A full decompilation and automatic security analysis of all contracts on the Ethereum and the Fantom blockchains. Updated hourly with new contracts uploaded to both networks. Analysis results by Dedaub.

Contract Library by Dedaub

bound

clOracles

oracle

decimal

cloPreferred

base

cloAddress

cloPrice

refPrice

refTimestamp

decimals

infos

price

coeff

spread

isAdmin

isWoFeasible

owner

newPrice

postPrice

bases

newPrices

postPriceList

newSpread

postSpread

newSpreads

postSpreadList

newCoeff

postState

newCoeffs

postStateList

priceOut

feasible

quoteToken

renounceOwnership

addr

flag

setAdmin

_bound

setBound

token

_oracle

_cloPreferred

setCLOracle

setCloPreferred

_quote

setQuoteToken

newStaleDuration

setStaleDuration

staleDuration

state

woFeasible

timestamp

newOwner

transferOwnership

woCoeff

woPrice

priceTimestampOut

woSpread

woState

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)

pragma solidity ^0.8.1;

/**
 * @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
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    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
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

Address.sol

// SPDX-License-Identifier: MIT
pragma solidity =0.8.14;

interface AggregatorV3Interface {
    function decimals() external view returns (uint8);

    function description() external view returns (string memory);

    function version() external view returns (uint256);

    /// getRoundData and latestRoundData should both raise "No data present"
    /// if they do not have data to report, instead of returning unset values
    /// which could be misinterpreted as actual reported values.
    function getRoundData(uint80 _roundId)
        external
        view
        returns (
            uint80 roundId,
            int256 answer,
            uint256 startedAt,
            uint256 updatedAt,
            uint80 answeredInRound
        );

    function latestRoundData()
        external
        view
        returns (
            uint80 roundId,
            int256 answer,
            uint256 startedAt,
            uint256 updatedAt,
            uint80 answeredInRound
        );
}

AggregatorV3Interface.sol

// 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;
    }
}

Context.sol

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (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);
}

IERC20.sol

// SPDX-License-Identifier: MIT
pragma solidity =0.8.14;

/*

░██╗░░░░░░░██╗░█████╗░░█████╗░░░░░░░███████╗██╗
░██║░░██╗░░██║██╔══██╗██╔══██╗░░░░░░██╔════╝██║
░╚██╗████╗██╔╝██║░░██║██║░░██║█████╗█████╗░░██║
░░████╔═████║░██║░░██║██║░░██║╚════╝██╔══╝░░██║
░░╚██╔╝░╚██╔╝░╚█████╔╝╚█████╔╝░░░░░░██║░░░░░██║
░░░╚═╝░░░╚═╝░░░╚════╝░░╚════╝░░░░░░░╚═╝░░░░░╚═╝

*
* MIT License
* ===========
*
* Copyright (c) 2020 WooTrade
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

/// @title The oracle V2 interface by Woo.Network.
/// @notice update and posted the latest price info by Woo.
interface IWooracleV2 {
    struct State {
        uint128 price;
        uint64 spread;
        uint64 coeff;
        bool woFeasible;
    }

    /// @notice Wooracle spread value
    function woSpread(address base) external view returns (uint64);

    /// @notice Wooracle coeff value
    function woCoeff(address base) external view returns (uint64);

    /// @notice Wooracle state for the specified base token
    function woState(address base) external view returns (State memory);

    /// @notice Chainlink oracle address for the specified base token
    function cloAddress(address base) external view returns (address clo);

    /// @notice ChainLink price of the base token / quote token
    function cloPrice(address base) external view returns (uint256 price, uint256 timestamp);

    /// @notice Wooracle price of the base token
    function woPrice(address base) external view returns (uint128 price, uint256 timestamp);

    /// @notice Returns Woooracle price if available, otherwise fallback to ChainLink
    function price(address base) external view returns (uint256 priceNow, bool feasible);

