Contract

Contract Source Code (Solidity Standard Json-Input format)

IDE

• Blockscan IDE
• 🤖 Code ReaderBeta

More Options

• Similar
• Submit Audit
• Compare

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "./otokens/ONative.sol";
import "@openzeppelin/contracts/utils/Address.sol";

/**
 * @title 0VIX's Maximillion Contract
 * @author 0VIX
 */
contract Maximillion {
    /**
     * @notice The default oNative market to repay in
     */
    ONative public immutable oNative;

    /**
     * @notice Construct a Maximillion to repay max in a ONative market
     */
    constructor(ONative oNative_) {
        oNative = oNative_;
    }

    /**
     * @notice msg.sender sends Native to repay an account's borrow in the oNative market
     * @dev The provided Native is applied towards the borrow balance, any excess is refunded
     * @param borrower The address of the borrower account to repay on behalf of
     */
    function repayBehalf(address borrower) public payable {
        repayBehalfExplicit(borrower, oNative);
    }

    /**
     * @notice msg.sender sends Native to repay an account's borrow in a oNative market
     * @dev The provided Native is applied towards the borrow balance, any excess is refunded
     * @param borrower The address of the borrower account to repay on behalf of
     * @param oNative_ The address of the oNative contract to repay in
     */
    function repayBehalfExplicit(address borrower, ONative oNative_) public payable {
        uint received = msg.value;
        uint borrows = oNative_.borrowBalanceCurrent(borrower);
        if (received > borrows) {
            oNative_.repayBorrowBehalf{value: borrows}(borrower);
            Address.sendValue(payable(msg.sender), received - borrows);
        } else {
            oNative_.repayBorrowBehalf{value: received}(borrower);
        }
    }
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @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 `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);

    /**
     * @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);
}

// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (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

                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

/**
  * @title 0VIX's IInterestRateModel Interface
  * @author 0VIX
  */
interface IInterestRateModel {
    /// @notice Indicator that this is an InterestRateModel contract (for inspection)
    function isInterestRateModel() external view returns(bool);

    /**
      * @notice Calculates the current borrow interest rate per timestmp
      * @param cash The total amount of cash the market has
      * @param borrows The total amount of borrows the market has outstanding
      * @param reserves The total amount of reserves the market has
      * @return The borrow rate per timestmp (as a percentage, and scaled by 1e18)
      */
    function getBorrowRate(uint cash, uint borrows, uint reserves) external view returns (uint);

    /**
      * @notice Calculates the current supply interest rate per timestmp
      * @param cash The total amount of cash the market has
      * @param borrows The total amount of borrows the market has outstanding
      * @param reserves The total amount of reserves the market has
      * @param reserveFactorMantissa The current reserve factor the market has
      * @return The supply rate per timestmp (as a percentage, and scaled by 1e18)
      */
    function getSupplyRate(uint cash, uint borrows, uint reserves, uint reserveFactorMantissa) external view returns (uint);

}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "../otokens/interfaces/IOToken.sol";
import "../PriceOracle.sol";

interface IComptroller {
    /// @notice Indicator that this is a Comptroller contract (for inspection)
    function isComptroller() external view returns(bool);

    /*** Assets You Are In ***/

    function enterMarkets(address[] calldata oTokens) external returns (uint[] memory);
    function exitMarket(address oToken) external returns (uint);

    /*** Policy Hooks ***/

    function mintAllowed(address oToken, address minter, uint mintAmount) external returns (uint);
    function mintVerify(address oToken, address minter, uint mintAmount, uint mintTokens) external;

    function redeemAllowed(address oToken, address redeemer, uint redeemTokens) external returns (uint);
    function redeemVerify(address oToken, address redeemer, uint redeemAmount, uint redeemTokens) external;

    function borrowAllowed(address oToken, address borrower, uint borrowAmount) external returns (uint);
    function borrowVerify(address oToken, address borrower, uint borrowAmount) external;

    function repayBorrowAllowed(
        address oToken,
        address payer,
        address borrower,
        uint repayAmount) external returns (uint);

    function liquidateBorrowAllowed(
        address oTokenBorrowed,
        address oTokenCollateral,
        address liquidator,
        address borrower,
        uint repayAmount) external returns (uint);

    function seizeAllowed(
        address oTokenCollateral,
        address oTokenBorrowed,
        address liquidator,
        address borrower,
        uint seizeTokens) external returns (uint);
        
    function seizeVerify(
        address oTokenCollateral,
        address oTokenBorrowed,
        address liquidator,
        address borrower,
        uint seizeTokens) external;

    function transferAllowed(address oToken, address src, address dst, uint transferTokens) external returns (uint);
    function transferVerify(address oToken, address src, address dst, uint transferTokens) external;

