Contract Source Code:
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
constructor() {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. 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 {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (governance/utils/IVotes.sol)
pragma solidity ^0.8.0;
/**
* @dev Common interface for {ERC20Votes}, {ERC721Votes}, and other {Votes}-enabled contracts.
*
* _Available since v4.5._
*/
interface IVotes {
/**
* @dev Emitted when an account changes their delegate.
*/
event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);
/**
* @dev Emitted when a token transfer or delegate change results in changes to a delegate's number of votes.
*/
event DelegateVotesChanged(address indexed delegate, uint256 previousBalance, uint256 newBalance);
/**
* @dev Returns the current amount of votes that `account` has.
*/
function getVotes(address account) external view returns (uint256);
/**
* @dev Returns the amount of votes that `account` had at a specific moment in the past. If the `clock()` is
* configured to use block numbers, this will return the value at the end of the corresponding block.
*/
function getPastVotes(address account, uint256 timepoint) external view returns (uint256);
/**
* @dev Returns the total supply of votes available at a specific moment in the past. If the `clock()` is
* configured to use block numbers, this will return the value at the end of the corresponding block.
*
* NOTE: This value is the sum of all available votes, which is not necessarily the sum of all delegated votes.
* Votes that have not been delegated are still part of total supply, even though they would not participate in a
* vote.
*/
function getPastTotalSupply(uint256 timepoint) external view returns (uint256);
/**
* @dev Returns the delegate that `account` has chosen.
*/
function delegates(address account) external view returns (address);
/**
* @dev Delegates votes from the sender to `delegatee`.
*/
function delegate(address delegatee) external;
/**
* @dev Delegates votes from signer to `delegatee`.
*/
function delegateBySig(address delegatee, uint256 nonce, uint256 expiry, uint8 v, bytes32 r, bytes32 s) external;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5267.sol)
pragma solidity ^0.8.0;
interface IERC5267 {
/**
* @dev MAY be emitted to signal that the domain could have changed.
*/
event EIP712DomainChanged();
/**
* @dev returns the fields and values that describe the domain separator used by this contract for EIP-712
* signature.
*/
function eip712Domain()
external
view
returns (
bytes1 fields,
string memory name,
string memory version,
uint256 chainId,
address verifyingContract,
bytes32 salt,
uint256[] memory extensions
);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC5805.sol)
pragma solidity ^0.8.0;
import "../governance/utils/IVotes.sol";
import "./IERC6372.sol";
interface IERC5805 is IERC6372, IVotes {}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (interfaces/IERC6372.sol)
pragma solidity ^0.8.0;
interface IERC6372 {
/**
* @dev Clock used for flagging checkpoints. Can be overridden to implement timestamp based checkpoints (and voting).
*/
function clock() external view returns (uint48);
/**
* @dev Description of the clock
*/
// solhint-disable-next-line func-name-mixedcase
function CLOCK_MODE() external view returns (string memory);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.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}.
* For a generic mechanism see {ERC20PresetMinterPauser}.
*
* 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 ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is Context, IERC20, IERC20Metadata {
mapping(address => uint256) private _balances;
mapping(address => mapping(address => 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 override returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual override 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 override returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual override 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 `amount`.
*/
function transfer(address to, uint256 amount) public virtual override returns (bool) {
address owner = _msgSender();
_transfer(owner, to, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual override returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* NOTE: If `amount` 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 amount) public virtual override returns (bool) {
address owner = _msgSender();
_approve(owner, spender, amount);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* 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 `amount`.
* - the caller must have allowance for ``from``'s tokens of at least
* `amount`.
*/
function transferFrom(address from, address to, uint256 amount) public virtual override returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, amount);
_transfer(from, to, amount);
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
address owner = _msgSender();
_approve(owner, spender, allowance(owner, spender) + addedValue);
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
address owner = _msgSender();
uint256 currentAllowance = allowance(owner, spender);
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(owner, spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `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.
*
* Requirements:
*
* - `from` cannot be the zero address.
* - `to` cannot be the zero address.
* - `from` must have a balance of at least `amount`.
*/
function _transfer(address from, address to, uint256 amount) internal virtual {
require(from != address(0), "ERC20: transfer from the zero address");
require(to != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(from, to, amount);
uint256 fromBalance = _balances[from];
require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[from] = fromBalance - amount;
// Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
// decrementing then incrementing.
_balances[to] += amount;
}
emit Transfer(from, to, amount);
_afterTokenTransfer(from, to, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: mint to the zero address");
_beforeTokenTransfer(address(0), account, amount);
_totalSupply += amount;
unchecked {
// Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
_balances[account] += amount;
}
emit Transfer(address(0), account, amount);
_afterTokenTransfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements:
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 amount) internal virtual {
require(account != address(0), "ERC20: burn from the zero address");
_beforeTokenTransfer(account, address(0), amount);
uint256 accountBalance = _balances[account];
require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
unchecked {
_balances[account] = accountBalance - amount;
// Overflow not possible: amount <= accountBalance <= totalSupply.
_totalSupply -= amount;
}
emit Transfer(account, address(0), amount);
_afterTokenTransfer(account, address(0), amount);
}
/**
* @dev Sets `amount` 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.
*/
function _approve(address owner, address spender, uint256 amount) internal virtual {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
/**
* @dev Updates `owner` s allowance for `spender` based on spent `amount`.
*
* Does not update the allowance amount in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Might emit an {Approval} event.
*/
function _spendAllowance(address owner, address spender, uint256 amount) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
require(currentAllowance >= amount, "ERC20: insufficient allowance");
unchecked {
_approve(owner, spender, currentAllowance - amount);
}
}
}
/**
* @dev Hook that is called before any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* will be transferred to `to`.
* - when `from` is zero, `amount` tokens will be minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens 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(address from, address to, uint256 amount) internal virtual {}
/**
* @dev Hook that is called after any transfer of tokens. This includes
* minting and burning.
*
* Calling conditions:
*
* - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
* has been transferred to `to`.
* - when `from` is zero, `amount` tokens have been minted for `to`.
* - when `to` is zero, `amount` of ``from``'s tokens have been 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 _afterTokenTransfer(address from, address to, uint256 amount) internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)
pragma solidity ^0.8.0;
import "../ERC20.sol";
import "../../../utils/Context.sol";
/**
* @dev Extension of {ERC20} that allows token holders to destroy both their own
* tokens and those that they have an allowance for, in a way that can be
* recognized off-chain (via event analysis).
*/
abstract contract ERC20Burnable is Context, ERC20 {
/**
* @dev Destroys `amount` tokens from the caller.
*
* See {ERC20-_burn}.
*/
function burn(uint256 amount) public virtual {
_burn(_msgSender(), amount);
}
/**
* @dev Destroys `amount` tokens from `account`, deducting from the caller's
* allowance.
*
* See {ERC20-_burn} and {ERC20-allowance}.
*
* Requirements:
*
* - the caller must have allowance for ``accounts``'s tokens of at least
* `amount`.
*/
function burnFrom(address account, uint256 amount) public virtual {
_spendAllowance(account, _msgSender(), amount);
_burn(account, amount);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/ERC20Permit.sol)
pragma solidity ^0.8.0;
import "./IERC20Permit.sol";
import "../ERC20.sol";
import "../../../utils/cryptography/ECDSA.sol";
import "../../../utils/cryptography/EIP712.sol";
import "../../../utils/Counters.sol";
/**
* @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*
* _Available since v3.4._
*/
abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 {
using Counters for Counters.Counter;
mapping(address => Counters.Counter) private _nonces;
// solhint-disable-next-line var-name-mixedcase
bytes32 private constant _PERMIT_TYPEHASH =
keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
/**
* @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
* However, to ensure consistency with the upgradeable transpiler, we will continue
* to reserve a slot.
* @custom:oz-renamed-from _PERMIT_TYPEHASH
*/
// solhint-disable-next-line var-name-mixedcase
bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;
/**
* @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
*
* It's a good idea to use the same `name` that is defined as the ERC20 token name.
*/
constructor(string memory name) EIP712(name, "1") {}
/**
* @dev See {IERC20Permit-permit}.
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) public virtual override {
require(block.timestamp <= deadline, "ERC20Permit: expired deadline");
bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));
bytes32 hash = _hashTypedDataV4(structHash);
address signer = ECDSA.recover(hash, v, r, s);
require(signer == owner, "ERC20Permit: invalid signature");
_approve(owner, spender, value);
}
/**
* @dev See {IERC20Permit-nonces}.
*/
function nonces(address owner) public view virtual override returns (uint256) {
return _nonces[owner].current();
}
/**
* @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view override returns (bytes32) {
return _domainSeparatorV4();
}
/**
* @dev "Consume a nonce": return the current value and increment.
*
* _Available since v4.1._
*/
function _useNonce(address owner) internal virtual returns (uint256 current) {
Counters.Counter storage nonce = _nonces[owner];
current = nonce.current();
nonce.increment();
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/extensions/ERC20Votes.sol)
pragma solidity ^0.8.0;
import "./ERC20Permit.sol";
import "../../../interfaces/IERC5805.sol";
import "../../../utils/math/Math.sol";
import "../../../utils/math/SafeCast.sol";
import "../../../utils/cryptography/ECDSA.sol";
/**
* @dev Extension of ERC20 to support Compound-like voting and delegation. This version is more generic than Compound's,
* and supports token supply up to 2^224^ - 1, while COMP is limited to 2^96^ - 1.
*
* NOTE: If exact COMP compatibility is required, use the {ERC20VotesComp} variant of this module.
*
* This extension keeps a history (checkpoints) of each account's vote power. Vote power can be delegated either
* by calling the {delegate} function directly, or by providing a signature to be used with {delegateBySig}. Voting
* power can be queried through the public accessors {getVotes} and {getPastVotes}.
