// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)pragmasolidity ^0.8.1;/**
* @dev Collection of functions related to the address type
*/libraryAddress{
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/functionisContract(address account) internalviewreturns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0// for contracts in construction, since the code is only stored at the end// of the constructor execution.return account.code.length>0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/functionsendValue(addresspayable recipient, uint256 amount) internal{
require(address(this).balance>= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/functionfunctionCall(address target, bytesmemory data) internalreturns (bytesmemory) {
return functionCallWithValue(target, data, 0, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/functionfunctionCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value
) internalreturns (bytesmemory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/functionfunctionCallWithValue(address target,
bytesmemory data,
uint256 value,
stringmemory errorMessage
) internalreturns (bytesmemory) {
require(address(this).balance>= value, "Address: insufficient balance for call");
(bool success, bytesmemory returndata) = target.call{value: value}(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/functionfunctionStaticCall(address target, bytesmemory data) internalviewreturns (bytesmemory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/functionfunctionStaticCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
(bool success, bytesmemory returndata) = target.staticcall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/functionfunctionDelegateCall(address target, bytesmemory data) internalreturns (bytesmemory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/functionfunctionDelegateCall(address target,
bytesmemory data,
stringmemory errorMessage
) internalreturns (bytesmemory) {
(bool success, bytesmemory returndata) = target.delegatecall(data);
return verifyCallResultFromTarget(target, success, returndata, errorMessage);
}
/**
* @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
* the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
*
* _Available since v4.8._
*/functionverifyCallResultFromTarget(address target,
bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalviewreturns (bytesmemory) {
if (success) {
if (returndata.length==0) {
// only check isContract if the call was successful and the return data is empty// otherwise we already know that it was a contractrequire(isContract(target), "Address: call to non-contract");
}
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
/**
* @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason or using the provided one.
*
* _Available since v4.3._
*/functionverifyCallResult(bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalpurereturns (bytesmemory) {
if (success) {
return returndata;
} else {
_revert(returndata, errorMessage);
}
}
function_revert(bytesmemory returndata, stringmemory errorMessage) privatepure{
// Look for revert reason and bubble it up if presentif (returndata.length>0) {
// The easiest way to bubble the revert reason is using memory via assembly/// @solidity memory-safe-assemblyassembly {
let returndata_size :=mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
Contract Source Code
File 2 of 18: Context.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)pragmasolidity ^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.
*/abstractcontractContext{
function_msgSender() internalviewvirtualreturns (address) {
returnmsg.sender;
}
function_msgData() internalviewvirtualreturns (bytescalldata) {
returnmsg.data;
}
}
Contract Source Code
File 3 of 18: Counters.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)pragmasolidity ^0.8.0;/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
*/libraryCounters{
structCounter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add// this feature: see https://github.com/ethereum/solidity/issues/4637uint256 _value; // default: 0
}
functioncurrent(Counter storage counter) internalviewreturns (uint256) {
return counter._value;
}
functionincrement(Counter storage counter) internal{
unchecked {
counter._value +=1;
}
}
functiondecrement(Counter storage counter) internal{
uint256 value = counter._value;
require(value >0, "Counter: decrement overflow");
unchecked {
counter._value = value -1;
}
}
functionreset(Counter storage counter) internal{