    /*** Liquidity/Liquidation Calculations ***/

    function liquidateCalculateSeizeTokens(
        address oTokenBorrowed,
        address oTokenCollateral,
        uint repayAmount) external view returns (uint, uint);



    function isMarket(address market) external view returns(bool);
    function getBoostManager() external view returns(address);
    function getAllMarkets() external view returns(IOToken[] memory);
    function oracle() external view returns(PriceOracle);

    function updateAndDistributeSupplierRewardsForToken(
        address oToken,
        address account
    ) external;

    function updateAndDistributeBorrowerRewardsForToken(
        address oToken,
        address borrower
    ) external;

    function _setRewardSpeeds(
        address[] memory oTokens,
        uint256[] memory supplySpeeds,
        uint256[] memory borrowSpeeds
    ) external;
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

/**
  * @title Careful Math
  * @author 0VIX
  * @notice Derived from OpenZeppelin's SafeMath library
  *         https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/math/SafeMath.sol
  */
contract CarefulMath {

    /**
     * @dev Possible error codes that we can return
     */
    enum MathError {
        NO_ERROR,
        DIVISION_BY_ZERO,
        INTEGER_OVERFLOW,
        INTEGER_UNDERFLOW
    }

    /**
    * @dev Multiplies two numbers, returns an error on overflow.
    */
    function mulUInt(uint a, uint b) internal pure returns (MathError, uint) {
        unchecked {
            if (a == 0) {
                return (MathError.NO_ERROR, 0);
            }

            uint c = a * b;

            if (c / a != b) {
                return (MathError.INTEGER_OVERFLOW, 0);
            } else {
                return (MathError.NO_ERROR, c);
            }
        }
    }

    /**
    * @dev Integer division of two numbers, truncating the quotient.
    */
    function divUInt(uint a, uint b) internal pure returns (MathError, uint) {
        unchecked {
            if (b == 0) {
                return (MathError.DIVISION_BY_ZERO, 0);
            }

            return (MathError.NO_ERROR, a / b);
        }
    }

    /**
    * @dev Subtracts two numbers, returns an error on overflow (i.e. if subtrahend is greater than minuend).
    */
    function subUInt(uint a, uint b) internal pure returns (MathError, uint) {
        unchecked {
            if (b <= a) {
                return (MathError.NO_ERROR, a - b);
            } else {
                return (MathError.INTEGER_UNDERFLOW, 0);
            }
        }
    }

    /**
    * @dev Adds two numbers, returns an error on overflow.
    */
    function addUInt(uint a, uint b) internal pure returns (MathError, uint) {
        unchecked {
            uint c = a + b;

            if (c >= a) {
                return (MathError.NO_ERROR, c);
            } else {
                return (MathError.INTEGER_OVERFLOW, 0);
            }
        }
    }

    /**
    * @dev add a and b and then subtract c
    */
    function addThenSubUInt(uint a, uint b, uint c) internal pure returns (MathError, uint) {
        (MathError err0, uint sum) = addUInt(a, b);

        if (err0 != MathError.NO_ERROR) {
            return (err0, 0);
        }

        return subUInt(sum, c);
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

contract ComptrollerErrorReporter {
    enum Error {
        NO_ERROR,
        UNAUTHORIZED,
        COMPTROLLER_MISMATCH,
        INSUFFICIENT_SHORTFALL,
        INSUFFICIENT_LIQUIDITY,
        INVALID_CLOSE_FACTOR,
        INVALID_COLLATERAL_FACTOR,
        INVALID_LIQUIDATION_INCENTIVE,
        MARKET_NOT_ENTERED, // no longer possible
        MARKET_NOT_LISTED,
        MARKET_ALREADY_LISTED,
        MATH_ERROR,
        NONZERO_BORROW_BALANCE,
        PRICE_ERROR,
        REJECTION,
        SNAPSHOT_ERROR,
        TOO_MANY_ASSETS,
        TOO_MUCH_REPAY
    }