*
* By default, token balance does not account for voting power. This makes transfers cheaper. The downside is that it
* requires users to delegate to themselves in order to activate checkpoints and have their voting power tracked.
*
* _Available since v4.2._
*/
abstract contract ERC20Votes is ERC20Permit, IERC5805 {
struct Checkpoint {
uint32 fromBlock;
uint224 votes;
}
bytes32 private constant _DELEGATION_TYPEHASH =
keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");
mapping(address => address) private _delegates;
mapping(address => Checkpoint[]) private _checkpoints;
Checkpoint[] private _totalSupplyCheckpoints;
/**
* @dev Clock used for flagging checkpoints. Can be overridden to implement timestamp based checkpoints (and voting).
*/
function clock() public view virtual override returns (uint48) {
return SafeCast.toUint48(block.number);
}
/**
* @dev Description of the clock
*/
// solhint-disable-next-line func-name-mixedcase
function CLOCK_MODE() public view virtual override returns (string memory) {
// Check that the clock was not modified
require(clock() == block.number, "ERC20Votes: broken clock mode");
return "mode=blocknumber&from=default";
}
/**
* @dev Get the `pos`-th checkpoint for `account`.
*/
function checkpoints(address account, uint32 pos) public view virtual returns (Checkpoint memory) {
return _checkpoints[account][pos];
}
/**
* @dev Get number of checkpoints for `account`.
*/
function numCheckpoints(address account) public view virtual returns (uint32) {
return SafeCast.toUint32(_checkpoints[account].length);
}
/**
* @dev Get the address `account` is currently delegating to.
*/
function delegates(address account) public view virtual override returns (address) {
return _delegates[account];
}
/**
* @dev Gets the current votes balance for `account`
*/
function getVotes(address account) public view virtual override returns (uint256) {
uint256 pos = _checkpoints[account].length;
unchecked {
return pos == 0 ? 0 : _checkpoints[account][pos - 1].votes;
}
}
/**
* @dev Retrieve the number of votes for `account` at the end of `timepoint`.
*
* Requirements:
*
* - `timepoint` must be in the past
*/
function getPastVotes(address account, uint256 timepoint) public view virtual override returns (uint256) {
require(timepoint < clock(), "ERC20Votes: future lookup");
return _checkpointsLookup(_checkpoints[account], timepoint);
}
/**
* @dev Retrieve the `totalSupply` at the end of `timepoint`. Note, this value is the sum of all balances.
* It is NOT the sum of all the delegated votes!
*
* Requirements:
*
* - `timepoint` must be in the past
*/
function getPastTotalSupply(uint256 timepoint) public view virtual override returns (uint256) {
require(timepoint < clock(), "ERC20Votes: future lookup");
return _checkpointsLookup(_totalSupplyCheckpoints, timepoint);
}
/**
* @dev Lookup a value in a list of (sorted) checkpoints.
*/
function _checkpointsLookup(Checkpoint[] storage ckpts, uint256 timepoint) private view returns (uint256) {
// We run a binary search to look for the last (most recent) checkpoint taken before (or at) `timepoint`.
//
// Initially we check if the block is recent to narrow the search range.
// During the loop, the index of the wanted checkpoint remains in the range [low-1, high).
// With each iteration, either `low` or `high` is moved towards the middle of the range to maintain the invariant.
// - If the middle checkpoint is after `timepoint`, we look in [low, mid)
// - If the middle checkpoint is before or equal to `timepoint`, we look in [mid+1, high)
// Once we reach a single value (when low == high), we've found the right checkpoint at the index high-1, if not
// out of bounds (in which case we're looking too far in the past and the result is 0).
// Note that if the latest checkpoint available is exactly for `timepoint`, we end up with an index that is
// past the end of the array, so we technically don't find a checkpoint after `timepoint`, but it works out
// the same.
uint256 length = ckpts.length;
uint256 low = 0;
uint256 high = length;
if (length > 5) {
uint256 mid = length - Math.sqrt(length);
if (_unsafeAccess(ckpts, mid).fromBlock > timepoint) {
high = mid;
} else {
low = mid + 1;
}
}
while (low < high) {
uint256 mid = Math.average(low, high);
if (_unsafeAccess(ckpts, mid).fromBlock > timepoint) {
high = mid;
} else {
low = mid + 1;
}
}
unchecked {
return high == 0 ? 0 : _unsafeAccess(ckpts, high - 1).votes;
}
}
/**
* @dev Delegate votes from the sender to `delegatee`.
*/
function delegate(address delegatee) public virtual override {
_delegate(_msgSender(), delegatee);
}
/**
* @dev Delegates votes from signer to `delegatee`
*/
function delegateBySig(
address delegatee,
uint256 nonce,
uint256 expiry,
uint8 v,
bytes32 r,
bytes32 s
) public virtual override {
require(block.timestamp <= expiry, "ERC20Votes: signature expired");
address signer = ECDSA.recover(
_hashTypedDataV4(keccak256(abi.encode(_DELEGATION_TYPEHASH, delegatee, nonce, expiry))),
v,
r,
s
);
require(nonce == _useNonce(signer), "ERC20Votes: invalid nonce");
_delegate(signer, delegatee);
}
/**
* @dev Maximum token supply. Defaults to `type(uint224).max` (2^224^ - 1).
*/
function _maxSupply() internal view virtual returns (uint224) {
return type(uint224).max;
}
/**
* @dev Snapshots the totalSupply after it has been increased.
*/
function _mint(address account, uint256 amount) internal virtual override {
super._mint(account, amount);
require(totalSupply() <= _maxSupply(), "ERC20Votes: total supply risks overflowing votes");
_writeCheckpoint(_totalSupplyCheckpoints, _add, amount);
}
/**
* @dev Snapshots the totalSupply after it has been decreased.
*/
function _burn(address account, uint256 amount) internal virtual override {
super._burn(account, amount);
_writeCheckpoint(_totalSupplyCheckpoints, _subtract, amount);
}
/**
* @dev Move voting power when tokens are transferred.
*
* Emits a {IVotes-DelegateVotesChanged} event.
*/
function _afterTokenTransfer(address from, address to, uint256 amount) internal virtual override {
super._afterTokenTransfer(from, to, amount);
_moveVotingPower(delegates(from), delegates(to), amount);
}
/**
* @dev Change delegation for `delegator` to `delegatee`.
*
* Emits events {IVotes-DelegateChanged} and {IVotes-DelegateVotesChanged}.
*/
function _delegate(address delegator, address delegatee) internal virtual {
address currentDelegate = delegates(delegator);
uint256 delegatorBalance = balanceOf(delegator);
_delegates[delegator] = delegatee;
emit DelegateChanged(delegator, currentDelegate, delegatee);
_moveVotingPower(currentDelegate, delegatee, delegatorBalance);
}
function _moveVotingPower(address src, address dst, uint256 amount) private {
if (src != dst && amount > 0) {
if (src != address(0)) {
(uint256 oldWeight, uint256 newWeight) = _writeCheckpoint(_checkpoints[src], _subtract, amount);
emit DelegateVotesChanged(src, oldWeight, newWeight);
}
if (dst != address(0)) {
(uint256 oldWeight, uint256 newWeight) = _writeCheckpoint(_checkpoints[dst], _add, amount);
emit DelegateVotesChanged(dst, oldWeight, newWeight);
}
}
}
function _writeCheckpoint(
Checkpoint[] storage ckpts,
function(uint256, uint256) view returns (uint256) op,
uint256 delta
) private returns (uint256 oldWeight, uint256 newWeight) {
uint256 pos = ckpts.length;
unchecked {
Checkpoint memory oldCkpt = pos == 0 ? Checkpoint(0, 0) : _unsafeAccess(ckpts, pos - 1);
oldWeight = oldCkpt.votes;
newWeight = op(oldWeight, delta);
if (pos > 0 && oldCkpt.fromBlock == clock()) {
_unsafeAccess(ckpts, pos - 1).votes = SafeCast.toUint224(newWeight);
} else {
ckpts.push(Checkpoint({fromBlock: SafeCast.toUint32(clock()), votes: SafeCast.toUint224(newWeight)}));
}
}
}
function _add(uint256 a, uint256 b) private pure returns (uint256) {
return a + b;
}
function _subtract(uint256 a, uint256 b) private pure returns (uint256) {
return a - b;
}
/**
* @dev Access an element of the array without performing bounds check. The position is assumed to be within bounds.
*/
function _unsafeAccess(Checkpoint[] storage ckpts, uint256 pos) private pure returns (Checkpoint storage result) {
assembly {
mstore(0, ckpts.slot)
result.slot := add(keccak256(0, 0x20), pos)
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*
* _Available since v4.1._
*/
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 v4.9.0) (token/ERC20/extensions/IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
* https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
*
* Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
* presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
* need to send a transaction, and thus is not required to hold Ether at all.
*/
interface IERC20Permit {
/**
* @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
* given ``owner``'s signed approval.
*
* IMPORTANT: The same issues {IERC20-approve} has related to transaction
* ordering also apply here.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `deadline` must be a timestamp in the future.
* - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
* over the EIP712-formatted function arguments.
* - the signature must use ``owner``'s current nonce (see {nonces}).
*
* For more information on the signature format, see the
* https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
* section].
*/
function permit(
address owner,
address spender,
uint256 value,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external;
/**
* @dev Returns the current nonce for `owner`. This value must be
* included whenever a signature is generated for {permit}.
*
* Every successful call to {permit} increases ``owner``'s nonce by one. This
* prevents a signature from being used multiple times.
