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Metadatos del Contrato
Compilador
0.8.7+commit.e28d00a7
Idioma
Solidity
Código Fuente del Contrato
Archivo 1 de 18: Address.sol
// SPDX-License-Identifier: MITpragmasolidity ^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
* ====
*/functionisContract(address account) internalviewreturns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in// construction, since the code is only stored at the end of the// constructor execution.uint256 size;
assembly {
size :=extcodesize(account)
}
return size >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 functionCall(target, data, "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"
);
require(isContract(target), "Address: call to non-contract");
(bool success, bytesmemory returndata) = target.call{value: value}(
data
);
return verifyCallResult(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) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytesmemory returndata) = target.staticcall(data);
return verifyCallResult(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) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytesmemory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/functionverifyCallResult(bool success,
bytesmemory returndata,
stringmemory errorMessage
) internalpurereturns (bytesmemory) {
if (success) {
return returndata;
} else {
// 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 assemblyassembly {
let returndata_size :=mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
Código Fuente del Contrato
Archivo 2 de 18: ContentMixin.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;abstractcontractContextMixin{
functionmsgSender() internalviewreturns (addresspayable sender) {
if (msg.sender==address(this)) {
bytesmemory array =msg.data;
uint256 index =msg.data.length;
assembly {
// Load the 32 bytes word from memory with the address on the lower 20 bytes, and mask those.
sender :=and(
mload(add(array, index)),
0xffffffffffffffffffffffffffffffffffffffff
)
}
} else {
sender =payable(msg.sender);
}
return sender;
}
}
Código Fuente del Contrato
Archivo 3 de 18: Context.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;/**
* @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;
}
}
Código Fuente del Contrato
Archivo 4 de 18: EIP712Base.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import {Initializable} from"./Initializable.sol";
contractEIP712BaseisInitializable{
structEIP712Domain {
string name;
string version;
address verifyingContract;
bytes32 salt;
}
stringpublicconstant ERC712_VERSION ="1";
bytes32internalconstant EIP712_DOMAIN_TYPEHASH =keccak256(
bytes(
"EIP712Domain(string name,string version,address verifyingContract,bytes32 salt)"
)
);
bytes32internal domainSeperator;
// supposed to be called once while initializing.// one of the contracts that inherits this contract follows proxy pattern// so it is not possible to do this in a constructorfunction_initializeEIP712(stringmemory name) internalinitializer{
_setDomainSeperator(name);
}
function_setDomainSeperator(stringmemory name) internal{
domainSeperator =keccak256(
abi.encode(
EIP712_DOMAIN_TYPEHASH,
keccak256(bytes(name)),
keccak256(bytes(ERC712_VERSION)),
address(this),
bytes32(getChainId())
)
);
}
functiongetDomainSeperator() publicviewreturns (bytes32) {
return domainSeperator;
}
functiongetChainId() publicviewreturns (uint256) {
uint256 id;
assembly {
id :=chainid()
}
return id;
}
/**
* Accept message hash and returns hash message in EIP712 compatible form
* So that it can be used to recover signer from signature signed using EIP712 formatted data
* https://eips.ethereum.org/EIPS/eip-712
* "\\x19" makes the encoding deterministic
* "\\x01" is the version byte to make it compatible to EIP-191
*/functiontoTypedMessageHash(bytes32 messageHash)
internalviewreturns (bytes32)
{
returnkeccak256(
abi.encodePacked("\x19\x01", getDomainSeperator(), messageHash)
);
}
}
Código Fuente del Contrato
Archivo 5 de 18: ERC165.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;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;
}
}
Código Fuente del Contrato
Archivo 6 de 18: ERC721.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import"./IERC721.sol";
import"./IERC721Receiver.sol";
import"./IERC721Metadata.sol";
import"./Address.sol";
import"./Context.sol";
import"./Strings.sol";
import"./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: balance query for the zero address"
);
return _balances[owner];
}
/**
* @dev See {IERC721-ownerOf}.
*/functionownerOf(uint256 tokenId)
publicviewvirtualoverridereturns (address)
{
address owner = _owners[tokenId];
require(
owner !=address(0),
"ERC721: owner query for nonexistent token"
);
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)
{
require(
_exists(tokenId),
"ERC721Metadata: URI query for nonexistent token"
);
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 overriden 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 owner nor approved for all"
);
_approve(to, tokenId);
}
/**
* @dev See {IERC721-getApproved}.
*/functiongetApproved(uint256 tokenId)
publicviewvirtualoverridereturns (address)
{
require(
_exists(tokenId),
"ERC721: approved query for nonexistent token"
);
return _tokenApprovals[tokenId];
}
/**
* @dev See {IERC721-setApprovalForAll}.