counter._value =0;
}
functionsetValue(Counter storage counter, uint256 _new) internal{
counter._value = _new;
}
}
// SPDX-License-Identifier: MITpragmasolidity ^0.8.17;import"@openzeppelin/contracts/token/ERC721/ERC721.sol";
import"@openzeppelin/contracts/token/ERC721/extensions/ERC721Burnable.sol";
import"@openzeppelin/contracts/access/Ownable.sol";
import"@openzeppelin/contracts/utils/Counters.sol";
import"@openzeppelin/contracts/token/ERC20/IERC20.sol";
import"@openzeppelin/contracts/token/common/ERC2981.sol";
import"./Dino.sol";
contractDinoEggisERC721, ERC721Burnable, Ownable, ERC2981{
usingCountersforCounters.Counter;
usingStringsforuint256;
Hatch public hatchPhase;
States public currentState;
IERC20 public dinoToken;
DinoNFT public dinoHatchery;
//6 counters, 1 for egg, 5 for dino
Counters.Counter public _tokenIDcounter;
Counters.Counter[5] private _base;
//lets enumerate tokenIDs by owner - [owner][index => tokenID]mapping(address=>mapping(uint256=>uint256)) public _ownedTokens;
//WLmapping(address=>bool) public isVIP;
mapping(address=>bool) public isBigStaker;
mapping(address=>bool) public isSmallStaker;
mapping(address=>uint) public vipMintCount;
mapping(address=>uint) public stakersMintCount;
mapping(address=>uint) public publicMintCount;
mapping(uint=>bool) public burnedIDs;
uintpublic vipMintLimit =10;
uintpublic stakerLimits =3;
uintpublic pubMintLimit =2;
uintpublic pubMintThrottle =2;
uintpublic totalMinted;
uint maxSupply =10000;
stringpublic baseURI;
uint256 cost =.0333ether;
uintprivate nonce;
address dinoWallet;
enumStates {
bigStakeMint,
littleStakeMint,
publicMint
}
enumHatch {
cannotHatch,
canHatch
}
constructor(address dino,
address _dinoToken,
address _royaltyWallet,
address _dinoWallet
)
ERC721("Dino Mystery Egg", "Degg")
{
_setDefaultRoyalty(_royaltyWallet, 1000);
dinoWallet = _dinoWallet;
dinoToken = IERC20(_dinoToken);
dinoHatchery = DinoNFT(dino);
currentState = States.bigStakeMint;
hatchPhase = Hatch.cannotHatch;
}
/*phase management */functioncanHatch() publiconlyOwner{
if(hatchPhase == Hatch.cannotHatch){
hatchPhase = Hatch.canHatch;
}
}
functioncannotHatch() publiconlyOwner{
if(hatchPhase == Hatch.canHatch){
hatchPhase = Hatch.cannotHatch;
}
}
functionforwardState() publiconlyOwner{
if(currentState == States.bigStakeMint) {
currentState = States.littleStakeMint;
} elseif(currentState == States.littleStakeMint) {
currentState = States.publicMint;
}
}
functionbackState() publiconlyOwner{
if(currentState == States.publicMint){
currentState = States.littleStakeMint;
} elseif(currentState == States.littleStakeMint){
currentState = States.bigStakeMint;
}
}
/* end *//*WL section */functionaddVIPs(address[] calldata _vip) publiconlyOwner{
for(uint i =0; i < _vip.length; i++){
isVIP[_vip[i]] =true;
}
}
functionaddBigStakers(address[] calldata _bigStaker) publiconlyOwner{
for(uint i =0; i < _bigStaker.length; i++){
isBigStaker[_bigStaker[i]] =true;
}
}
functionaddSmallStakers(address[] calldata _smallStakers) publiconlyOwner{
for(uint i =0; i < _smallStakers.length; i++){
isSmallStaker[_smallStakers[i]] =true;
}
}
/* end *///requires token approvalfunctionvipAndTeamMint(uint quantity) public{
require(isVIP[msg.sender] ==true,"you're up to no good if you're seeing this.");
require(vipMintCount[msg.sender] + quantity <= vipMintLimit, "that's all you get from this mint function");
require(dinoToken.transferFrom(msg.sender, address(this), (1000*10**18) * quantity),"either no approval or not enough dino");
for(uint i =0; i < quantity; i++){
//increase tokenID counter to start at one
_tokenIDcounter.increment();
//current tokenIDuint tokenID = _tokenIDcounter.current();
//vip mint count
vipMintCount[msg.sender] ++;
//mint the egg to msg sender
_safeMint(msg.sender, tokenID);
//increase total minted counter
totalMinted++;
//emit egg mint eventemit eggMinted(msg.sender, tokenID);
_ownedTokens[msg.sender][i] = tokenID;
}
}
//must have token approval prior to callingfunctionstakersMint(uint quantity) public{
require(currentState != States.publicMint,"private sales closed");
require(stakersMintCount[msg.sender] + quantity <= stakerLimits, "you've minted the max amount for this phase");
require(dinoToken.transferFrom(msg.sender, address(this), (1000*10**18) * quantity),"either no approval or not enough dino");
if(currentState == States.bigStakeMint){
require(isBigStaker[msg.sender] ==true, "youre not a big staker. check back later");
} elseif(currentState == States.littleStakeMint) {
