Contract Source Code:
//SPDX-License-Identifier: MIT
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pragma solidity ^0.8.15;
import "./ERC721ABase.sol";
import "openzeppelin-contracts/contracts/security/ReentrancyGuard.sol";
import { MerkleProof } from "openzeppelin-contracts/contracts/utils/cryptography/MerkleProof.sol";
contract Ghouls is ERC721ABase, ReentrancyGuard {
// =========================================================================
// Types
// =========================================================================
/**
* @notice Struct encoding an airdrop: Receiver + number of passes.
*/
struct Airdrop {
address to;
uint64 num;
}
/**
* @notice Sales states and configuration.
*/
struct SalesConfiguration {
uint104 publicSalePrice;
uint64 publicSaleStart;
uint64 allowlistStart;
bytes32 allowlistMerkleRoot;
}
/**
* @notice Return value for sale details
*/
struct SaleDetails {
bool publicSaleActive;
bool allowlistActive;
uint256 publicSalePrice;
uint64 publicSaleStart;
uint64 allowlistStart;
bytes32 allowlistMerkleRoot;
uint256 totalMinted;
uint256 maxSupply;
}
// /**
// * @notice Return type of specific mint counts and details per address
// */
// struct AddressMintDetails {
// /// Number of total mints from the given address
// uint256 totalMints;
// /// Number of presale mints from the given address
// uint256 presaleMints;
// /// Number of public mints from the given address
// uint256 publicMints;
// }
// =========================================================================
// Events
// =========================================================================
event BatchAirdropped(uint256 total);
event Sale(
address indexed to,
uint256 indexed quantity,
uint256 indexed pricePerToken,
uint256 firstPurchasedTokenId
);
event SalesConfigChanged(address indexed changedBy);
event Withdrawn(uint256 amount);
// =========================================================================
// Errors
// =========================================================================
error AirdropExceedsMaxSupply();
error AirdropTotalMismatch();
error Mint_SoldOut();
error AllowList_MerkleNotApproved();
error Purchase_WrongPrice(uint256 correctPrice);
error AllowList_TooManyForAddress();
error Sale_NotStarted();
// =========================================================================
// Constants
// =========================================================================
uint256 public constant NUM_MAX_GHOULS = 666;
uint256 public constant NUM_AIRDROP_FREE = 109;
// =========================================================================
// Storage
// =========================================================================
SalesConfiguration public salesConfig;
mapping(address => uint256) internal allowlistMintsByAddress;
address payable private _DBSTreasury;
// =========================================================================
// Modifiers
// =========================================================================
/// @notice Allows user to mint tokens at a quantity
modifier canMintTokens(uint256 quantity) {
if (quantity + _totalMinted() > NUM_MAX_GHOULS - NUM_AIRDROP_FREE) {
revert Mint_SoldOut();
}
_;
}
function _publicSaleActive() internal view returns (bool) {
return block.timestamp >= salesConfig.publicSaleStart;
}
/* @notice Returns status of public sale */
modifier publicSaleActive() {
if (!_publicSaleActive()) {
revert Sale_NotStarted();
}
_;
}
function _allowlistActive() internal view returns (bool) {
return block.timestamp >= salesConfig.allowlistStart;
}
/* @notice Returns status of allowlist */
modifier allowlistActive() {
if (!_allowlistActive()) {
revert Sale_NotStarted();
}
_;
}
// =========================================================================
// Constructor
// =========================================================================
constructor(
string memory name,
string memory symbol,
string memory baseTokenURI_,
address payable dbsTreasury,
address payable royaltyReceiver,
uint96 royaltyBPS,
SalesConfiguration memory salesConfig_
) ERC721ABase(name, symbol, baseTokenURI_, royaltyReceiver, royaltyBPS) {
// Update salesConfig
salesConfig = salesConfig_;
// Set DBS Treasury
_DBSTreasury = dbsTreasury;
}
// =========================================================================
// Minting
// =========================================================================
/* @notice Airdrop tokens to DBS treasury and admins */
function airdrop(Airdrop[] calldata airdrops, uint256 expectedTotal)
external
onlyOwner
{
uint256 total;
for (uint256 idx = 0; idx < airdrops.length; ++idx) {
_mint(airdrops[idx].to, airdrops[idx].num);
total += airdrops[idx].num;
}
if (_totalMinted() > NUM_MAX_GHOULS) revert AirdropExceedsMaxSupply();
if (total != expectedTotal) revert AirdropTotalMismatch();
emit BatchAirdropped(total);
}
/* @notice Merkle-tree presale function. */
function purchaseAllowList(
uint256 quantity,
uint256 maxQuantity,
uint256 pricePerToken,
bytes32[] calldata merkleProof
)
external
payable
nonReentrant
canMintTokens(quantity)
allowlistActive
returns (uint256)
{
if (
!MerkleProof.verify(
merkleProof,
salesConfig.allowlistMerkleRoot,
keccak256(abi.encode(_msgSender(), maxQuantity, pricePerToken))
)
) {
revert AllowList_MerkleNotApproved();
}
if (msg.value != pricePerToken * quantity) {
revert Purchase_WrongPrice(pricePerToken * quantity);
}
allowlistMintsByAddress[_msgSender()] += quantity;
if (allowlistMintsByAddress[_msgSender()] > maxQuantity) {
revert AllowList_TooManyForAddress();
}
uint256 firstMintedTokenId = _nextTokenId();
_mint(_msgSender(), quantity);
emit Sale({
to: _msgSender(),
quantity: quantity,
pricePerToken: pricePerToken,
firstPurchasedTokenId: firstMintedTokenId
});
return firstMintedTokenId;
}
/* @notice Public sale function. */
function purchase(uint256 quantity)
external
payable
nonReentrant
canMintTokens(quantity)
publicSaleActive
returns (uint256)
{
uint256 salePrice = salesConfig.publicSalePrice;
if (msg.value != salePrice * quantity) {
revert Purchase_WrongPrice(salePrice * quantity);
}
uint256 firstMintedTokenId = _nextTokenId();
_mint(_msgSender(), quantity);
emit Sale({
to: _msgSender(),
quantity: quantity,
pricePerToken: salePrice,
firstPurchasedTokenId: firstMintedTokenId
});
return firstMintedTokenId;
}
// =========================================================================
// WITHDRAWAL
// =========================================================================
/* @notice Withdraws funds from contract to DBS Treasury. */
function withdraw() external onlyOwner {
uint256 balance = address(this).balance;
require(balance > 0, "Nothing to withdraw");