    /// @notice Updates the Wooracle price for the specified base token
    function postPrice(address base, uint128 newPrice) external;

    /// @notice State of the specified base token.
    function state(address base) external view returns (State memory);

    /// @notice The price decimal for the specified base token (e.g. 8)
    function decimals(address base) external view returns (uint8);

    /// @notice The quote token for calculating WooPP query price
    function quoteToken() external view returns (address);

    /// @notice last updated timestamp
    function timestamp() external view returns (uint256);

    /// @notice Flag for Wooracle price feasible
    function isWoFeasible(address base) external view returns (bool);
}

IWooracleV2.sol

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
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 anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    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);
    }
}

Ownable.sol

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)

pragma solidity ^0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor() {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}

ReentrancyGuard.sol

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (token/ERC20/utils/SafeERC20.sol)

pragma solidity ^0.8.0;

import "IERC20.sol";
import "draft-IERC20Permit.sol";
import "Address.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));
        }
    }

    function safePermit(
        IERC20Permit token,
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) internal {
        uint256 nonceBefore = token.nonces(owner);
        token.permit(owner, spender, value, deadline, v, r, s);
        uint256 nonceAfter = token.nonces(owner);
        require(nonceAfter == nonceBefore + 1, "SafeERC20: permit did not succeed");
    }

    /**
     * @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");
        }
    }
}

SafeERC20.sol

// SPDX-License-Identifier: MIT
pragma solidity =0.8.14;

/*

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*
* MIT License
* ===========
*
* Copyright (c) 2020 WooTrade
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

import "IWooracleV2.sol";
import "AggregatorV3Interface.sol";

// OpenZeppelin contracts
import {Ownable} from "Ownable.sol";
import {ReentrancyGuard} from "ReentrancyGuard.sol";
import {IERC20, SafeERC20} from "SafeERC20.sol";

/// @title Wooracle V2 contract
contract WooracleV2 is Ownable, IWooracleV2 {
    /* ----- State variables ----- */

    // 128 + 64 + 64 = 256 bits (slot size)
    struct TokenInfo {
        uint128 price; // as chainlink oracle (e.g. decimal = 8)
        uint64 coeff; // k: decimal = 18.    18.4 * 1e18
        uint64 spread; // s: decimal = 18.   spread <= 2e18   18.4 * 1e18
    }

    struct CLOracle {
        address oracle;
        uint8 decimal;
        bool cloPreferred;
    }

    mapping(address => TokenInfo) public infos;

    mapping(address => CLOracle) public clOracles;

    address public override quoteToken;
    uint256 public override timestamp;

    uint256 public staleDuration;
    uint64 public bound;

    mapping(address => bool) public isAdmin;

    constructor() {
        staleDuration = uint256(300);
        bound = uint64(1e16); // 1%
    }

    modifier onlyAdmin() {
        require(owner() == msg.sender || isAdmin[msg.sender], "Wooracle: !Admin");
        _;
    }

    /* ----- External Functions ----- */

    function setAdmin(address addr, bool flag) external onlyOwner {
        isAdmin[addr] = flag;
    }

    /// @dev Set the quote token address.
    /// @param _oracle the token address
    function setQuoteToken(address _quote, address _oracle) external onlyAdmin {
        quoteToken = _quote;
        CLOracle storage cloRef = clOracles[_quote];
        cloRef.oracle = _oracle;
        cloRef.decimal = AggregatorV3Interface(_oracle).decimals();
    }

    function setBound(uint64 _bound) external onlyOwner {
        bound = _bound;
    }

    function setCLOracle(
        address token,
        address _oracle,
        bool _cloPreferred
    ) external onlyAdmin {
        CLOracle storage cloRef = clOracles[token];
        cloRef.oracle = _oracle;
        cloRef.decimal = AggregatorV3Interface(_oracle).decimals();
        cloRef.cloPreferred = _cloPreferred;
    }

    function setCloPreferred(address token, bool _cloPreferred) external onlyAdmin {
        CLOracle storage cloRef = clOracles[token];
        cloRef.cloPreferred = _cloPreferred;
    }