require(dinoToken.balanceOf(msg.sender) >=10000*10**18|| isSmallStaker[msg.sender] ==true, "not staking or have enough dino");
}
//loop through quantity amount and begin egg minting processfor(uint i =0; i < quantity; i++){
stakersMintCount[msg.sender] ++;
//increase tokenID counter
_tokenIDcounter.increment();
//current tokenIDuint tokenID = _tokenIDcounter.current();
//mint the egg to msg sender
_safeMint(msg.sender, tokenID);
//increase total minted counter
totalMinted++;
//emit egg mint event
_ownedTokens[msg.sender][i] = tokenID;
emit eggMinted(msg.sender, tokenID);
}
}
//requires token approvalfunctionpublicMint(uint quantity) public{
require(currentState != States.bigStakeMint && currentState != States.littleStakeMint, "public sale has not opened yet.");
//cap max supply at 10_000require(_tokenIDcounter.current() <= maxSupply, "max supply met.");
//move dino tokens from caller to contract for batch burningrequire(dinoToken.transferFrom(msg.sender, address(this), (1000*10**18) * quantity),"either no approval or not enough dino");
//max 2 per wallet on public salerequire(publicMintCount[msg.sender] + quantity <= pubMintLimit,"you've minted max for public");
for(uint i =0; i < quantity; i++){
publicMintCount[msg.sender] ++;
//increase tokenID counter
_tokenIDcounter.increment();
//current tokenIDuint tokenID = _tokenIDcounter.current();
//mint the egg to msg sender
_safeMint(msg.sender, tokenID);
//increase total minted counter
totalMinted++;
//emit egg mint event
_ownedTokens[msg.sender][i] = tokenID;
emit eggMinted(msg.sender, tokenID);
}
}
//charges ether functionhatchEgg(uint _eggID) publicpayable{
//gotta own the egg if you wanna hatch it require(ownerOf(_eggID) ==msg.sender, "what are u doing?");
require(hatchPhase == Hatch.canHatch,"its not time to hatch your egg yet");
require(msg.value>= cost,"not enough ether sent");
_burn(_eggID);
burnedIDs[_eggID] =true;
emit eggBurn(msg.sender, _eggID);
randomHatch(msg.sender);
emit numberRequested(_eggID, msg.sender);
}
functionsetBaseURI(stringmemory _newURI) publiconlyOwner{
baseURI = _newURI;
}
function_baseURI() internalviewvirtualoverridereturns (stringmemory)
{
return baseURI;
}
functiontokenURI(uint256 tokenId)
publicviewvirtualoverridereturns (stringmemory)
{
require(
_exists(tokenId),
"ERC721Metadata: URI query for nonexistent token"
);
stringmemory currentBaseURI = _baseURI();
returnbytes(currentBaseURI).length>0
? string(abi.encodePacked(currentBaseURI))
: "";
}
//transfers dino from contract to dead wallet. no other options.functionburnDinoTokens() publiconlyOwner{
uint256 burnBalance = dinoToken.balanceOf(address(this));
dinoToken.transfer(address(0x000000000000000000000000000000000000dEaD), burnBalance);
}
//withdraws ether to contract ownerfunctionwithdrawEther() publiconlyOwner{
uint256 contractEthBal =address(this).balance;
payable(dinoWallet).transfer(contractEthBal);
}
functionsetCost(uint _newCost) publiconlyOwner{
cost = _newCost;
}
functionsetPubLimit(uint _amount) publiconlyOwner{
pubMintLimit = _amount;
}
functionsetPubThrottle(uint _amount) publiconlyOwner{
pubMintThrottle = _amount;
}
functionsetStakerLimits(uint _amount) publiconlyOwner{
stakerLimits = _amount;
}
functionrandomHatch(address _hatchee) internal{
uint word =uint256(keccak256(abi.encodePacked(block.timestamp, blockhash(block.number-1), block.coinbase, msg.sender, nonce++)));
uint range = (word %5) +1;
emit numberResolved(range, msg.sender);
while(true) {
if(_base[range -1].current() <2000) {
uint startingIndex = (range -1) *2000+1; // 1, 2001, 4001 etc. uint tokenid = _base[range -1].current() + startingIndex;
_base[range -1].increment();
dinoHatchery.indexHatcher(_hatchee, tokenid);
emit hatchSent(_hatchee, tokenid);
break;
}
else {
word =uint256(keccak256(abi.encodePacked(word)));
range = (word %5) +1;
}
}
}
//override to make royalties and 721 get alongfunctionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverride(ERC2981, ERC721) returns (bool) {
return interfaceId ==type(IERC2981).interfaceId||super.supportsInterface(interfaceId);
}
/* events */eventeggMinted
(address receiver,
uint eggID
);
eventeggBurn
(address burner,
uint eggID
);
eventhatchSent
(address receiver,
uint dinoID
);
eventnumberRequested(uintindexed eggID,
addressindexed caller
);
eventnumberResolved(uintindexed number,
addressindexed caller
);
//neo was here
}
Contract Source Code
File 6 of 18: ERC165.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)pragmasolidity ^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.
