
* @dev Indicates an error related to the ownership over a particular token. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param tokenId Identifier number of a token.
* @param owner Address of the current owner of a token.
*/
error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC721InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC721InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param tokenId Identifier number of a token.
*/
error ERC721InsufficientApproval(address operator, uint256 tokenId);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC721InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC721InvalidOperator(address operator);
}
/**
* @dev Standard ERC-1155 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-1155 tokens.
*/
interface IERC1155Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
* @param tokenId Identifier number of a token.
*/
error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC1155InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC1155InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param owner Address of the current owner of a token.
*/
error ERC1155MissingApprovalForAll(address operator, address owner);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC1155InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC1155InvalidOperator(address operator);
/**
* @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
* Used in batch transfers.
* @param idsLength Length of the array of token identifiers
* @param valuesLength Length of the array of token amounts
*/
error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}
"
},
"npm/@openzeppelin/contracts@5.4.0/token/ERC721/ERC721.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/ERC721.sol)
pragma solidity ^0.8.20;
import {IERC721} from "./IERC721.sol";
import {IERC721Metadata} from "./extensions/IERC721Metadata.sol";
import {ERC721Utils} from "./utils/ERC721Utils.sol";
import {Context} from "../../utils/Context.sol";
import {Strings} from "../../utils/Strings.sol";
import {IERC165, ERC165} from "../../utils/introspection/ERC165.sol";
import {IERC721Errors} from "../../interfaces/draft-IERC6093.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC-721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/
abstract contract ERC721 is Context, ERC165, IERC721, IERC721Metadata, IERC721Errors {
using Strings for uint256;
// Token name
string private _name;
// Token symbol
string private _symbol;
mapping(uint256 tokenId => address) private _owners;
mapping(address owner => uint256) private _balances;
mapping(uint256 tokenId => address) private _tokenApprovals;
mapping(address owner => mapping(address operator => bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/// @inheritdoc IERC165
function supportsInterface(bytes4 interfaceId) public view virtual override(ERC165, IERC165) returns (bool) {
return
interfaceId == type(IERC721).interfaceId ||
interfaceId == type(IERC721Metadata).interfaceId ||
super.supportsInterface(interfaceId);
}
/// @inheritdoc IERC721
function balanceOf(address owner) public view virtual returns (uint256) {
if (owner == address(0)) {
revert ERC721InvalidOwner(address(0));
}
return _balances[owner];
}
/// @inheritdoc IERC721
function ownerOf(uint256 tokenId) public view virtual returns (address) {
return _requireOwned(tokenId);
}
/// @inheritdoc IERC721Metadata
function name() public view virtual returns (string memory) {
return _name;
}
/// @inheritdoc IERC721Metadata
function symbol() public view virtual returns (string memory) {
return _symbol;
}
/// @inheritdoc IERC721Metadata
function tokenURI(uint256 tokenId) public view virtual returns (string memory) {
_requireOwned(tokenId);
string memory baseURI = _baseURI();
return bytes(baseURI).length > 0 ? string.concat(baseURI, tokenId.toString()) : "";
}
/**
* @dev Base URI for computing {tokenURI}. If set, the resulting URI for each
* token will be the concatenation of the `baseURI` and the `tokenId`. Empty
* by default, can be overridden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return "";
}
/// @inheritdoc IERC721
function approve(address to, uint256 tokenId) public virtual {
_approve(to, tokenId, _msgSender());
}
/// @inheritdoc IERC721
function getApproved(uint256 tokenId) public view virtual returns (address) {
_requireOwned(tokenId);
return _getApproved(tokenId);
}
/// @inheritdoc IERC721
function setApprovalForAll(address operator, bool approved) public virtual {
_setApprovalForAll(_msgSender(), operator, approved);
}
/// @inheritdoc IERC721
function isApprovedForAll(address owner, address operator) public view virtual returns (bool) {
return _operatorApprovals[owner][operator];
}
/// @inheritdoc IERC721
function transferFrom(address from, address to, uint256 tokenId) public virtual {
if (to == address(0)) {
revert ERC721InvalidReceiver(address(0));
}
// Setting an "auth" arguments enables the `_isAuthorized` check which verifies that the token exists
// (from != 0). Therefore, it is not needed to verify that the return value is not 0 here.