*/
function nonces(address owner) external view returns (uint256);
/**
* @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
*/
// solhint-disable-next-line func-name-mixedcase
function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
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 amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) 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 `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
pragma solidity ^0.8.0;
/**
* @title Counters
* @author Matt Condon (@shrugs)
* @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
* of elements in a mapping, issuing ERC721 ids, or counting request ids.
*
* Include with `using Counters for Counters.Counter;`
*/
library Counters {
struct Counter {
// This variable should never be directly accessed by users of the library: interactions must be restricted to
// the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
// this feature: see https://github.com/ethereum/solidity/issues/4637
uint256 _value; // default: 0
}
function current(Counter storage counter) internal view returns (uint256) {
return counter._value;
}
function increment(Counter storage counter) internal {
unchecked {
counter._value += 1;
}
}
function decrement(Counter storage counter) internal {
uint256 value = counter._value;
require(value > 0, "Counter: decrement overflow");
unchecked {
counter._value = value - 1;
}
}
function reset(Counter storage counter) internal {
counter._value = 0;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
import "../Strings.sol";
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV // Deprecated in v4.8
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
/// @solidity memory-safe-assembly
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 message) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
/// @solidity memory-safe-assembly
assembly {
mstore(0x00, "\x19Ethereum Signed Message:\n32")
mstore(0x1c, hash)
message := keccak256(0x00, 0x3c)
}
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 data) {
/// @solidity memory-safe-assembly
assembly {
let ptr := mload(0x40)
mstore(ptr, "\x19\x01")
mstore(add(ptr, 0x02), domainSeparator)
mstore(add(ptr, 0x22), structHash)
data := keccak256(ptr, 0x42)
}
}
/**
* @dev Returns an Ethereum Signed Data with intended validator, created from a
* `validator` and `data` according to the version 0 of EIP-191.
*
* See {recover}.
*/
function toDataWithIntendedValidatorHash(address validator, bytes memory data) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x00", validator, data));
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/cryptography/EIP712.sol)
pragma solidity ^0.8.8;
import "./ECDSA.sol";
import "../ShortStrings.sol";
import "../../interfaces/IERC5267.sol";
/**
* @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
*
* The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
* thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
* they need in their contracts using a combination of `abi.encode` and `keccak256`.
*
* This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
* scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
* ({_hashTypedDataV4}).
*
* The implementation of the domain separator was designed to be as efficient as possible while still properly updating
* the chain id to protect against replay attacks on an eventual fork of the chain.
*
* NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
* https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
*
* NOTE: In the upgradeable version of this contract, the cached values will correspond to the address, and the domain
* separator of the implementation contract. This will cause the `_domainSeparatorV4` function to always rebuild the
* separator from the immutable values, which is cheaper than accessing a cached version in cold storage.
*
* _Available since v3.4._
*
* @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
*/
abstract contract EIP712 is IERC5267 {
using ShortStrings for *;
bytes32 private constant _TYPE_HASH =
keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
// Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
// invalidate the cached domain separator if the chain id changes.
bytes32 private immutable _cachedDomainSeparator;
uint256 private immutable _cachedChainId;
address private immutable _cachedThis;
bytes32 private immutable _hashedName;
bytes32 private immutable _hashedVersion;
ShortString private immutable _name;
ShortString private immutable _version;
string private _nameFallback;
string private _versionFallback;
/**
* @dev Initializes the domain separator and parameter caches.
*
* The meaning of `name` and `version` is specified in
* https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
*
* - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
* - `version`: the current major version of the signing domain.
*
* NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
* contract upgrade].
*/
constructor(string memory name, string memory version) {
_name = name.toShortStringWithFallback(_nameFallback);
_version = version.toShortStringWithFallback(_versionFallback);
_hashedName = keccak256(bytes(name));
_hashedVersion = keccak256(bytes(version));
_cachedChainId = block.chainid;
_cachedDomainSeparator = _buildDomainSeparator();
_cachedThis = address(this);
}
/**
* @dev Returns the domain separator for the current chain.
*/
function _domainSeparatorV4() internal view returns (bytes32) {
if (address(this) == _cachedThis && block.chainid == _cachedChainId) {
return _cachedDomainSeparator;
} else {
return _buildDomainSeparator();
}
}
function _buildDomainSeparator() private view returns (bytes32) {
return keccak256(abi.encode(_TYPE_HASH, _hashedName, _hashedVersion, block.chainid, address(this)));
}
/**
* @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
* function returns the hash of the fully encoded EIP712 message for this domain.
*
* This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
*
* ```solidity
* bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
* keccak256("Mail(address to,string contents)"),
* mailTo,
* keccak256(bytes(mailContents))
* )));
* address signer = ECDSA.recover(digest, signature);
* ```
*/
function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
}
/**
* @dev See {EIP-5267}.
*
* _Available since v4.9._
*/
function eip712Domain()
public
view
virtual
override
returns (
bytes1 fields,
string memory name,
string memory version,
uint256 chainId,
address verifyingContract,
bytes32 salt,
uint256[] memory extensions
)
{
return (
hex"0f", // 01111
_name.toStringWithFallback(_nameFallback),
_version.toStringWithFallback(_versionFallback),
block.chainid,
address(this),
bytes32(0),
new uint256[](0)
);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC165 standard, as defined in the
* https://eips.ethereum.org/EIPS/eip-165[EIP].
*
* Implementers can declare support of contract interfaces, which can then be
* queried by others ({ERC165Checker}).
*
* For an implementation, see {ERC165}.
*/
interface IERC165 {
/**
* @dev Returns true if this contract implements the interface defined by
* `interfaceId`. See the corresponding
* https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
* to learn more about how these ids are created.
*
* This function call must use less than 30 000 gas.
*/
function supportsInterface(bytes4 interfaceId) external view returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)
pragma solidity ^0.8.0;
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
enum Rounding {
Down, // Toward negative infinity
Up, // Toward infinity
Zero // Toward zero
}
/**
* @dev Returns the largest of two numbers.
*/
function max(uint256 a, uint256 b) internal pure returns (uint256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two numbers.
*/
function min(uint256 a, uint256 b) internal pure returns (uint256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two numbers. The result is rounded towards
* zero.
*/
function average(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b) / 2 can overflow.
return (a & b) + (a ^ b) / 2;
}
/**
* @dev Returns the ceiling of the division of two numbers.
*
* This differs from standard division with `/` in that it rounds up instead
* of rounding down.
*/
function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
// (a + b - 1) / b can overflow on addition, so we distribute.
return a == 0 ? 0 : (a - 1) / b + 1;
}
/**
* @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
* @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
* with further edits by Uniswap Labs also under MIT license.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
unchecked {
// 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
// use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
// variables such that product = prod1 * 2^256 + prod0.
uint256 prod0; // Least significant 256 bits of the product
uint256 prod1; // Most significant 256 bits of the product
assembly {
let mm := mulmod(x, y, not(0))
prod0 := mul(x, y)
prod1 := sub(sub(mm, prod0), lt(mm, prod0))
}
// Handle non-overflow cases, 256 by 256 division.
if (prod1 == 0) {
// Solidity will revert if denominator == 0, unlike the div opcode on its own.
// The surrounding unchecked block does not change this fact.
// See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
return prod0 / denominator;
}
// Make sure the result is less than 2^256. Also prevents denominator == 0.
require(denominator > prod1, "Math: mulDiv overflow");
///////////////////////////////////////////////
// 512 by 256 division.
///////////////////////////////////////////////
// Make division exact by subtracting the remainder from [prod1 prod0].
uint256 remainder;
assembly {
// Compute remainder using mulmod.
remainder := mulmod(x, y, denominator)
// Subtract 256 bit number from 512 bit number.
prod1 := sub(prod1, gt(remainder, prod0))
prod0 := sub(prod0, remainder)
}
// Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
// See https://cs.stackexchange.com/q/138556/92363.
// Does not overflow because the denominator cannot be zero at this stage in the function.
uint256 twos = denominator & (~denominator + 1);
assembly {
// Divide denominator by twos.
denominator := div(denominator, twos)
// Divide [prod1 prod0] by twos.
prod0 := div(prod0, twos)
// Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
twos := add(div(sub(0, twos), twos), 1)
}
// Shift in bits from prod1 into prod0.
prod0 |= prod1 * twos;
// Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
// that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
// four bits. That is, denominator * inv = 1 mod 2^4.
uint256 inverse = (3 * denominator) ^ 2;
// Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
// in modular arithmetic, doubling the correct bits in each step.
inverse *= 2 - denominator * inverse; // inverse mod 2^8
inverse *= 2 - denominator * inverse; // inverse mod 2^16
inverse *= 2 - denominator * inverse; // inverse mod 2^32
inverse *= 2 - denominator * inverse; // inverse mod 2^64
inverse *= 2 - denominator * inverse; // inverse mod 2^128
inverse *= 2 - denominator * inverse; // inverse mod 2^256
// Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
// This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
// less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
// is no longer required.
result = prod0 * inverse;
return result;
}
}
/**
* @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
*/
function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
uint256 result = mulDiv(x, y, denominator);
if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
result += 1;
}
return result;
}
/**
* @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
*
* Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
*/
function sqrt(uint256 a) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
// For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
//
// We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
// `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
//
// This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
// → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
// → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
//
// Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
uint256 result = 1 << (log2(a) >> 1);
// At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
// since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
// every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
// into the expected uint128 result.
unchecked {
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
result = (result + a / result) >> 1;
return min(result, a / result);
}
}
/**
* @notice Calculates sqrt(a), following the selected rounding direction.
*/
function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = sqrt(a);
return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
}
}
/**
* @dev Return the log in base 2, rounded down, of a positive value.
* Returns 0 if given 0.
