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",
"sources": {
"@openzeppelin/contracts/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);
}
}
"
},
"@openzeppelin/contracts/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);
}
"
},
"@openzeppelin/contracts/interfaces/IERC2981.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (interfaces/IERC2981.sol)
pragma solidity >=0.6.2;
import {IERC165} from "../utils/introspection/IERC165.sol";
/**
* @dev Interface for the NFT Royalty Standard.
*
* A standardized way to retrieve royalty payment information for non-fungible tokens (NFTs) to enable universal
* support for royalty payments across all NFT marketplaces and ecosystem participants.
*/
interface IERC2981 is IERC165 {
/**
* @dev Returns how much royalty is owed and to whom, based on a sale price that may be denominated in any unit of
* exchange. The royalty amount is denominated and should be paid in that same unit of exchange.
*
* NOTE: ERC-2981 allows setting the royalty to 100% of the price. In that case all the price would be sent to the
* royalty receiver and 0 tokens to the seller. Contracts dealing with royalty should consider empty transfers.
*/
function royaltyInfo(
uint256 tokenId,
uint256 salePrice
) external view returns (address receiver, uint256 royaltyAmount);
}
"
},
"@openzeppelin/contracts/token/common/ERC2981.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (token/common/ERC2981.sol)
pragma solidity ^0.8.20;
import {IERC2981} from "../../interfaces/IERC2981.sol";
import {IERC165, ERC165} from "../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of the NFT Royalty Standard, a standardized way to retrieve royalty payment information.
*
* Royalty information can be specified globally for all token ids via {_setDefaultRoyalty}, and/or individually for
* specific token ids via {_setTokenRoyalty}. The latter takes precedence over the first.
*
* Royalty is specified as a fraction of sale price. {_feeDenominator} is overridable but defaults to 10000, meaning the
* fee is specified in basis points by default.
*
* IMPORTANT: ERC-2981 only specifies a way to signal royalty information and does not enforce its payment. See
* https://eips.ethereum.org/EIPS/eip-2981#optional-royalty-payments[Rationale] in the ERC. Marketplaces are expected to
* voluntarily pay royalties together with sales, but note that this standard is not yet widely supported.
*/
abstract contract ERC2981 is IERC2981, ERC165 {
struct RoyaltyInfo {
address receiver;
uint96 royaltyFraction;
}
RoyaltyInfo private _defaultRoyaltyInfo;
mapping(uint256 tokenId => RoyaltyInfo) private _tokenRoyaltyInfo;
/**
* @dev The default royalty set is invalid (eg. (numerator / denominator) >= 1).
*/
error ERC2981InvalidDefaultRoyalty(uint256 numerator, uint256 denominator);
/**
* @dev The default royalty receiver is invalid.
*/
error ERC2981InvalidDefaultRoyaltyReceiver(address receiver);
/**
* @dev The royalty set for a specific `tokenId` is invalid (eg. (numerator / denominator) >= 1).
*/
error ERC2981InvalidTokenRoyalty(uint256 tokenId, uint256 numerator, uint256 denominator);
/**
* @dev The royalty receiver for `tokenId` is invalid.
*/
error ERC2981InvalidTokenRoyaltyReceiver(uint256 tokenId, address receiver);
/// @inheritdoc IERC165
function supportsInterface(bytes4 interfaceId) public view virtual override(IERC165, ERC165) returns (bool) {
return interfaceId == type(IERC2981).interfaceId || super.supportsInterface(interfaceId);
}
/// @inheritdoc IERC2981
function royaltyInfo(
uint256 tokenId,
uint256 salePrice
) public view virtual returns (address receiver, uint256 amount) {
RoyaltyInfo storage _royaltyInfo = _tokenRoyaltyInfo[tokenId];
address royaltyReceiver = _royaltyInfo.receiver;
uint96 royaltyFraction = _royaltyInfo.royaltyFraction;
if (royaltyReceiver == address(0)) {
royaltyReceiver = _defaultRoyaltyInfo.receiver;
royaltyFraction = _defaultRoyaltyInfo.royaltyFraction;
}
uint256 royaltyAmount = (salePrice * royaltyFraction) / _feeDenominator();
return (royaltyReceiver, royaltyAmount);
}
/**
* @dev The denominator with which to interpret the fee set in {_setTokenRoyalty} and {_setDefaultRoyalty} as a
* fraction of the sale price. Defaults to 10000 so fees are expressed in basis points, but may be customized by an
* override.
*/
function _feeDenominator() internal pure virtual returns (uint96) {
return 10000;
}
/**
* @dev Sets the royalty information that all ids in this contract will default to.
*
* Requirements:
*
* - `receiver` cannot be the zero address.
* - `feeNumerator` cannot be greater than the fee denominator.
*/
function _setDefaultRoyalty(address receiver, uint96 feeNumerator) internal virtual {
uint256 denominator = _feeDenominator();
if (feeNumerator > denominator) {
// Royalty fee will exceed the sale price
revert ERC2981InvalidDefaultRoyalty(feeNumerator, denominator);
}
if (receiver == address(0)) {
revert ERC2981InvalidDefaultRoyaltyReceiver(address(0));
}
_defaultRoyaltyInfo = RoyaltyInfo(receiver, feeNumerator);
}
/**
* @dev Removes default royalty information.
*/
function _deleteDefaultRoyalty() internal virtual {
delete _defaultRoyaltyInfo;
}
/**
* @dev Sets the royalty information for a specific token id, overriding the global default.
*
* Requirements:
*
* - `receiver` cannot be the zero address.
* - `feeNumerator` cannot be greater than the fee denominator.