address previousOwner = _update(to, tokenId, _msgSender());
if (previousOwner != from) {
revert ERC721IncorrectOwner(from, tokenId, previousOwner);
}
}
/// @inheritdoc IERC721
function safeTransferFrom(address from, address to, uint256 tokenId) public {
safeTransferFrom(from, to, tokenId, "");
}
/// @inheritdoc IERC721
function safeTransferFrom(address from, address to, uint256 tokenId, bytes memory data) public virtual {
transferFrom(from, to, tokenId);
ERC721Utils.checkOnERC721Received(_msgSender(), from, to, tokenId, data);
}
/**
* @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist
*
* IMPORTANT: Any overrides to this function that add ownership of tokens not tracked by the
* core ERC-721 logic MUST be matched with the use of {_increaseBalance} to keep balances
* consistent with ownership. The invariant to preserve is that for any address `a` the value returned by
* `balanceOf(a)` must be equal to the number of tokens such that `_ownerOf(tokenId)` is `a`.
*/
function _ownerOf(uint256 tokenId) internal view virtual returns (address) {
return _owners[tokenId];
}
/**
* @dev Returns the approved address for `tokenId`. Returns 0 if `tokenId` is not minted.
*/
function _getApproved(uint256 tokenId) internal view virtual returns (address) {
return _tokenApprovals[tokenId];
}
/**
* @dev Returns whether `spender` is allowed to manage `owner`'s tokens, or `tokenId` in
* particular (ignoring whether it is owned by `owner`).
*
* WARNING: This function assumes that `owner` is the actual owner of `tokenId` and does not verify this
* assumption.
*/
function _isAuthorized(address owner, address spender, uint256 tokenId) internal view virtual returns (bool) {
return
spender != address(0) &&
(owner == spender || isApprovedForAll(owner, spender) || _getApproved(tokenId) == spender);
}
/**
* @dev Checks if `spender` can operate on `tokenId`, assuming the provided `owner` is the actual owner.
* Reverts if:
* - `spender` does not have approval from `owner` for `tokenId`.
* - `spender` does not have approval to manage all of `owner`'s assets.
*
* WARNING: This function assumes that `owner` is the actual owner of `tokenId` and does not verify this
* assumption.
*/
function _checkAuthorized(address owner, address spender, uint256 tokenId) internal view virtual {
if (!_isAuthorized(owner, spender, tokenId)) {
if (owner == address(0)) {
revert ERC721NonexistentToken(tokenId);
} else {
revert ERC721InsufficientApproval(spender, tokenId);
}
}
}
/**
* @dev Unsafe write access to the balances, used by extensions that "mint" tokens using an {ownerOf} override.
*
* NOTE: the value is limited to type(uint128).max. This protect against _balance overflow. It is unrealistic that
* a uint256 would ever overflow from increments when these increments are bounded to uint128 values.
*
* WARNING: Increasing an account's balance using this function tends to be paired with an override of the
* {_ownerOf} function to resolve the ownership of the corresponding tokens so that balances and ownership
* remain consistent with one another.
*/
function _increaseBalance(address account, uint128 value) internal virtual {
unchecked {
_balances[account] += value;
}
}
/**
* @dev Transfers `tokenId` from its current owner to `to`, or alternatively mints (or burns) if the current owner
* (or `to`) is the zero address. Returns the owner of the `tokenId` before the update.
*
* The `auth` argument is optional. If the value passed is non 0, then this function will check that
* `auth` is either the owner of the token, or approved to operate on the token (by the owner).
*
* Emits a {Transfer} event.
*
* NOTE: If overriding this function in a way that tracks balances, see also {_increaseBalance}.
*/
function _update(address to, uint256 tokenId, address auth) internal virtual returns (address) {
address from = _ownerOf(tokenId);
// Perform (optional) operator check
if (auth != address(0)) {
_checkAuthorized(from, auth, tokenId);
}
// Execute the update
if (from != address(0)) {
// Clear approval. No need to re-authorize or emit the Approval event
_approve(address(0), tokenId, address(0), false);
unchecked {
_balances[from] -= 1;
}
}
if (to != address(0)) {
unchecked {
_balances[to] += 1;
}
}
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
return from;
}
/**
* @dev Mints `tokenId` and transfers it to `to`.
*
* WARNING: Usage of this method is discouraged, use {_safeMint} whenever possible
*
* Requirements:
*
* - `tokenId` must not exist.