*/abstractcontractERC165isIERC165{
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverridereturns (bool) {
return interfaceId ==type(IERC165).interfaceId;
}
}
Contract Source Code
File 7 of 18: ERC2981.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.7.0) (token/common/ERC2981.sol)pragmasolidity ^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._
*/abstractcontractERC2981isIERC2981, ERC165{
structRoyaltyInfo {
address receiver;
uint96 royaltyFraction;
}
RoyaltyInfo private _defaultRoyaltyInfo;
mapping(uint256=> RoyaltyInfo) private _tokenRoyaltyInfo;
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverride(IERC165, ERC165) returns (bool) {
return interfaceId ==type(IERC2981).interfaceId||super.supportsInterface(interfaceId);
}
/**
* @inheritdoc IERC2981
*/functionroyaltyInfo(uint256 _tokenId, uint256 _salePrice) publicviewvirtualoverridereturns (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() internalpurevirtualreturns (uint96) {
return10000;
}
/**
* @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) internalvirtual{
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() internalvirtual{
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
) internalvirtual{
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) internalvirtual{
delete _tokenRoyaltyInfo[tokenId];
}
}
Contract Source Code
File 8 of 18: ERC721.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/ERC721.sol)pragmasolidity ^0.8.0;import"./IERC721.sol";
import"./IERC721Receiver.sol";
import"./extensions/IERC721Metadata.sol";
import"../../utils/Address.sol";
import"../../utils/Context.sol";
import"../../utils/Strings.sol";
import"../../utils/introspection/ERC165.sol";
/**
* @dev Implementation of https://eips.ethereum.org/EIPS/eip-721[ERC721] Non-Fungible Token Standard, including
* the Metadata extension, but not including the Enumerable extension, which is available separately as
* {ERC721Enumerable}.
*/contractERC721isContext, ERC165, IERC721, IERC721Metadata{
usingAddressforaddress;
usingStringsforuint256;
// Token namestringprivate _name;
// Token symbolstringprivate _symbol;
// Mapping from token ID to owner addressmapping(uint256=>address) private _owners;
// Mapping owner address to token countmapping(address=>uint256) private _balances;
// Mapping from token ID to approved addressmapping(uint256=>address) private _tokenApprovals;
// Mapping from owner to operator approvalsmapping(address=>mapping(address=>bool)) private _operatorApprovals;
/**
* @dev Initializes the contract by setting a `name` and a `symbol` to the token collection.
*/constructor(stringmemory name_, stringmemory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId) publicviewvirtualoverride(ERC165, IERC165) returns (bool) {
return
interfaceId ==type(IERC721).interfaceId||
interfaceId ==type(IERC721Metadata).interfaceId||super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721-balanceOf}.
*/functionbalanceOf(address owner) publicviewvirtualoverridereturns (uint256) {
require(owner !=address(0), "ERC721: address zero is not a valid owner");
return _balances[owner];
}
/**
* @dev See {IERC721-ownerOf}.
*/functionownerOf(uint256 tokenId) publicviewvirtualoverridereturns (address) {
address owner = _ownerOf(tokenId);
require(owner !=address(0), "ERC721: invalid token ID");
return owner;
}
/**
* @dev See {IERC721Metadata-name}.
*/functionname() publicviewvirtualoverridereturns (stringmemory) {
return _name;
}
/**
* @dev See {IERC721Metadata-symbol}.
*/functionsymbol() publicviewvirtualoverridereturns (stringmemory) {
return _symbol;
}
/**
* @dev See {IERC721Metadata-tokenURI}.
*/functiontokenURI(uint256 tokenId) publicviewvirtualoverridereturns (stringmemory) {
_requireMinted(tokenId);
stringmemory baseURI = _baseURI();
returnbytes(baseURI).length>0 ? string(abi.encodePacked(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() internalviewvirtualreturns (stringmemory) {
return"";
}
/**
* @dev See {IERC721-approve}.
*/functionapprove(address to, uint256 tokenId) publicvirtualoverride{
address owner = ERC721.ownerOf(tokenId);
require(to != owner, "ERC721: approval to current owner");
require(
_msgSender() == owner || isApprovedForAll(owner, _msgSender()),
"ERC721: approve caller is not token owner or approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/functiongetApproved(uint256 tokenId) publicviewvirtualoverridereturns (address) {
_requireMinted(tokenId);
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/functionsetApprovalForAll(address operator, bool approved) publicvirtualoverride{
_setApprovalForAll(_msgSender(), operator, approved);
}
/**
* @dev See {IERC721-isApprovedForAll}.
*/functionisApprovedForAll(address owner, address operator) publicviewvirtualoverridereturns (bool) {
return _operatorApprovals[owner][operator];
}
/**
* @dev See {IERC721-transferFrom}.