*/
function log2(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >> 128 > 0) {
value >>= 128;
result += 128;
}
if (value >> 64 > 0) {
value >>= 64;
result += 64;
}
if (value >> 32 > 0) {
value >>= 32;
result += 32;
}
if (value >> 16 > 0) {
value >>= 16;
result += 16;
}
if (value >> 8 > 0) {
value >>= 8;
result += 8;
}
if (value >> 4 > 0) {
value >>= 4;
result += 4;
}
if (value >> 2 > 0) {
value >>= 2;
result += 2;
}
if (value >> 1 > 0) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 2, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log2(value);
return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 10, rounded down, of a positive value.
* Returns 0 if given 0.
*/
function log10(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >= 10 ** 64) {
value /= 10 ** 64;
result += 64;
}
if (value >= 10 ** 32) {
value /= 10 ** 32;
result += 32;
}
if (value >= 10 ** 16) {
value /= 10 ** 16;
result += 16;
}
if (value >= 10 ** 8) {
value /= 10 ** 8;
result += 8;
}
if (value >= 10 ** 4) {
value /= 10 ** 4;
result += 4;
}
if (value >= 10 ** 2) {
value /= 10 ** 2;
result += 2;
}
if (value >= 10 ** 1) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 10, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log10(value);
return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
}
}
/**
* @dev Return the log in base 256, rounded down, of a positive value.
* Returns 0 if given 0.
*
* Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
*/
function log256(uint256 value) internal pure returns (uint256) {
uint256 result = 0;
unchecked {
if (value >> 128 > 0) {
value >>= 128;
result += 16;
}
if (value >> 64 > 0) {
value >>= 64;
result += 8;
}
if (value >> 32 > 0) {
value >>= 32;
result += 4;
}
if (value >> 16 > 0) {
value >>= 16;
result += 2;
}
if (value >> 8 > 0) {
result += 1;
}
}
return result;
}
/**
* @dev Return the log in base 256, following the selected rounding direction, of a positive value.
* Returns 0 if given 0.
*/
function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
unchecked {
uint256 result = log256(value);
return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SafeCast.sol)
// This file was procedurally generated from scripts/generate/templates/SafeCast.js.
pragma solidity ^0.8.0;
/**
* @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
* checks.
*
* Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
* easily result in undesired exploitation or bugs, since developers usually
* assume that overflows raise errors. `SafeCast` restores this intuition by
* reverting the transaction when such an operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*
* Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
* all math on `uint256` and `int256` and then downcasting.
*/
library SafeCast {
/**
* @dev Returns the downcasted uint248 from uint256, reverting on
* overflow (when the input is greater than largest uint248).
*
* Counterpart to Solidity's `uint248` operator.
*
* Requirements:
*
* - input must fit into 248 bits
*
* _Available since v4.7._
*/
function toUint248(uint256 value) internal pure returns (uint248) {
require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
return uint248(value);
}
/**
* @dev Returns the downcasted uint240 from uint256, reverting on
* overflow (when the input is greater than largest uint240).
*
* Counterpart to Solidity's `uint240` operator.
*
* Requirements:
*
* - input must fit into 240 bits
*
* _Available since v4.7._
*/
function toUint240(uint256 value) internal pure returns (uint240) {
require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
return uint240(value);
}
/**
* @dev Returns the downcasted uint232 from uint256, reverting on
* overflow (when the input is greater than largest uint232).
*
* Counterpart to Solidity's `uint232` operator.
*
* Requirements:
*
* - input must fit into 232 bits
*
* _Available since v4.7._
*/
function toUint232(uint256 value) internal pure returns (uint232) {
require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
return uint232(value);
}
/**
* @dev Returns the downcasted uint224 from uint256, reverting on
* overflow (when the input is greater than largest uint224).
*
* Counterpart to Solidity's `uint224` operator.
*
* Requirements:
*
* - input must fit into 224 bits
*
* _Available since v4.2._
*/
function toUint224(uint256 value) internal pure returns (uint224) {
require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
return uint224(value);
}
/**
* @dev Returns the downcasted uint216 from uint256, reverting on
* overflow (when the input is greater than largest uint216).
*
* Counterpart to Solidity's `uint216` operator.
*
* Requirements:
*
* - input must fit into 216 bits
*
* _Available since v4.7._
*/
function toUint216(uint256 value) internal pure returns (uint216) {
require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
return uint216(value);
}
/**
* @dev Returns the downcasted uint208 from uint256, reverting on
* overflow (when the input is greater than largest uint208).
*
* Counterpart to Solidity's `uint208` operator.
*
* Requirements:
*
* - input must fit into 208 bits
*
* _Available since v4.7._
*/
function toUint208(uint256 value) internal pure returns (uint208) {
require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
return uint208(value);
}
/**
* @dev Returns the downcasted uint200 from uint256, reverting on
* overflow (when the input is greater than largest uint200).
*
* Counterpart to Solidity's `uint200` operator.
*
* Requirements:
*
* - input must fit into 200 bits
*
* _Available since v4.7._
*/
function toUint200(uint256 value) internal pure returns (uint200) {
require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
return uint200(value);
}
/**
* @dev Returns the downcasted uint192 from uint256, reverting on
* overflow (when the input is greater than largest uint192).
*
* Counterpart to Solidity's `uint192` operator.
*
* Requirements:
*
* - input must fit into 192 bits
*
* _Available since v4.7._
*/
function toUint192(uint256 value) internal pure returns (uint192) {
require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
return uint192(value);
}
/**
* @dev Returns the downcasted uint184 from uint256, reverting on
* overflow (when the input is greater than largest uint184).
*
* Counterpart to Solidity's `uint184` operator.
*
* Requirements:
*
* - input must fit into 184 bits
*
* _Available since v4.7._
*/
function toUint184(uint256 value) internal pure returns (uint184) {
require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
return uint184(value);
}
/**
* @dev Returns the downcasted uint176 from uint256, reverting on
* overflow (when the input is greater than largest uint176).
*
* Counterpart to Solidity's `uint176` operator.
*
* Requirements:
*
* - input must fit into 176 bits
*
* _Available since v4.7._
*/
function toUint176(uint256 value) internal pure returns (uint176) {
require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
return uint176(value);
}
/**
* @dev Returns the downcasted uint168 from uint256, reverting on
* overflow (when the input is greater than largest uint168).
*
* Counterpart to Solidity's `uint168` operator.
*
* Requirements:
*
* - input must fit into 168 bits
*
* _Available since v4.7._
*/
function toUint168(uint256 value) internal pure returns (uint168) {
require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
return uint168(value);
}
/**
* @dev Returns the downcasted uint160 from uint256, reverting on
* overflow (when the input is greater than largest uint160).
*
* Counterpart to Solidity's `uint160` operator.
*
* Requirements:
*
* - input must fit into 160 bits
*
* _Available since v4.7._
*/
function toUint160(uint256 value) internal pure returns (uint160) {
require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
return uint160(value);
}
/**
* @dev Returns the downcasted uint152 from uint256, reverting on
* overflow (when the input is greater than largest uint152).
*
* Counterpart to Solidity's `uint152` operator.
*
* Requirements:
*
* - input must fit into 152 bits
*
* _Available since v4.7._
*/
function toUint152(uint256 value) internal pure returns (uint152) {
require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
return uint152(value);
}
/**
* @dev Returns the downcasted uint144 from uint256, reverting on
* overflow (when the input is greater than largest uint144).
*
* Counterpart to Solidity's `uint144` operator.
*
* Requirements:
*
* - input must fit into 144 bits
*
* _Available since v4.7._
*/
function toUint144(uint256 value) internal pure returns (uint144) {
require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
return uint144(value);
}
/**
* @dev Returns the downcasted uint136 from uint256, reverting on
* overflow (when the input is greater than largest uint136).
*
* Counterpart to Solidity's `uint136` operator.
*
* Requirements:
*
* - input must fit into 136 bits
*
* _Available since v4.7._
*/
function toUint136(uint256 value) internal pure returns (uint136) {
require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
return uint136(value);
}
/**
* @dev Returns the downcasted uint128 from uint256, reverting on
* overflow (when the input is greater than largest uint128).
*
* Counterpart to Solidity's `uint128` operator.
*
* Requirements:
*
* - input must fit into 128 bits
*
* _Available since v2.5._
*/
function toUint128(uint256 value) internal pure returns (uint128) {
require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
return uint128(value);
}
/**
* @dev Returns the downcasted uint120 from uint256, reverting on
* overflow (when the input is greater than largest uint120).
*
* Counterpart to Solidity's `uint120` operator.
*
* Requirements:
*
* - input must fit into 120 bits
*
* _Available since v4.7._
*/
function toUint120(uint256 value) internal pure returns (uint120) {
require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
return uint120(value);
}
/**
* @dev Returns the downcasted uint112 from uint256, reverting on
* overflow (when the input is greater than largest uint112).
*
* Counterpart to Solidity's `uint112` operator.
*
* Requirements:
*
* - input must fit into 112 bits
*
* _Available since v4.7._
*/
function toUint112(uint256 value) internal pure returns (uint112) {
require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
return uint112(value);
}
/**
* @dev Returns the downcasted uint104 from uint256, reverting on
* overflow (when the input is greater than largest uint104).
*
* Counterpart to Solidity's `uint104` operator.
*
* Requirements:
*
* - input must fit into 104 bits
*
* _Available since v4.7._
*/
function toUint104(uint256 value) internal pure returns (uint104) {
require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
return uint104(value);
}
/**
* @dev Returns the downcasted uint96 from uint256, reverting on
* overflow (when the input is greater than largest uint96).
*
* Counterpart to Solidity's `uint96` operator.
*
* Requirements:
*
* - input must fit into 96 bits
*
* _Available since v4.2._
*/
function toUint96(uint256 value) internal pure returns (uint96) {
require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
return uint96(value);
}
/**
* @dev Returns the downcasted uint88 from uint256, reverting on
* overflow (when the input is greater than largest uint88).