* - `to` cannot be the zero address.
*
* Emits a {Transfer} event.
*/
function _mint(address to, uint256 tokenId) internal {
if (to == address(0)) {
revert ERC721InvalidReceiver(address(0));
}
address previousOwner = _update(to, tokenId, address(0));
if (previousOwner != address(0)) {
revert ERC721InvalidSender(address(0));
}
}
/**
* @dev Mints `tokenId`, transfers it to `to` and checks for `to` acceptance.
*
* Requirements:
*
* - `tokenId` must not exist.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeMint(address to, uint256 tokenId) internal {
_safeMint(to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeMint-address-uint256-}[`_safeMint`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeMint(address to, uint256 tokenId, bytes memory data) internal virtual {
_mint(to, tokenId);
ERC721Utils.checkOnERC721Received(_msgSender(), address(0), to, tokenId, data);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
* This is an internal function that does not check if the sender is authorized to operate on the token.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId) internal {
address previousOwner = _update(address(0), tokenId, address(0));
if (previousOwner == address(0)) {
revert ERC721NonexistentToken(tokenId);
}
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/
function _transfer(address from, address to, uint256 tokenId) internal {
if (to == address(0)) {
revert ERC721InvalidReceiver(address(0));
}
address previousOwner = _update(to, tokenId, address(0));
if (previousOwner == address(0)) {
revert ERC721NonexistentToken(tokenId);
} else if (previousOwner != from) {
revert ERC721IncorrectOwner(from, tokenId, previousOwner);
}
}
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking that contract recipients
* are aware of the ERC-721 standard to prevent tokens from being forever locked.
*
* `data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is like {safeTransferFrom} in the sense that it invokes
* {IERC721Receiver-onERC721Received} on the receiver, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `tokenId` token must exist and be owned by `from`.
* - `to` cannot be the zero address.
* - `from` cannot be the zero address.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
*
* Emits a {Transfer} event.
*/
function _safeTransfer(address from, address to, uint256 tokenId) internal {
_safeTransfer(from, to, tokenId, "");
}
/**
* @dev Same as {xref-ERC721-_safeTransfer-address-address-uint256-}[`_safeTransfer`], with an additional `data` parameter which is
* forwarded in {IERC721Receiver-onERC721Received} to contract recipients.
*/
function _safeTransfer(address from, address to, uint256 tokenId, bytes memory data) internal virtual {
_transfer(from, to, tokenId);
ERC721Utils.checkOnERC721Received(_msgSender(), from, to, tokenId, data);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* The `auth` argument is optional. If the value passed is non 0, then this function will check that `auth` is
* either the owner of the token, or approved to operate on all tokens held by this owner.
*
* Emits an {Approval} event.
*
* Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
*/
function _approve(address to, uint256 tokenId, address auth) internal {
_approve(to, tokenId, auth, true);
}
/**
* @dev Variant of `_approve` with an optional flag to enable or disable the {Approval} event. The event is not
* emitted in the context of transfers.
*/
function _approve(address to, uint256 tokenId, address auth, bool emitEvent) internal virtual {
// Avoid reading the owner unless necessary
if (emitEvent || auth != address(0)) {
address owner = _requireOwned(tokenId);
// We do not use _isAuthorized because single-token approvals should not be able to call approve
if (auth != address(0) && owner != auth && !isApprovedForAll(owner, auth)) {
revert ERC721InvalidApprover(auth);
}
if (emitEvent) {
emit Approval(owner, to, tokenId);
}
}
_tokenApprovals[tokenId] = to;
}
/**
* @dev Approve `operator` to operate on all of `owner` tokens
*
* Requirements:
* - operator can't be the address zero.
*
* Emits an {ApprovalForAll} event.
*/
function _setApprovalForAll(address owner, address operator, bool approved) internal virtual {
if (operator == address(0)) {
revert ERC721InvalidOperator(operator);
}
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @dev Reverts if the `tokenId` doesn't have a current owner (it hasn't been minted, or it has been burned).
* Returns the owner.
*
* Overrides to ownership logic should be done to {_ownerOf}.