_DBSTreasury.transfer(balance);
emit Withdrawn(balance);
}
// =========================================================================
// GETTERS
// =========================================================================
/* @notice Returns full details of the sale to be used by the frontend. */
function getSaleDetails() external view returns (SaleDetails memory) {
return
SaleDetails({
publicSaleActive: _publicSaleActive(),
allowlistActive: _allowlistActive(),
publicSalePrice: salesConfig.publicSalePrice,
publicSaleStart: salesConfig.publicSaleStart,
allowlistStart: salesConfig.allowlistStart,
allowlistMerkleRoot: salesConfig.allowlistMerkleRoot,
totalMinted: _totalMinted(),
maxSupply: NUM_MAX_GHOULS
});
}
function getDBSTreasury() external view returns (address) {
return _DBSTreasury;
}
// =========================================================================
// SETTERS
// =========================================================================
/* @notice Sets the sale configuration. */
function setSaleConfiguration(SalesConfiguration memory _salesConfig)
external
onlyOwner
{
salesConfig = _salesConfig;
emit SalesConfigChanged(_msgSender());
}
function setDBSTreasury(address payable dbsTreasury) external onlyOwner {
_DBSTreasury = dbsTreasury;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.15;
import "ERC721A/ERC721A.sol";
import "openzeppelin-contracts/contracts/access/Ownable.sol";
import "openzeppelin-contracts/contracts/security/Pausable.sol";
import "openzeppelin-contracts/contracts/token/common/ERC2981.sol";
contract ERC721ABase is ERC721A, Ownable, Pausable, ERC2981 {
string private baseURI;
constructor(
string memory name,
string memory symbol,
string memory baseURI_,
address payable royaltyRecipient,
uint96 royaltyBPS
) ERC721A(name, symbol) {
_setDefaultRoyalty(royaltyRecipient, royaltyBPS);
baseURI = baseURI_;
}
modifier tokenExists(uint256 tokenId) {
require(ERC721A._exists(tokenId), "ERC721ABase: token does not exist");
_;
}
modifier onlyApprovedOrOwner(uint256 tokenId) {
require(
_ownershipOf(tokenId).addr == _msgSender() ||
getApproved(tokenId) == _msgSender(),
"ERC721ABase: caller is not owner nor approved"
);
_;
}
function setBaseURI(string memory baseURI_) external onlyOwner {
baseURI = baseURI_;
}
function _beforeTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual override {
require(!paused(), "ERC721ABase: token transfer while paused");
super._beforeTokenTransfers(from, to, startTokenId, quantity);
}
// @notice: Overrides _startTokenId in ERC721A
function _startTokenId() internal pure virtual override returns (uint256) {
return 1;
}
// @notice Overrides _baseURI() in ERC721A
function _baseURI() internal view virtual override returns (string memory) {
return baseURI;
}
// @notice Overrides supportsInterface as required by inheritance.
function supportsInterface(bytes4 interfaceId)
public
view
virtual
override(ERC721A, ERC2981)
returns (bool)
{
return
ERC721A.supportsInterface(interfaceId) ||
ERC2981.supportsInterface(interfaceId);
}
function setDefaultRoyalty(address receiver, uint96 basisPoints)
public
virtual
onlyOwner
{
_setDefaultRoyalty(receiver, basisPoints);
}
/// @notice Pauses the contract.
function pause() public onlyOwner {
Pausable._pause();
}
/// @notice Unpauses the contract.
function unpause() public onlyOwner {
Pausable._unpause();
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
constructor() {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/cryptography/MerkleProof.sol)
pragma solidity ^0.8.0;
/**
* @dev These functions deal with verification of Merkle Tree proofs.
*
* The proofs can be generated using the JavaScript library
* https://github.com/miguelmota/merkletreejs[merkletreejs].
* Note: the hashing algorithm should be keccak256 and pair sorting should be enabled.
*
* See `test/utils/cryptography/MerkleProof.test.js` for some examples.
*
* WARNING: You should avoid using leaf values that are 64 bytes long prior to
* hashing, or use a hash function other than keccak256 for hashing leaves.
* This is because the concatenation of a sorted pair of internal nodes in
* the merkle tree could be reinterpreted as a leaf value.
*/
library MerkleProof {
/**
* @dev Returns true if a `leaf` can be proved to be a part of a Merkle tree
* defined by `root`. For this, a `proof` must be provided, containing
* sibling hashes on the branch from the leaf to the root of the tree. Each
* pair of leaves and each pair of pre-images are assumed to be sorted.
*/
function verify(
bytes32[] memory proof,
bytes32 root,
bytes32 leaf
) internal pure returns (bool) {
return processProof(proof, leaf) == root;
}
/**
* @dev Calldata version of {verify}
*
* _Available since v4.7._
*/
function verifyCalldata(
bytes32[] calldata proof,
bytes32 root,
bytes32 leaf
) internal pure returns (bool) {
return processProofCalldata(proof, leaf) == root;
}
/**
* @dev Returns the rebuilt hash obtained by traversing a Merkle tree up
* from `leaf` using `proof`. A `proof` is valid if and only if the rebuilt
* hash matches the root of the tree. When processing the proof, the pairs
* of leafs & pre-images are assumed to be sorted.
*
* _Available since v4.4._
*/
function processProof(bytes32[] memory proof, bytes32 leaf) internal pure returns (bytes32) {
bytes32 computedHash = leaf;
for (uint256 i = 0; i < proof.length; i++) {
computedHash = _hashPair(computedHash, proof[i]);
}
return computedHash;
}
/**
* @dev Calldata version of {processProof}
*
* _Available since v4.7._
*/
function processProofCalldata(bytes32[] calldata proof, bytes32 leaf) internal pure returns (bytes32) {
bytes32 computedHash = leaf;
for (uint256 i = 0; i < proof.length; i++) {
computedHash = _hashPair(computedHash, proof[i]);
}
return computedHash;
}
/**
* @dev Returns true if the `leaves` can be proved to be a part of a Merkle tree defined by
* `root`, according to `proof` and `proofFlags` as described in {processMultiProof}.
*
* _Available since v4.7._
*/
function multiProofVerify(
bytes32[] memory proof,
bool[] memory proofFlags,
bytes32 root,
bytes32[] memory leaves
) internal pure returns (bool) {
return processMultiProof(proof, proofFlags, leaves) == root;
}
/**
* @dev Calldata version of {multiProofVerify}
*
* _Available since v4.7._
*/
function multiProofVerifyCalldata(
bytes32[] calldata proof,
bool[] calldata proofFlags,
bytes32 root,
bytes32[] memory leaves
) internal pure returns (bool) {
return processMultiProofCalldata(proof, proofFlags, leaves) == root;
}
/**
* @dev Returns the root of a tree reconstructed from `leaves` and the sibling nodes in `proof`,
* consuming from one or the other at each step according to the instructions given by
* `proofFlags`.