*/functionsetApprovalForAll(address operator, bool approved)
publicvirtualoverride{
require(operator != _msgSender(), "ERC721: approve to caller");
_operatorApprovals[_msgSender()][operator] = approved;
emit ApprovalForAll(_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: transfer caller is not owner nor 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: transfer caller is not owner nor 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 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 _owners[tokenId] !=address(0);
}
/**
* @dev Returns whether `spender` is allowed to manage `tokenId`.
*
* Requirements:
*
* - `tokenId` must exist.
*/function_isApprovedOrOwner(address spender, uint256 tokenId)
internalviewvirtualreturns (bool)
{
require(
_exists(tokenId),
"ERC721: operator query for nonexistent token"
);
address owner = ERC721.ownerOf(tokenId);
return (spender == owner ||
getApproved(tokenId) == spender ||
isApprovedForAll(owner, 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);
_balances[to] +=1;
_owners[tokenId] = to;
emit Transfer(address(0), to, tokenId);
}
/**
* @dev Destroys `tokenId`.
* The approval is cleared when the token is burned.
*
* Requirements:
*
* - `tokenId` must exist.
*
* Emits a {Transfer} event.
*/function_burn(uint256 tokenId) internalvirtual{
address owner = ERC721.ownerOf(tokenId);
_beforeTokenTransfer(owner, address(0), tokenId);
// Clear approvals
_approve(address(0), tokenId);
_balances[owner] -=1;
delete _owners[tokenId];
emit Transfer(owner, address(0), tokenId);
}
/**
* @dev Transfers `tokenId` from `from` to `to`.
* As opposed to {transferFrom}, this imposes no restrictions on msg.sender.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - `tokenId` token must be owned by `from`.
*
* Emits a {Transfer} event.
*/function_transfer(addressfrom,
address to,
uint256 tokenId
) internalvirtual{
require(
ERC721.ownerOf(tokenId) ==from,
"ERC721: transfer of token that is not own"
);
require(to !=address(0), "ERC721: transfer to the zero address");
_beforeTokenTransfer(from, to, tokenId);
// Clear approvals from the previous owner
_approve(address(0), tokenId);
_balances[from] -=1;
_balances[to] +=1;
_owners[tokenId] = to;
emit Transfer(from, to, tokenId);
}
/**
* @dev Approve `to` to operate on `tokenId`
*
* Emits a {Approval} event.
*/function_approve(address to, uint256 tokenId) internalvirtual{
_tokenApprovals[tokenId] = to;
emit Approval(ERC721.ownerOf(tokenId), to, tokenId);
}
/**
* @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 {
assembly {
revert(add(32, reason), mload(reason))
}
}
}
} else {
returntrue;
}
}
/**
* @dev Hook that is called before any token transfer. This includes minting
* and burning.
*
* 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, ``from``'s `tokenId` will be burned.
* - `from` and `to` are never both zero.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256 tokenId
) internalvirtual{}
}
Código Fuente del Contrato
Archivo 7 de 18: ERC721Enumerable.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import"./ERC721.sol";
import"./IERC721Enumerable.sol";
/**
* @dev This implements an optional extension of {ERC721} defined in the EIP that adds
* enumerability of all the token ids in the contract as well as all token ids owned by each
* account.
*/abstractcontractERC721EnumerableisERC721, IERC721Enumerable{
// Mapping from owner to list of owned token IDsmapping(address=>mapping(uint256=>uint256)) private _ownedTokens;
// Mapping from token ID to index of the owner tokens listmapping(uint256=>uint256) private _ownedTokensIndex;
// Array with all token ids, used for enumerationuint256[] private _allTokens;
// Mapping from token id to position in the allTokens arraymapping(uint256=>uint256) private _allTokensIndex;
/**
* @dev See {IERC165-supportsInterface}.
*/functionsupportsInterface(bytes4 interfaceId)
publicviewvirtualoverride(IERC165, ERC721)
returns (bool)
{
return
interfaceId ==type(IERC721Enumerable).interfaceId||super.supportsInterface(interfaceId);
}
/**
* @dev See {IERC721Enumerable-tokenOfOwnerByIndex}.
*/functiontokenOfOwnerByIndex(address owner, uint256 index)
publicviewvirtualoverridereturns (uint256)
{
require(
index < ERC721.balanceOf(owner),
"ERC721Enumerable: owner index out of bounds"
);
return _ownedTokens[owner][index];
}
/**
* @dev See {IERC721Enumerable-totalSupply}.
*/functiontotalSupply() publicviewvirtualoverridereturns (uint256) {
return _allTokens.length;
}
/**
* @dev See {IERC721Enumerable-tokenByIndex}.