*
* Counterpart to Solidity's `uint88` operator.
*
* Requirements:
*
* - input must fit into 88 bits
*
* _Available since v4.7._
*/
function toUint88(uint256 value) internal pure returns (uint88) {
require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
return uint88(value);
}
/**
* @dev Returns the downcasted uint80 from uint256, reverting on
* overflow (when the input is greater than largest uint80).
*
* Counterpart to Solidity's `uint80` operator.
*
* Requirements:
*
* - input must fit into 80 bits
*
* _Available since v4.7._
*/
function toUint80(uint256 value) internal pure returns (uint80) {
require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
return uint80(value);
}
/**
* @dev Returns the downcasted uint72 from uint256, reverting on
* overflow (when the input is greater than largest uint72).
*
* Counterpart to Solidity's `uint72` operator.
*
* Requirements:
*
* - input must fit into 72 bits
*
* _Available since v4.7._
*/
function toUint72(uint256 value) internal pure returns (uint72) {
require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
return uint72(value);
}
/**
* @dev Returns the downcasted uint64 from uint256, reverting on
* overflow (when the input is greater than largest uint64).
*
* Counterpart to Solidity's `uint64` operator.
*
* Requirements:
*
* - input must fit into 64 bits
*
* _Available since v2.5._
*/
function toUint64(uint256 value) internal pure returns (uint64) {
require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
return uint64(value);
}
/**
* @dev Returns the downcasted uint56 from uint256, reverting on
* overflow (when the input is greater than largest uint56).
*
* Counterpart to Solidity's `uint56` operator.
*
* Requirements:
*
* - input must fit into 56 bits
*
* _Available since v4.7._
*/
function toUint56(uint256 value) internal pure returns (uint56) {
require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
return uint56(value);
}
/**
* @dev Returns the downcasted uint48 from uint256, reverting on
* overflow (when the input is greater than largest uint48).
*
* Counterpart to Solidity's `uint48` operator.
*
* Requirements:
*
* - input must fit into 48 bits
*
* _Available since v4.7._
*/
function toUint48(uint256 value) internal pure returns (uint48) {
require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
return uint48(value);
}
/**
* @dev Returns the downcasted uint40 from uint256, reverting on
* overflow (when the input is greater than largest uint40).
*
* Counterpart to Solidity's `uint40` operator.
*
* Requirements:
*
* - input must fit into 40 bits
*
* _Available since v4.7._
*/
function toUint40(uint256 value) internal pure returns (uint40) {
require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
return uint40(value);
}
/**
* @dev Returns the downcasted uint32 from uint256, reverting on
* overflow (when the input is greater than largest uint32).
*
* Counterpart to Solidity's `uint32` operator.
*
* Requirements:
*
* - input must fit into 32 bits
*
* _Available since v2.5._
*/
function toUint32(uint256 value) internal pure returns (uint32) {
require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
return uint32(value);
}
/**
* @dev Returns the downcasted uint24 from uint256, reverting on
* overflow (when the input is greater than largest uint24).
*
* Counterpart to Solidity's `uint24` operator.
*
* Requirements:
*
* - input must fit into 24 bits
*
* _Available since v4.7._
*/
function toUint24(uint256 value) internal pure returns (uint24) {
require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
return uint24(value);
}
/**
* @dev Returns the downcasted uint16 from uint256, reverting on
* overflow (when the input is greater than largest uint16).
*
* Counterpart to Solidity's `uint16` operator.
*
* Requirements:
*
* - input must fit into 16 bits
*
* _Available since v2.5._
*/
function toUint16(uint256 value) internal pure returns (uint16) {
require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
return uint16(value);
}
/**
* @dev Returns the downcasted uint8 from uint256, reverting on
* overflow (when the input is greater than largest uint8).
*
* Counterpart to Solidity's `uint8` operator.
*
* Requirements:
*
* - input must fit into 8 bits
*
* _Available since v2.5._
*/
function toUint8(uint256 value) internal pure returns (uint8) {
require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
return uint8(value);
}
/**
* @dev Converts a signed int256 into an unsigned uint256.
*
* Requirements:
*
* - input must be greater than or equal to 0.
*
* _Available since v3.0._
*/
function toUint256(int256 value) internal pure returns (uint256) {
require(value >= 0, "SafeCast: value must be positive");
return uint256(value);
}
/**
* @dev Returns the downcasted int248 from int256, reverting on
* overflow (when the input is less than smallest int248 or
* greater than largest int248).
*
* Counterpart to Solidity's `int248` operator.
*
* Requirements:
*
* - input must fit into 248 bits
*
* _Available since v4.7._
*/
function toInt248(int256 value) internal pure returns (int248 downcasted) {
downcasted = int248(value);
require(downcasted == value, "SafeCast: value doesn't fit in 248 bits");
}
/**
* @dev Returns the downcasted int240 from int256, reverting on
* overflow (when the input is less than smallest int240 or
* greater than largest int240).
*
* Counterpart to Solidity's `int240` operator.
*
* Requirements:
*
* - input must fit into 240 bits
*
* _Available since v4.7._
*/
function toInt240(int256 value) internal pure returns (int240 downcasted) {
downcasted = int240(value);
require(downcasted == value, "SafeCast: value doesn't fit in 240 bits");
}
/**
* @dev Returns the downcasted int232 from int256, reverting on
* overflow (when the input is less than smallest int232 or
* greater than largest int232).
*
* Counterpart to Solidity's `int232` operator.
*
* Requirements:
*
* - input must fit into 232 bits
*
* _Available since v4.7._
*/
function toInt232(int256 value) internal pure returns (int232 downcasted) {
downcasted = int232(value);
require(downcasted == value, "SafeCast: value doesn't fit in 232 bits");
}
/**
* @dev Returns the downcasted int224 from int256, reverting on
* overflow (when the input is less than smallest int224 or
* greater than largest int224).
*
* Counterpart to Solidity's `int224` operator.
*
* Requirements:
*
* - input must fit into 224 bits
*
* _Available since v4.7._
*/
function toInt224(int256 value) internal pure returns (int224 downcasted) {
downcasted = int224(value);
require(downcasted == value, "SafeCast: value doesn't fit in 224 bits");
}
/**
* @dev Returns the downcasted int216 from int256, reverting on
* overflow (when the input is less than smallest int216 or
* greater than largest int216).
*
* Counterpart to Solidity's `int216` operator.
*
* Requirements:
*
* - input must fit into 216 bits
*
* _Available since v4.7._
*/
function toInt216(int256 value) internal pure returns (int216 downcasted) {
downcasted = int216(value);
require(downcasted == value, "SafeCast: value doesn't fit in 216 bits");
}
/**
* @dev Returns the downcasted int208 from int256, reverting on
* overflow (when the input is less than smallest int208 or
* greater than largest int208).
*
* Counterpart to Solidity's `int208` operator.
*
* Requirements:
*
* - input must fit into 208 bits
*
* _Available since v4.7._
*/
function toInt208(int256 value) internal pure returns (int208 downcasted) {
downcasted = int208(value);
require(downcasted == value, "SafeCast: value doesn't fit in 208 bits");
}
/**
* @dev Returns the downcasted int200 from int256, reverting on
* overflow (when the input is less than smallest int200 or
* greater than largest int200).
*
* Counterpart to Solidity's `int200` operator.
*
* Requirements:
*
* - input must fit into 200 bits
*
* _Available since v4.7._
*/
function toInt200(int256 value) internal pure returns (int200 downcasted) {
downcasted = int200(value);
require(downcasted == value, "SafeCast: value doesn't fit in 200 bits");
}
/**
* @dev Returns the downcasted int192 from int256, reverting on
* overflow (when the input is less than smallest int192 or
* greater than largest int192).
*
* Counterpart to Solidity's `int192` operator.
*
* Requirements:
*
* - input must fit into 192 bits
*
* _Available since v4.7._
*/
function toInt192(int256 value) internal pure returns (int192 downcasted) {
downcasted = int192(value);
require(downcasted == value, "SafeCast: value doesn't fit in 192 bits");
}
/**
* @dev Returns the downcasted int184 from int256, reverting on
* overflow (when the input is less than smallest int184 or
* greater than largest int184).
*
* Counterpart to Solidity's `int184` operator.
*
* Requirements:
*
* - input must fit into 184 bits
*
* _Available since v4.7._
*/
function toInt184(int256 value) internal pure returns (int184 downcasted) {
downcasted = int184(value);
require(downcasted == value, "SafeCast: value doesn't fit in 184 bits");
}
/**
* @dev Returns the downcasted int176 from int256, reverting on
* overflow (when the input is less than smallest int176 or
* greater than largest int176).
*
* Counterpart to Solidity's `int176` operator.
*
* Requirements:
*
* - input must fit into 176 bits
*
* _Available since v4.7._
*/
function toInt176(int256 value) internal pure returns (int176 downcasted) {
downcasted = int176(value);
require(downcasted == value, "SafeCast: value doesn't fit in 176 bits");
}
/**
* @dev Returns the downcasted int168 from int256, reverting on
* overflow (when the input is less than smallest int168 or
* greater than largest int168).
*
* Counterpart to Solidity's `int168` operator.
*
* Requirements:
*
* - input must fit into 168 bits
*
* _Available since v4.7._
*/
function toInt168(int256 value) internal pure returns (int168 downcasted) {
downcasted = int168(value);
require(downcasted == value, "SafeCast: value doesn't fit in 168 bits");
}
/**
* @dev Returns the downcasted int160 from int256, reverting on
* overflow (when the input is less than smallest int160 or
* greater than largest int160).
*
* Counterpart to Solidity's `int160` operator.
