Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/AccessControl.sol)
pragma solidity ^0.8.20;
import {IAccessControl} from "./IAccessControl.sol";
import {Context} from "../utils/Context.sol";
import {ERC165} from "../utils/introspection/ERC165.sol";
/**
* @dev Contract module that allows children to implement role-based access
* control mechanisms. This is a lightweight version that doesn't allow enumerating role
* members except through off-chain means by accessing the contract event logs. Some
* applications may benefit from on-chain enumerability, for those cases see
* {AccessControlEnumerable}.
*
* Roles are referred to by their `bytes32` identifier. These should be exposed
* in the external API and be unique. The best way to achieve this is by
* using `public constant` hash digests:
*
* ```solidity
* bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
* ```
*
* Roles can be used to represent a set of permissions. To restrict access to a
* function call, use {hasRole}:
*
* ```solidity
* function foo() public {
* require(hasRole(MY_ROLE, msg.sender));
* ...
* }
* ```
*
* Roles can be granted and revoked dynamically via the {grantRole} and
* {revokeRole} functions. Each role has an associated admin role, and only
* accounts that have a role's admin role can call {grantRole} and {revokeRole}.
*
* By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
* that only accounts with this role will be able to grant or revoke other
* roles. More complex role relationships can be created by using
* {_setRoleAdmin}.
*
* WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
* grant and revoke this role. Extra precautions should be taken to secure
* accounts that have been granted it. We recommend using {AccessControlDefaultAdminRules}
* to enforce additional security measures for this role.
*/
abstract contract AccessControl is Context, IAccessControl, ERC165 {
struct RoleData {
mapping(address account => bool) hasRole;
bytes32 adminRole;
}
mapping(bytes32 role => RoleData) private _roles;
bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
/**
* @dev Modifier that checks that an account has a specific role. Reverts
* with an {AccessControlUnauthorizedAccount} error including the required role.
*/
modifier onlyRole(bytes32 role) {
_checkRole(role);
_;
}
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return interfaceId == type(IAccessControl).interfaceId || super.supportsInterface(interfaceId);
}
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) public view virtual returns (bool) {
return _roles[role].hasRole[account];
}
/**
* @dev Reverts with an {AccessControlUnauthorizedAccount} error if `_msgSender()`
* is missing `role`. Overriding this function changes the behavior of the {onlyRole} modifier.
*/
function _checkRole(bytes32 role) internal view virtual {
_checkRole(role, _msgSender());
}
/**
* @dev Reverts with an {AccessControlUnauthorizedAccount} error if `account`
* is missing `role`.
*/
function _checkRole(bytes32 role, address account) internal view virtual {
if (!hasRole(role, account)) {
revert AccessControlUnauthorizedAccount(account, role);
}
}
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) public view virtual returns (bytes32) {
return _roles[role].adminRole;
}
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*
* May emit a {RoleGranted} event.
*/
function grantRole(bytes32 role, address account) public virtual onlyRole(getRoleAdmin(role)) {
_grantRole(role, account);
}
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*
* May emit a {RoleRevoked} event.
*/
function revokeRole(bytes32 role, address account) public virtual onlyRole(getRoleAdmin(role)) {
_revokeRole(role, account);
}
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been revoked `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `callerConfirmation`.
*
* May emit a {RoleRevoked} event.
*/
function renounceRole(bytes32 role, address callerConfirmation) public virtual {
if (callerConfirmation != _msgSender()) {
revert AccessControlBadConfirmation();
}
_revokeRole(role, callerConfirmation);
}
/**
* @dev Sets `adminRole` as ``role``'s admin role.
*
* Emits a {RoleAdminChanged} event.
*/
function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
bytes32 previousAdminRole = getRoleAdmin(role);
_roles[role].adminRole = adminRole;
emit RoleAdminChanged(role, previousAdminRole, adminRole);
}
/**
* @dev Attempts to grant `role` to `account` and returns a boolean indicating if `role` was granted.
*
* Internal function without access restriction.
*
* May emit a {RoleGranted} event.