*/functiontokenByIndex(uint256 index)
publicviewvirtualoverridereturns (uint256)
{
require(
index < ERC721Enumerable.totalSupply(),
"ERC721Enumerable: global index out of bounds"
);
return _allTokens[index];
}
/**
* @dev Hook that is called before any token transfer. This includes minting
* and burning.
*
* 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, ``from``'s `tokenId` will be burned.
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
*
* To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
*/function_beforeTokenTransfer(addressfrom,
address to,
uint256 tokenId
) internalvirtualoverride{
super._beforeTokenTransfer(from, to, tokenId);
if (from==address(0)) {
_addTokenToAllTokensEnumeration(tokenId);
} elseif (from!= to) {
_removeTokenFromOwnerEnumeration(from, tokenId);
}
if (to ==address(0)) {
_removeTokenFromAllTokensEnumeration(tokenId);
} elseif (to !=from) {
_addTokenToOwnerEnumeration(to, tokenId);
}
}
/**
* @dev Private function to add a token to this extension's ownership-tracking data structures.
* @param to address representing the new owner of the given token ID
* @param tokenId uint256 ID of the token to be added to the tokens list of the given address
*/function_addTokenToOwnerEnumeration(address to, uint256 tokenId) private{
uint256 length = ERC721.balanceOf(to);
_ownedTokens[to][length] = tokenId;
_ownedTokensIndex[tokenId] = length;
}
/**
* @dev Private function to add a token to this extension's token tracking data structures.
* @param tokenId uint256 ID of the token to be added to the tokens list
*/function_addTokenToAllTokensEnumeration(uint256 tokenId) private{
_allTokensIndex[tokenId] = _allTokens.length;
_allTokens.push(tokenId);
}
/**
* @dev Private function to remove a token from this extension's ownership-tracking data structures. Note that
* while the token is not assigned a new owner, the `_ownedTokensIndex` mapping is _not_ updated: this allows for
* gas optimizations e.g. when performing a transfer operation (avoiding double writes).
* This has O(1) time complexity, but alters the order of the _ownedTokens array.
* @param from address representing the previous owner of the given token ID
* @param tokenId uint256 ID of the token to be removed from the tokens list of the given address
*/function_removeTokenFromOwnerEnumeration(addressfrom, uint256 tokenId)
private{
// To prevent a gap in from's tokens array, we store the last token in the index of the token to delete, and// then delete the last slot (swap and pop).uint256 lastTokenIndex = ERC721.balanceOf(from) -1;
uint256 tokenIndex = _ownedTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessaryif (tokenIndex != lastTokenIndex) {
uint256 lastTokenId = _ownedTokens[from][lastTokenIndex];
_ownedTokens[from][tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_ownedTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index
}
// This also deletes the contents at the last position of the arraydelete _ownedTokensIndex[tokenId];
delete _ownedTokens[from][lastTokenIndex];
}
/**
* @dev Private function to remove a token from this extension's token tracking data structures.
* This has O(1) time complexity, but alters the order of the _allTokens array.
* @param tokenId uint256 ID of the token to be removed from the tokens list
*/function_removeTokenFromAllTokensEnumeration(uint256 tokenId) private{
// To prevent a gap in the tokens array, we store the last token in the index of the token to delete, and// then delete the last slot (swap and pop).uint256 lastTokenIndex = _allTokens.length-1;
uint256 tokenIndex = _allTokensIndex[tokenId];
// When the token to delete is the last token, the swap operation is unnecessary. However, since this occurs so// rarely (when the last minted token is burnt) that we still do the swap here to avoid the gas cost of adding// an 'if' statement (like in _removeTokenFromOwnerEnumeration)uint256 lastTokenId = _allTokens[lastTokenIndex];
_allTokens[tokenIndex] = lastTokenId; // Move the last token to the slot of the to-delete token
_allTokensIndex[lastTokenId] = tokenIndex; // Update the moved token's index// This also deletes the contents at the last position of the arraydelete _allTokensIndex[tokenId];
_allTokens.pop();
}
}
Código Fuente del Contrato
Archivo 8 de 18: FarmerApes.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import"./ERC721.sol";
import"./ERC721Enumerable.sol";
import"./Ownable.sol";
import"./SafeMath.sol";
import"./Strings.sol";
import"./ContentMixin.sol";
import"./NativeMetaTransaction.sol";
interfaceIERC721Contract{
/**
* @dev Returns the number of tokens in ``owner``'s account.