*
* Requirements:
*
* - input must fit into 160 bits
*
* _Available since v4.7._
*/
function toInt160(int256 value) internal pure returns (int160 downcasted) {
downcasted = int160(value);
require(downcasted == value, "SafeCast: value doesn't fit in 160 bits");
}
/**
* @dev Returns the downcasted int152 from int256, reverting on
* overflow (when the input is less than smallest int152 or
* greater than largest int152).
*
* Counterpart to Solidity's `int152` operator.
*
* Requirements:
*
* - input must fit into 152 bits
*
* _Available since v4.7._
*/
function toInt152(int256 value) internal pure returns (int152 downcasted) {
downcasted = int152(value);
require(downcasted == value, "SafeCast: value doesn't fit in 152 bits");
}
/**
* @dev Returns the downcasted int144 from int256, reverting on
* overflow (when the input is less than smallest int144 or
* greater than largest int144).
*
* Counterpart to Solidity's `int144` operator.
*
* Requirements:
*
* - input must fit into 144 bits
*
* _Available since v4.7._
*/
function toInt144(int256 value) internal pure returns (int144 downcasted) {
downcasted = int144(value);
require(downcasted == value, "SafeCast: value doesn't fit in 144 bits");
}
/**
* @dev Returns the downcasted int136 from int256, reverting on
* overflow (when the input is less than smallest int136 or
* greater than largest int136).
*
* Counterpart to Solidity's `int136` operator.
*
* Requirements:
*
* - input must fit into 136 bits
*
* _Available since v4.7._
*/
function toInt136(int256 value) internal pure returns (int136 downcasted) {
downcasted = int136(value);
require(downcasted == value, "SafeCast: value doesn't fit in 136 bits");
}
/**
* @dev Returns the downcasted int128 from int256, reverting on
* overflow (when the input is less than smallest int128 or
* greater than largest int128).
*
* Counterpart to Solidity's `int128` operator.
*
* Requirements:
*
* - input must fit into 128 bits
*
* _Available since v3.1._
*/
function toInt128(int256 value) internal pure returns (int128 downcasted) {
downcasted = int128(value);
require(downcasted == value, "SafeCast: value doesn't fit in 128 bits");
}
/**
* @dev Returns the downcasted int120 from int256, reverting on
* overflow (when the input is less than smallest int120 or
* greater than largest int120).
*
* Counterpart to Solidity's `int120` operator.
*
* Requirements:
*
* - input must fit into 120 bits
*
* _Available since v4.7._
*/
function toInt120(int256 value) internal pure returns (int120 downcasted) {
downcasted = int120(value);
require(downcasted == value, "SafeCast: value doesn't fit in 120 bits");
}
/**
* @dev Returns the downcasted int112 from int256, reverting on
* overflow (when the input is less than smallest int112 or
* greater than largest int112).
*
* Counterpart to Solidity's `int112` operator.
*
* Requirements:
*
* - input must fit into 112 bits
*
* _Available since v4.7._
*/
function toInt112(int256 value) internal pure returns (int112 downcasted) {
downcasted = int112(value);
require(downcasted == value, "SafeCast: value doesn't fit in 112 bits");
}
/**
* @dev Returns the downcasted int104 from int256, reverting on
* overflow (when the input is less than smallest int104 or
* greater than largest int104).
*
* Counterpart to Solidity's `int104` operator.
*
* Requirements:
*
* - input must fit into 104 bits
*
* _Available since v4.7._
*/
function toInt104(int256 value) internal pure returns (int104 downcasted) {
downcasted = int104(value);
require(downcasted == value, "SafeCast: value doesn't fit in 104 bits");
}
/**
* @dev Returns the downcasted int96 from int256, reverting on
* overflow (when the input is less than smallest int96 or
* greater than largest int96).
*
* Counterpart to Solidity's `int96` operator.
*
* Requirements:
*
* - input must fit into 96 bits
*
* _Available since v4.7._
*/
function toInt96(int256 value) internal pure returns (int96 downcasted) {
downcasted = int96(value);
require(downcasted == value, "SafeCast: value doesn't fit in 96 bits");
}
/**
* @dev Returns the downcasted int88 from int256, reverting on
* overflow (when the input is less than smallest int88 or
* greater than largest int88).
*
* Counterpart to Solidity's `int88` operator.
*
* Requirements:
*
* - input must fit into 88 bits
*
* _Available since v4.7._
*/
function toInt88(int256 value) internal pure returns (int88 downcasted) {
downcasted = int88(value);
require(downcasted == value, "SafeCast: value doesn't fit in 88 bits");
}
/**
* @dev Returns the downcasted int80 from int256, reverting on
* overflow (when the input is less than smallest int80 or
* greater than largest int80).
*
* Counterpart to Solidity's `int80` operator.
*
* Requirements:
*
* - input must fit into 80 bits
*
* _Available since v4.7._
*/
function toInt80(int256 value) internal pure returns (int80 downcasted) {
downcasted = int80(value);
require(downcasted == value, "SafeCast: value doesn't fit in 80 bits");
}
/**
* @dev Returns the downcasted int72 from int256, reverting on
* overflow (when the input is less than smallest int72 or
* greater than largest int72).
*
* Counterpart to Solidity's `int72` operator.
*
* Requirements:
*
* - input must fit into 72 bits
*
* _Available since v4.7._
*/
function toInt72(int256 value) internal pure returns (int72 downcasted) {
downcasted = int72(value);
require(downcasted == value, "SafeCast: value doesn't fit in 72 bits");
}
/**
* @dev Returns the downcasted int64 from int256, reverting on
* overflow (when the input is less than smallest int64 or
* greater than largest int64).
*
* Counterpart to Solidity's `int64` operator.
*
* Requirements:
*
* - input must fit into 64 bits
*
* _Available since v3.1._
*/
function toInt64(int256 value) internal pure returns (int64 downcasted) {
downcasted = int64(value);
require(downcasted == value, "SafeCast: value doesn't fit in 64 bits");
}
/**
* @dev Returns the downcasted int56 from int256, reverting on
* overflow (when the input is less than smallest int56 or
* greater than largest int56).
*
* Counterpart to Solidity's `int56` operator.
*
* Requirements:
*
* - input must fit into 56 bits
*
* _Available since v4.7._
*/
function toInt56(int256 value) internal pure returns (int56 downcasted) {
downcasted = int56(value);
require(downcasted == value, "SafeCast: value doesn't fit in 56 bits");
}
/**
* @dev Returns the downcasted int48 from int256, reverting on
* overflow (when the input is less than smallest int48 or
* greater than largest int48).
*
* Counterpart to Solidity's `int48` operator.
*
* Requirements:
*
* - input must fit into 48 bits
*
* _Available since v4.7._
*/
function toInt48(int256 value) internal pure returns (int48 downcasted) {
downcasted = int48(value);
require(downcasted == value, "SafeCast: value doesn't fit in 48 bits");
}
/**
* @dev Returns the downcasted int40 from int256, reverting on
* overflow (when the input is less than smallest int40 or
* greater than largest int40).
*
* Counterpart to Solidity's `int40` operator.
*
* Requirements:
*
* - input must fit into 40 bits
*
* _Available since v4.7._
*/
function toInt40(int256 value) internal pure returns (int40 downcasted) {
downcasted = int40(value);
require(downcasted == value, "SafeCast: value doesn't fit in 40 bits");
}
/**
* @dev Returns the downcasted int32 from int256, reverting on
* overflow (when the input is less than smallest int32 or
* greater than largest int32).
*
* Counterpart to Solidity's `int32` operator.
*
* Requirements:
*
* - input must fit into 32 bits
*
* _Available since v3.1._
*/
function toInt32(int256 value) internal pure returns (int32 downcasted) {
downcasted = int32(value);
require(downcasted == value, "SafeCast: value doesn't fit in 32 bits");
}
/**
* @dev Returns the downcasted int24 from int256, reverting on
* overflow (when the input is less than smallest int24 or
* greater than largest int24).
*
* Counterpart to Solidity's `int24` operator.
*
* Requirements:
*
* - input must fit into 24 bits
*
* _Available since v4.7._
*/
function toInt24(int256 value) internal pure returns (int24 downcasted) {
downcasted = int24(value);
require(downcasted == value, "SafeCast: value doesn't fit in 24 bits");
}
/**
* @dev Returns the downcasted int16 from int256, reverting on
* overflow (when the input is less than smallest int16 or
* greater than largest int16).
*
* Counterpart to Solidity's `int16` operator.
*
* Requirements:
*
* - input must fit into 16 bits
*
* _Available since v3.1._
*/
function toInt16(int256 value) internal pure returns (int16 downcasted) {
downcasted = int16(value);
require(downcasted == value, "SafeCast: value doesn't fit in 16 bits");
}
/**
* @dev Returns the downcasted int8 from int256, reverting on
* overflow (when the input is less than smallest int8 or
* greater than largest int8).
*
* Counterpart to Solidity's `int8` operator.
*
* Requirements:
*
* - input must fit into 8 bits
*
* _Available since v3.1._
*/
function toInt8(int256 value) internal pure returns (int8 downcasted) {
downcasted = int8(value);
require(downcasted == value, "SafeCast: value doesn't fit in 8 bits");
}
/**
* @dev Converts an unsigned uint256 into a signed int256.
*
* Requirements:
*
* - input must be less than or equal to maxInt256.
*
* _Available since v3.0._
*/
function toInt256(uint256 value) internal pure returns (int256) {
// Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
return int256(value);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (utils/math/SignedMath.sol)
pragma solidity ^0.8.0;
/**
* @dev Standard signed math utilities missing in the Solidity language.
*/
library SignedMath {
/**
* @dev Returns the largest of two signed numbers.
*/
function max(int256 a, int256 b) internal pure returns (int256) {
return a > b ? a : b;
}
/**
* @dev Returns the smallest of two signed numbers.