*/
function _grantRole(bytes32 role, address account) internal virtual returns (bool) {
if (!hasRole(role, account)) {
_roles[role].hasRole[account] = true;
emit RoleGranted(role, account, _msgSender());
return true;
} else {
return false;
}
}
/**
* @dev Attempts to revoke `role` to `account` and returns a boolean indicating if `role` was revoked.
*
* Internal function without access restriction.
*
* May emit a {RoleRevoked} event.
*/
function _revokeRole(bytes32 role, address account) internal virtual returns (bool) {
if (hasRole(role, account)) {
_roles[role].hasRole[account] = false;
emit RoleRevoked(role, account, _msgSender());
return true;
} else {
return false;
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (access/IAccessControl.sol)
pragma solidity ^0.8.20;
/**
* @dev External interface of AccessControl declared to support ERC-165 detection.
*/
interface IAccessControl {
/**
* @dev The `account` is missing a role.
*/
error AccessControlUnauthorizedAccount(address account, bytes32 neededRole);
/**
* @dev The caller of a function is not the expected one.
*
* NOTE: Don't confuse with {AccessControlUnauthorizedAccount}.
*/
error AccessControlBadConfirmation();
/**
* @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
*
* `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
* {RoleAdminChanged} not being emitted signaling this.
*/
event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
/**
* @dev Emitted when `account` is granted `role`.
*
* `sender` is the account that originated the contract call. This account bears the admin role (for the granted role).
* Expected in cases where the role was granted using the internal {AccessControl-_grantRole}.
*/
event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Emitted when `account` is revoked `role`.
*
* `sender` is the account that originated the contract call:
* - if using `revokeRole`, it is the admin role bearer
* - if using `renounceRole`, it is the role bearer (i.e. `account`)
*/
event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
/**
* @dev Returns `true` if `account` has been granted `role`.
*/
function hasRole(bytes32 role, address account) external view returns (bool);
/**
* @dev Returns the admin role that controls `role`. See {grantRole} and
* {revokeRole}.
*
* To change a role's admin, use {AccessControl-_setRoleAdmin}.
*/
function getRoleAdmin(bytes32 role) external view returns (bytes32);
/**
* @dev Grants `role` to `account`.
*
* If `account` had not been already granted `role`, emits a {RoleGranted}
* event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function grantRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from `account`.
*
* If `account` had been granted `role`, emits a {RoleRevoked} event.
*
* Requirements:
*
* - the caller must have ``role``'s admin role.
*/
function revokeRole(bytes32 role, address account) external;
/**
* @dev Revokes `role` from the calling account.
*
* Roles are often managed via {grantRole} and {revokeRole}: this function's
* purpose is to provide a mechanism for accounts to lose their privileges
* if they are compromised (such as when a trusted device is misplaced).
*
* If the calling account had been granted `role`, emits a {RoleRevoked}
* event.
*
* Requirements:
*
* - the caller must be `callerConfirmation`.
*/
function renounceRole(bytes32 role, address callerConfirmation) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
pragma solidity ^0.8.20;
import {Context} from "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* The initial owner is set to the address provided by the deployer. This can
* later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
/**
* @dev The caller account is not authorized to perform an operation.
*/
error OwnableUnauthorizedAccount(address account);
/**
* @dev The owner is not a valid owner account. (eg. `address(0)`)
*/
error OwnableInvalidOwner(address owner);
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the address provided by the deployer as the initial owner.
*/
constructor(address initialOwner) {
if (initialOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(initialOwner);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
if (owner() != _msgSender()) {
revert OwnableUnauthorizedAccount(_msgSender());
}
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
if (newOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (interfaces/draft-IERC6093.sol)
pragma solidity ^0.8.20;
/**
* @dev Standard ERC-20 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-20 tokens.
*/
interface IERC20Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC20InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC20InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
* @param spender Address that may be allowed to operate on tokens without being their owner.
* @param allowance Amount of tokens a `spender` is allowed to operate with.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC20InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `spender` to be approved. Used in approvals.
* @param spender Address that may be allowed to operate on tokens without being their owner.