*/functionbalanceOf(address owner) externalviewreturns (uint256 balance);
}
interfaceYieldToken{
functionupdateRewardOnMint(address _user) external;
functionupdateReward(address _from, address _to) external;
functionclaimReward(address _to) external;
}
/**
* @title FarmerApes
*/contractFarmerApesisContextMixin,
ERC721Enumerable,
NativeMetaTransaction,
Ownable{
usingSafeMathforuint256;
stringpublic baseTokenURI;
uint256private _currentTokenId;
uint256publicconstant MAX_SUPPLY =8888;
uint8publicconstant MAX_MINT_LIMIT =10;
uint256privateconstant GIFT_COUNT =88;
uint256public mintBeforeReserve;
uint256public totalAirdropNum;
addresspublic hawaiiApe;
uint256public totalReserved;
uint256public presalePrice =.0588ether;
uint256public publicSalePrice =.06ether;
uint256public presaleTime =1639584000;
uint256public publicSaleTime =1639670415;
boolpublic ApprovedAsHolder =true;
boolpublic inPublic;
mapping(address=>bool) public whitelisters;
mapping(address=>bool) public presaleStatus;
mapping(address=>uint8) public reserved;
mapping(address=>uint8) public claimed;
mapping(address=>uint8) public airdropNum;
mapping(uint256=> RarityType) private apeType;
mapping(address=>uint256) private yield;
enumRarityType {
Null,
Common,
Rare,
SuperRare,
Epic,
Lengendary
}
YieldToken public yieldToken;
IERC721Contract public BAYC;
IERC721Contract public MAYC;
eventValueChanged(stringindexed fieldName, uint256 newValue);
eventLuckyApe(uint256indexed tokenId, addressindexed luckyAddress);
eventLegendaryDrop(uint256indexed tokenId, addressindexed luckyAddress);
/**
* @dev Throws if called by any account that's not whitelisted.
*/modifieronlyWhitelisted() {
require(
checkWhiteList(msg.sender),
"FarmerApes: Oops, sorry you're not whitelisted."
);
_;
}
constructor(stringmemory _name,
stringmemory _symbol,
stringmemory _uri,
address _BAYC,
address _MAYC
) ERC721(_name, _symbol) {
baseTokenURI = _uri;
_initializeEIP712(_name);
BAYC = IERC721Contract(_BAYC);
MAYC = IERC721Contract(_MAYC);
}
/**
* @dev Check user is on the whitelist or not.
* @param user msg.sender
*/functioncheckWhiteList(address user) publicviewreturns (bool) {
if (ApprovedAsHolder) {
return
whitelisters[user] ||
BAYC.balanceOf(user) >0||
MAYC.balanceOf(user) >0;
} else {
return whitelisters[user];
}
}
functionsetPresalePrice(uint256 newPrice) externalonlyOwner{
presalePrice = newPrice;
emit ValueChanged("presalePrice", newPrice);
}
functionsetPublicPrice(uint256 newPrice) externalonlyOwner{
publicSalePrice = newPrice;
emit ValueChanged("publicSalePrice", newPrice);
}
/**
* @dev Mint to msg.sender. Only whitelisted users can participate
*/functionpresale() externalpayableonlyWhitelisted{
require(
block.timestamp>= presaleTime &&block.timestamp< presaleTime +1days,
"FarmerApes: Presale has yet to be started."
);
require(msg.value== presalePrice, "FarmerApes: Invalid value.");
require(
!presaleStatus[msg.sender],
"FarmerApe: You had already participated in presale."
);
require(
totalSupply() +1<= MAX_SUPPLY - GIFT_COUNT,
"FarmerApes: Sorry, we are sold out."
);
_mintMany(1);
presaleStatus[msg.sender] =true;
}
/**
* @dev Reserve for the purchase. Each address is allowed to purchase up to 10 FarmerApes.
* @param _num Quantity to purchase
*/functionreserve(uint8 _num) externalpayable{
require(
block.timestamp>= publicSaleTime &&block.timestamp<= publicSaleTime +7days,
"FarmerApes: Public sale has yet to be started."
);
if (mintBeforeReserve ==0) {
mintBeforeReserve = totalSupply();
}
require(
(_num + reserved[msg.sender] + claimed[msg.sender]) <=
MAX_MINT_LIMIT,
"FarmerApes: Each address is allowed to purchase up to 10 FarmerApes."
);
require(
mintBeforeReserve +uint256(_num) <=
MAX_SUPPLY - totalReserved - (GIFT_COUNT - totalAirdropNum),
"FarmerApes: Sorry, we are sold out."
);
require(
msg.value==uint256(_num) * publicSalePrice,
"FarmerApes: Invalid value."
);
reserved[msg.sender] += _num;
totalReserved +=uint256(_num);
}
/**
* @dev FarmerApes can only be claimed after your reservation.
*/functionclaim() external{
require(
block.timestamp>= publicSaleTime &&block.timestamp<= publicSaleTime +7days,
"FarmerApes: You have missed the time window. Your Farmer Ape has escaped."