*
* _Available since v4.7._
*/
function processMultiProof(
bytes32[] memory proof,
bool[] memory proofFlags,
bytes32[] memory leaves
) internal pure returns (bytes32 merkleRoot) {
// This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by
// consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the
// `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of
// the merkle tree.
uint256 leavesLen = leaves.length;
uint256 totalHashes = proofFlags.length;
// Check proof validity.
require(leavesLen + proof.length - 1 == totalHashes, "MerkleProof: invalid multiproof");
// The xxxPos values are "pointers" to the next value to consume in each array. All accesses are done using
// `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's "pop".
bytes32[] memory hashes = new bytes32[](totalHashes);
uint256 leafPos = 0;
uint256 hashPos = 0;
uint256 proofPos = 0;
// At each step, we compute the next hash using two values:
// - a value from the "main queue". If not all leaves have been consumed, we get the next leaf, otherwise we
// get the next hash.
// - depending on the flag, either another value for the "main queue" (merging branches) or an element from the
// `proof` array.
for (uint256 i = 0; i < totalHashes; i++) {
bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];
bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];
hashes[i] = _hashPair(a, b);
}
if (totalHashes > 0) {
return hashes[totalHashes - 1];
} else if (leavesLen > 0) {
return leaves[0];
} else {
return proof[0];
}
}
/**
* @dev Calldata version of {processMultiProof}
*
* _Available since v4.7._
*/
function processMultiProofCalldata(
bytes32[] calldata proof,
bool[] calldata proofFlags,
bytes32[] memory leaves
) internal pure returns (bytes32 merkleRoot) {
// This function rebuild the root hash by traversing the tree up from the leaves. The root is rebuilt by
// consuming and producing values on a queue. The queue starts with the `leaves` array, then goes onto the
// `hashes` array. At the end of the process, the last hash in the `hashes` array should contain the root of
// the merkle tree.
uint256 leavesLen = leaves.length;
uint256 totalHashes = proofFlags.length;
// Check proof validity.
require(leavesLen + proof.length - 1 == totalHashes, "MerkleProof: invalid multiproof");
// The xxxPos values are "pointers" to the next value to consume in each array. All accesses are done using
// `xxx[xxxPos++]`, which return the current value and increment the pointer, thus mimicking a queue's "pop".
bytes32[] memory hashes = new bytes32[](totalHashes);
uint256 leafPos = 0;
uint256 hashPos = 0;
uint256 proofPos = 0;
// At each step, we compute the next hash using two values:
// - a value from the "main queue". If not all leaves have been consumed, we get the next leaf, otherwise we
// get the next hash.
// - depending on the flag, either another value for the "main queue" (merging branches) or an element from the
// `proof` array.
for (uint256 i = 0; i < totalHashes; i++) {
bytes32 a = leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++];
bytes32 b = proofFlags[i] ? leafPos < leavesLen ? leaves[leafPos++] : hashes[hashPos++] : proof[proofPos++];
hashes[i] = _hashPair(a, b);
}
if (totalHashes > 0) {
return hashes[totalHashes - 1];
} else if (leavesLen > 0) {
return leaves[0];
} else {
return proof[0];
}
}
function _hashPair(bytes32 a, bytes32 b) private pure returns (bytes32) {
return a < b ? _efficientHash(a, b) : _efficientHash(b, a);
}
function _efficientHash(bytes32 a, bytes32 b) private pure returns (bytes32 value) {
/// @solidity memory-safe-assembly
assembly {
mstore(0x00, a)
mstore(0x20, b)
value := keccak256(0x00, 0x40)
}
}
}
// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.2
// Creator: Chiru Labs
pragma solidity ^0.8.4;
import './IERC721A.sol';
/**
* @dev Interface of ERC721 token receiver.
*/
interface ERC721A__IERC721Receiver {
function onERC721Received(
address operator,
address from,
uint256 tokenId,
bytes calldata data
) external returns (bytes4);
}
/**
* @title ERC721A
*
* @dev Implementation of the [ERC721](https://eips.ethereum.org/EIPS/eip-721)
* Non-Fungible Token Standard, including the Metadata extension.
* Optimized for lower gas during batch mints.
*
* Token IDs are minted in sequential order (e.g. 0, 1, 2, 3, ...)
* starting from `_startTokenId()`.
*
* Assumptions:
*
* - An owner cannot have more than 2**64 - 1 (max value of uint64) of supply.
* - The maximum token ID cannot exceed 2**256 - 1 (max value of uint256).
*/
contract ERC721A is IERC721A {
// Reference type for token approval.
struct TokenApprovalRef {
address value;
}
// =============================================================
// CONSTANTS
// =============================================================
// Mask of an entry in packed address data.
uint256 private constant _BITMASK_ADDRESS_DATA_ENTRY = (1 << 64) - 1;
// The bit position of `numberMinted` in packed address data.
uint256 private constant _BITPOS_NUMBER_MINTED = 64;
// The bit position of `numberBurned` in packed address data.
uint256 private constant _BITPOS_NUMBER_BURNED = 128;
// The bit position of `aux` in packed address data.
uint256 private constant _BITPOS_AUX = 192;
// Mask of all 256 bits in packed address data except the 64 bits for `aux`.
uint256 private constant _BITMASK_AUX_COMPLEMENT = (1 << 192) - 1;
// The bit position of `startTimestamp` in packed ownership.
uint256 private constant _BITPOS_START_TIMESTAMP = 160;
// The bit mask of the `burned` bit in packed ownership.
uint256 private constant _BITMASK_BURNED = 1 << 224;
// The bit position of the `nextInitialized` bit in packed ownership.
uint256 private constant _BITPOS_NEXT_INITIALIZED = 225;
// The bit mask of the `nextInitialized` bit in packed ownership.
uint256 private constant _BITMASK_NEXT_INITIALIZED = 1 << 225;
// The bit position of `extraData` in packed ownership.
uint256 private constant _BITPOS_EXTRA_DATA = 232;
// Mask of all 256 bits in a packed ownership except the 24 bits for `extraData`.
uint256 private constant _BITMASK_EXTRA_DATA_COMPLEMENT = (1 << 232) - 1;
// The mask of the lower 160 bits for addresses.
uint256 private constant _BITMASK_ADDRESS = (1 << 160) - 1;
// The maximum `quantity` that can be minted with {_mintERC2309}.
// This limit is to prevent overflows on the address data entries.
// For a limit of 5000, a total of 3.689e15 calls to {_mintERC2309}
// is required to cause an overflow, which is unrealistic.
uint256 private constant _MAX_MINT_ERC2309_QUANTITY_LIMIT = 5000;
// The `Transfer` event signature is given by:
// `keccak256(bytes("Transfer(address,address,uint256)"))`.
bytes32 private constant _TRANSFER_EVENT_SIGNATURE =
0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef;
// =============================================================
// STORAGE
// =============================================================
// The next token ID to be minted.
uint256 private _currentIndex;
// The number of tokens burned.
uint256 private _burnCounter;
// Token name
string private _name;
// Token symbol
string private _symbol;
// Mapping from token ID to ownership details
// An empty struct value does not necessarily mean the token is unowned.