    /// @dev Set the staleDuration.
    /// @param newStaleDuration the new stale duration
    function setStaleDuration(uint256 newStaleDuration) external onlyAdmin {
        staleDuration = newStaleDuration;
    }

    /// @dev Update the base token prices.
    /// @param base the baseToken address
    /// @param newPrice the new prices for the base token
    function postPrice(address base, uint128 newPrice) external override onlyAdmin {
        infos[base].price = newPrice;
        timestamp = block.timestamp;
    }

    /// @dev batch update baseTokens prices
    /// @param bases list of baseToken address
    /// @param newPrices the updated prices list
    function postPriceList(address[] calldata bases, uint128[] calldata newPrices) external onlyAdmin {
        uint256 length = bases.length;
        require(length == newPrices.length, "Wooracle: length_INVALID");

        // TODO: gas optimization:
        // https://ethereum.stackexchange.com/questions/113221/what-is-the-purpose-of-unchecked-in-solidity
        // https://forum.openzeppelin.com/t/a-collection-of-gas-optimisation-tricks/19966
        unchecked {
            for (uint256 i = 0; i < length; i++) {
                infos[bases[i]].price = newPrices[i];
            }
        }

        timestamp = block.timestamp;
    }

    /// @dev update the spreads info.
    /// @param base baseToken address
    /// @param newSpread the new spreads
    function postSpread(address base, uint64 newSpread) external onlyAdmin {
        infos[base].spread = newSpread;
        timestamp = block.timestamp;
    }

    /// @dev batch update the spreads info.
    /// @param bases list of baseToken address
    /// @param newSpreads list of spreads info
    function postSpreadList(address[] calldata bases, uint64[] calldata newSpreads) external onlyAdmin {
        uint256 length = bases.length;
        require(length == newSpreads.length, "Wooracle: length_INVALID");

        unchecked {
            for (uint256 i = 0; i < length; i++) {
                infos[bases[i]].spread = newSpreads[i];
            }
        }

        timestamp = block.timestamp;
    }

    /// @dev update the state of the given base token.
    /// @param base baseToken address
    /// @param newPrice the new prices
    /// @param newSpread the new spreads
    /// @param newCoeff the new slippage coefficent
    function postState(
        address base,
        uint128 newPrice,
        uint64 newSpread,
        uint64 newCoeff
    ) external onlyAdmin {
        _setState(base, newPrice, newSpread, newCoeff);
        timestamp = block.timestamp;
    }

    /// @dev batch update the prices, spreads and slipagge coeffs info.
    /// @param bases list of baseToken address
    /// @param newPrices the prices list
    /// @param newSpreads the spreads list
    /// @param newCoeffs the slippage coefficent list
    function postStateList(
        address[] calldata bases,
        uint128[] calldata newPrices,
        uint64[] calldata newSpreads,
        uint64[] calldata newCoeffs
    ) external onlyAdmin {
        uint256 length = bases.length;
        unchecked {
            for (uint256 i = 0; i < length; i++) {
                _setState(bases[i], newPrices[i], newSpreads[i], newCoeffs[i]);
            }
        }
        timestamp = block.timestamp;
    }

    /*
        Price logic:
        - woPrice: wooracle price
        - cloPrice: chainlink price

        woFeasible is, price > 0 and price timestamp NOT stale

        when woFeasible && priceWithinBound     -> woPrice, feasible
        when woFeasible && !priceWithinBound    -> woPrice, infeasible
        when !woFeasible && clo_preferred       -> cloPrice, feasible
        when !woFeasible && !clo_preferred      -> cloPrice, infeasible
    */
    function price(address base) public view override returns (uint256 priceOut, bool feasible) {
        uint256 woPrice_ = uint256(infos[base].price);
        uint256 woPriceTimestamp = timestamp;

