Contract Name:
DesignatedVotingV2
Contract Source Code:
File 1 of 1 : DesignatedVotingV2
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity 0.8.16;
// File @openzeppelin/contracts/token/ERC20/[email protected]
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @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 `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, 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 `sender` to `recipient` 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 sender,
address recipient,
uint256 amount
) external returns (bool);
/**
* @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);
}
// File @openzeppelin/contracts/token/ERC20/extensions/[email protected]
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.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);
}
// File @openzeppelin/contracts/utils/[email protected]
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
/**
* @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;
}
}
// File @openzeppelin/contracts/token/ERC20/[email protected]
// OpenZeppelin Contracts v4.4.1 (token/ERC20/ERC20.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.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* 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}.
*
* The default value of {decimals} is 18. To select a different value for
* {decimals} you should overload it.
*
* 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 value {ERC20} uses, unless this function is
* 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:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
_transfer(_msgSender(), recipient, 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}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 amount) public virtual override returns (bool) {
_approve(_msgSender(), 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}.
*
* Requirements:
*
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
* - the caller must have allowance for ``sender``'s tokens of at least
* `amount`.
*/
function transferFrom(
address sender,
address recipient,
uint256 amount
) public virtual override returns (bool) {
_transfer(sender, recipient, amount);
uint256 currentAllowance = _allowances[sender][_msgSender()];
require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
unchecked {
_approve(sender, _msgSender(), currentAllowance - 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) {
_approve(_msgSender(), spender, _allowances[_msgSender()][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) {
uint256 currentAllowance = _allowances[_msgSender()][spender];
require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
unchecked {
_approve(_msgSender(), spender, currentAllowance - subtractedValue);
}
return true;
}
/**
* @dev Moves `amount` of tokens from `sender` to `recipient`.
*
* 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:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(
address sender,
address recipient,
uint256 amount
) internal virtual {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_beforeTokenTransfer(sender, recipient, amount);
uint256 senderBalance = _balances[sender];
require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
unchecked {
_balances[sender] = senderBalance - amount;
}
_balances[recipient] += amount;
emit Transfer(sender, recipient, amount);
_afterTokenTransfer(sender, recipient, 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;
_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;
}
_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 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 {}
}
// File @openzeppelin/contracts/utils/math/[email protected]
// OpenZeppelin Contracts v4.4.1 (utils/math/Math.sol)
/**
* @dev Standard math utilities missing in the Solidity language.
*/
library Math {
/**
* @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 / b + (a % b == 0 ? 0 : 1);
}
}
// File @openzeppelin/contracts/utils/[email protected]
// OpenZeppelin Contracts v4.4.1 (utils/Arrays.sol)
/**
* @dev Collection of functions related to array types.
*/
library Arrays {
/**
* @dev Searches a sorted `array` and returns the first index that contains
* a value greater or equal to `element`. If no such index exists (i.e. all
* values in the array are strictly less than `element`), the array length is
* returned. Time complexity O(log n).
*
* `array` is expected to be sorted in ascending order, and to contain no
* repeated elements.
*/
function findUpperBound(uint256[] storage array, uint256 element) internal view returns (uint256) {
if (array.length == 0) {
return 0;
}
uint256 low = 0;
uint256 high = array.length;
while (low < high) {
uint256 mid = Math.average(low, high);
// Note that mid will always be strictly less than high (i.e. it will be a valid array index)
// because Math.average rounds down (it does integer division with truncation).
if (array[mid] > element) {
high = mid;
} else {
low = mid + 1;
}
}
// At this point `low` is the exclusive upper bound. We will return the inclusive upper bound.
if (low > 0 && array[low - 1] == element) {
return low - 1;
} else {
return low;
}
}
}
// File @openzeppelin/contracts/utils/[email protected]
// OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
/**
* @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;
}
}
// File @openzeppelin/contracts/token/ERC20/extensions/[email protected]
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/ERC20Snapshot.sol)
/**
* @dev This contract extends an ERC20 token with a snapshot mechanism. When a snapshot is created, the balances and
* total supply at the time are recorded for later access.
*
* This can be used to safely create mechanisms based on token balances such as trustless dividends or weighted voting.
* In naive implementations it's possible to perform a "double spend" attack by reusing the same balance from different
* accounts. By using snapshots to calculate dividends or voting power, those attacks no longer apply. It can also be
* used to create an efficient ERC20 forking mechanism.