*/
function _requireOwned(uint256 tokenId) internal view returns (address) {
address owner = _ownerOf(tokenId);
if (owner == address(0)) {
revert ERC721NonexistentToken(tokenId);
}
return owner;
}
}
"
},
"npm/@openzeppelin/contracts@5.4.0/token/ERC721/extensions/IERC721Metadata.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/extensions/IERC721Metadata.sol)
pragma solidity >=0.6.2;
import {IERC721} from "../IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional metadata extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/
interface IERC721Metadata is IERC721 {
/**
* @dev Returns the token collection name.
*/
function name() external view returns (string memory);
/**
* @dev Returns the token collection symbol.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) external view returns (string memory);
}
"
},
"npm/@openzeppelin/contracts@5.4.0/token/ERC721/IERC721.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/IERC721.sol)
pragma solidity >=0.6.2;
import {IERC165} from "../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC-721 compliant contract.
*/
interface IERC721 is IERC165 {
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/
event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/
event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/
event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/
function balanceOf(address owner) external view returns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) external view returns (address owner);
/**
* @dev Safely transfers `tokenId` token from `from` to `to`.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon
* a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
/**
* @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
* are aware of the ERC-721 protocol to prevent tokens from being forever locked.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - If the caller is not `from`, it must have been allowed to move this token by either {approve} or
* {setApprovalForAll}.
* - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon
* a safe transfer.
*
* Emits a {Transfer} event.
*/
function safeTransferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Transfers `tokenId` token from `from` to `to`.
*
* WARNING: Note that the caller is responsible to confirm that the recipient is capable of receiving ERC-721
* or else they may be permanently lost. Usage of {safeTransferFrom} prevents loss, though the caller must
* understand this adds an external call which potentially creates a reentrancy vulnerability.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
* - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 tokenId) external;
/**
* @dev Gives permission to `to` to transfer `tokenId` token to another account.
* The approval is cleared when the token is transferred.
*
* Only a single account can be approved at a time, so approving the zero address clears previous approvals.
*
* Requirements:
*
* - The caller must own the token or be an approved operator.
* - `tokenId` must exist.
*
* Emits an {Approval} event.
*/
function approve(address to, uint256 tokenId) external;
/**
* @dev Approve or remove `operator` as an operator for the caller.
* Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
*
* Requirements:
*
* - The `operator` cannot be the address zero.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool approved) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) external view returns (address operator);
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/
function isApprovedForAll(address owner, address operator) external view returns (bool);
}
"
},
"npm/@openzeppelin/contracts@5.4.0/token/ERC721/IERC721Receiver.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/IERC721Receiver.sol)
pragma solidity >=0.5.0;
/**
* @title ERC-721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC-721 asset contracts.
*/
interface IERC721Receiver {
/**
* @dev Whenever an {IERC721} `tokenId` token is transferred to this contract via {IERC721-safeTransferFrom}
* by `operator` from `from`, this function is called.
*
* It must return its Solidity selector to confirm the token transfer.
* If any other value is returned or the interface is not implemented by the recipient, the transfer will be
* reverted.
*
* The selector can be obtained in Solidity with `IERC721Receiver.onERC721Received.selector`.
*/
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
"
},
"npm/@openzeppelin/contracts@5.4.0/token/ERC721/utils/ERC721Utils.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/ERC721/utils/ERC721Utils.sol)
pragma solidity ^0.8.20;
import {IERC721Receiver} from "../IERC721Receiver.sol";
import {IERC721Errors} from "../../../interfaces/draft-IERC6093.sol";
/**
* @dev Library that provide common ERC-721 utility functions.
*
* See https://eips.ethereum.org/EIPS/eip-721[ERC-721].
*
* _Available since v5.1._
*/
library ERC721Utils {
/**
* @dev Performs an acceptance check for the provided `operator` by calling {IERC721Receiver-onERC721Received}
* on the `to` address. The `operator` is generally the address that initiated the token transfer (i.e. `msg.sender`).
*
* The acceptance call is not executed and treated as a no-op if the target address doesn't contain code (i.e. an EOA).
* Otherwise, the recipient must implement {IERC721Receiver-onERC721Received} and return the acceptance magic value to accept
* the transfer.