    enum FailureInfo {
        ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
        ACCEPT_PENDING_IMPLEMENTATION_ADDRESS_CHECK,
        EXIT_MARKET_BALANCE_OWED,
        EXIT_MARKET_REJECTION,
        SET_CLOSE_FACTOR_OWNER_CHECK,
        SET_CLOSE_FACTOR_VALIDATION,
        SET_COLLATERAL_FACTOR_OWNER_CHECK,
        SET_COLLATERAL_FACTOR_NO_EXISTS,
        SET_COLLATERAL_FACTOR_VALIDATION,
        SET_COLLATERAL_FACTOR_WITHOUT_PRICE,
        SET_IMPLEMENTATION_OWNER_CHECK,
        SET_LIQUIDATION_INCENTIVE_OWNER_CHECK,
        SET_LIQUIDATION_INCENTIVE_VALIDATION,
        SET_MAX_ASSETS_OWNER_CHECK,
        SET_PENDING_ADMIN_OWNER_CHECK,
        SET_PENDING_IMPLEMENTATION_OWNER_CHECK,
        SET_PRICE_ORACLE_OWNER_CHECK,
        SUPPORT_MARKET_EXISTS,
        SUPPORT_MARKET_OWNER_CHECK,
        SET_PAUSE_GUARDIAN_OWNER_CHECK
    }

    /**
      * @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary
      * contract-specific code that enables us to report opaque error codes from upgradeable contracts.
      **/
    event Failure(uint error, uint info, uint detail);

    /**
      * @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
      */
    function fail(Error err, FailureInfo info) internal returns (uint) {
        emit Failure(uint(err), uint(info), 0);

        return uint(err);
    }

    /**
      * @dev use this when reporting an opaque error from an upgradeable collaborator contract
      */
    function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
        emit Failure(uint(err), uint(info), opaqueError);

        return uint(err);
    }
}

contract TokenErrorReporter {
    enum Error {
        NO_ERROR,
        UNAUTHORIZED,
        BAD_INPUT,
        COMPTROLLER_REJECTION,
        COMPTROLLER_CALCULATION_ERROR,
        INTEREST_RATE_MODEL_ERROR,
        INVALID_ACCOUNT_PAIR,
        INVALID_CLOSE_AMOUNT_REQUESTED,
        INVALID_COLLATERAL_FACTOR,
        MATH_ERROR,
        MARKET_NOT_FRESH,
        MARKET_NOT_LISTED,
        TOKEN_INSUFFICIENT_ALLOWANCE,
        TOKEN_INSUFFICIENT_BALANCE,
        TOKEN_INSUFFICIENT_CASH,
        TOKEN_TRANSFER_IN_FAILED,
        TOKEN_TRANSFER_OUT_FAILED
    }