*
* Snapshots are created by the internal {_snapshot} function, which will emit the {Snapshot} event and return a
* snapshot id. To get the total supply at the time of a snapshot, call the function {totalSupplyAt} with the snapshot
* id. To get the balance of an account at the time of a snapshot, call the {balanceOfAt} function with the snapshot id
* and the account address.
*
* NOTE: Snapshot policy can be customized by overriding the {_getCurrentSnapshotId} method. For example, having it
* return `block.number` will trigger the creation of snapshot at the begining of each new block. When overridding this
* function, be careful about the monotonicity of its result. Non-monotonic snapshot ids will break the contract.
*
* Implementing snapshots for every block using this method will incur significant gas costs. For a gas-efficient
* alternative consider {ERC20Votes}.
*
* ==== Gas Costs
*
* Snapshots are efficient. Snapshot creation is _O(1)_. Retrieval of balances or total supply from a snapshot is _O(log
* n)_ in the number of snapshots that have been created, although _n_ for a specific account will generally be much
* smaller since identical balances in subsequent snapshots are stored as a single entry.
*
* There is a constant overhead for normal ERC20 transfers due to the additional snapshot bookkeeping. This overhead is
* only significant for the first transfer that immediately follows a snapshot for a particular account. Subsequent
* transfers will have normal cost until the next snapshot, and so on.
*/
abstract contract ERC20Snapshot is ERC20 {
// Inspired by Jordi Baylina's MiniMeToken to record historical balances:
// https://github.com/Giveth/minimd/blob/ea04d950eea153a04c51fa510b068b9dded390cb/contracts/MiniMeToken.sol
using Arrays for uint256[];
using Counters for Counters.Counter;
// Snapshotted values have arrays of ids and the value corresponding to that id. These could be an array of a
// Snapshot struct, but that would impede usage of functions that work on an array.
struct Snapshots {
uint256[] ids;
uint256[] values;
}
mapping(address => Snapshots) private _accountBalanceSnapshots;
Snapshots private _totalSupplySnapshots;
// Snapshot ids increase monotonically, with the first value being 1. An id of 0 is invalid.
Counters.Counter private _currentSnapshotId;
/**
* @dev Emitted by {_snapshot} when a snapshot identified by `id` is created.
*/
event Snapshot(uint256 id);
/**
* @dev Creates a new snapshot and returns its snapshot id.
*
* Emits a {Snapshot} event that contains the same id.
*
* {_snapshot} is `internal` and you have to decide how to expose it externally. Its usage may be restricted to a
* set of accounts, for example using {AccessControl}, or it may be open to the public.
*
* [WARNING]
* ====
* While an open way of calling {_snapshot} is required for certain trust minimization mechanisms such as forking,
* you must consider that it can potentially be used by attackers in two ways.
*
* First, it can be used to increase the cost of retrieval of values from snapshots, although it will grow
* logarithmically thus rendering this attack ineffective in the long term. Second, it can be used to target
* specific accounts and increase the cost of ERC20 transfers for them, in the ways specified in the Gas Costs
* section above.
*
* We haven't measured the actual numbers; if this is something you're interested in please reach out to us.
* ====
*/
function _snapshot() internal virtual returns (uint256) {
_currentSnapshotId.increment();
uint256 currentId = _getCurrentSnapshotId();
emit Snapshot(currentId);
return currentId;
}
/**
* @dev Get the current snapshotId
*/
function _getCurrentSnapshotId() internal view virtual returns (uint256) {
return _currentSnapshotId.current();
}
/**
* @dev Retrieves the balance of `account` at the time `snapshotId` was created.
*/
function balanceOfAt(address account, uint256 snapshotId) public view virtual returns (uint256) {
(bool snapshotted, uint256 value) = _valueAt(snapshotId, _accountBalanceSnapshots[account]);
return snapshotted ? value : balanceOf(account);
}
/**
* @dev Retrieves the total supply at the time `snapshotId` was created.
*/
function totalSupplyAt(uint256 snapshotId) public view virtual returns (uint256) {
(bool snapshotted, uint256 value) = _valueAt(snapshotId, _totalSupplySnapshots);
return snapshotted ? value : totalSupply();
}
// Update balance and/or total supply snapshots before the values are modified. This is implemented
// in the _beforeTokenTransfer hook, which is executed for _mint, _burn, and _transfer operations.