*/functiontransferFrom(addressfrom,
address to,
uint256 tokenId
) publicvirtualoverride{
//solhint-disable-next-line max-line-lengthrequire(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_transfer(from, to, tokenId);
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId
) publicvirtualoverride{
safeTransferFrom(from, to, tokenId, "");
}
/**
* @dev See {IERC721-safeTransferFrom}.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytesmemory data
) publicvirtualoverride{
require(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_safeTransfer(from, to, tokenId, data);
}
/**
* @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.
*
* `data` is additional data, it has no specified format and it is sent in call to `to`.
*
* This internal function is equivalent to {safeTransferFrom}, and can be used to e.g.
* implement alternative mechanisms to perform token transfer, such as signature-based.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `tokenId` token must exist and be owned by `from`.
* - 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(addressfrom,
address to,
uint256 tokenId,
bytesmemory data
) internalvirtual{
_transfer(from, to, tokenId);
require(_checkOnERC721Received(from, to, tokenId, data), "ERC721: transfer to non ERC721Receiver implementer");
}
/**
* @dev Returns the owner of the `tokenId`. Does NOT revert if token doesn't exist
*/function_ownerOf(uint256 tokenId) internalviewvirtualreturns (address) {
return _owners[tokenId];
}
/**
* @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 (`_mint`),
* and stop existing when they are burned (`_burn`).
*/function_exists(uint256 tokenId) internalviewvirtualreturns (bool) {
return _ownerOf(tokenId) !=address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/function_isApprovedOrOwner(address spender, uint256 tokenId) internalviewvirtualreturns (bool) {
address owner = ERC721.ownerOf(tokenId);
return (spender == owner || isApprovedForAll(owner, spender) || getApproved(tokenId) == spender);
}
/**
* @dev Safely mints `tokenId` and transfers it to `to`.
*
* 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) internalvirtual{
_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,
bytesmemory data
) internalvirtual{
_mint(to, tokenId);
require(
_checkOnERC721Received(address(0), to, tokenId, data),
"ERC721: transfer to non ERC721Receiver implementer"
);
}
/**
* @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) internalvirtual{
require(to !=address(0), "ERC721: mint to the zero address");
require(!_exists(tokenId), "ERC721: token already minted");
_beforeTokenTransfer(address(0), to, tokenId, 1);
// Check that tokenId was not minted by `_beforeTokenTransfer` hookrequire(!_exists(tokenId), "ERC721: token already minted");
unchecked {
// Will not overflow unless all 2**256 token ids are minted to the same owner.// Given that tokens are minted one by one, it is impossible in practice that// this ever happens. Might change if we allow batch minting.// The ERC fails to describe this case.
_balances[to] +=1;
}
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
_afterTokenTransfer(address(0), to, tokenId, 1);
}
/**
* @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) internalvirtual{
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId, 1);
// Update ownership in case tokenId was transferred by `_beforeTokenTransfer` hook
owner = ERC721.ownerOf(tokenId);
// Clear approvalsdelete _tokenApprovals[tokenId];
unchecked {
// Cannot overflow, as that would require more tokens to be burned/transferred// out than the owner initially received through minting and transferring in.
_balances[owner] -=1;
}
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
_afterTokenTransfer(owner, address(0), tokenId, 1);
}
/**
* @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(addressfrom,
address to,
uint256 tokenId
) internalvirtual{
require(ERC721.ownerOf(tokenId) ==from, "ERC721: transfer from incorrect owner");
require(to !=address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId, 1);
// Check that tokenId was not transferred by `_beforeTokenTransfer` hookrequire(ERC721.ownerOf(tokenId) ==from, "ERC721: transfer from incorrect owner");
// Clear approvals from the previous ownerdelete _tokenApprovals[tokenId];
unchecked {
// `_balances[from]` cannot overflow for the same reason as described in `_burn`:// `from`'s balance is the number of token held, which is at least one before the current// transfer.// `_balances[to]` could overflow in the conditions described in `_mint`. That would require// all 2**256 token ids to be minted, which in practice is impossible.
_balances[from] -=1;
_balances[to] +=1;
}
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
_afterTokenTransfer(from, to, tokenId, 1);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits an {Approval} event.
*/function_approve(address to, uint256 tokenId) internalvirtual{
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @dev Approve `operator` to operate on all of `owner` tokens
*
* Emits an {ApprovalForAll} event.
*/function_setApprovalForAll(address owner,
address operator,
bool approved
) internalvirtual{
require(owner != operator, "ERC721: approve to caller");
_operatorApprovals[owner][operator] = approved;
emit ApprovalForAll(owner, operator, approved);
}
/**
* @dev Reverts if the `tokenId` has not been minted yet.
*/function_requireMinted(uint256 tokenId) internalviewvirtual{
require(_exists(tokenId), "ERC721: invalid token ID");
}
/**
* @dev Internal function to invoke {IERC721Receiver-onERC721Received} on a target address.