*/
function checkOnERC721Received(
address operator,
address from,
address to,
uint256 tokenId,
bytes memory data
) internal {
if (to.code.length > 0) {
try IERC721Receiver(to).onERC721Received(operator, from, tokenId, data) returns (bytes4 retval) {
if (retval != IERC721Receiver.onERC721Received.selector) {
// Token rejected
revert IERC721Errors.ERC721InvalidReceiver(to);
}
} catch (bytes memory reason) {
if (reason.length == 0) {
// non-IERC721Receiver implementer
revert IERC721Errors.ERC721InvalidReceiver(to);
} else {
assembly ("memory-safe") {
revert(add(reason, 0x20), mload(reason))
}
}
}
}
}
}
"
},
"npm/@openzeppelin/contracts@5.4.0/utils/Context.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)
pragma solidity ^0.8.20;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
"
},
"npm/@openzeppelin/contracts@5.4.0/utils/introspection/ERC165.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (utils/introspection/ERC165.sol)
pragma solidity ^0.8.20;
import {IERC165} from "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC-165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*/
abstract contract ERC165 is IERC165 {
/// @inheritdoc IERC165
function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
"
},
"npm/@openzeppelin/contracts@5.4.0/utils/introspection/IERC165.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (utils/introspection/IERC165.sol)
pragma solidity >=0.4.16;
/**
* @dev Interface of the ERC-165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[ERC].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[ERC section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
"
},
"npm/@openzeppelin/contracts@5.4.0/utils/math/Math.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.3.0) (utils/math/Math.sol)
pragma solidity ^0.8.20;
import {Panic} from "../Panic.sol";
import {SafeCast} from "./SafeCast.sol";
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
enum Rounding {
Floor, // Toward negative infinity
Ceil, // Toward positive infinity
Trunc, // Toward zero
Expand // Away from zero
}
/**
* @dev Return the 512-bit addition of two uint256.
*
* The result is stored in two 256 variables such that sum = high * 2²⁵⁶ + low.
*/
function add512(uint256 a, uint256 b) internal pure returns (uint256 high, uint256 low) {
assembly ("memory-safe") {
low := add(a, b)
high := lt(low, a)
}
}
/**
* @dev Return the 512-bit multiplication of two uint256.
*
* The result is stored in two 256 variables such that product = high * 2²⁵⁶ + low.
*/
function mul512(uint256 a, uint256 b) internal pure returns (uint256 high, uint256 low) {
// 512-bit multiply [high low] = x * y. Compute the product mod 2²⁵⁶ and mod 2²⁵⁶ - 1, then use
// the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
// variables such that product = high * 2²⁵⁶ + low.
assembly ("memory-safe") {
let mm := mulmod(a, b, not(0))
low := mul(a, b)
high := sub(sub(mm, low), lt(mm, low))
}
}
/**
* @dev Returns the addition of two unsigned integers, with a success flag (no overflow).
*/
function tryAdd(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
unchecked {
uint256 c = a + b;
success = c >= a;
result = c * SafeCast.toUint(success);
}
}
/**
* @dev Returns the subtraction of two unsigned integers, with a success flag (no overflow).
*/
function trySub(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
unchecked {
uint256 c = a - b;
success = c <= a;
result = c * SafeCast.toUint(success);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with a success flag (no overflow).
*/
function tryMul(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
unchecked {
uint256 c = a * b;
assembly ("memory-safe") {
// Only true when the multiplication doesn't overflow
// (c / a == b) || (a == 0)
success := or(eq(div(c, a), b), iszero(a))
}
// equivalent to: success ? c : 0
result = c * SafeCast.toUint(success);
}
}
/**
* @dev Returns the division of two unsigned integers, with a success flag (no division by zero).
*/
function tryDiv(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
unchecked {
success = b > 0;
assembly ("memory-safe") {
// The `DIV` opcode returns zero when the denominator is 0.
result := div(a, b)
}
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a success flag (no division by zero).
*/
function tryMod(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
unchecked {
success = b > 0;
assembly ("memory-safe") {
// The `MOD` opcode returns zero when the denominator is 0.
result := mod(a, b)
}
}
}
/**
* @dev Unsigned saturating addition, bounds to `2²⁵⁶ - 1` instead of overflowing.
*/
function saturatingAdd(uint256 a, uint256 b) internal pure returns (uint256) {
(bool success, uint256 result) = tryAdd(a, b);
return ternary(success, result, type(uint256).max);
}
/**
* @dev Unsigned saturating subtraction, bounds to zero instead of overflowing.
*/
function saturatingSub(uint256 a, uint256 b) internal pure returns (uint256) {
(, uint256 result) = trySub(a, b);
return result;
}
/**
* @dev Unsigned saturating multiplication, bounds to `2²⁵⁶ - 1` instead of overflowing.