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual override {
super._beforeTokenTransfer(from, to, amount);
if (from == address(0)) {
// mint
_updateAccountSnapshot(to);
_updateTotalSupplySnapshot();
} else if (to == address(0)) {
// burn
_updateAccountSnapshot(from);
_updateTotalSupplySnapshot();
} else {
// transfer
_updateAccountSnapshot(from);
_updateAccountSnapshot(to);
}
}
function _valueAt(uint256 snapshotId, Snapshots storage snapshots) private view returns (bool, uint256) {
require(snapshotId > 0, "ERC20Snapshot: id is 0");
require(snapshotId <= _getCurrentSnapshotId(), "ERC20Snapshot: nonexistent id");
// When a valid snapshot is queried, there are three possibilities:
// a) The queried value was not modified after the snapshot was taken. Therefore, a snapshot entry was never
// created for this id, and all stored snapshot ids are smaller than the requested one. The value that corresponds
// to this id is the current one.
// b) The queried value was modified after the snapshot was taken. Therefore, there will be an entry with the
// requested id, and its value is the one to return.
// c) More snapshots were created after the requested one, and the queried value was later modified. There will be
// no entry for the requested id: the value that corresponds to it is that of the smallest snapshot id that is
// larger than the requested one.
//
// In summary, we need to find an element in an array, returning the index of the smallest value that is larger if
// it is not found, unless said value doesn't exist (e.g. when all values are smaller). Arrays.findUpperBound does
// exactly this.
uint256 index = snapshots.ids.findUpperBound(snapshotId);
if (index == snapshots.ids.length) {
return (false, 0);
} else {
return (true, snapshots.values[index]);
}
}
function _updateAccountSnapshot(address account) private {
_updateSnapshot(_accountBalanceSnapshots[account], balanceOf(account));
}
function _updateTotalSupplySnapshot() private {
_updateSnapshot(_totalSupplySnapshots, totalSupply());
}
function _updateSnapshot(Snapshots storage snapshots, uint256 currentValue) private {
uint256 currentId = _getCurrentSnapshotId();
if (_lastSnapshotId(snapshots.ids) < currentId) {
snapshots.ids.push(currentId);
snapshots.values.push(currentValue);
}
}
function _lastSnapshotId(uint256[] storage ids) private view returns (uint256) {
if (ids.length == 0) {
return 0;
} else {
return ids[ids.length - 1];
}
}
}
// File @openzeppelin/contracts/utils/[email protected]
// OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize, which returns 0 for contracts in
// construction, since the code is only stored at the end of the
// constructor execution.
uint256 size;
assembly {
size := extcodesize(account)
}
return size > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// File @openzeppelin/contracts/token/ERC20/utils/[email protected]
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
function safeTransfer(
IERC20 token,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(
IERC20 token,
address from,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(
IERC20 token,
address spender,
uint256 value
) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
"SafeERC20: approve from non-zero to non-zero allowance"
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
function safeDecreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
if (returndata.length > 0) {
// Return data is optional
require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
}
}
}
// File contracts/common/implementation/MultiRole.sol
library Exclusive {
struct RoleMembership {
address member;
}
function isMember(RoleMembership storage roleMembership, address memberToCheck) internal view returns (bool) {
return roleMembership.member == memberToCheck;
}
function resetMember(RoleMembership storage roleMembership, address newMember) internal {
require(newMember != address(0x0), "Cannot set an exclusive role to 0x0");
roleMembership.member = newMember;
}
function getMember(RoleMembership storage roleMembership) internal view returns (address) {
return roleMembership.member;
}
function init(RoleMembership storage roleMembership, address initialMember) internal {
resetMember(roleMembership, initialMember);
}
}
library Shared {
struct RoleMembership {
mapping(address => bool) members;
}
function isMember(RoleMembership storage roleMembership, address memberToCheck) internal view returns (bool) {
return roleMembership.members[memberToCheck];
}
function addMember(RoleMembership storage roleMembership, address memberToAdd) internal {
require(memberToAdd != address(0x0), "Cannot add 0x0 to a shared role");
roleMembership.members[memberToAdd] = true;
}
function removeMember(RoleMembership storage roleMembership, address memberToRemove) internal {
roleMembership.members[memberToRemove] = false;
}
function init(RoleMembership storage roleMembership, address[] memory initialMembers) internal {
for (uint256 i = 0; i < initialMembers.length; i++) {
addMember(roleMembership, initialMembers[i]);
}
}
}
/**
* @title Base class to manage permissions for the derived class.