* The call is not executed if the target address is not a contract.
*
* @param from address representing the previous owner of the given token ID
* @param to target address that will receive the tokens
* @param tokenId uint256 ID of the token to be transferred
* @param data bytes optional data to send along with the call
* @return bool whether the call correctly returned the expected magic value
*/function_checkOnERC721Received(addressfrom,
address to,
uint256 tokenId,
bytesmemory data
) privatereturns (bool) {
if (to.isContract()) {
try IERC721Receiver(to).onERC721Received(_msgSender(), from, tokenId, data) returns (bytes4 retval) {
return retval == IERC721Receiver.onERC721Received.selector;
} catch (bytesmemory reason) {
if (reason.length==0) {
revert("ERC721: transfer to non ERC721Receiver implementer");
} else {
/// @solidity memory-safe-assemblyassembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
returntrue;
}
}
/**
* @dev Hook that is called before any token transfer. This includes minting and burning. If {ERC721Consecutive} is
* used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s tokens will be transferred to `to`.
* - When `from` is zero, the tokens will be minted for `to`.
* - When `to` is zero, ``from``'s tokens will be burned.
* - `from` and `to` are never both zero.
* - `batchSize` is non-zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256, /* firstTokenId */uint256 batchSize
) internalvirtual{
if (batchSize >1) {
if (from!=address(0)) {
_balances[from] -= batchSize;
}
if (to !=address(0)) {
_balances[to] += batchSize;
}
}
}
/**
* @dev Hook that is called after any token transfer. This includes minting and burning. If {ERC721Consecutive} is
* used, the hook may be called as part of a consecutive (batch) mint, as indicated by `batchSize` greater than 1.
*
* Calling conditions:
*
* - When `from` and `to` are both non-zero, ``from``'s tokens were transferred to `to`.
* - When `from` is zero, the tokens were minted for `to`.
* - When `to` is zero, ``from``'s tokens were burned.
* - `from` and `to` are never both zero.
* - `batchSize` is non-zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_afterTokenTransfer(addressfrom,
address to,
uint256 firstTokenId,
uint256 batchSize
) internalvirtual{}
}
Contract Source Code
File 9 of 18: ERC721Burnable.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/extensions/ERC721Burnable.sol)pragmasolidity ^0.8.0;import"../ERC721.sol";
import"../../../utils/Context.sol";
/**
* @title ERC721 Burnable Token
* @dev ERC721 Token that can be burned (destroyed).
*/abstractcontractERC721BurnableisContext, ERC721{
/**
* @dev Burns `tokenId`. See {ERC721-_burn}.
*
* Requirements:
*
* - The caller must own `tokenId` or be an approved operator.
*/functionburn(uint256 tokenId) publicvirtual{
//solhint-disable-next-line max-line-lengthrequire(_isApprovedOrOwner(_msgSender(), tokenId), "ERC721: caller is not token owner or approved");
_burn(tokenId);
}
}
Contract Source Code
File 10 of 18: IERC165.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)pragmasolidity ^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}.
*/interfaceIERC165{
/**
* @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.
*/functionsupportsInterface(bytes4 interfaceId) externalviewreturns (bool);
}
Contract Source Code
File 11 of 18: IERC20.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)pragmasolidity ^0.8.0;/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/interfaceIERC20{
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/eventTransfer(addressindexedfrom, addressindexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/eventApproval(addressindexed owner, addressindexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/functiontotalSupply() externalviewreturns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/functionbalanceOf(address account) externalviewreturns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/functiontransfer(address to, uint256 amount) externalreturns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/functionallowance(address owner, address spender) externalviewreturns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/functionapprove(address spender, uint256 amount) externalreturns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/functiontransferFrom(addressfrom,
address to,
uint256 amount
) externalreturns (bool);
}
Contract Source Code
File 12 of 18: IERC2981.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.6.0) (interfaces/IERC2981.sol)pragmasolidity ^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._
*/interfaceIERC2981isIERC165{
/**
* @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.
*/functionroyaltyInfo(uint256 tokenId, uint256 salePrice)
externalviewreturns (address receiver, uint256 royaltyAmount);
}
Contract Source Code
File 13 of 18: IERC721.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC721/IERC721.sol)pragmasolidity ^0.8.0;import"../../utils/introspection/IERC165.sol";
/**
* @dev Required interface of an ERC721 compliant contract.
*/interfaceIERC721isIERC165{
/**
* @dev Emitted when `tokenId` token is transferred from `from` to `to`.