*/
error ERC20InvalidSpender(address spender);
}
/**
* @dev Standard ERC-721 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-721 tokens.
*/
interface IERC721Errors {
/**
* @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in ERC-20.
* Used in balance queries.
* @param owner Address of the current owner of a token.
*/
error ERC721InvalidOwner(address owner);
/**
* @dev Indicates a `tokenId` whose `owner` is the zero address.
* @param tokenId Identifier number of a token.
*/
error ERC721NonexistentToken(uint256 tokenId);
/**
* @dev Indicates an error related to the ownership over a particular token. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param tokenId Identifier number of a token.
* @param owner Address of the current owner of a token.
*/
error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC721InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC721InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param tokenId Identifier number of a token.
*/
error ERC721InsufficientApproval(address operator, uint256 tokenId);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC721InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC721InvalidOperator(address operator);
}
/**
* @dev Standard ERC-1155 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC-1155 tokens.
*/
interface IERC1155Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
* @param tokenId Identifier number of a token.
*/
error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC1155InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC1155InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param owner Address of the current owner of a token.
*/
error ERC1155MissingApprovalForAll(address operator, address owner);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC1155InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC1155InvalidOperator(address operator);
/**
* @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
* Used in batch transfers.
* @param idsLength Length of the array of token identifiers
* @param valuesLength Length of the array of token amounts
*/
error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.20;
import {IERC20} from "./IERC20.sol";
import {IERC20Metadata} from "./extensions/IERC20Metadata.sol";
import {Context} from "../../utils/Context.sol";
import {IERC20Errors} from "../../interfaces/draft-IERC6093.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
*
* TIP: For a detailed writeup see our guide
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* The default value of {decimals} is 18. To change this, you should override
* this function so it returns a different value.
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC-20
* applications.
*/
abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {
mapping(address account => uint256) private _balances;
mapping(address account => mapping(address spender => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the default value returned by this function, unless
* it's overridden.
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `value`.
*/
function transfer(address to, uint256 value) public virtual returns (bool) {
address owner = _msgSender();
_transfer(owner, to, value);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* NOTE: If `value` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public virtual returns (bool) {
address owner = _msgSender();
_approve(owner, spender, value);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Skips emitting an {Approval} event indicating an allowance update. This is not
* required by the ERC. See {xref-ERC20-_approve-address-address-uint256-bool-}[_approve].
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `value`.
* - the caller must have allowance for ``from``'s tokens of at least
* `value`.
*/
function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, value);
_transfer(from, to, value);
return true;
}
/**
* @dev Moves a `value` amount of tokens from `from` to `to`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* NOTE: This function is not virtual, {_update} should be overridden instead.
*/
function _transfer(address from, address to, uint256 value) internal {
if (from == address(0)) {
revert ERC20InvalidSender(address(0));
}
if (to == address(0)) {
revert ERC20InvalidReceiver(address(0));
}
_update(from, to, value);
}
/**
* @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`
* (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding
* this function.
*
* Emits a {Transfer} event.
*/
function _update(address from, address to, uint256 value) internal virtual {
if (from == address(0)) {
// Overflow check required: The rest of the code assumes that totalSupply never overflows
_totalSupply += value;
} else {
uint256 fromBalance = _balances[from];
if (fromBalance < value) {
revert ERC20InsufficientBalance(from, fromBalance, value);
}
unchecked {
// Overflow not possible: value <= fromBalance <= totalSupply.
_balances[from] = fromBalance - value;
}
}
if (to == address(0)) {
unchecked {
// Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
_totalSupply -= value;
}
} else {
unchecked {
// Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
_balances[to] += value;
}
}
emit Transfer(from, to, value);
}
/**
* @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).
* Relies on the `_update` mechanism
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* NOTE: This function is not virtual, {_update} should be overridden instead.
*/
function _mint(address account, uint256 value) internal {
if (account == address(0)) {
revert ERC20InvalidReceiver(address(0));
}
_update(address(0), account, value);
}
/**
* @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.