*/
abstract contract MultiRole {
using Exclusive for Exclusive.RoleMembership;
using Shared for Shared.RoleMembership;
enum RoleType { Invalid, Exclusive, Shared }
struct Role {
uint256 managingRole;
RoleType roleType;
Exclusive.RoleMembership exclusiveRoleMembership;
Shared.RoleMembership sharedRoleMembership;
}
mapping(uint256 => Role) private roles;
event ResetExclusiveMember(uint256 indexed roleId, address indexed newMember, address indexed manager);
event AddedSharedMember(uint256 indexed roleId, address indexed newMember, address indexed manager);
event RemovedSharedMember(uint256 indexed roleId, address indexed oldMember, address indexed manager);
/**
* @notice Reverts unless the caller is a member of the specified roleId.
*/
modifier onlyRoleHolder(uint256 roleId) {
require(holdsRole(roleId, msg.sender), "Sender does not hold required role");
_;
}
/**
* @notice Reverts unless the caller is a member of the manager role for the specified roleId.
*/
modifier onlyRoleManager(uint256 roleId) {
require(holdsRole(roles[roleId].managingRole, msg.sender), "Can only be called by a role manager");
_;
}
/**
* @notice Reverts unless the roleId represents an initialized, exclusive roleId.
*/
modifier onlyExclusive(uint256 roleId) {
require(roles[roleId].roleType == RoleType.Exclusive, "Must be called on an initialized Exclusive role");
_;
}
/**
* @notice Reverts unless the roleId represents an initialized, shared roleId.
*/
modifier onlyShared(uint256 roleId) {
require(roles[roleId].roleType == RoleType.Shared, "Must be called on an initialized Shared role");
_;
}
/**
* @notice Whether `memberToCheck` is a member of roleId.
* @dev Reverts if roleId does not correspond to an initialized role.
* @param roleId the Role to check.
* @param memberToCheck the address to check.
* @return True if `memberToCheck` is a member of `roleId`.
*/
function holdsRole(uint256 roleId, address memberToCheck) public view returns (bool) {
Role storage role = roles[roleId];
if (role.roleType == RoleType.Exclusive) {
return role.exclusiveRoleMembership.isMember(memberToCheck);
} else if (role.roleType == RoleType.Shared) {
return role.sharedRoleMembership.isMember(memberToCheck);
}
revert("Invalid roleId");
}
/**
* @notice Changes the exclusive role holder of `roleId` to `newMember`.
* @dev Reverts if the caller is not a member of the managing role for `roleId` or if `roleId` is not an
* initialized, ExclusiveRole.
* @param roleId the ExclusiveRole membership to modify.
* @param newMember the new ExclusiveRole member.
*/
function resetMember(uint256 roleId, address newMember) public onlyExclusive(roleId) onlyRoleManager(roleId) {
roles[roleId].exclusiveRoleMembership.resetMember(newMember);
emit ResetExclusiveMember(roleId, newMember, msg.sender);
}
/**
* @notice Gets the current holder of the exclusive role, `roleId`.
* @dev Reverts if `roleId` does not represent an initialized, exclusive role.
* @param roleId the ExclusiveRole membership to check.
* @return the address of the current ExclusiveRole member.
*/
function getMember(uint256 roleId) public view onlyExclusive(roleId) returns (address) {
return roles[roleId].exclusiveRoleMembership.getMember();
}
/**
* @notice Adds `newMember` to the shared role, `roleId`.
* @dev Reverts if `roleId` does not represent an initialized, SharedRole or if the caller is not a member of the
* managing role for `roleId`.
* @param roleId the SharedRole membership to modify.
* @param newMember the new SharedRole member.
*/
function addMember(uint256 roleId, address newMember) public onlyShared(roleId) onlyRoleManager(roleId) {
roles[roleId].sharedRoleMembership.addMember(newMember);
emit AddedSharedMember(roleId, newMember, msg.sender);
}
/**
* @notice Removes `memberToRemove` from the shared role, `roleId`.
* @dev Reverts if `roleId` does not represent an initialized, SharedRole or if the caller is not a member of the
* managing role for `roleId`.
* @param roleId the SharedRole membership to modify.
* @param memberToRemove the current SharedRole member to remove.
*/
function removeMember(uint256 roleId, address memberToRemove) public onlyShared(roleId) onlyRoleManager(roleId) {
roles[roleId].sharedRoleMembership.removeMember(memberToRemove);
emit RemovedSharedMember(roleId, memberToRemove, msg.sender);
}
/**
* @notice Removes caller from the role, `roleId`.
* @dev Reverts if the caller is not a member of the role for `roleId` or if `roleId` is not an
* initialized, SharedRole.
* @param roleId the SharedRole membership to modify.