*/
function _setTokenRoyalty(uint256 tokenId, address receiver, uint96 feeNumerator) internal virtual {
uint256 denominator = _feeDenominator();
if (feeNumerator > denominator) {
// Royalty fee will exceed the sale price
revert ERC2981InvalidTokenRoyalty(tokenId, feeNumerator, denominator);
}
if (receiver == address(0)) {
revert ERC2981InvalidTokenRoyaltyReceiver(tokenId, address(0));
}
_tokenRoyaltyInfo[tokenId] = RoyaltyInfo(receiver, feeNumerator);
}
/**
* @dev Resets royalty information for the token id back to the global default.
*/
function _resetTokenRoyalty(uint256 tokenId) internal virtual {
delete _tokenRoyaltyInfo[tokenId];
}
}
"
},
"@openzeppelin/contracts/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;
}
}
"
},
"@openzeppelin/contracts/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);
}
"
},
"@openzeppelin/contracts/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);
}
"
},
"@openzeppelin/contracts/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);
}
"
},
"@openzeppelin/contracts/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))
}
}
}
}
}
}
"
},
"@openzeppelin/contracts/utils/Base64.sol": {
"content": "// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.4.0) (utils/Base64.sol)
pragma solidity ^0.8.20;
/**
* @dev Provides a set of functions to operate with Base64 strings.
*/
library Base64 {
/**
* @dev Base64 Encoding/Decoding Table
* See sections 4 and 5 of https://datatracker.ietf.org/doc/html/rfc4648
*/
string internal constant _TABLE = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
string internal constant _TABLE_URL = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
/**
* @dev Converts a `bytes` to its Bytes64 `string` representation.
*/
function encode(bytes memory data) internal pure returns (string memory) {
return _encode(data, _TABLE, true);
}
/**
* @dev Converts a `bytes` to its Bytes64Url `string` representation.
* Output is not padded with `=` as specified in https://www.rfc-editor.org/rfc/rfc4648[rfc4648].
*/
function encodeURL(bytes memory data) internal pure returns (string memory) {
return _encode(data, _TABLE_URL, false);
}
/**
* @dev Internal table-agnostic conversion
*/
function _encode(bytes memory data, string memory table, bool withPadding) private pure returns (string memory) {
/**
* Inspired by Brecht Devos (Brechtpd) implementation - MIT licence
* https://github.com/Brechtpd/base64/blob/e78d9fd951e7b0977ddca77d92dc85183770daf4/base64.sol
*/
if (data.length == 0) return "";
// If padding is enabled, the final length should be `bytes` data length divided by 3 rounded up and then
// multiplied by 4 so that it leaves room for padding the last chunk
// - `data.length + 2` -> Prepare for division rounding up
// - `/ 3` -> Number of 3-bytes chunks (rounded up)
// - `4 *` -> 4 characters for each chunk
// This is equivalent to: 4 * Math.ceil(data.length / 3)
//
// If padding is disabled, the final length should be `bytes` data length multiplied by 4/3 rounded up as
// opposed to when padding is required to fill the last chunk.
// - `4 * data.length` -> 4 characters for each chunk
// - ` + 2` -> Prepare for division rounding up
// - `/ 3` -> Number of 3-bytes chunks (rounded up)
// This is equivalent to: Math.ceil((4 * data.length) / 3)
uint256 resultLength = withPadding ? 4 * ((data.length + 2) / 3) : (4 * data.length + 2) / 3;
string memory result = new string(resultLength);
assembly ("memory-safe") {
// Prepare the lookup table (skip the first "length" byte)
let tablePtr := add(table, 1)
// Prepare result pointer, jump over length
let resultPtr := add(result, 0x20)
let dataPtr := data
let endPtr := add(data, mload(data))
// In some cases, the last iteration will read bytes after the end of the data. We cache the value, and
// set it to zero to make sure no dirty bytes are read in that section.
let afterPtr := add(endPtr, 0x20)
let afterCache := mload(afterPtr)
mstore(afterPtr, 0x00)
// Run over the input, 3 bytes at a time
for {} lt(dataPtr, endPtr) {} {
// Advance 3 bytes
dataPtr := add(dataPtr, 3)
let input := mload(dataPtr)
// To write each character, shift the 3 byte (24 bits) chunk
// 4 times in blocks of 6 bits for each character (18, 12, 6, 0)
// and apply logical AND with 0x3F to bitmask the least significant 6 bits.
// Use this as an index into the lookup table, mload an entire word
// so the desired character is in the least significant byte, and
// mstore8 this least significant byte into the result and continue.
mstore8(resultPtr, mload(add(tablePtr, and(shr(18, input), 0x3F))))
resultPtr := add(resultPtr, 1) // Advance
mstore8(resultPtr, mload(add(tablePtr, and(shr(12, input), 0x3F))))
resultPtr := add(resultPtr, 1) // Advance
mstore8(resultPtr, mload(add(tablePtr, and(shr(6, input), 0x3F))))
resultPtr := add(resultPtr, 1) // Advance
mstore8(resultPtr, mload(add(tablePtr, and(input, 0x3F))))
resultPtr := add(resultPtr, 1) // Advance
}
// Reset the value that was cached
mstore(afterPtr, afterCache)
if withPadding {
// When data `bytes` is not exactly 3 bytes long
// it is padded with `=` characters at the end
switch mod(mload(data), 3)
case 1 {
mstore8(sub(resultPtr, 1), 0x3d)
mstore8(sub(resultPtr, 2), 0x3d)
}
case 2 {
mstore8(sub(resultPtr, 1), 0x3d)
}
}
}
return result;
}
}
"
},
"@openzeppelin/contracts/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;
}
}
"
},
"@openzeppelin/contracts/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;
}
}
"
},
"@openzeppelin/contracts/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);
}
"
},
"@openzeppelin/contracts/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 %
Submitted on: 2025-11-04 12:15:47
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