* Relies on the `_update` mechanism.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* NOTE: This function is not virtual, {_update} should be overridden instead
*/
function _burn(address account, uint256 value) internal {
if (account == address(0)) {
revert ERC20InvalidSender(address(0));
}
_update(account, address(0), value);
}
/**
* @dev Sets `value` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*
* Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
*/
function _approve(address owner, address spender, uint256 value) internal {
_approve(owner, spender, value, true);
}
/**
* @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
*
* By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
* `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any
* `Approval` event during `transferFrom` operations.
*
* Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to
* true using the following override:
*
* ```solidity
* function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
* super._approve(owner, spender, value, true);
* }
* ```
*
* Requirements are the same as {_approve}.
*/
function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
if (owner == address(0)) {
revert ERC20InvalidApprover(address(0));
}
if (spender == address(0)) {
revert ERC20InvalidSpender(address(0));
}
_allowances[owner][spender] = value;
if (emitEvent) {
emit Approval(owner, spender, value);
}
}
/**
* @dev Updates `owner` s allowance for `spender` based on spent `value`.
*
* Does not update the allowance value in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Does not emit an {Approval} event.
*/
function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
if (currentAllowance < value) {
revert ERC20InsufficientAllowance(spender, currentAllowance, value);
}
unchecked {
_approve(owner, spender, currentAllowance - value, false);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.20;
import {IERC20} from "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC-20 standard.
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC-20 standard as defined in the ERC.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed 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.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the value of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the value of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 value) external returns (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.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets a `value` amount of tokens 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.
*/
function approve(address spender, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the
* allowance mechanism. `value` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 value) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)
pragma solidity ^0.8.20;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/introspection/ERC165.sol)
pragma solidity ^0.8.20;
import {IERC165} from "./IERC165.sol";
/**
* @dev Implementation of the {IERC165} interface.
*
* Contracts that want to implement ERC-165 should inherit from this contract and override {supportsInterface} to check
* for the additional interface id that will be supported. For example:
*
* ```solidity
* function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
* return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
* }
* ```
*/
abstract contract ERC165 is IERC165 {
/**
* @dev See {IERC165-supportsInterface}.
*/
function supportsInterface(bytes4 interfaceId) public view virtual returns (bool) {
return interfaceId == type(IERC165).interfaceId;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/introspection/IERC165.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC-165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[ERC].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[ERC section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.1.0) (utils/ReentrancyGuard.sol)
pragma solidity ^0.8.20;
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If EIP-1153 (transient storage) is available on the chain you're deploying at,
* consider using {ReentrancyGuardTransient} instead.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuard {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant NOT_ENTERED = 1;
uint256 private constant ENTERED = 2;
uint256 private _status;
/**
* @dev Unauthorized reentrant call.
*/
error ReentrancyGuardReentrantCall();
constructor() {
_status = NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
_nonReentrantBefore();
_;
_nonReentrantAfter();
}
function _nonReentrantBefore() private {
// On the first call to nonReentrant, _status will be NOT_ENTERED
if (_status == ENTERED) {
revert ReentrancyGuardReentrantCall();
}
// Any calls to nonReentrant after this point will fail
_status = ENTERED;
}
function _nonReentrantAfter() private {
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = NOT_ENTERED;
}
/**
* @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
* `nonReentrant` function in the call stack.