*/
function renounceMembership(uint256 roleId) public onlyShared(roleId) onlyRoleHolder(roleId) {
roles[roleId].sharedRoleMembership.removeMember(msg.sender);
emit RemovedSharedMember(roleId, msg.sender, msg.sender);
}
/**
* @notice Reverts if `roleId` is not initialized.
*/
modifier onlyValidRole(uint256 roleId) {
require(roles[roleId].roleType != RoleType.Invalid, "Attempted to use an invalid roleId");
_;
}
/**
* @notice Reverts if `roleId` is initialized.
*/
modifier onlyInvalidRole(uint256 roleId) {
require(roles[roleId].roleType == RoleType.Invalid, "Cannot use a pre-existing role");
_;
}
/**
* @notice Internal method to initialize a shared role, `roleId`, which will be managed by `managingRoleId`.
* `initialMembers` will be immediately added to the role.
* @dev Should be called by derived contracts, usually at construction time. Will revert if the role is already
* initialized.
*/
function _createSharedRole(
uint256 roleId,
uint256 managingRoleId,
address[] memory initialMembers
) internal onlyInvalidRole(roleId) {
Role storage role = roles[roleId];
role.roleType = RoleType.Shared;
role.managingRole = managingRoleId;
role.sharedRoleMembership.init(initialMembers);
require(
roles[managingRoleId].roleType != RoleType.Invalid,
"Attempted to use an invalid role to manage a shared role"
);
}
/**
* @notice Internal method to initialize an exclusive role, `roleId`, which will be managed by `managingRoleId`.
* `initialMember` will be immediately added to the role.
* @dev Should be called by derived contracts, usually at construction time. Will revert if the role is already
* initialized.
*/
function _createExclusiveRole(
uint256 roleId,
uint256 managingRoleId,
address initialMember
) internal onlyInvalidRole(roleId) {
Role storage role = roles[roleId];
role.roleType = RoleType.Exclusive;
role.managingRole = managingRoleId;
role.exclusiveRoleMembership.init(initialMember);
require(
roles[managingRoleId].roleType != RoleType.Invalid,
"Attempted to use an invalid role to manage an exclusive role"
);
}
}
// File contracts/common/interfaces/ExpandedIERC20.sol
/**
* @title ERC20 interface that includes burn and mint methods.
*/
abstract contract ExpandedIERC20 is IERC20 {
/**
* @notice Burns a specific amount of the caller's tokens.
* @dev Only burns the caller's tokens, so it is safe to leave this method permissionless.
*/
function burn(uint256 value) external virtual;
/**
* @dev Burns `value` tokens owned by `recipient`.
* @param recipient address to burn tokens from.
* @param value amount of tokens to burn.
*/
function burnFrom(address recipient, uint256 value) external virtual returns (bool);
/**
* @notice Mints tokens and adds them to the balance of the `to` address.
* @dev This method should be permissioned to only allow designated parties to mint tokens.
*/
function mint(address to, uint256 value) external virtual returns (bool);
function addMinter(address account) external virtual;
function addBurner(address account) external virtual;
function resetOwner(address account) external virtual;
}
// File contracts/common/implementation/ExpandedERC20.sol
/**
* @title An ERC20 with permissioned burning and minting. The contract deployer will initially
* be the owner who is capable of adding new roles.
*/
contract ExpandedERC20 is ExpandedIERC20, ERC20, MultiRole {
enum Roles {
// Can set the minter and burner.
Owner,
// Addresses that can mint new tokens.
Minter,
// Addresses that can burn tokens that address owns.
Burner
}
uint8 _decimals;
/**
* @notice Constructs the ExpandedERC20.
* @param _tokenName The name which describes the new token.
* @param _tokenSymbol The ticker abbreviation of the name. Ideally < 5 chars.
* @param _tokenDecimals The number of decimals to define token precision.
*/
constructor(
string memory _tokenName,
string memory _tokenSymbol,
uint8 _tokenDecimals
) ERC20(_tokenName, _tokenSymbol) {
_decimals = _tokenDecimals;
_createExclusiveRole(uint256(Roles.Owner), uint256(Roles.Owner), msg.sender);
_createSharedRole(uint256(Roles.Minter), uint256(Roles.Owner), new address[](0));
_createSharedRole(uint256(Roles.Burner), uint256(Roles.Owner), new address[](0));
}
function decimals() public view virtual override(ERC20) returns (uint8) {
return _decimals;
}
/**
* @dev Mints `value` tokens to `recipient`, returning true on success.
* @param recipient address to mint to.
* @param value amount of tokens to mint.