*/eventTransfer(addressindexedfrom, addressindexed to, uint256indexed tokenId);
/**
* @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
*/eventApproval(addressindexed owner, addressindexed approved, uint256indexed tokenId);
/**
* @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
*/eventApprovalForAll(addressindexed owner, addressindexed operator, bool approved);
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/functionbalanceOf(address owner) externalviewreturns (uint256 balance);
/**
* @dev Returns the owner of the `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functionownerOf(uint256 tokenId) externalviewreturns (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.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytescalldata data
) external;
/**
* @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 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.
*/functionsafeTransferFrom(addressfrom,
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 ERC721
* 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.
*/functiontransferFrom(addressfrom,
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.
*/functionapprove(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.
*/functionsetApprovalForAll(address operator, bool _approved) external;
/**
* @dev Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functiongetApproved(uint256 tokenId) externalviewreturns (address operator);
/**
* @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/functionisApprovedForAll(address owner, address operator) externalviewreturns (bool);
}
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC721/IERC721Receiver.sol)pragmasolidity ^0.8.0;/**
* @title ERC721 token receiver interface
* @dev Interface for any contract that wants to support safeTransfers
* from ERC721 asset contracts.
*/interfaceIERC721Receiver{
/**
* @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`.
*/functiononERC721Received(address operator,
addressfrom,
uint256 tokenId,
bytescalldata data
) externalreturns (bytes4);
}
Contract Source Code
File 16 of 18: Math.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)pragmasolidity ^0.8.0;/**
* @dev Standard math utilities missing in the Solidity language.
*/libraryMath{
enumRounding {
Down, // Toward negative infinity
Up, // Toward infinity
Zero // Toward zero
}
/**
* @dev Returns the largest of two numbers.
*/functionmax(uint256 a, uint256 b) internalpurereturns (uint256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/functionmin(uint256 a, uint256 b) internalpurereturns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/functionaverage(uint256 a, uint256 b) internalpurereturns (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 up instead
* of rounding down.
*/functionceilDiv(uint256 a, uint256 b) internalpurereturns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.return a ==0 ? 0 : (a -1) / b +1;
}
/**
* @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
* @dev 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.
*/functionmulDiv(uint256 x,
uint256 y,
uint256 denominator
) internalpurereturns (uint256 result) {
unchecked {
// 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use// use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256// variables such that product = prod1 * 2^256 + prod0.uint256 prod0; // Least significant 256 bits of the productuint256 prod1; // Most significant 256 bits of the productassembly {
let mm :=mulmod(x, y, not(0))
prod0 :=mul(x, y)
prod1 :=sub(sub(mm, prod0), lt(mm, prod0))
}
// Handle non-overflow cases, 256 by 256 division.if (prod1 ==0) {
return prod0 / denominator;
}
// Make sure the result is less than 2^256. Also prevents denominator == 0.require(denominator > prod1);
///////////////////////////////////////////////// 512 by 256 division.///////////////////////////////////////////////// Make division exact by subtracting the remainder from [prod1 prod0].uint256 remainder;
assembly {
// Compute remainder using mulmod.
remainder :=mulmod(x, y, denominator)
// Subtract 256 bit number from 512 bit number.
prod1 :=sub(prod1, gt(remainder, prod0))
prod0 :=sub(prod0, 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.// Does not overflow because the denominator cannot be zero at this stage in the function.uint256 twos = denominator & (~denominator +1);
assembly {
// Divide denominator by twos.
denominator :=div(denominator, twos)
// Divide [prod1 prod0] by twos.
prod0 :=div(prod0, twos)
// Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
twos :=add(div(sub(0, twos), twos), 1)
}
// Shift in bits from prod1 into prod0.
prod0 |= prod1 * twos;
// Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such// that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for// four bits. That is, denominator * inv = 1 mod 2^4.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 2^8
inverse *=2- denominator * inverse; // inverse mod 2^16
inverse *=2- denominator * inverse; // inverse mod 2^32
inverse *=2- denominator * inverse; // inverse mod 2^64
inverse *=2- denominator * inverse; // inverse mod 2^128
inverse *=2- denominator * inverse; // inverse mod 2^256// 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 2^256. Since the preconditions guarantee that the outcome is// less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1// is no longer required.
result = prod0 * inverse;
return result;
}
}
/**
* @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
*/functionmulDiv(uint256 x,
uint256 y,
uint256 denominator,
Rounding rounding
) internalpurereturns (uint256) {
uint256 result = mulDiv(x, y, denominator);
if (rounding == Rounding.Up &&mulmod(x, y, denominator) >0) {
result +=1;
}
return result;
}
/**
* @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
*
* Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
*/functionsqrt(uint256 a) internalpurereturns (uint256) {
if (a ==0) {
return0;
}
// For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.//// We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have// `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.//// This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`// → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`// → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`//// Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.uint256 result =1<< (log2(a) >>1);
// At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,// since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at// every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision// into the expected uint128 result.unchecked {
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
result = (result + a / result) >>1;
return min(result, a / result);
}
}
/**
* @notice Calculates sqrt(a), following the selected rounding direction.