);
_mintMany(reserved[msg.sender]);
claimed[msg.sender] += reserved[msg.sender];
reserved[msg.sender] =0;
}
/**
* @dev set the presale and public sale time only by Admin
*/functionupdateTime(uint256 _preSaleTime, uint256 _publicSaleTime)
externalonlyOwner{
require(
_publicSaleTime > _preSaleTime,
"FarmerApes: Invalid time set."
);
presaleTime = _preSaleTime;
publicSaleTime = _publicSaleTime;
emit ValueChanged("presaleTime", _preSaleTime);
emit ValueChanged("publicSaleTime", _publicSaleTime);
}
functionsetAPCToken(address _APC) externalonlyOwner{
yieldToken = YieldToken(_APC);
}
functionsetInPublic(bool _inPublic) externalonlyOwner{
inPublic = _inPublic;
}
functionsetIfApprovedAsHolder(bool _ApprovedAsHolder) externalonlyOwner{
ApprovedAsHolder = _ApprovedAsHolder;
}
/**
* @dev Mint and airdrop apes to several addresses directly.
* @param _recipients addressses of the future holder of Farmer Apes.
* @param rTypes rarity types of the future holder of Farmer Apes.
*/functionmintTo(address[] memory _recipients, uint8[] memory rTypes)
externalonlyOwner{
for (uint256 i =0; i < _recipients.length; i++) {
uint256 newTokenId = _getNextTokenId();
_mintTo(_recipients[i], newTokenId, rTypes[i]);
checkRoadmap(newTokenId);
_incrementTokenId();
}
require(
GIFT_COUNT - totalAirdropNum >= _recipients.length,
"We've reached the maximum of airdrop limits."
);
totalAirdropNum += _recipients.length;
}
function_mintTo(address to,
uint256 tokenId,
uint8 rType
) internal{
yieldToken.updateRewardOnMint(to);
if (rType ==0) {
apeType[tokenId] = randomRarity();
} else {
apeType[tokenId] = RarityType(rType);
}
super._mint(to, tokenId);
yield[to] += getApeYield(tokenId);
}
functionrandomRarity() internalviewreturns (RarityType rtype) {
uint256 randomNumber = (random(_currentTokenId) %10000) +1;
if (randomNumber <=8000) {
return RarityType.Common;
} elseif (randomNumber <=9387) {
return RarityType.Rare;
} elseif (randomNumber <=9887) {
return RarityType.SuperRare;
} elseif (randomNumber <=9987) {
return RarityType.Epic;
} else {
return RarityType.Lengendary;
}
}
/**
* @dev Airdrop apes to several addresses.
* @param _recipients Holders are able to mint Farmer Apes for free.
*/functionairdrop(address[] memory _recipients, uint8[] memory _amounts)
externalonlyOwner{
uint256 _airdropNum;
require(
block.timestamp>= publicSaleTime,
"FarmerApes: Public sale has yet to be started."
);
for (uint256 i =0; i < _recipients.length; i++) {
_airdropNum += _amounts[i];
airdropNum[_recipients[i]] = _amounts[i];
}
require(
GIFT_COUNT - totalAirdropNum >= _airdropNum,
"We've reached the maximum of airdrop limits."
);
totalAirdropNum += _airdropNum;
}
functiongetAirdrop() external{
require(
airdropNum[msg.sender] >0&&block.timestamp<= publicSaleTime +7days,
"FarmerApes: You have missed the time window. Your Farmer Ape has escaped."
);
_mintMany(airdropNum[msg.sender]);
airdropNum[msg.sender] =0;
}
functioncheckRoadmap(uint256 newTokenId) internal{
if (newTokenId %888==0) {
uint256 apeId = newTokenId - (random(newTokenId) %888);
address luckyAddress = ownerOf(apeId);
payable(luckyAddress).transfer(.888ether);
emit LuckyApe(apeId, luckyAddress);
}
// For every 4444 sales, a legendary NFT will be airdropped to a lucky ape holder.if (newTokenId ==4444|| newTokenId == MAX_SUPPLY +2- GIFT_COUNT) {
uint256 apeId = newTokenId - (random(newTokenId) %4444);
address luckyAddress = ownerOf(apeId);
emit LegendaryDrop(apeId, luckyAddress);
}
}
/**
* @dev Mint Farmer Apes.