// See {_packedOwnershipOf} implementation for details.
//
// Bits Layout:
// - [0..159] `addr`
// - [160..223] `startTimestamp`
// - [224] `burned`
// - [225] `nextInitialized`
// - [232..255] `extraData`
mapping(uint256 => uint256) private _packedOwnerships;
// Mapping owner address to address data.
//
// Bits Layout:
// - [0..63] `balance`
// - [64..127] `numberMinted`
// - [128..191] `numberBurned`
// - [192..255] `aux`
mapping(address => uint256) private _packedAddressData;
// Mapping from token ID to approved address.
mapping(uint256 => TokenApprovalRef) private _tokenApprovals;
// Mapping from owner to operator approvals
mapping(address => mapping(address => bool)) private _operatorApprovals;
// =============================================================
// CONSTRUCTOR
// =============================================================
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
_currentIndex = _startTokenId();
}
// =============================================================
// TOKEN COUNTING OPERATIONS
// =============================================================
/**
* @dev Returns the starting token ID.
* To change the starting token ID, please override this function.
*/
function _startTokenId() internal view virtual returns (uint256) {
return 0;
}
/**
* @dev Returns the next token ID to be minted.
*/
function _nextTokenId() internal view virtual returns (uint256) {
return _currentIndex;
}
/**
* @dev Returns the total number of tokens in existence.
* Burned tokens will reduce the count.
* To get the total number of tokens minted, please see {_totalMinted}.
*/
function totalSupply() public view virtual override returns (uint256) {
// Counter underflow is impossible as _burnCounter cannot be incremented
// more than `_currentIndex - _startTokenId()` times.
unchecked {
return _currentIndex - _burnCounter - _startTokenId();
}
}
/**
* @dev Returns the total amount of tokens minted in the contract.
*/
function _totalMinted() internal view virtual returns (uint256) {
// Counter underflow is impossible as `_currentIndex` does not decrement,
// and it is initialized to `_startTokenId()`.
unchecked {
return _currentIndex - _startTokenId();
}
}
/**
* @dev Returns the total number of tokens burned.
*/
function _totalBurned() internal view virtual returns (uint256) {
return _burnCounter;
}
// =============================================================
// ADDRESS DATA OPERATIONS
// =============================================================
/**
* @dev Returns the number of tokens in `owner`'s account.
*/
function balanceOf(address owner) public view virtual override returns (uint256) {
if (owner == address(0)) revert BalanceQueryForZeroAddress();
return _packedAddressData[owner] & _BITMASK_ADDRESS_DATA_ENTRY;
}
/**
* Returns the number of tokens minted by `owner`.
*/
function _numberMinted(address owner) internal view returns (uint256) {
return (_packedAddressData[owner] >> _BITPOS_NUMBER_MINTED) & _BITMASK_ADDRESS_DATA_ENTRY;
}
/**
* Returns the number of tokens burned by or on behalf of `owner`.
*/
function _numberBurned(address owner) internal view returns (uint256) {
return (_packedAddressData[owner] >> _BITPOS_NUMBER_BURNED) & _BITMASK_ADDRESS_DATA_ENTRY;
}
/**
* Returns the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
*/
function _getAux(address owner) internal view returns (uint64) {
return uint64(_packedAddressData[owner] >> _BITPOS_AUX);
}
/**
* Sets the auxiliary data for `owner`. (e.g. number of whitelist mint slots used).
* If there are multiple variables, please pack them into a uint64.
*/
function _setAux(address owner, uint64 aux) internal virtual {
uint256 packed = _packedAddressData[owner];
uint256 auxCasted;
// Cast `aux` with assembly to avoid redundant masking.
assembly {
auxCasted := aux
}
packed = (packed & _BITMASK_AUX_COMPLEMENT) | (auxCasted << _BITPOS_AUX);
_packedAddressData[owner] = packed;
}
// =============================================================
// IERC165
// =============================================================
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
* to learn more about how these ids are created.
*
* This function call must use less than 30000 gas.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
// The interface IDs are constants representing the first 4 bytes
// of the XOR of all function selectors in the interface.
// See: [ERC165](https://eips.ethereum.org/EIPS/eip-165)
// (e.g. `bytes4(i.functionA.selector ^ i.functionB.selector ^ ...)`)
return
interfaceId == 0x01ffc9a7 || // ERC165 interface ID for ERC165.
interfaceId == 0x80ac58cd || // ERC165 interface ID for ERC721.
interfaceId == 0x5b5e139f; // ERC165 interface ID for ERC721Metadata.
}
// =============================================================
// IERC721Metadata
// =============================================================
/**
* @dev Returns the token collection name.
*/
function name() public view virtual override returns (string memory) {
return _name;
}
/**
* @dev Returns the token collection symbol.
*/
function symbol() public view virtual override returns (string memory) {
return _symbol;
}
/**
* @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
*/
function tokenURI(uint256 tokenId) public view virtual override returns (string memory) {
if (!_exists(tokenId)) revert URIQueryForNonexistentToken();
string memory baseURI = _baseURI();
return bytes(baseURI).length != 0 ? string(abi.encodePacked(baseURI, _toString(tokenId))) : '';
}
/**
* @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, it can be overridden in child contracts.
*/
function _baseURI() internal view virtual returns (string memory) {
return '';
}
// =============================================================
// OWNERSHIPS OPERATIONS
// =============================================================
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function ownerOf(uint256 tokenId) public view virtual override returns (address) {
return address(uint160(_packedOwnershipOf(tokenId)));
}
/**
* @dev Gas spent here starts off proportional to the maximum mint batch size.
* It gradually moves to O(1) as tokens get transferred around over time.
*/
function _ownershipOf(uint256 tokenId) internal view virtual returns (TokenOwnership memory) {
return _unpackedOwnership(_packedOwnershipOf(tokenId));
}
/**
* @dev Returns the unpacked `TokenOwnership` struct at `index`.
*/
function _ownershipAt(uint256 index) internal view virtual returns (TokenOwnership memory) {
return _unpackedOwnership(_packedOwnerships[index]);
}
/**
* @dev Initializes the ownership slot minted at `index` for efficiency purposes.
*/
function _initializeOwnershipAt(uint256 index) internal virtual {
if (_packedOwnerships[index] == 0) {
_packedOwnerships[index] = _packedOwnershipOf(index);
}
}
/**
* Returns the packed ownership data of `tokenId`.