*/
function _reentrancyGuardEntered() internal view returns (bool) {
return _status == ENTERED;
}
}
pragma solidity >=0.5.0;
interface IUniswapV2Factory {
event PairCreated(address indexed token0, address indexed token1, address pair, uint);
function feeTo() external view returns (address);
function feeToSetter() external view returns (address);
function getPair(address tokenA, address tokenB) external view returns (address pair);
function allPairs(uint) external view returns (address pair);
function allPairsLength() external view returns (uint);
function createPair(address tokenA, address tokenB) external returns (address pair);
function setFeeTo(address) external;
function setFeeToSetter(address) external;
}
pragma solidity >=0.6.2;
interface IUniswapV2Router01 {
function factory() external pure returns (address);
function WETH() external pure returns (address);
function addLiquidity(
address tokenA,
address tokenB,
uint amountADesired,
uint amountBDesired,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB, uint liquidity);
function addLiquidityETH(
address token,
uint amountTokenDesired,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external payable returns (uint amountToken, uint amountETH, uint liquidity);
function removeLiquidity(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline
) external returns (uint amountA, uint amountB);
function removeLiquidityETH(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountToken, uint amountETH);
function removeLiquidityWithPermit(
address tokenA,
address tokenB,
uint liquidity,
uint amountAMin,
uint amountBMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountA, uint amountB);
function removeLiquidityETHWithPermit(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountToken, uint amountETH);
function swapExactTokensForTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapTokensForExactTokens(
uint amountOut,
uint amountInMax,
address[] calldata path,
address to,
uint deadline
) external returns (uint[] memory amounts);
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
external
returns (uint[] memory amounts);
function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01.sol';
interface IUniswapV2Router02 is IUniswapV2Router01 {
function removeLiquidityETHSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline
) external returns (uint amountETH);
function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
address token,
uint liquidity,
uint amountTokenMin,
uint amountETHMin,
address to,
uint deadline,
bool approveMax, uint8 v, bytes32 r, bytes32 s
) external returns (uint amountETH);
function swapExactTokensForTokensSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
function swapExactETHForTokensSupportingFeeOnTransferTokens(
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external payable;
function swapExactTokensForETHSupportingFeeOnTransferTokens(
uint amountIn,
uint amountOutMin,
address[] calldata path,
address to,
uint deadline
) external;
}
/*
██████╗ ██╗ ██╗██████╗ ██╗ ██╗
██╔════╝ ██║ ██║██╔══██╗██║ ██║
██║ ███╗██║ ██║██████╔╝██║ ██║
██║ ██║██║ ██║██╔══██╗██║ ██║
╚██████╔╝╚██████╔╝██║ ██║╚██████╔╝
╚═════╝ ╚═════╝ ╚═╝ ╚═╝ ╚═════╝
ERC20 Token
---------------------------------------------
Website https://guru.fund
Docs https://guru-fund.gitbook.io
Twitter https://x.com/thegurufund
Telegram https://t.me/guruportal
---------------------------------------------
*/
// SPDX-License-Identifier: MIT
import '@openzeppelin/contracts/access/Ownable.sol';
import '@openzeppelin/contracts/token/ERC20/ERC20.sol';
import '@openzeppelin/contracts/utils/Context.sol';
import '@openzeppelin/contracts/utils/ReentrancyGuard.sol';
import '@openzeppelin/contracts/access/AccessControl.sol';
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol';
import '@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol';
import 'contracts/helpers/TransferHelper.sol';
pragma solidity =0.8.27;
contract GURU is
Ownable,
ERC20,
TransferHelper,
ReentrancyGuard,
AccessControl
{
IUniswapV2Router02 public constant router =
IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
bytes32 private constant ADMIN_ROLE = keccak256('ADMIN_ROLE');
uint256 private constant SUPPLY = 100_000_000 * 10 ** 18;
bool private feeOnTransfer = true;
uint8 private kArMA = 10;
uint8 private burnFee = 0;
uint8 private vaultFee = 4;
uint8 private teamFee = 1;
address public uniswapV2Pair;
address public vault;
address public team;
uint256 public maxWallet = SUPPLY;
uint256 private swapThreshold = 50_000 * 10 ** 18;
/**
* @notice Addresses exempt from fees and max wallet size
*/
mapping(address => bool) public isExempt;
error Unauthorized();
error OnlyReducingFeesAllowed();
error StillMeditating();
error ChakraOverload(uint256 projectedBalance, uint256 maxWallet);
error KarmaMinimum();
constructor(
address _team,
address _vault,
address _governance
) Ownable(msg.sender) ERC20('Guru', 'GURU') {
_grantRole(ADMIN_ROLE, _governance);
isExempt[address(this)] = true;
isExempt[owner()] = true;
isExempt[_vault] = true;
_mint(_vault, (SUPPLY * 31) / 100);
_mint(address(this), (SUPPLY * 69) / 100);
team = _team;
vault = _vault;
}
receive() external payable {}
/// External functions
/**
* @notice [Owner] Creates a new pair, adds liquidity to it, and sets max wallet
*/
function enterNirvana() external onlyOwner {
address pair = IUniswapV2Factory(router.factory()).createPair(
address(this),
router.WETH()
);
_approve(address(this), address(router), balanceOf(address(this)));
router.addLiquidityETH{ value: address(this).balance }(
address(this),
balanceOf(address(this)),
0,
0,
owner(),
block.timestamp
);
uniswapV2Pair = pair;
maxWallet = SUPPLY / 100;
}
/**
* @notice [Owner] Slashes the karma fee. Only the owner can do this, until the fee is at minimum.