*/
function min(int256 a, int256 b) internal pure returns (int256) {
return a < b ? a : b;
}
/**
* @dev Returns the average of two signed numbers without overflow.
* The result is rounded towards zero.
*/
function average(int256 a, int256 b) internal pure returns (int256) {
// Formula from the book "Hacker's Delight"
int256 x = (a & b) + ((a ^ b) >> 1);
return x + (int256(uint256(x) >> 255) & (a ^ b));
}
/**
* @dev Returns the absolute unsigned value of a signed value.
*/
function abs(int256 n) internal pure returns (uint256) {
unchecked {
// must be unchecked in order to support `n = type(int256).min`
return uint256(n >= 0 ? n : -n);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/ShortStrings.sol)
pragma solidity ^0.8.8;
import "./StorageSlot.sol";
// | string | 0xAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA |
// | length | 0x BB |
type ShortString is bytes32;
/**
* @dev This library provides functions to convert short memory strings
* into a `ShortString` type that can be used as an immutable variable.
*
* Strings of arbitrary length can be optimized using this library if
* they are short enough (up to 31 bytes) by packing them with their
* length (1 byte) in a single EVM word (32 bytes). Additionally, a
* fallback mechanism can be used for every other case.
*
* Usage example:
*
* ```solidity
* contract Named {
* using ShortStrings for *;
*
* ShortString private immutable _name;
* string private _nameFallback;
*
* constructor(string memory contractName) {
* _name = contractName.toShortStringWithFallback(_nameFallback);
* }
*
* function name() external view returns (string memory) {
* return _name.toStringWithFallback(_nameFallback);
* }
* }
* ```
*/
library ShortStrings {
// Used as an identifier for strings longer than 31 bytes.
bytes32 private constant _FALLBACK_SENTINEL = 0x00000000000000000000000000000000000000000000000000000000000000FF;
error StringTooLong(string str);
error InvalidShortString();
/**
* @dev Encode a string of at most 31 chars into a `ShortString`.
*
* This will trigger a `StringTooLong` error is the input string is too long.
*/
function toShortString(string memory str) internal pure returns (ShortString) {
bytes memory bstr = bytes(str);
if (bstr.length > 31) {
revert StringTooLong(str);
}
return ShortString.wrap(bytes32(uint256(bytes32(bstr)) | bstr.length));
}
/**
* @dev Decode a `ShortString` back to a "normal" string.
*/
function toString(ShortString sstr) internal pure returns (string memory) {
uint256 len = byteLength(sstr);
// using `new string(len)` would work locally but is not memory safe.
string memory str = new string(32);
/// @solidity memory-safe-assembly
assembly {
mstore(str, len)
mstore(add(str, 0x20), sstr)
}
return str;
}
/**
* @dev Return the length of a `ShortString`.
*/
function byteLength(ShortString sstr) internal pure returns (uint256) {
uint256 result = uint256(ShortString.unwrap(sstr)) & 0xFF;
if (result > 31) {
revert InvalidShortString();
}
return result;
}
/**
* @dev Encode a string into a `ShortString`, or write it to storage if it is too long.
*/
function toShortStringWithFallback(string memory value, string storage store) internal returns (ShortString) {
if (bytes(value).length < 32) {
return toShortString(value);
} else {
StorageSlot.getStringSlot(store).value = value;
return ShortString.wrap(_FALLBACK_SENTINEL);
}
}
/**
* @dev Decode a string that was encoded to `ShortString` or written to storage using {setWithFallback}.
*/
function toStringWithFallback(ShortString value, string storage store) internal pure returns (string memory) {
if (ShortString.unwrap(value) != _FALLBACK_SENTINEL) {
return toString(value);
} else {
return store;
}
}
/**
* @dev Return the length of a string that was encoded to `ShortString` or written to storage using {setWithFallback}.
*
* WARNING: This will return the "byte length" of the string. This may not reflect the actual length in terms of
* actual characters as the UTF-8 encoding of a single character can span over multiple bytes.
*/
function byteLengthWithFallback(ShortString value, string storage store) internal view returns (uint256) {
if (ShortString.unwrap(value) != _FALLBACK_SENTINEL) {
return byteLength(value);
} else {
return bytes(store).length;
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/StorageSlot.sol)
// This file was procedurally generated from scripts/generate/templates/StorageSlot.js.
pragma solidity ^0.8.0;
/**
* @dev Library for reading and writing primitive types to specific storage slots.
*
* Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
* This library helps with reading and writing to such slots without the need for inline assembly.
*
* The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
*
* Example usage to set ERC1967 implementation slot:
* ```solidity
* contract ERC1967 {
* bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
*
* function _getImplementation() internal view returns (address) {
* return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
* }
*
* function _setImplementation(address newImplementation) internal {
* require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
* StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
* }
* }
* ```
*
* _Available since v4.1 for `address`, `bool`, `bytes32`, `uint256`._
* _Available since v4.9 for `string`, `bytes`._
*/
library StorageSlot {
struct AddressSlot {
address value;
}
struct BooleanSlot {
bool value;
}
struct Bytes32Slot {
bytes32 value;
}
struct Uint256Slot {
uint256 value;
}
struct StringSlot {
string value;
}
struct BytesSlot {
bytes value;
}
/**
* @dev Returns an `AddressSlot` with member `value` located at `slot`.
*/
function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `BooleanSlot` with member `value` located at `slot`.
*/
function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
*/
function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `Uint256Slot` with member `value` located at `slot`.
*/
function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `StringSlot` with member `value` located at `slot`.
*/
function getStringSlot(bytes32 slot) internal pure returns (StringSlot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `StringSlot` representation of the string storage pointer `store`.
*/
function getStringSlot(string storage store) internal pure returns (StringSlot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := store.slot
}
}
/**
* @dev Returns an `BytesSlot` with member `value` located at `slot`.
*/
function getBytesSlot(bytes32 slot) internal pure returns (BytesSlot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `BytesSlot` representation of the bytes storage pointer `store`.
*/
function getBytesSlot(bytes storage store) internal pure returns (BytesSlot storage r) {
/// @solidity memory-safe-assembly
assembly {
r.slot := store.slot
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.9.0) (utils/Strings.sol)
pragma solidity ^0.8.0;
import "./math/Math.sol";
import "./math/SignedMath.sol";
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _SYMBOLS = "0123456789abcdef";
uint8 private constant _ADDRESS_LENGTH = 20;
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
unchecked {
uint256 length = Math.log10(value) + 1;
string memory buffer = new string(length);
uint256 ptr;
/// @solidity memory-safe-assembly
assembly {
ptr := add(buffer, add(32, length))
}
while (true) {
ptr--;
/// @solidity memory-safe-assembly
assembly {
mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
}
value /= 10;
if (value == 0) break;
}
return buffer;
}
}
/**
* @dev Converts a `int256` to its ASCII `string` decimal representation.
*/
function toString(int256 value) internal pure returns (string memory) {
return string(abi.encodePacked(value < 0 ? "-" : "", toString(SignedMath.abs(value))));
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
unchecked {
return toHexString(value, Math.log256(value) + 1);
}
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
/**
* @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
*/
function toHexString(address addr) internal pure returns (string memory) {
return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
}
/**
* @dev Returns true if the two strings are equal.
*/
function equal(string memory a, string memory b) internal pure returns (bool) {
return keccak256(bytes(a)) == keccak256(bytes(b));
}
}
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;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.8;
interface ITreasury {
function onSellFeePaid(address from, uint256 amount) external;
function onBuyFeePaid(address from, uint256 amount) external;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.8;
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/extensions/ERC20Burnable.sol";
import "@openzeppelin/contracts/token/ERC20/extensions/ERC20Votes.sol";
import "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
import "@openzeppelin/contracts/utils/introspection/IERC165.sol";
import "@openzeppelin/contracts/governance/utils/IVotes.sol";
import "@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol";
import "@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol";
import "./ITreasury.sol";
/**
* @title SAGE Token Contract
*/
contract SAGE is IERC165, IERC20Metadata, Ownable, ERC20Burnable, ERC20Votes {
/// @notice Emitted when a liquidity pool pair is updated.
event LPPairSet(address indexed pair, bool enabled);
/// @notice Emitted when an account is marked or unmarked as a liquidity holder (treasury, staking, etc).
event LiquidityHolderSet(address indexed account, bool flag);
/// @notice Emitted (once) when fees are locked forever.
event FeesLockedForever();
/// @notice Emitted (once) when sniper bot protection is disabled forever.
event SniperBotProtectionDisabledForever();
event BlacklistSet(address indexed account, bool flag);
/// @notice Emitted (once) when blacklist add is disabled forever.
event BlacklistAddDisabledForever();
/// @notice Emitted (once) when whale protection is disabled forever.
event whaleProtectionDisabledForever();
event BuyFeeNumeratorSet(uint256 value);
event SellFeeNumeratorSet(uint256 value);
event TreasurySet(
address treasuryBuy,
address treasurySell,
bool doCallback
);
event BuyFeePaid(address indexed from, uint256 amount);
event SellFeePaid(address indexed from, uint256 amount);
event IsWhitelisted(address indexed account, uint256 whitelistedAllowance);
/**
* @dev Struct to group account-specific flags to optimize storage usage.