*/function_mintMany(uint8 _num) private{
for (uint8 i =0; i < _num; i++) {
uint256 newTokenId = _getNextTokenId();
_mint(msg.sender, newTokenId);
_incrementTokenId();
checkRoadmap(newTokenId);
}
}
/**
* @dev calculates the next token ID based on value of _currentTokenId
* @return uint256 for the next token ID
*/function_getNextTokenId() privateviewreturns (uint256) {
return _currentTokenId.add(1);
}
/**
* @dev Once we sell out, a lucky Hawaii ape holder with at least 2 Farmer Apes will be selected to jump to a paid trip.
*/function_randomTripApeAddress(uint256 seed) internalreturns (address) {
uint256 apeId = (random(seed) % _currentTokenId) +1;
address apeAddress = ownerOf(apeId);
if (balanceOf(apeAddress) >=2) {
return apeAddress;
}
return _randomTripApeAddress(random(seed));
}
/**
* @dev Get the lucky ape for a paid trip to Hawaii
* @return address
*/functionrandomTripApeAddress() externalonlyOwnerreturns (address) {
require(hawaiiApe ==address(0), "The ape has already selected.");
hawaiiApe = _randomTripApeAddress(_currentTokenId);
return hawaiiApe;
}
/**
* generates a pseudorandom number
* @param seed a value ensure different outcomes for different sources in the same block
* @return a pseudorandom value
*/functionrandom(uint256 seed) internalviewreturns (uint256) {
returnuint256(
keccak256(
abi.encodePacked(
tx.origin,
blockhash(block.number-1),
block.timestamp,
seed
)
)
);
}
/**
* @dev increments the value of _currentTokenId
*/function_incrementTokenId() private{
require(_currentTokenId < MAX_SUPPLY);
_currentTokenId++;
}
/**
* @dev change the baseTokenURI only by Admin
*/functionsetBaseUri(stringmemory _uri) externalonlyOwner{
baseTokenURI = _uri;
}
functiontokenURI(uint256 _tokenId)
publicviewoverridereturns (stringmemory)
{
returnstring(abi.encodePacked(baseTokenURI, Strings.toString(_tokenId)));
}
function_msgSender() internalviewoverridereturns (address sender) {
return ContextMixin.msgSender();
}
functionwithdraw() externalonlyOwner{
uint256 balance =address(this).balance;
payable(address(0xa297c335fF5De7b2a8f2F95283456FDA26ddbfE4)).transfer(
(balance *3) /100
);
payable(address(0x25f9454ABf96C656A151D85cD74EFD008838Aa54)).transfer(
(balance *8) /1000
);
payable(address(0xa9b16C30a17D91a91746b072D7700971651e8d7A)).transfer(
(balance *3) /100
);
payable(owner()).transfer(address(this).balance);
}
receive() externalpayable{}
/**
* @dev Set whitelist
* @param whitelistAddresses Whitelist addresses
*/functionaddWhitelisters(address[] calldata whitelistAddresses)
externalonlyOwner{
for (uint256 i; i < whitelistAddresses.length; i++) {
whitelisters[whitelistAddresses[i]] =true;
}
}
/**
* @dev To know each Token's type and daily Yield.
* @param tokenId token id
*/functiongetApeTypeAndYield(uint256 tokenId)
externalviewreturns (RarityType rType, uint256 apeYield)
{
if (inPublic) {
rType = apeType[tokenId];
apeYield = getApeYield(tokenId);
} else {
rType = RarityType.Null;
apeYield =0;
}
}
/**
* @dev To know each Token's daily Yield.
* @param tokenId token id
*/functiongetApeYield(uint256 tokenId)
internalviewreturns (uint256 apeYield)
{
if (apeType[tokenId] == RarityType.Common) {
return6;
}
if (apeType[tokenId] == RarityType.Rare) {
return7;
}
if (apeType[tokenId] == RarityType.SuperRare) {
return8;
}
if (apeType[tokenId] == RarityType.Epic) {
return9;
}
if (apeType[tokenId] == RarityType.Lengendary) {
return15;
}
}
/**
* @dev To know each address's total daily Yield.
* @param user address
*/functiongetUserYield(address user) externalviewreturns (uint256) {
if (!inPublic) return0;
return yield[user] *1e18;
}
/**
* @dev To claim your total reward.
*/functionclaimReward() external{
yieldToken.updateReward(msg.sender, address(0));
yieldToken.claimReward(msg.sender);
}
function_mint(address to, uint256 tokenId) internalvirtualoverride{
yieldToken.updateRewardOnMint(to);
apeType[tokenId] = randomRarity();
super._mint(to, tokenId);
yield[to] += getApeYield(tokenId);
}
functiontransferFrom(addressfrom,
address to,
uint256 tokenId
) publicoverride{
yieldToken.updateReward(from, to);
yield[from] -= getApeYield(tokenId);
yield[to] += getApeYield(tokenId);
super.transferFrom(from, to, tokenId);
}
functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId,
bytesmemory _data
) publicoverride{
yieldToken.updateReward(from, to);
yield[from] -= getApeYield(tokenId);
yield[to] += getApeYield(tokenId);
super.safeTransferFrom(from, to, tokenId, _data);
}
}
Código Fuente del Contrato
Archivo 9 de 18: IERC165.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;/**
* @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);
}
Código Fuente del Contrato
Archivo 10 de 18: IERC721.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import"./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`, 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.