    /*
     * Note: FailureInfo (but not Error) is kept in alphabetical order
     *       This is because FailureInfo grows significantly faster, and
     *       the order of Error has some meaning, while the order of FailureInfo
     *       is entirely arbitrary.
     */
    enum FailureInfo {
        ACCEPT_ADMIN_PENDING_ADMIN_CHECK,
        ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED,
        ACCRUE_INTEREST_BORROW_RATE_CALCULATION_FAILED,
        ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED,
        ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED,
        ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED,
        ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED,
        BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
        BORROW_ACCRUE_INTEREST_FAILED,
        BORROW_CASH_NOT_AVAILABLE,
        BORROW_FRESHNESS_CHECK,
        BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
        BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
        BORROW_MARKET_NOT_LISTED,
        BORROW_COMPTROLLER_REJECTION,
        LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED,
        LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED,
        LIQUIDATE_COLLATERAL_FRESHNESS_CHECK,
        LIQUIDATE_COMPTROLLER_REJECTION,
        LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED,
        LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX,
        LIQUIDATE_CLOSE_AMOUNT_IS_ZERO,
        LIQUIDATE_FRESHNESS_CHECK,
        LIQUIDATE_LIQUIDATOR_IS_BORROWER,
        LIQUIDATE_REPAY_BORROW_FRESH_FAILED,
        LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED,
        LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED,
        LIQUIDATE_SEIZE_COMPTROLLER_REJECTION,
        LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER,
        LIQUIDATE_SEIZE_TOO_MUCH,
        MINT_ACCRUE_INTEREST_FAILED,
        MINT_COMPTROLLER_REJECTION,
        MINT_EXCHANGE_CALCULATION_FAILED,
        MINT_EXCHANGE_RATE_READ_FAILED,
        MINT_FRESHNESS_CHECK,
        MINT_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
        MINT_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
        MINT_TRANSFER_IN_FAILED,
        MINT_TRANSFER_IN_NOT_POSSIBLE,
        REDEEM_ACCRUE_INTEREST_FAILED,
        REDEEM_COMPTROLLER_REJECTION,
        REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
        REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED,
        REDEEM_EXCHANGE_RATE_READ_FAILED,
        REDEEM_FRESHNESS_CHECK,
        REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
        REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
        REDEEM_TRANSFER_OUT_NOT_POSSIBLE,
        REDUCE_RESERVES_ACCRUE_INTEREST_FAILED,
        REDUCE_RESERVES_ADMIN_CHECK,
        REDUCE_RESERVES_CASH_NOT_AVAILABLE,
        REDUCE_RESERVES_FRESH_CHECK,
        REDUCE_RESERVES_VALIDATION,
        REPAY_BEHALF_ACCRUE_INTEREST_FAILED,
        REPAY_BORROW_ACCRUE_INTEREST_FAILED,
        REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
        REPAY_BORROW_COMPTROLLER_REJECTION,
        REPAY_BORROW_FRESHNESS_CHECK,
        REPAY_BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
        REPAY_BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
        REPAY_BORROW_TRANSFER_IN_NOT_POSSIBLE,
        SET_COLLATERAL_FACTOR_OWNER_CHECK,
        SET_COLLATERAL_FACTOR_VALIDATION,
        SET_COMPTROLLER_OWNER_CHECK,
        SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED,
        SET_INTEREST_RATE_MODEL_FRESH_CHECK,
        SET_INTEREST_RATE_MODEL_OWNER_CHECK,
        SET_MAX_ASSETS_OWNER_CHECK,
        SET_ORACLE_MARKET_NOT_LISTED,
        SET_PENDING_ADMIN_OWNER_CHECK,
        SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED,
        SET_RESERVE_FACTOR_ADMIN_CHECK,
        SET_RESERVE_FACTOR_FRESH_CHECK,
        SET_RESERVE_FACTOR_BOUNDS_CHECK,
        TRANSFER_COMPTROLLER_REJECTION,
        TRANSFER_NOT_ALLOWED,
        TRANSFER_NOT_ENOUGH,
        TRANSFER_TOO_MUCH,
        ADD_RESERVES_ACCRUE_INTEREST_FAILED,
        ADD_RESERVES_FRESH_CHECK,
        ADD_RESERVES_TRANSFER_IN_NOT_POSSIBLE,
        SET_PROTOCOL_SEIZE_SHARE_ACCRUE_INTEREST_FAILED,
        SET_PROTOCOL_SEIZE_SHARE_OWNER_CHECK,
        SET_PROTOCOL_SEIZE_SHARE_FRESH_CHECK
    }

    /**
      * @dev `error` corresponds to enum Error; `info` corresponds to enum FailureInfo, and `detail` is an arbitrary
      * contract-specific code that enables us to report opaque error codes from upgradeable contracts.
      **/
    event Failure(uint error, uint info, uint detail);

    /**
      * @dev use this when reporting a known error from the money market or a non-upgradeable collaborator
      */
    function fail(Error err, FailureInfo info) internal returns (uint) {
        emit Failure(uint(err), uint(info), 0);

        return uint(err);
    }

    /**
      * @dev use this when reporting an opaque error from an upgradeable collaborator contract
      */
    function failOpaque(Error err, FailureInfo info, uint opaqueError) internal returns (uint) {
        emit Failure(uint(err), uint(info), opaqueError);

        return uint(err);
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "./CarefulMath.sol";
import "./ExponentialNoError.sol";