*/
function _packedOwnershipOf(uint256 tokenId) private view returns (uint256) {
uint256 curr = tokenId;
unchecked {
if (_startTokenId() <= curr)
if (curr < _currentIndex) {
uint256 packed = _packedOwnerships[curr];
// If not burned.
if (packed & _BITMASK_BURNED == 0) {
// Invariant:
// There will always be an initialized ownership slot
// (i.e. `ownership.addr != address(0) && ownership.burned == false`)
// before an unintialized ownership slot
// (i.e. `ownership.addr == address(0) && ownership.burned == false`)
// Hence, `curr` will not underflow.
//
// We can directly compare the packed value.
// If the address is zero, packed will be zero.
while (packed == 0) {
packed = _packedOwnerships[--curr];
}
return packed;
}
}
}
revert OwnerQueryForNonexistentToken();
}
/**
* @dev Returns the unpacked `TokenOwnership` struct from `packed`.
*/
function _unpackedOwnership(uint256 packed) private pure returns (TokenOwnership memory ownership) {
ownership.addr = address(uint160(packed));
ownership.startTimestamp = uint64(packed >> _BITPOS_START_TIMESTAMP);
ownership.burned = packed & _BITMASK_BURNED != 0;
ownership.extraData = uint24(packed >> _BITPOS_EXTRA_DATA);
}
/**
* @dev Packs ownership data into a single uint256.
*/
function _packOwnershipData(address owner, uint256 flags) private view returns (uint256 result) {
assembly {
// Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
owner := and(owner, _BITMASK_ADDRESS)
// `owner | (block.timestamp << _BITPOS_START_TIMESTAMP) | flags`.
result := or(owner, or(shl(_BITPOS_START_TIMESTAMP, timestamp()), flags))
}
}
/**
* @dev Returns the `nextInitialized` flag set if `quantity` equals 1.
*/
function _nextInitializedFlag(uint256 quantity) private pure returns (uint256 result) {
// For branchless setting of the `nextInitialized` flag.
assembly {
// `(quantity == 1) << _BITPOS_NEXT_INITIALIZED`.
result := shl(_BITPOS_NEXT_INITIALIZED, eq(quantity, 1))
}
}
// =============================================================
// APPROVAL OPERATIONS
// =============================================================
/**
* @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) public virtual override {
address owner = ownerOf(tokenId);
if (_msgSenderERC721A() != owner)
if (!isApprovedForAll(owner, _msgSenderERC721A())) {
revert ApprovalCallerNotOwnerNorApproved();
}
_tokenApprovals[tokenId].value = to;
emit Approval(owner, to, tokenId);
}
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/
function getApproved(uint256 tokenId) public view virtual override returns (address) {
if (!_exists(tokenId)) revert ApprovalQueryForNonexistentToken();
return _tokenApprovals[tokenId].value;
}
/**
* @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 caller.
*
* Emits an {ApprovalForAll} event.
*/
function setApprovalForAll(address operator, bool approved) public virtual override {
_operatorApprovals[_msgSenderERC721A()][operator] = approved;
emit ApprovalForAll(_msgSenderERC721A(), operator, approved);
}
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}.
*/
function isApprovedForAll(address owner, address operator) public view virtual override returns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev Returns whether `tokenId` exists.
*
* Tokens can be managed by their owner or approved accounts via {approve} or {setApprovalForAll}.
*
* Tokens start existing when they are minted. See {_mint}.
*/
function _exists(uint256 tokenId) internal view virtual returns (bool) {
return
_startTokenId() <= tokenId &&
tokenId < _currentIndex && // If within bounds,
_packedOwnerships[tokenId] & _BITMASK_BURNED == 0; // and not burned.
}
/**
* @dev Returns whether `msgSender` is equal to `approvedAddress` or `owner`.
*/
function _isSenderApprovedOrOwner(
address approvedAddress,
address owner,
address msgSender
) private pure returns (bool result) {
assembly {
// Mask `owner` to the lower 160 bits, in case the upper bits somehow aren't clean.
owner := and(owner, _BITMASK_ADDRESS)
// Mask `msgSender` to the lower 160 bits, in case the upper bits somehow aren't clean.
msgSender := and(msgSender, _BITMASK_ADDRESS)
// `msgSender == owner || msgSender == approvedAddress`.
result := or(eq(msgSender, owner), eq(msgSender, approvedAddress))
}
}
/**
* @dev Returns the storage slot and value for the approved address of `tokenId`.
*/
function _getApprovedSlotAndAddress(uint256 tokenId)
private
view
returns (uint256 approvedAddressSlot, address approvedAddress)
{
TokenApprovalRef storage tokenApproval = _tokenApprovals[tokenId];
// The following is equivalent to `approvedAddress = _tokenApprovals[tokenId].value`.
assembly {
approvedAddressSlot := tokenApproval.slot
approvedAddress := sload(approvedAddressSlot)
}
}
// =============================================================
// TRANSFER OPERATIONS
// =============================================================
/**
* @dev Transfers `tokenId` from `from` to `to`.
*
* 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
) public virtual override {
uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);
if (address(uint160(prevOwnershipPacked)) != from) revert TransferFromIncorrectOwner();
(uint256 approvedAddressSlot, address approvedAddress) = _getApprovedSlotAndAddress(tokenId);
// The nested ifs save around 20+ gas over a compound boolean condition.
if (!_isSenderApprovedOrOwner(approvedAddress, from, _msgSenderERC721A()))
if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
if (to == address(0)) revert TransferToZeroAddress();
_beforeTokenTransfers(from, to, tokenId, 1);
// Clear approvals from the previous owner.
assembly {
if approvedAddress {
// This is equivalent to `delete _tokenApprovals[tokenId]`.
sstore(approvedAddressSlot, 0)
}
}
// Underflow of the sender's balance is impossible because we check for
// ownership above and the recipient's balance can't realistically overflow.
// Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
unchecked {
// We can directly increment and decrement the balances.
--_packedAddressData[from]; // Updates: `balance -= 1`.
++_packedAddressData[to]; // Updates: `balance += 1`.
// Updates:
// - `address` to the next owner.
// - `startTimestamp` to the timestamp of transfering.
// - `burned` to `false`.
// - `nextInitialized` to `true`.