*/
function saturatingMul(uint256 a, uint256 b) internal pure returns (uint256) {
(bool success, uint256 result) = tryMul(a, b);
return ternary(success, result, type(uint256).max);
}
/**
* @dev Branchless ternary evaluation for `a ? b : c`. Gas costs are constant.
*
* IMPORTANT: This function may reduce bytecode size and consume less gas when used standalone.
* However, the compiler may optimize Solidity ternary operations (i.e. `a ? b : c`) to only compute
* one branch when needed, making this function more expensive.
*/
function ternary(bool condition, uint256 a, uint256 b) internal pure returns (uint256) {
unchecked {
// branchless ternary works because:
// b ^ (a ^ b) == a
// b ^ 0 == b
return b ^ ((a ^ b) * SafeCast.toUint(condition));
}
}
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return ternary(a > b, a, b);
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return ternary(a < b, a, b);
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b) / 2 can overflow.
return (a & b) + (a ^ b) / 2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds towards infinity instead
* of rounding towards zero.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
if (b == 0) {
// Guarantee the same behavior as in a regular Solidity division.
Panic.panic(Panic.DIVISION_BY_ZERO);
}
// The following calculation ensures accurate ceiling division without overflow.
// Since a is non-zero, (a - 1) / b will not overflow.
// The largest possible result occurs when (a - 1) / b is type(uint256).max,
// but the largest value we can obtain is type(uint256).max - 1, which happens
// when a = type(uint256).max and b = 1.
unchecked {
return SafeCast.toUint(a > 0) * ((a - 1) / b + 1);
}
}
/**
* @dev Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or
* denominator == 0.
*
* Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv) with further edits by
* Uniswap Labs also under MIT license.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
unchecked {
(uint256 high, uint256 low) = mul512(x, y);
// Handle non-overflow cases, 256 by 256 division.
if (high == 0) {
// Solidity will revert if denominator == 0, unlike the div opcode on its own.
// The surrounding unchecked block does not change this fact.
// See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
return low / denominator;
}
// Make sure the result is less than 2²⁵⁶. Also prevents denominator == 0.
if (denominator <= high) {
Panic.panic(ternary(denominator == 0, Panic.DIVISION_BY_ZERO, Panic.UNDER_OVERFLOW));
}
///////////////////////////////////////////////
// 512 by 256 division.
///////////////////////////////////////////////
// Make division exact by subtracting the remainder from [high low].
uint256 remainder;
assembly ("memory-safe") {
// Compute remainder using mulmod.
remainder := mulmod(x, y, denominator)
// Subtract 256 bit number from 512 bit number.
high := sub(high, gt(remainder, low))
low := sub(low, remainder)
}
// Factor powers of two out of denominator and compute largest power of two divisor of denominator.
// Always >= 1. See https://cs.stackexchange.com/q/138556/92363.
uint256 twos = denominator & (0 - denominator);
assembly ("memory-safe") {
// Divide denominator by twos.
denominator := div(denominator, twos)
// Divide [high low] by twos.
low := div(low, twos)
// Flip twos such that it is 2²⁵⁶ / twos. If twos is zero, then it becomes one.
twos := add(div(sub(0, twos), twos), 1)
}
// Shift in bits from high into low.
low |= high * twos;
// Invert denominator mod 2²⁵⁶. Now that denominator is an odd number, it has an inverse modulo 2²⁵⁶ such
// that denominator * inv ≡ 1 mod 2²⁵⁶. Compute the inverse by starting with a seed that is correct for
// four bits. That is, denominator * inv ≡ 1 mod 2⁴.
uint256 inverse = (3 * denominator) ^ 2;
// Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also
// works in modular arithmetic, doubling the correct bits in each step.
inverse *= 2 - denominator * inverse; // inverse mod 2⁸
inverse *= 2 - denominator * inverse; // inverse mod 2¹⁶
inverse *= 2 - denominator * inverse; // inverse mod 2³²
inverse *= 2 - denominator * inverse; // inverse mod 2⁶⁴
inverse *= 2 - denominator * inverse; // inverse mod 2¹²⁸
inverse *= 2 - denominator * inverse; // inverse mod 2²⁵⁶
// Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
// This will give us the correct result modulo 2²⁵⁶. Since the preconditions guarantee that the outcome is
// less than 2²⁵⁶, this is the final result. We don't need to compute the high bits of the result and high
// is no longer required.
result = low * inverse;
return result;
}
}
/**
* @dev Calculates x * y / denominator with full precision, following the selected rounding direction.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
return mulDiv(x, y, denominator) + SafeCast.toUint(unsignedRoundsUp(rounding) && mulmod(x, y, denominator) > 0);
}
/**
* @dev Calculates floor(x * y >> n) with full precision. Throws if result overflows a uint256.