        (uint256 cloPrice_, ) = _cloPriceInQuote(base, quoteToken);

        bool woFeasible = woPrice_ != 0 && block.timestamp <= (woPriceTimestamp + staleDuration);
        bool woPriceInBound = cloPrice_ == 0 ||
            ((cloPrice_ * (1e18 - bound)) / 1e18 <= woPrice_ && woPrice_ <= (cloPrice_ * (1e18 + bound)) / 1e18);

        if (woFeasible) {
            priceOut = woPrice_;
            feasible = woPriceInBound;
        } else {
            priceOut = clOracles[base].cloPreferred ? cloPrice_ : 0;
            feasible = priceOut != 0;
        }
    }

    /// @notice the price decimal for the specified base token
    function decimals(address base) external view override returns (uint8) {
        uint8 d = clOracles[base].decimal;
        return d != 0 ? d : 8;
    }

    function cloPrice(address base) external view override returns (uint256 refPrice, uint256 refTimestamp) {
        return _cloPriceInQuote(base, quoteToken);
    }

    function isWoFeasible(address base) external view override returns (bool) {
        return infos[base].price != 0 && block.timestamp <= (timestamp + staleDuration);
    }

    function woSpread(address base) external view override returns (uint64) {
        return infos[base].spread;
    }

    function woCoeff(address base) external view override returns (uint64) {
        return infos[base].coeff;
    }

    // Wooracle price of the base token
    function woPrice(address base) external view override returns (uint128 priceOut, uint256 priceTimestampOut) {
        priceOut = infos[base].price;
        priceTimestampOut = timestamp;
    }

    function woState(address base) external view override returns (State memory) {
        TokenInfo memory info = infos[base];
        return
            State({
                price: info.price,
                spread: info.spread,
                coeff: info.coeff,
                woFeasible: (info.price != 0 && block.timestamp <= (timestamp + staleDuration))
            });
    }

    function state(address base) external view override returns (State memory) {
        TokenInfo memory info = infos[base];
        (uint256 basePrice, bool feasible) = price(base);
        return State({price: uint128(basePrice), spread: info.spread, coeff: info.coeff, woFeasible: feasible});
    }

    function cloAddress(address base) external view override returns (address clo) {
        clo = clOracles[base].oracle;
    }

    /* ----- Private Functions ----- */
    function _setState(
        address base,
        uint128 newPrice,
        uint64 newSpread,
        uint64 newCoeff
    ) private {
        TokenInfo storage info = infos[base];
        info.price = newPrice;
        info.spread = newSpread;
        info.coeff = newCoeff;
    }

    function _cloPriceInQuote(address fromToken, address toToken)
        private
        view
        returns (uint256 refPrice, uint256 refTimestamp)
    {
        address baseOracle = clOracles[fromToken].oracle;
        if (baseOracle == address(0)) {
            return (0, 0);
        }
        address quoteOracle = clOracles[toToken].oracle;
        uint8 quoteDecimal = clOracles[toToken].decimal;

        (, int256 rawBaseRefPrice, , uint256 baseUpdatedAt, ) = AggregatorV3Interface(baseOracle).latestRoundData();
        (, int256 rawQuoteRefPrice, , uint256 quoteUpdatedAt, ) = AggregatorV3Interface(quoteOracle).latestRoundData();
        uint256 baseRefPrice = uint256(rawBaseRefPrice);
        uint256 quoteRefPrice = uint256(rawQuoteRefPrice);

        // NOTE: Assume wooracle token decimal is same as chainlink token decimal.
        uint256 ceoff = uint256(10)**quoteDecimal;
        refPrice = (baseRefPrice * ceoff) / quoteRefPrice;
        refTimestamp = baseUpdatedAt >= quoteUpdatedAt ? quoteUpdatedAt : baseUpdatedAt;
    }
}

WooracleV2.sol

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-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);
}

draft-IERC20Permit.sol

__ANONYMOUS__