_packedOwnerships[tokenId] = _packOwnershipData(
to,
_BITMASK_NEXT_INITIALIZED | _nextExtraData(from, to, prevOwnershipPacked)
);
// If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
if (prevOwnershipPacked & _BITMASK_NEXT_INITIALIZED == 0) {
uint256 nextTokenId = tokenId + 1;
// If the next slot's address is zero and not burned (i.e. packed value is zero).
if (_packedOwnerships[nextTokenId] == 0) {
// If the next slot is within bounds.
if (nextTokenId != _currentIndex) {
// Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
_packedOwnerships[nextTokenId] = prevOwnershipPacked;
}
}
}
}
emit Transfer(from, to, tokenId);
_afterTokenTransfers(from, to, tokenId, 1);
}
/**
* @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) public virtual override {
safeTransferFrom(from, to, tokenId, '');
}
/**
* @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 memory _data
) public virtual override {
transferFrom(from, to, tokenId);
if (to.code.length != 0)
if (!_checkContractOnERC721Received(from, to, tokenId, _data)) {
revert TransferToNonERC721ReceiverImplementer();
}
}
/**
* @dev Hook that is called before a set of serially-ordered token IDs
* are about to be transferred. This includes minting.
* And also called before burning one token.
*
* `startTokenId` - the first token ID to be transferred.
* `quantity` - the amount to be transferred.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, `tokenId` will be burned by `from`.
* - `from` and `to` are never both zero.
*/
function _beforeTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual {}
/**
* @dev Hook that is called after a set of serially-ordered token IDs
* have been transferred. This includes minting.
* And also called after one token has been burned.
*
* `startTokenId` - the first token ID to be transferred.
* `quantity` - the amount to be transferred.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, `from`'s `tokenId` has been
* transferred to `to`.
* - When `from` is zero, `tokenId` has been minted for `to`.
* - When `to` is zero, `tokenId` has been burned by `from`.
* - `from` and `to` are never both zero.
*/
function _afterTokenTransfers(
address from,
address to,
uint256 startTokenId,
uint256 quantity
) internal virtual {}
/**
* @dev Private function to invoke {IERC721Receiver-onERC721Received} on a target contract.
*
* `from` - Previous owner of the given token ID.
* `to` - Target address that will receive the token.
* `tokenId` - Token ID to be transferred.
* `_data` - Optional data to send along with the call.
*
* Returns whether the call correctly returned the expected magic value.
*/
function _checkContractOnERC721Received(
address from,
address to,
uint256 tokenId,
bytes memory _data
) private returns (bool) {
try ERC721A__IERC721Receiver(to).onERC721Received(_msgSenderERC721A(), from, tokenId, _data) returns (
bytes4 retval
) {
return retval == ERC721A__IERC721Receiver(to).onERC721Received.selector;
} catch (bytes memory reason) {
if (reason.length == 0) {
revert TransferToNonERC721ReceiverImplementer();
} else {
assembly {
revert(add(32, reason), mload(reason))
}
}
}
}
// =============================================================
// MINT OPERATIONS
// =============================================================
/**
* @dev Mints `quantity` tokens and transfers them to `to`.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `quantity` must be greater than 0.
*
* Emits a {Transfer} event for each mint.
*/
function _mint(address to, uint256 quantity) internal virtual {
uint256 startTokenId = _currentIndex;
if (quantity == 0) revert MintZeroQuantity();
_beforeTokenTransfers(address(0), to, startTokenId, quantity);
// Overflows are incredibly unrealistic.
// `balance` and `numberMinted` have a maximum limit of 2**64.
// `tokenId` has a maximum limit of 2**256.
unchecked {
// Updates:
// - `balance += quantity`.
// - `numberMinted += quantity`.
//
// We can directly add to the `balance` and `numberMinted`.
_packedAddressData[to] += quantity * ((1 << _BITPOS_NUMBER_MINTED) | 1);
// Updates:
// - `address` to the owner.
// - `startTimestamp` to the timestamp of minting.
// - `burned` to `false`.
// - `nextInitialized` to `quantity == 1`.
_packedOwnerships[startTokenId] = _packOwnershipData(
to,
_nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
);
uint256 toMasked;
uint256 end = startTokenId + quantity;
// Use assembly to loop and emit the `Transfer` event for gas savings.
// The duplicated `log4` removes an extra check and reduces stack juggling.
// The assembly, together with the surrounding Solidity code, have been
// delicately arranged to nudge the compiler into producing optimized opcodes.
assembly {
// Mask `to` to the lower 160 bits, in case the upper bits somehow aren't clean.
toMasked := and(to, _BITMASK_ADDRESS)
// Emit the `Transfer` event.
log4(
0, // Start of data (0, since no data).
0, // End of data (0, since no data).
_TRANSFER_EVENT_SIGNATURE, // Signature.
0, // `address(0)`.
toMasked, // `to`.
startTokenId // `tokenId`.
)
for {
let tokenId := add(startTokenId, 1)
} iszero(eq(tokenId, end)) {
tokenId := add(tokenId, 1)
} {
// Emit the `Transfer` event. Similar to above.
log4(0, 0, _TRANSFER_EVENT_SIGNATURE, 0, toMasked, tokenId)
}
}
if (toMasked == 0) revert MintToZeroAddress();
_currentIndex = end;
}
_afterTokenTransfers(address(0), to, startTokenId, quantity);
}
/**
* @dev Mints `quantity` tokens and transfers them to `to`.
*
* This function is intended for efficient minting only during contract creation.
*
* It emits only one {ConsecutiveTransfer} as defined in
* [ERC2309](https://eips.ethereum.org/EIPS/eip-2309),
* instead of a sequence of {Transfer} event(s).
*
* Calling this function outside of contract creation WILL make your contract
* non-compliant with the ERC721 standard.
* For full ERC721 compliance, substituting ERC721 {Transfer} event(s) with the ERC2309
* {ConsecutiveTransfer} event is only permissible during contract creation.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `quantity` must be greater than 0.
*
* Emits a {ConsecutiveTransfer} event.
*/
function _mintERC2309(address to, uint256 quantity) internal virtual {
uint256 startTokenId = _currentIndex;
if (to == address(0)) revert MintToZeroAddress();
if (quantity == 0) revert MintZeroQuantity();
if (quantity > _MAX_MINT_ERC2309_QUANTITY_LIMIT) revert MintERC2309QuantityExceedsLimit();
_beforeTokenTransfers(address(0), to, startTokenId, quantity);
// Overflows are unrealistic due to the above check for `quantity` to be below the limit.
unchecked {
// Updates:
// - `balance += quantity`.
// - `numberMinted += quantity`.
//
// We can directly add to the `balance` and `numberMinted`.
_packedAddressData[to] += quantity * ((1 << _BITPOS_NUMBER_MINTED) | 1);
// Updates:
// - `address` to the owner.
// - `startTimestamp` to the timestamp of minting.
// - `burned` to `false`.
// - `nextInitialized` to `quantity == 1`.
_packedOwnerships[startTokenId] = _packOwnershipData(
to,
_nextInitializedFlag(quantity) | _nextExtraData(address(0), to, 0)
);
emit ConsecutiveTransfer(startTokenId, startTokenId + quantity - 1, address(0), to);
_currentIndex = startTokenId + quantity;
}
_afterTokenTransfers(address(0), to, startTokenId, quantity);
}
/**
* @dev Safely mints `quantity` tokens and transfers them to `to`.