*/
function mulShr(uint256 x, uint256 y, uint8 n) internal pure returns (uint256 result) {
unchecked {
(uint256 high, uint256 low) = mul512(x, y);
if (high >= 1 << n) {
Panic.panic(Panic.UNDER_OVERFLOW);
}
return (high << (256 - n)) | (low >> n);
}
}
/**
* @dev Calculates x * y >> n with full precision, following the selected rounding direction.
*/
function mulShr(uint256 x, uint256 y, uint8 n, Rounding rounding) internal pure returns (uint256) {
return mulShr(x, y, n) + SafeCast.toUint(unsignedRoundsUp(rounding) && mulmod(x, y, 1 << n) > 0);
}
/**
* @dev Calculate the modular multiplicative inverse of a number in Z/nZ.
*
* If n is a prime, then Z/nZ is a field. In that case all elements are inversible, except 0.
* If n is not a prime, then Z/nZ is not a field, and some elements might not be inversible.
*
* If the input value is not inversible, 0 is returned.
*
* NOTE: If you know for sure that n is (big) a prime, it may be cheaper to use Fermat's little theorem and get the
* inverse using `Math.modExp(a, n - 2, n)`. See {invModPrime}.
*/
function invMod(uint256 a, uint256 n) internal pure returns (uint256) {
unchecked {
if (n == 0) return 0;
// The inverse modulo is calculated using the Extended Euclidean Algorithm (iterative version)
// Used to compute integers x and y such that: ax + ny = gcd(a, n).
// When the gcd is 1, then the inverse of a modulo n exists and it's x.
// ax + ny = 1
// ax = 1 + (-y)n
// ax ≡ 1 (mod n) # x is the inverse of a modulo n
// If the remainder is 0 the gcd is n right away.
uint256 remainder = a % n;
uint256 gcd = n;
// Therefore the initial coefficients are:
// ax + ny = gcd(a, n) = n
// 0a + 1n = n
int256 x = 0;
int256 y = 1;
while (remainder != 0) {
uint256 quotient = gcd / remainder;
(gcd, remainder) = (
// The old remainder is the next gcd to try.
remainder,
// Compute the next remainder.
// Can't overflow given that (a % gcd) * (gcd // (a % gcd)) <= gcd
// where gcd is at most n (capped to type(uint256).max)
gcd - remainder * quotient
);
(x, y) = (
// Increment the coefficient of a.
y,
// Decrement the coefficient of n.
// Can overflow, but the result is casted to uint256 so that the
// next value of y is "wrapped around" to a value between 0 and n - 1.
x - y * int256(quotient)
);
}
if (gcd != 1) return 0; // No inverse exists.
return ternary(x < 0, n - uint256(-x), uint256(x)); // Wrap the result if it's negative.
}
}
/**
* @dev Variant of {invMod}. More efficient, but only works if `p` is known to be a prime greater than `2`.
*
* From https://en.wikipedia.org/wiki/Fermat%27s_little_theorem[Fermat's little theorem], we know that if p is
* prime, then `a**(p-1) ≡ 1 mod p`. As a consequence, we have `a * a**(p-2) ≡ 1 mod p`, which means that
* `a**(p-2)` is the modular multiplicative inverse of a in Fp.
*
* NOTE: this function does NOT check that `p` is a prime greater than `2`.
*/
function invModPrime(uint256 a, uint256 p) internal view returns (uint256) {
unchecked {
return Math.modExp(a, p - 2, p);
}
}
/**
* @dev Returns the modular exponentiation of the specified base, exponent and modulus (b ** e % m)
*
* Requirements:
* - modulus can't be zero
* - underlying staticcall to precompile must succeed
*
* IMPORTANT: The result is only valid if the undeSubmitted on: 2025-09-17 12:33:04
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