*/
function slashTheKarma() external onlyOwner {
require(kArMA > 1, KarmaMinimum());
unchecked {
--kArMA;
}
}
/**
* @notice [Owner] Manually triggers the burn and swap mechanism.
*/
function unclog() external onlyOwner {
_burnAndSwap(swapThreshold, getTotalFeeRate());
}
/**
* @notice [Admin] Reduces or rebalances the transfer fee allocations.
* Reverts if the new fees exceed the current total fees.
* @param newBurnFee The new burn fee
* @param newVaultFee The new vault fee
* @param newTeamFee The new team fee
*/
function reduceOrRebalanceFees(
uint8 newBurnFee,
uint8 newVaultFee,
uint8 newTeamFee
) external onlyRole(ADMIN_ROLE) {
require(
newBurnFee + newVaultFee + newTeamFee <= getTotalFeeRate(),
OnlyReducingFeesAllowed()
);
burnFee = newBurnFee;
vaultFee = newVaultFee;
teamFee = newTeamFee;
}
/**
* @notice [Admin] Updates the swap threshold amount.
* Setting it to 0 keeps the fee on transfer enabled, but disables the swap mechanism.
* @param value The new swap threshold amount
*/
function updateSwapThreshold(uint256 value) external onlyRole(ADMIN_ROLE) {
require(value <= SUPPLY / 50);
swapThreshold = value;
}
/**
* @notice [Admin] Toggles an address's exemption from fees and max wallet size
* @param account The address to toggle
*/
function toggleExemption(address account) external onlyRole(ADMIN_ROLE) {
isExempt[account] = !isExempt[account];
}
/**
* @notice [Admin] Toggles the fee on transfer. This does not affect buy/sell fees.
*/
function toggleFeeOnTransfer() external onlyRole(ADMIN_ROLE) {
feeOnTransfer = !feeOnTransfer;
}
/**
* @notice [Admin] Transfers the admin role
* @param newAdmin The new admin address
*/
function transferAdmin(address newAdmin) external onlyRole(ADMIN_ROLE) {
require(newAdmin != address(0));
_revokeRole(ADMIN_ROLE, msg.sender);
_grantRole(ADMIN_ROLE, newAdmin);
}
/**
* @notice [Admin] Updates the vault wallet
* @param newVault The new vault wallet
*/
function setVaultWallet(address newVault) external onlyRole(ADMIN_ROLE) {
vault = _applyWalletUpdate(vault, newVault);
}
/**
* @notice [Admin] Updates the team wallet
* @param newTeam The new team wallet
*/
function setTeamWallet(address newTeam) external onlyRole(ADMIN_ROLE) {
team = _applyWalletUpdate(team, newTeam);
}
/**
* @notice Burns tokens from the caller's balance
* @param amount The amount of tokens to burn
*/
function burn(uint256 amount) external {
_burn(msg.sender, amount);
}
// Public functions
/**
* @notice [Admin] Updates the max holding percent
* @param percent The new max holding percent
*/
function updateMaxHoldingPercent(
uint8 percent
) public onlyRole(ADMIN_ROLE) {
require(1 <= percent && percent <= 100);
maxWallet = (SUPPLY * percent) / 100;
}
/**
* @notice The current total transfer fee
*/
function getTotalFeeRate() public view returns (uint8) {
return (burnFee + vaultFee + teamFee) * kArMA;
}
// Internal functions
/**
* @notice Transfers are disabled until liquidity is added to the pair.