*
* Requirements:
*
* - If `to` refers to a smart contract, it must implement
* {IERC721Receiver-onERC721Received}, which is called for each safe transfer.
* - `quantity` must be greater than 0.
*
* See {_mint}.
*
* Emits a {Transfer} event for each mint.
*/
function _safeMint(
address to,
uint256 quantity,
bytes memory _data
) internal virtual {
_mint(to, quantity);
unchecked {
if (to.code.length != 0) {
uint256 end = _currentIndex;
uint256 index = end - quantity;
do {
if (!_checkContractOnERC721Received(address(0), to, index++, _data)) {
revert TransferToNonERC721ReceiverImplementer();
}
} while (index < end);
// Reentrancy protection.
if (_currentIndex != end) revert();
}
}
}
/**
* @dev Equivalent to `_safeMint(to, quantity, '')`.
*/
function _safeMint(address to, uint256 quantity) internal virtual {
_safeMint(to, quantity, '');
}
// =============================================================
// BURN OPERATIONS
// =============================================================
/**
* @dev Equivalent to `_burn(tokenId, false)`.
*/
function _burn(uint256 tokenId) internal virtual {
_burn(tokenId, false);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/
function _burn(uint256 tokenId, bool approvalCheck) internal virtual {
uint256 prevOwnershipPacked = _packedOwnershipOf(tokenId);
address from = address(uint160(prevOwnershipPacked));
(uint256 approvedAddressSlot, address approvedAddress) = _getApprovedSlotAndAddress(tokenId);
if (approvalCheck) {
// The nested ifs save around 20+ gas over a compound boolean condition.
if (!_isSenderApprovedOrOwner(approvedAddress, from, _msgSenderERC721A()))
if (!isApprovedForAll(from, _msgSenderERC721A())) revert TransferCallerNotOwnerNorApproved();
}
_beforeTokenTransfers(from, address(0), tokenId, 1);
// Clear approvals from the previous owner.
assembly {
if approvedAddress {
// This is equivalent to `delete _tokenApprovals[tokenId]`.
sstore(approvedAddressSlot, 0)
}
}
// Underflow of the sender's balance is impossible because we check for
// ownership above and the recipient's balance can't realistically overflow.
// Counter overflow is incredibly unrealistic as `tokenId` would have to be 2**256.
unchecked {
// Updates:
// - `balance -= 1`.
// - `numberBurned += 1`.
//
// We can directly decrement the balance, and increment the number burned.
// This is equivalent to `packed -= 1; packed += 1 << _BITPOS_NUMBER_BURNED;`.
_packedAddressData[from] += (1 << _BITPOS_NUMBER_BURNED) - 1;
// Updates:
// - `address` to the last owner.
// - `startTimestamp` to the timestamp of burning.
// - `burned` to `true`.
// - `nextInitialized` to `true`.
_packedOwnerships[tokenId] = _packOwnershipData(
from,
(_BITMASK_BURNED | _BITMASK_NEXT_INITIALIZED) | _nextExtraData(from, address(0), prevOwnershipPacked)
);
// If the next slot may not have been initialized (i.e. `nextInitialized == false`) .
if (prevOwnershipPacked & _BITMASK_NEXT_INITIALIZED == 0) {
uint256 nextTokenId = tokenId + 1;
// If the next slot's address is zero and not burned (i.e. packed value is zero).
if (_packedOwnerships[nextTokenId] == 0) {
// If the next slot is within bounds.
if (nextTokenId != _currentIndex) {
// Initialize the next slot to maintain correctness for `ownerOf(tokenId + 1)`.
_packedOwnerships[nextTokenId] = prevOwnershipPacked;
}
}
}
}
emit Transfer(from, address(0), tokenId);
_afterTokenTransfers(from, address(0), tokenId, 1);
// Overflow not possible, as _burnCounter cannot be exceed _currentIndex times.
unchecked {
_burnCounter++;
}
}
// =============================================================
// EXTRA DATA OPERATIONS
// =============================================================
/**
* @dev Directly sets the extra data for the ownership data `index`.
*/
function _setExtraDataAt(uint256 index, uint24 extraData) internal virtual {
uint256 packed = _packedOwnerships[index];
if (packed == 0) revert OwnershipNotInitializedForExtraData();
uint256 extraDataCasted;
// Cast `extraData` with assembly to avoid redundant masking.
assembly {
extraDataCasted := extraData
}
packed = (packed & _BITMASK_EXTRA_DATA_COMPLEMENT) | (extraDataCasted << _BITPOS_EXTRA_DATA);
_packedOwnerships[index] = packed;
}
/**
* @dev Called during each token transfer to set the 24bit `extraData` field.
* Intended to be overridden by the cosumer contract.
*
* `previousExtraData` - the value of `extraData` before transfer.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, `from`'s `tokenId` will be
* transferred to `to`.
* - When `from` is zero, `tokenId` will be minted for `to`.
* - When `to` is zero, `tokenId` will be burned by `from`.
* - `from` and `to` are never both zero.
*/
function _extraData(
address from,
address to,
uint24 previousExtraData
) internal view virtual returns (uint24) {}
/**
* @dev Returns the next extra data for the packed ownership data.
* The returned result is shifted into position.
*/
function _nextExtraData(
address from,
address to,
uint256 prevOwnershipPacked
) private view returns (uint256) {
uint24 extraData = uint24(prevOwnershipPacked >> _BITPOS_EXTRA_DATA);
return uint256(_extraData(from, to, extraData)) << _BITPOS_EXTRA_DATA;
}
// =============================================================
// OTHER OPERATIONS
// =============================================================
/**
* @dev Returns the message sender (defaults to `msg.sender`).
*
* If you are writing GSN compatible contracts, you need to override this function.
*/
function _msgSenderERC721A() internal view virtual returns (address) {
return msg.sender;
}
/**
* @dev Converts a uint256 to its ASCII string decimal representation.
*/
function _toString(uint256 value) internal pure virtual returns (string memory str) {
assembly {
// The maximum value of a uint256 contains 78 digits (1 byte per digit),
// but we allocate 0x80 bytes to keep the free memory pointer 32-byte word aligned.
// We will need 1 32-byte word to store the length,
// and 3 32-byte words to store a maximum of 78 digits. Total: 0x20 + 3 * 0x20 = 0x80.
str := add(mload(0x40), 0x80)
// Update the free memory pointer to allocate.
mstore(0x40, str)
// Cache the end of the memory to calculate the length later.
let end := str
// We write the string from rightmost digit to leftmost digit.
// The following is essentially a do-while loop that also handles the zero case.