*/functionsqrt(uint256 a, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result = sqrt(a);
return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
}
}
/**
* @dev Return the log in base 2, rounded down, of a positive value.
* Returns 0 if given 0.
*/functionlog2(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >>128>0) {
value >>=128;
result +=128;
}
if (value >>64>0) {
value >>=64;
result +=64;
}
if (value >>32>0) {
value >>=32;
result +=32;
}
if (value >>16>0) {
value >>=16;
result +=16;
}
if (value >>8>0) {
value >>=8;
result +=8;
}
if (value >>4>0) {
value >>=4;
result +=4;
}
if (value >>2>0) {
value >>=2;
result +=2;
}
if (value >>1>0) {
result +=1;
}
}
return result;
}
/**
* @dev Return the log in base 2, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/functionlog2(uint256 value, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result =log2(value);
return result + (rounding == Rounding.Up &&1<< result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 10, rounded down, of a positive value.
* Returns 0 if given 0.
*/functionlog10(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >=10**64) {
value /=10**64;
result +=64;
}
if (value >=10**32) {
value /=10**32;
result +=32;
}
if (value >=10**16) {
value /=10**16;
result +=16;
}
if (value >=10**8) {
value /=10**8;
result +=8;
}
if (value >=10**4) {
value /=10**4;
result +=4;
}
if (value >=10**2) {
value /=10**2;
result +=2;
}
if (value >=10**1) {
result +=1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/functionlog10(uint256 value, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result = log10(value);
return result + (rounding == Rounding.Up &&10**result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 256, rounded down, of a positive value.
* Returns 0 if given 0.
*
* Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
*/functionlog256(uint256 value) internalpurereturns (uint256) {
uint256 result =0;
unchecked {
if (value >>128>0) {
value >>=128;
result +=16;
}
if (value >>64>0) {
value >>=64;
result +=8;
}
if (value >>32>0) {
value >>=32;
result +=4;
}
if (value >>16>0) {
value >>=16;
result +=2;
}
if (value >>8>0) {
result +=1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/functionlog256(uint256 value, Rounding rounding) internalpurereturns (uint256) {
unchecked {
uint256 result = log256(value);
return result + (rounding == Rounding.Up &&1<< (result *8) < value ? 1 : 0);
}
}
}
Contract Source Code
File 17 of 18: Ownable.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)pragmasolidity ^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.
*/abstractcontractOwnableisContext{
addressprivate _owner;
eventOwnershipTransferred(addressindexed previousOwner, addressindexed 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.
*/modifieronlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/functionowner() publicviewvirtualreturns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/function_checkOwner() internalviewvirtual{
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.
*/functionrenounceOwnership() publicvirtualonlyOwner{
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/functiontransferOwnership(address newOwner) publicvirtualonlyOwner{
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) internalvirtual{
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
Contract Source Code
File 18 of 18: Strings.sol
// SPDX-License-Identifier: MIT// OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)pragmasolidity ^0.8.0;import"./math/Math.sol";
/**
* @dev String operations.
*/libraryStrings{
bytes16privateconstant _SYMBOLS ="0123456789abcdef";
uint8privateconstant _ADDRESS_LENGTH =20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/functiontoString(uint256 value) internalpurereturns (stringmemory) {
unchecked {
uint256 length = Math.log10(value) +1;
stringmemory buffer =newstring(length);
uint256 ptr;
/// @solidity memory-safe-assemblyassembly {
ptr :=add(buffer, add(32, length))
}
while (true) {
ptr--;
/// @solidity memory-safe-assemblyassembly {
mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
}
value /=10;
if (value ==0) break;
}
return buffer;
}
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/functiontoHexString(uint256 value) internalpurereturns (stringmemory) {
unchecked {
return toHexString(value, Math.log256(value) +1);
}
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/functiontoHexString(uint256 value, uint256 length) internalpurereturns (stringmemory) {
bytesmemory buffer =newbytes(2* length +2);
buffer[0] ="0";
buffer[1] ="x";
for (uint256 i =2* length +1; i >1; --i) {
buffer[i] = _SYMBOLS[value &0xf];
value >>=4;
}
require(value ==0, "Strings: hex length insufficient");
returnstring(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/functiontoHexString(address addr) internalpurereturns (stringmemory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
}