* @return True if the mint succeeded, or False.
*/
function mint(address recipient, uint256 value)
external
override
onlyRoleHolder(uint256(Roles.Minter))
returns (bool)
{
_mint(recipient, value);
return true;
}
/**
* @dev Burns `value` tokens owned by `msg.sender`.
* @param value amount of tokens to burn.
*/
function burn(uint256 value) external override onlyRoleHolder(uint256(Roles.Burner)) {
_burn(msg.sender, value);
}
/**
* @dev Burns `value` tokens owned by `recipient`.
* @param recipient address to burn tokens from.
* @param value amount of tokens to burn.
* @return True if the burn succeeded, or False.
*/
function burnFrom(address recipient, uint256 value)
external
override
onlyRoleHolder(uint256(Roles.Burner))
returns (bool)
{
_burn(recipient, value);
return true;
}
/**
* @notice Add Minter role to account.
* @dev The caller must have the Owner role.
* @param account The address to which the Minter role is added.
*/
function addMinter(address account) external virtual override {
addMember(uint256(Roles.Minter), account);
}
/**
* @notice Add Burner role to account.
* @dev The caller must have the Owner role.
* @param account The address to which the Burner role is added.
*/
function addBurner(address account) external virtual override {
addMember(uint256(Roles.Burner), account);
}
/**
* @notice Reset Owner role to account.
* @dev The caller must have the Owner role.
* @param account The new holder of the Owner role.
*/
function resetOwner(address account) external virtual override {
resetMember(uint256(Roles.Owner), account);
}
}
// File contracts/common/implementation/Withdrawable.sol
/**
* Withdrawable contract.
*/
/**
* @title Base contract that allows a specific role to withdraw any ETH and/or ERC20 tokens that the contract holds.
*/
abstract contract Withdrawable is MultiRole {
using SafeERC20 for IERC20;
uint256 private roleId;
/**
* @notice Withdraws ETH from the contract.
*/
function withdraw(uint256 amount) external onlyRoleHolder(roleId) {
Address.sendValue(payable(msg.sender), amount);
}
/**
* @notice Withdraws ERC20 tokens from the contract.
* @param erc20Address ERC20 token to withdraw.
* @param amount amount of tokens to withdraw.
*/
function withdrawErc20(address erc20Address, uint256 amount) external onlyRoleHolder(roleId) {
IERC20 erc20 = IERC20(erc20Address);
erc20.safeTransfer(msg.sender, amount);
}
/**
* @notice Internal method that allows derived contracts to create a role for withdrawal.
* @dev Either this method or `_setWithdrawRole` must be called by the derived class for this contract to function
* properly.
* @param newRoleId ID corresponding to role whose members can withdraw.
* @param managingRoleId ID corresponding to managing role who can modify the withdrawable role's membership.
* @param withdrawerAddress new manager of withdrawable role.
*/
function _createWithdrawRole(
uint256 newRoleId,
uint256 managingRoleId,
address withdrawerAddress
) internal {
roleId = newRoleId;
_createExclusiveRole(newRoleId, managingRoleId, withdrawerAddress);
}
/**
* @notice Internal method that allows derived contracts to choose the role for withdrawal.
* @dev The role `setRoleId` must exist. Either this method or `_createWithdrawRole` must be
* called by the derived class for this contract to function properly.
* @param setRoleId ID corresponding to role whose members can withdraw.
*/
function _setWithdrawRole(uint256 setRoleId) internal onlyValidRole(setRoleId) {
roleId = setRoleId;
}
}
// File contracts/data-verification-mechanism/implementation/VotingToken.sol
/**
* @title Ownership of this token allows a voter to respond to price requests.
* @dev Supports snapshotting and allows the Oracle to mint new tokens as rewards.
*/
contract VotingToken is ExpandedERC20, ERC20Snapshot {
/**
* @notice Constructs the VotingToken.
*/
constructor() ExpandedERC20("UMA Voting Token v1", "UMA", 18) ERC20Snapshot() {}
function decimals() public view virtual override(ERC20, ExpandedERC20) returns (uint8) {
return super.decimals();
}
/**
* @notice Creates a new snapshot ID.
* @return uint256 Thew new snapshot ID.