// prettier-ignore
for { let temp := value } 1 {} {
str := sub(str, 1)
// Write the character to the pointer.
// The ASCII index of the '0' character is 48.
mstore8(str, add(48, mod(temp, 10)))
// Keep dividing `temp` until zero.
temp := div(temp, 10)
// prettier-ignore
if iszero(temp) { break }
}
let length := sub(end, str)
// Move the pointer 32 bytes leftwards to make room for the length.
str := sub(str, 0x20)
// Store the length.
mstore(str, length)
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../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.
*
* By default, the owner account will be the one that deploys the contract. 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;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @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 {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing 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 {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_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);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
abstract contract Pausable is Context {
/**
* @dev Emitted when the pause is triggered by `account`.
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by `account`.
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state.
*/
constructor() {
_paused = false;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*
* Requirements:
*
* - The contract must not be paused.
*/
modifier whenNotPaused() {
_requireNotPaused();
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*
* Requirements:
*
* - The contract must be paused.
*/
modifier whenPaused() {
_requirePaused();
_;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view virtual returns (bool) {
return _paused;
}
/**
* @dev Throws if the contract is paused.
*/
function _requireNotPaused() internal view virtual {
require(!paused(), "Pausable: paused");
}
/**
* @dev Throws if the contract is not paused.
*/
function _requirePaused() internal view virtual {
require(paused(), "Pausable: not paused");
}
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - The contract must not be paused.
*/
function _pause() internal virtual whenNotPaused {
_paused = true;
emit Paused(_msgSender());
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - The contract must be paused.
*/
function _unpause() internal virtual whenPaused {
_paused = false;
emit Unpaused(_msgSender());
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/common/ERC2981.sol)
pragma solidity ^0.8.0;
import "../../interfaces/IERC2981.sol";
import "../../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 EIP. Marketplaces are expected to
* voluntarily pay royalties together with sales, but note that this standard is not yet widely supported.
*
* _Available since v4.5._
*/
abstract contract ERC2981 is IERC2981, ERC165 {
struct RoyaltyInfo {
address receiver;
uint96 royaltyFraction;
}
RoyaltyInfo private _defaultRoyaltyInfo;
mapping(uint256 => RoyaltyInfo) private _tokenRoyaltyInfo;
/**
* @dev See {IERC165-supportsInterface}.
*/
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 override returns (address, uint256) {
RoyaltyInfo memory royalty = _tokenRoyaltyInfo[_tokenId];
if (royalty.receiver == address(0)) {
royalty = _defaultRoyaltyInfo;
}
uint256 royaltyAmount = (_salePrice * royalty.royaltyFraction) / _feeDenominator();
return (royalty.receiver, 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 {
require(feeNumerator <= _feeDenominator(), "ERC2981: royalty fee will exceed salePrice");
require(receiver != address(0), "ERC2981: invalid receiver");
_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 {
require(feeNumerator <= _feeDenominator(), "ERC2981: royalty fee will exceed salePrice");
require(receiver != address(0), "ERC2981: Invalid parameters");
_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];
}
}
// SPDX-License-Identifier: MIT
// ERC721A Contracts v4.2.2
// Creator: Chiru Labs
pragma solidity ^0.8.4;
/**
* @dev Interface of ERC721A.
*/
interface IERC721A {
/**
* The caller must own the token or be an approved operator.
*/
error ApprovalCallerNotOwnerNorApproved();
/**
* The token does not exist.
*/
error ApprovalQueryForNonexistentToken();
/**
* Cannot query the balance for the zero address.
*/
error BalanceQueryForZeroAddress();
/**
* Cannot mint to the zero address.
*/
error MintToZeroAddress();
/**
* The quantity of tokens minted must be more than zero.
*/
error MintZeroQuantity();
/**
* The token does not exist.
*/
error OwnerQueryForNonexistentToken();
/**
* The caller must own the token or be an approved operator.
*/
error TransferCallerNotOwnerNorApproved();
/**
* The token must be owned by `from`.
*/
error TransferFromIncorrectOwner();
/**
* Cannot safely transfer to a contract that does not implement the
* ERC721Receiver interface.
*/
error TransferToNonERC721ReceiverImplementer();
/**
* Cannot transfer to the zero address.
*/
error TransferToZeroAddress();
/**
* The token does not exist.
*/
error URIQueryForNonexistentToken();
/**
* The `quantity` minted with ERC2309 exceeds the safety limit.
*/
error MintERC2309QuantityExceedsLimit();
/**
* The `extraData` cannot be set on an unintialized ownership slot.
*/
error OwnershipNotInitializedForExtraData();
// =============================================================
// STRUCTS
// =============================================================
struct TokenOwnership {
// The address of the owner.
address addr;
// Stores the start time of ownership with minimal overhead for tokenomics.
uint64 startTimestamp;
// Whether the token has been burned.
bool burned;
// Arbitrary data similar to `startTimestamp` that can be set via {_extraData}.
uint24 extraData;
}
// =============================================================
// TOKEN COUNTERS
// =============================================================
/**
* @dev Returns the total number of tokens in existence.
* Burned tokens will reduce the count.
* To get the total number of tokens minted, please see {_totalMinted}.
*/
function totalSupply() external view returns (uint256);
// =============================================================
// IERC165
// =============================================================
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* [EIP section](https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified)
* to learn more about how these ids are created.
*
* This function call must use less than 30000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
// =============================================================
// IERC721
// =============================================================
/**
* @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`,
* checking first that contract recipients are aware of the ERC721 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 be 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,
bytes calldata data
) external;
/**
* @dev Equivalent to `safeTransferFrom(from, to, tokenId, '')`.
*/
function safeTransferFrom(
address from,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` from `from` to `to`.
*
* WARNING: Usage of this method is discouraged, use {safeTransferFrom}
* whenever possible.
*
* 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 caller.
*
* 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);
// =============================================================
// IERC721Metadata
// =============================================================
/**
* @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);
// =============================================================
// IERC2309
// =============================================================
/**
* @dev Emitted when tokens in `fromTokenId` to `toTokenId`
* (inclusive) is transferred from `from` to `to`, as defined in the
* [ERC2309](https://eips.ethereum.org/EIPS/eip-2309) standard.
*
* See {_mintERC2309} for more details.
*/
event ConsecutiveTransfer(uint256 indexed fromTokenId, uint256 toTokenId, address indexed from, address indexed to);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @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;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (interfaces/IERC2981.sol)
pragma solidity ^0.8.0;
import "../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.
*
* _Available since v4.5._
*/
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.
*/
function royaltyInfo(uint256 tokenId, uint256 salePrice)
external
view
returns (address receiver, uint256 royaltyAmount);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
pragma solidity ^0.8.0;
import "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC165 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);
* }
* ```
*
* Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* 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[EIP 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);
}