*/functionsafeTransferFrom(addressfrom,
address to,
uint256 tokenId
) external;
/**
* @dev Transfers `tokenId` token 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.
*/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 Returns the account approved for `tokenId` token.
*
* Requirements:
*
* - `tokenId` must exist.
*/functiongetApproved(uint256 tokenId)
externalviewreturns (address operator);
/**
* @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 if the `operator` is allowed to manage all of the assets of `owner`.
*
* See {setApprovalForAll}
*/functionisApprovedForAll(address owner, address operator)
externalviewreturns (bool);
/**
* @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;
}
Código Fuente del Contrato
Archivo 11 de 18: IERC721Enumerable.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import"./IERC721.sol";
/**
* @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
* @dev See https://eips.ethereum.org/EIPS/eip-721
*/interfaceIERC721EnumerableisIERC721{
/**
* @dev Returns the total amount of tokens stored by the contract.
*/functiontotalSupply() externalviewreturns (uint256);
/**
* @dev Returns a token ID owned by `owner` at a given `index` of its token list.
* Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
*/functiontokenOfOwnerByIndex(address owner, uint256 index)
externalviewreturns (uint256 tokenId);
/**
* @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
* Use along with {totalSupply} to enumerate all tokens.
*/functiontokenByIndex(uint256 index) externalviewreturns (uint256);
}
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;/**
* @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 `IERC721.onERC721Received.selector`.
*/functiononERC721Received(address operator,
addressfrom,
uint256 tokenId,
bytescalldata data
) externalreturns (bytes4);
}
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import {SafeMath} from"./SafeMath.sol";
import {EIP712Base} from"./EIP712Base.sol";
contractNativeMetaTransactionisEIP712Base{
usingSafeMathforuint256;
bytes32privateconstant META_TRANSACTION_TYPEHASH =keccak256(
bytes(
"MetaTransaction(uint256 nonce,address from,bytes functionSignature)"
)
);
eventMetaTransactionExecuted(address userAddress,
addresspayable relayerAddress,
bytes functionSignature
);
mapping(address=>uint256) nonces;
/*
* Meta transaction structure.
* No point of including value field here as if user is doing value transfer then he has the funds to pay for gas
* He should call the desired function directly in that case.
*/structMetaTransaction {
uint256 nonce;
addressfrom;
bytes functionSignature;
}
functionexecuteMetaTransaction(address userAddress,
bytesmemory functionSignature,
bytes32 sigR,
bytes32 sigS,
uint8 sigV
) publicpayablereturns (bytesmemory) {
MetaTransaction memory metaTx = MetaTransaction({
nonce: nonces[userAddress],
from: userAddress,
functionSignature: functionSignature
});
require(
verify(userAddress, metaTx, sigR, sigS, sigV),
"Signer and signature do not match"
);
// increase nonce for user (to avoid re-use)
nonces[userAddress] = nonces[userAddress].add(1);
emit MetaTransactionExecuted(
userAddress,
payable(msg.sender),
functionSignature
);
// Append userAddress and relayer address at the end to extract it from calling context
(bool success, bytesmemory returnData) =address(this).call(
abi.encodePacked(functionSignature, userAddress)
);
require(success, "Function call not successful");
return returnData;
}
functionhashMetaTransaction(MetaTransaction memory metaTx)
internalpurereturns (bytes32)
{
returnkeccak256(
abi.encode(
META_TRANSACTION_TYPEHASH,
metaTx.nonce,
metaTx.from,
keccak256(metaTx.functionSignature)
)
);
}
functiongetNonce(address user) publicviewreturns (uint256 nonce) {
nonce = nonces[user];
}
functionverify(address signer,
MetaTransaction memory metaTx,
bytes32 sigR,
bytes32 sigS,
uint8 sigV
) internalviewreturns (bool) {
require(signer !=address(0), "NativeMetaTransaction: INVALID_SIGNER");
return
signer ==ecrecover(
toTypedMessageHash(hashMetaTransaction(metaTx)),
sigV,
sigR,
sigS
);
}
}
Código Fuente del Contrato
Archivo 16 de 18: Ownable.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;import"./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() {
_setOwner(_msgSender());
}
/**
* @dev Returns the address of the current owner.