*/
function snapshot() external returns (uint256) {
return _snapshot();
}
// _transfer, _mint and _burn are ERC20 internal methods that are overridden by ERC20Snapshot,
// therefore the compiler will complain that VotingToken must override these methods
// because the two base classes (ERC20 and ERC20Snapshot) both define the same functions
function _transfer(
address from,
address to,
uint256 value
) internal override(ERC20) {
super._transfer(from, to, value);
}
function _mint(address account, uint256 value) internal virtual override(ERC20) {
super._mint(account, value);
}
function _burn(address account, uint256 value) internal virtual override(ERC20) {
super._burn(account, value);
}
function _beforeTokenTransfer(
address from,
address to,
uint256 amount
) internal virtual override(ERC20, ERC20Snapshot) {
super._beforeTokenTransfer(from, to, amount);
}
}
// File contracts/data-verification-mechanism/interfaces/StakerInterface.sol
interface StakerInterface {
function votingToken() external returns (ExpandedIERC20);
function stake(uint128 amount) external;
function requestUnstake(uint128 amount) external;
function executeUnstake() external;
function withdrawRewards() external returns (uint128);
function withdrawAndRestake() external returns (uint128);
function setEmissionRate(uint128 newEmissionRate) external;
function setUnstakeCoolDown(uint64 newUnstakeCoolDown) external;
/**
* @notice Sets the delegate of a voter. This delegate can vote on behalf of the staker. The staker will still own
* all staked balances, receive rewards and be slashed based on the actions of the delegate. Intended use is using a
* low-security available wallet for voting while keeping access to staked amounts secure by a more secure wallet.
* @param delegate the address of the delegate.
*/
function setDelegate(address delegate) external virtual;
/**
* @notice Sets the delegator of a voter. Acts to accept a delegation. The delegate can only vote for the delegator
* if the delegator also selected the delegate to do so (two-way relationship needed).
* @param delegator the address of the delegator.
*/
function setDelegator(address delegator) external virtual;
}
// File contracts/common/implementation/Stakeable.sol
/**
* Stakeable contract.
*/
/**
* @title Base contract that extends the Withdrawable contract enabling a specific role to stake ERC20 tokens against the
* Voting contract. Voting contract is fed in as a param rather than fetched from the finder to enable upgradability.
*/
abstract contract Stakeable is Withdrawable {
using SafeERC20 for IERC20;
uint256 private roleId;
/**
* @notice Stake ERC20 tokens from this contract to the votingContract.
* @param amount amount of tokens to stake.
* @param votingContract Address of the voting contract to stake into.
*/
function stake(uint128 amount, address votingContract) external onlyRoleHolder(roleId) {
StakerInterface voting = StakerInterface(votingContract);
IERC20 votingToken = IERC20(voting.votingToken());
votingToken.approve(votingContract, amount);
voting.stake(amount);
}
/**
* @notice Request unstaking of ERC20 tokens from this contract to the votingContract.
* @param amount amount of tokens to unstake.
* @param votingContract Address of the voting contract to unstake from.
*/
function requestUnstake(uint128 amount, address votingContract) external onlyRoleHolder(roleId) {
StakerInterface voting = StakerInterface(votingContract);
voting.requestUnstake(amount);
}
/**
* @notice Execute an unstake request that has passed liveness on the voting contract.
* @param votingContract Address of the voting contract to execute the unstake from.
*/
function executeUnstake(address votingContract) external onlyRoleHolder(roleId) {
StakerInterface voting = StakerInterface(votingContract);
voting.executeUnstake();
}
/**
* @notice Internal method that allows derived contracts to choose the role for stakeable.
* @dev The role `setRoleId` must exist. Either this method or `_setStakeRole` must be
* called by the derived class for this contract to function properly.
* @param setRoleId ID corresponding to role whose members can stakeable.
*/
function _setStakeRole(uint256 setRoleId) internal onlyValidRole(setRoleId) {
roleId = setRoleId;
}
}
// File contracts/common/implementation/MultiCaller.sol
// This contract is taken from Uniswap's multi call implementation (https://github.com/Uniswap/uniswap-v3-periphery/blob/main/contracts/base/Multicall.sol)
// and was modified to be solidity 0.8 compatible. Additionally, the method was restricted to only work with msg.value
// set to 0 to avoid any nasty attack vectors on function calls that use value sent with deposits.
/// @title MultiCaller
/// @notice Enables calling multiple methods in a single call to the contract
contract MultiCaller {
function multicall(bytes[] calldata data) external returns (bytes[] memory results) {
results = new bytes[](data.length);
for (uint256 i = 0; i < data.length; i++) {
(bool success, bytes memory result) = address(this).delegatecall(data[i]);
if (!success) {
// Next 5 lines from https://ethereum.stackexchange.com/a/83577
if (result.length < 68) revert();
assembly {
result := add(result, 0x04)
}
revert(abi.decode(result, (string)));
}
results[i] = result;
}
}
}
// File contracts/data-verification-mechanism/implementation/Constants.sol
/**
* @title Stores common interface names used throughout the DVM by registration in the Finder.