* @dev This function is used to handle fees on transfer.
* @param from The sender address
* @param to The recipient address
* @param amount The amount of tokens to transfer
*/
function _update(
address from,
address to,
uint256 amount
) internal override {
// When liquidity not added yet:
if (uniswapV2Pair == address(0)) {
require(
from == address(this) ||
from == address(0) ||
from == vault ||
to == vault,
StillMeditating()
);
super._update(from, to, amount);
return;
}
// No fees or max wallet size check if exempt
if (isExempt[from] || isExempt[to]) {
super._update(from, to, amount);
return;
}
// When liquidity has been added, max wallet size check (pair is exempt)
if (to != uniswapV2Pair) {
uint256 projectedBalance = super.balanceOf(to) + amount;
require(
projectedBalance <= maxWallet,
ChakraOverload(projectedBalance, maxWallet)
);
}
// Swap threshold check
uint8 feeRate = getTotalFeeRate();
if (
swapThreshold > 0 &&
balanceOf(address(this)) >= swapThreshold &&
from != uniswapV2Pair &&
(feeOnTransfer || to == uniswapV2Pair)
) {
_burnAndSwap(swapThreshold, feeRate);
}
if (feeRate > 0) {
uint256 feeTokens = (amount * feeRate) / 100;
amount -= feeTokens;
super._update(from, address(this), feeTokens);
}
// Continue with the transfer
super._update(from, to, amount);
}
// Private functions
/**
* @dev Internal function to handle wallet updates and credit transfers
*/
function _applyWalletUpdate(
address oldWallet,
address newWallet
) private returns (address) {
creditByAddress[newWallet] = creditByAddress[oldWallet];
delete creditByAddress[oldWallet];
return newWallet;
}
/**
* @notice Burns collected tokens and swaps the remaining for ETH
* @param tokenAmount The amount of tokens to swap
* @param feeRate The fee rate
*/
function _burnAndSwap(
uint256 tokenAmount,
uint8 feeRate
) private nonReentrant {
uint256 burnAmount = (tokenAmount * burnFee) / feeRate;
uint256 swapAmount = tokenAmount - burnAmount;
if (burnAmount > 0) {
_burn(address(this), burnAmount);
}
address[] memory path = new address[](2);
path[0] = address(this);
path[1] = router.WETH();
_approve(address(this), address(router), swapAmount);
router.swapExactTokensForETHSupportingFeeOnTransferTokens(
swapAmount,
0,
path,
address(this),
block.timestamp
);
uint256 balance = address(this).balance;
if (balance > 0) {
uint256 toTeam = (balance * teamFee) / (vaultFee + teamFee);
uint256 toVault = balance - toTeam;
_safeTransferETH(team, toTeam);
_safeTransferETH(vault, toVault);
}
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.27;
contract TransferHelper {
mapping(address => uint256) creditByAddress;
event CreditAdded(address indexed creditor, uint256 value);
event CreditWithdrawn(address indexed recipient, uint256 value);
error NativeTransferFailed();
/**
* @notice Safe transfer of ETH to an address. If the transfer fails, the value is added to the credit of the address.
* @param recipient The address to transfer ETH to
* @param value The amount of ETH to transfer
*/
function _safeTransferETH(address recipient, uint256 value) internal {
(bool success, ) = recipient.call{ value: value }('');
if (!success) {
creditByAddress[recipient] += value;
emit CreditAdded(recipient, value);
}
}
/**
* @notice Withdraws the caller's credit to the specified recipient. This transfer will either succeed or revert.
* @param recipient The address to transfer the ETH to
*/
function withdrawCredit(address recipient) external {
uint256 value = creditByAddress[msg.sender];
creditByAddress[msg.sender] = 0;
(bool success, ) = recipient.call{ value: value }('');
require(success, NativeTransferFailed());
emit CreditWithdrawn(recipient, value);
}
}