*
* For a deeper understanding of storage packing and its benefits, you can refer to:
* - https://docs.soliditylang.org/en/latest/internals/layout_in_storage.html
* - https://dev.to/web3_ruud/advance-soliditymastering-storage-slot-c38
*/
struct AccountInfo {
bool isLPPool;
bool isLiquidityHolder;
bool isBlackListed;
}
mapping (address => AccountInfo) public accountInfo;
string constant private _name = "SAGE";
string constant private _symbol = "SAGE";
uint256 constant private TOTAL_SUPPLY = 100_000_000 * (10 ** 18);
uint256 constant public DENOMINATOR = 10000;
uint256 constant public MAX_BUY_FEE_NUMERATOR = 500; // 5%
uint256 constant public MAX_SELL_FEE_NUMERATOR = 500; // 5%
uint256 public buyFeeNumerator;
uint256 public _sellFeeNumerator;
address public treasuryBuy;
address public treasurySell;
bool public treasuryDoCallback;
bool public feesAreLockedForever;
bool public sniperBotProtectionDisabledForever;
bool public blacklistAddDisabledForever;
// note: whitelist is active only during the first 10 minutes to prevent sniper bots from buying
mapping (address => uint256) public whitelistedAllowance; // amount how much tokens can he buy
uint256 public presaleStartTime;
uint256 public presaleEndTime;
constructor(
address _treasuryBuy,
address _treasurySell,
bool _treasuryDoCallback,
uint256 _buyFeeNumeratorValue,
uint256 _sellFeeNumeratorValue
) Ownable() ERC20(_name, _symbol) ERC20Permit(_name) payable {
_setLiquidityHolder(msg.sender, true);
_setTreasury(_treasuryBuy, _treasurySell, _treasuryDoCallback);
setBuyFeeNumerator(_buyFeeNumeratorValue);
setSellFeeNumerator(_sellFeeNumeratorValue);
_setSupportedInterface(type(IERC165).interfaceId, true);
_setSupportedInterface(type(IVotes).interfaceId, true);
_mint(address(this), TOTAL_SUPPLY);
_setLiquidityHolder(address(this), true);
_setWhitelistedAllowance(msg.sender, type(uint256).max);
}
function createLP(
IUniswapV2Factory _uniswapV2Factory,
IUniswapV2Router02 _uniswapV2Router
) public onlyOwner payable {
_approve(address(this), address(_uniswapV2Router), TOTAL_SUPPLY);
address WETH = _uniswapV2Router.WETH();
address pair = IUniswapV2Factory(_uniswapV2Factory).createPair(address(this), WETH);
_setLpPair(pair, true);
IUniswapV2Router02(_uniswapV2Router).addLiquidityETH{value: msg.value}({
token: address(this),
amountTokenDesired: TOTAL_SUPPLY,
amountTokenMin: 0,
amountETHMin: 0,
to: msg.sender,
deadline: block.timestamp
});
}
function setPresaleTime(uint256 _startTime, uint256 _endTime) external onlyOwner {
require(presaleStartTime == 0, "Can be set only once");
require(_startTime < _endTime, "Invalid time");
require(_startTime > block.timestamp, "Invalid time");
presaleStartTime = _startTime;
presaleEndTime = _endTime;
}
function setWhitelistedAllowance(address account, uint256 _whitelistedAllowance) external onlyOwner {
_setWhitelistedAllowance(account, _whitelistedAllowance);
}
function whitelistAllowanceMany(address[] calldata accounts, uint256 _whitelistedAllowance) external onlyOwner {
for (uint256 i = 0; i < accounts.length; i++) {
_setWhitelistedAllowance(accounts[i], _whitelistedAllowance);
}
}
function _setWhitelistedAllowance(address account, uint256 _whitelistedAllowance) internal {
whitelistedAllowance[account] = _whitelistedAllowance;
emit IsWhitelisted(account, _whitelistedAllowance);
}
function _checkWhitelistedAllowance(uint256 amount) internal {
require(presaleStartTime != 0, "Presale time is not set");
require(block.timestamp >= presaleStartTime, "Sales are not active yet");
if (block.timestamp > presaleEndTime) {
// no restrictions after the presale
return;
}
// during the presale only whitelisted accounts can buy
uint256 allowance = whitelistedAllowance[tx.origin]; // note: tx.origin is used
require(allowance >= amount, "Whitelisted allowance exceeded");
_setWhitelistedAllowance(tx.origin, allowance - amount);
}
function setTreasury(
address _treasuryBuy,
address _treasurySell,
bool _treasuryDoCallback
) public onlyOwner {
_setTreasury(_treasuryBuy, _treasurySell, _treasuryDoCallback);
}
function _setTreasury(
address _treasuryBuy,
address _treasurySell,
bool _treasuryDoCallback
) internal {
require(_treasuryBuy != address(0), "Treasury address cannot be zero");
require(_treasurySell != address(0), "Treasury address cannot be zero");
treasuryBuy = _treasuryBuy;
treasurySell = _treasurySell;
treasuryDoCallback = _treasuryDoCallback;
emit TreasurySet(_treasuryBuy, _treasurySell, _treasuryDoCallback);
_setLiquidityHolder(_treasuryBuy, true);
_setLiquidityHolder(_treasurySell, true);
}
function lockFeesForever() external onlyOwner {
require(!feesAreLockedForever, "already set");
feesAreLockedForever = true;
emit FeesLockedForever();
}
function disableBlacklistAddForever() external onlyOwner {
require(!blacklistAddDisabledForever, "already set");
blacklistAddDisabledForever = true;
emit BlacklistAddDisabledForever();
}
function setLpPair(address pair, bool enabled) external onlyOwner {
_setLpPair(pair, enabled);
}
function _setLpPair(address pair, bool enabled) internal {
accountInfo[pair].isLPPool = enabled;
emit LPPairSet(pair, enabled);
}
function setBlacklisted(address account, bool isBlacklisted) external onlyOwner {
if (isBlacklisted) {
require(!blacklistAddDisabledForever, "Blacklist add disabled forever");
}
accountInfo[account].isBlackListed = isBlacklisted;
emit BlacklistSet(account, isBlacklisted);
}
function setBuyFeeNumerator(uint256 value) public onlyOwner {
require(!feesAreLockedForever, "Fees are locked forever");
require(value <= MAX_BUY_FEE_NUMERATOR, "Exceeds maximum buy fee");
buyFeeNumerator = value;
emit BuyFeeNumeratorSet(value);
}
function setSellFeeNumerator(uint256 value) public onlyOwner {
require(!feesAreLockedForever, "Fees are locked forever");
require(value <= MAX_SELL_FEE_NUMERATOR, "Exceeds maximum buy fee");
_sellFeeNumerator = value;
emit SellFeeNumeratorSet(value);
}
function sellFeeNumerator() public view returns(uint256) {
if (sniperBotProtectionDisabledForever) {
return _sellFeeNumerator;
}
return DENOMINATOR; // during the first 15minutes after the launch it's 100% to prevent sniper bots from buying
}
function disableSniperBotProtectionForever() external onlyOwner {
require(!sniperBotProtectionDisabledForever, "already set");
sniperBotProtectionDisabledForever = true;
emit SniperBotProtectionDisabledForever();
}
function setLiquidityHolder(address account, bool flag) public onlyOwner {
_setLiquidityHolder(account, flag);
}
function _setLiquidityHolder(address account, bool flag) internal {
accountInfo[account].isLiquidityHolder = flag;
emit LiquidityHolderSet(account, flag);
}
function _hasLimits(AccountInfo memory fromInfo, AccountInfo memory toInfo) internal pure returns(bool) {
return !fromInfo.isLiquidityHolder && !toInfo.isLiquidityHolder;
}
function _transfer(address from, address to, uint256 amount) internal override {
AccountInfo memory fromInfo = accountInfo[from];
AccountInfo memory toInfo = accountInfo[to];
require(!fromInfo.isBlackListed && !toInfo.isBlackListed, "Blacklisted");
if (!_hasLimits(fromInfo, toInfo) ||
(fromInfo.isLPPool && toInfo.isLPPool) // no fee for transferring between pools
) {
super._transfer(from, to, amount);
return;
}
uint256 buyFeeAmount = 0;
uint256 sellFeeAmount = 0;
if (fromInfo.isLPPool) {
// buy
buyFeeAmount = amount * buyFeeNumerator / DENOMINATOR;
super._transfer(from, treasuryBuy, buyFeeAmount);
emit BuyFeePaid(from, buyFeeAmount);
unchecked { // underflow is not possible
amount -= buyFeeAmount;
}
_checkWhitelistedAllowance(amount);
} else if (toInfo.isLPPool) {
// sell
sellFeeAmount = amount * sellFeeNumerator() / DENOMINATOR;
super._transfer(from, treasurySell, sellFeeAmount);
emit SellFeePaid(from, sellFeeAmount);
unchecked { // underflow is not possible
amount -= sellFeeAmount;
}
} else {
// no fees for usual transfers
}
super._transfer(from, to, amount);
if (treasuryDoCallback) {
if (buyFeeAmount > 0) {
ITreasury(treasuryBuy).onBuyFeePaid(from, buyFeeAmount);
}
if (sellFeeAmount > 0) {
ITreasury(treasurySell).onSellFeePaid(from, sellFeeAmount);
}
}
}
function _afterTokenTransfer(address from, address to, uint256 amount) internal override(ERC20, ERC20Votes) {
super._afterTokenTransfer(from, to, amount);
}
function _mint(address account, uint256 amount) internal override(ERC20, ERC20Votes) {
super._mint(account, amount);
}
function _burn(address account, uint256 amount) internal override(ERC20, ERC20Votes) {
super._burn(account, amount);
}
mapping (bytes4 => bool) private _supportedInterfaces;
event InterfaceSupported(bytes4 indexed interfaceId, bool value);
function setSupportedInterface(bytes4 interfaceId, bool value) external onlyOwner {
_setSupportedInterface(interfaceId, value);
}
function _setSupportedInterface(bytes4 interfaceId, bool value) internal {
_supportedInterfaces[interfaceId] = value;
emit InterfaceSupported(interfaceId, value);
}
function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
return _supportedInterfaces[interfaceId];
}
}