*/
library OracleInterfaces {
bytes32 public constant Oracle = "Oracle";
bytes32 public constant IdentifierWhitelist = "IdentifierWhitelist";
bytes32 public constant Store = "Store";
bytes32 public constant FinancialContractsAdmin = "FinancialContractsAdmin";
bytes32 public constant Registry = "Registry";
bytes32 public constant CollateralWhitelist = "CollateralWhitelist";
bytes32 public constant OptimisticOracle = "OptimisticOracle";
bytes32 public constant OptimisticOracleV2 = "OptimisticOracleV2";
bytes32 public constant Bridge = "Bridge";
bytes32 public constant GenericHandler = "GenericHandler";
bytes32 public constant SkinnyOptimisticOracle = "SkinnyOptimisticOracle";
bytes32 public constant ChildMessenger = "ChildMessenger";
bytes32 public constant OracleHub = "OracleHub";
bytes32 public constant OracleSpoke = "OracleSpoke";
bytes32 public constant OptimisticOracleV3 = "OptimisticOracleV3";
}
/**
* @title Commonly re-used values for contracts associated with the OptimisticOracle.
*/
library OptimisticOracleConstraints {
// Any price request submitted to the OptimisticOracle must contain ancillary data no larger than this value.
// This value must be <= the Voting contract's `ancillaryBytesLimit` constant value otherwise it is possible
// that a price can be requested to the OptimisticOracle successfully, but cannot be resolved by the DVM which
// refuses to accept a price request made with ancillary data length over a certain size.
uint256 public constant ancillaryBytesLimit = 8192;
}
// File contracts/data-verification-mechanism/interfaces/FinderInterface.sol
/**
* @title Provides addresses of the live contracts implementing certain interfaces.
* @dev Examples are the Oracle or Store interfaces.
*/
interface FinderInterface {
/**
* @notice Updates the address of the contract that implements `interfaceName`.
* @param interfaceName bytes32 encoding of the interface name that is either changed or registered.
* @param implementationAddress address of the deployed contract that implements the interface.
*/
function changeImplementationAddress(bytes32 interfaceName, address implementationAddress) external;
/**
* @notice Gets the address of the contract that implements the given `interfaceName`.
* @param interfaceName queried interface.
* @return implementationAddress address of the deployed contract that implements the interface.
*/
function getImplementationAddress(bytes32 interfaceName) external view returns (address);
}
// File contracts/data-verification-mechanism/implementation/DesignatedVotingV2.sol
/**
* @title Proxy to allow voting from another address.
* @dev Allows a UMA token holder to designate another address to vote on their behalf.
* Each voter must deploy their own instance of this contract.
*/
contract DesignatedVotingV2 is Stakeable, MultiCaller {
/****************************************
* INTERNAL VARIABLES AND STORAGE *
****************************************/
enum Roles {
Owner, // Can set the Voter role.
Voter // Can vote through this contract.
}
// Reference to UMA Finder contract, allowing Voting upgrades to be without requiring any calls to this contract.
FinderInterface public immutable finder;
/**
* @notice Construct the DesignatedVotingV2 contract.
* @param finderAddress keeps track of all contracts within the system based on their interfaceName.
* @param ownerAddress address of the owner of the DesignatedVotingV2 contract.
* @param voterAddress address to which the owner has delegated their voting power.
*/
constructor(
address finderAddress,
address ownerAddress,
address voterAddress
) {
_createExclusiveRole(uint256(Roles.Owner), uint256(Roles.Owner), ownerAddress);
_createExclusiveRole(uint256(Roles.Voter), uint256(Roles.Owner), voterAddress);
_setWithdrawRole(uint256(Roles.Owner));
_setStakeRole(uint256(Roles.Owner));
finder = FinderInterface(finderAddress);
}
/**
* @notice This method essentially syncs the voter role with the current voting delegate.
* @dev Because this is essentially a state sync method, there is no reason to restrict its permissioning.
*/
function delegateToVoter() public {
address voter = getMember(uint256(Roles.Voter));
_getVotingContract().setDelegate(voter);
}
// Returns the Voting contract address, named "Oracle" in the finder.
function _getVotingContract() private view returns (StakerInterface) {
return StakerInterface(finder.getImplementationAddress(OracleInterfaces.Oracle));
}
}