*/functionowner() publicviewvirtualreturns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/modifieronlyOwner() {
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{
_setOwner(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"
);
_setOwner(newOwner);
}
function_setOwner(address newOwner) private{
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
Código Fuente del Contrato
Archivo 17 de 18: SafeMath.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;// CAUTION// This version of SafeMath should only be used with Solidity 0.8 or later,// because it relies on the compiler's built in overflow checks./**
* @dev Wrappers over Solidity's arithmetic operations.
*
* NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
* now has built in overflow checking.
*/librarySafeMath{
/**
* @dev Returns the addition of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/functiontryAdd(uint256 a, uint256 b)
internalpurereturns (bool, uint256)
{
unchecked {
uint256 c = a + b;
if (c < a) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the substraction of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/functiontrySub(uint256 a, uint256 b)
internalpurereturns (bool, uint256)
{
unchecked {
if (b > a) return (false, 0);
return (true, a - b);
}
}
/**
* @dev Returns the multiplication of two unsigned integers, with an overflow flag.
*
* _Available since v3.4._
*/functiontryMul(uint256 a, uint256 b)
internalpurereturns (bool, uint256)
{
unchecked {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the// benefit is lost if 'b' is also tested.// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522if (a ==0) return (true, 0);
uint256 c = a * b;
if (c / a != b) return (false, 0);
return (true, c);
}
}
/**
* @dev Returns the division of two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/functiontryDiv(uint256 a, uint256 b)
internalpurereturns (bool, uint256)
{
unchecked {
if (b ==0) return (false, 0);
return (true, a / b);
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
*
* _Available since v3.4._
*/functiontryMod(uint256 a, uint256 b)
internalpurereturns (bool, uint256)
{
unchecked {
if (b ==0) return (false, 0);
return (true, a % b);
}
}
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
*
* - Addition cannot overflow.
*/functionadd(uint256 a, uint256 b) internalpurereturns (uint256) {
return a + b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/functionsub(uint256 a, uint256 b) internalpurereturns (uint256) {
return a - b;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
*
* - Multiplication cannot overflow.
*/functionmul(uint256 a, uint256 b) internalpurereturns (uint256) {
return a * b;
}
/**
* @dev Returns the integer division of two unsigned integers, reverting on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator.
*
* Requirements:
*
* - The divisor cannot be zero.
*/functiondiv(uint256 a, uint256 b) internalpurereturns (uint256) {
return a / b;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/functionmod(uint256 a, uint256 b) internalpurereturns (uint256) {
return a % b;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting with custom message on
* overflow (when the result is negative).
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {trySub}.
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
*
* - Subtraction cannot overflow.
*/functionsub(uint256 a,
uint256 b,
stringmemory errorMessage
) internalpurereturns (uint256) {
unchecked {
require(b <= a, errorMessage);
return a - b;
}
}
/**
* @dev Returns the integer division of two unsigned integers, reverting with custom message on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/functiondiv(uint256 a,
uint256 b,
stringmemory errorMessage
) internalpurereturns (uint256) {
unchecked {
require(b >0, errorMessage);
return a / b;
}
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* reverting with custom message when dividing by zero.
*
* CAUTION: This function is deprecated because it requires allocating memory for the error
* message unnecessarily. For custom revert reasons use {tryMod}.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
*
* - The divisor cannot be zero.
*/functionmod(uint256 a,
uint256 b,
stringmemory errorMessage
) internalpurereturns (uint256) {
unchecked {
require(b >0, errorMessage);
return a % b;
}
}
}
Código Fuente del Contrato
Archivo 18 de 18: Strings.sol
// SPDX-License-Identifier: MITpragmasolidity ^0.8.1;/**
* @dev String operations.
*/libraryStrings{
bytes16privateconstant _HEX_SYMBOLS ="0123456789abcdef";
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/functiontoString(uint256 value) internalpurereturns (stringmemory) {
// Inspired by OraclizeAPI's implementation - MIT licence// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.solif (value ==0) {
return"0";
}
uint256 temp = value;
uint256 digits;
while (temp !=0) {
digits++;
temp /=10;
}
bytesmemory buffer =newbytes(digits);
while (value !=0) {
digits -=1;
buffer[digits] =bytes1(uint8(48+uint256(value %10)));
value /=10;
}
returnstring(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/functiontoHexString(uint256 value) internalpurereturns (stringmemory) {
if (value ==0) {
return"0x00";
}
uint256 temp = value;
uint256 length =0;
while (temp !=0) {
length++;
temp >>=8;
}
return toHexString(value, length);
}
/**
* @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] = _HEX_SYMBOLS[value &0xf];
value >>=4;
}
require(value ==0, "Strings: hex length insufficient");
returnstring(buffer);
}
}