/**
 * @title Exponential module for storing fixed-precision decimals
 * @author 0VIX
 * @dev Legacy contract for compatibility reasons with existing contracts that still use MathError
 * @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
 *         Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
 *         `Exp({mantissa: 5100000000000000000})`.
 */
contract Exponential is CarefulMath, ExponentialNoError {
    /**
     * @dev Creates an exponential from numerator and denominator values.
     *      Note: Returns an error if (`num` * 10e18) > MAX_INT,
     *            or if `denom` is zero.
     */
    function getExp(uint num, uint denom) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint scaledNumerator) = mulUInt(num, expScale);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        (MathError err1, uint rational) = divUInt(scaledNumerator, denom);
        if (err1 != MathError.NO_ERROR) {
            return (err1, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: rational}));
    }

    /**
     * @dev Adds two exponentials, returning a new exponential.
     */
    function addExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
        (MathError error, uint result) = addUInt(a.mantissa, b.mantissa);

        return (error, Exp({mantissa: result}));
    }

    /**
     * @dev Subtracts two exponentials, returning a new exponential.
     */
    function subExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
        (MathError error, uint result) = subUInt(a.mantissa, b.mantissa);

        return (error, Exp({mantissa: result}));
    }

    /**
     * @dev Multiply an Exp by a scalar, returning a new Exp.
     */
    function mulScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint scaledMantissa) = mulUInt(a.mantissa, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: scaledMantissa}));
    }

    /**
     * @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
     */
    function mulScalarTruncate(Exp memory a, uint scalar) pure internal returns (MathError, uint) {
        (MathError err, Exp memory product) = mulScalar(a, scalar);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return (MathError.NO_ERROR, truncate(product));
    }

    /**
     * @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
     */
    function mulScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (MathError, uint) {
        (MathError err, Exp memory product) = mulScalar(a, scalar);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return addUInt(truncate(product), addend);
    }

    /**
     * @dev Divide an Exp by a scalar, returning a new Exp.
     */
    function divScalar(Exp memory a, uint scalar) pure internal returns (MathError, Exp memory) {
        (MathError err0, uint descaledMantissa) = divUInt(a.mantissa, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        return (MathError.NO_ERROR, Exp({mantissa: descaledMantissa}));
    }

    /**
     * @dev Divide a scalar by an Exp, returning a new Exp.
     */
    function divScalarByExp(uint scalar, Exp memory divisor) pure internal returns (MathError, Exp memory) {
        /*
          We are doing this as:
          getExp(mulUInt(expScale, scalar), divisor.mantissa)

          How it works:
          Exp = a / b;
          Scalar = s;
          `s / (a / b)` = `b * s / a` and since for an Exp `a = mantissa, b = expScale`
        */
        (MathError err0, uint numerator) = mulUInt(expScale, scalar);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }
        return getExp(numerator, divisor.mantissa);
    }

    /**
     * @dev Divide a scalar by an Exp, then truncate to return an unsigned integer.
     */
    function divScalarByExpTruncate(uint scalar, Exp memory divisor) pure internal returns (MathError, uint) {
        (MathError err, Exp memory fraction) = divScalarByExp(scalar, divisor);
        if (err != MathError.NO_ERROR) {
            return (err, 0);
        }

        return (MathError.NO_ERROR, truncate(fraction));
    }

    /**
     * @dev Multiplies two exponentials, returning a new exponential.
     */
    function mulExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {

        (MathError err0, uint doubleScaledProduct) = mulUInt(a.mantissa, b.mantissa);
        if (err0 != MathError.NO_ERROR) {
            return (err0, Exp({mantissa: 0}));
        }

        // We add half the scale before dividing so that we get rounding instead of truncation.
        //  See "Listing 6" and text above it at https://accu.org/index.php/journals/1717
        // Without this change, a result like 6.6...e-19 will be truncated to 0 instead of being rounded to 1e-18.
        (MathError err1, uint doubleScaledProductWithHalfScale) = addUInt(halfExpScale, doubleScaledProduct);
        if (err1 != MathError.NO_ERROR) {
            return (err1, Exp({mantissa: 0}));
        }

        (MathError err2, uint product) = divUInt(doubleScaledProductWithHalfScale, expScale);
        // The only error `div` can return is MathError.DIVISION_BY_ZERO but we control `expScale` and it is not zero.
        assert(err2 == MathError.NO_ERROR);

        return (MathError.NO_ERROR, Exp({mantissa: product}));
    }

    /**
     * @dev Multiplies two exponentials given their mantissas, returning a new exponential.
     */
    function mulExp(uint a, uint b) pure internal returns (MathError, Exp memory) {
        return mulExp(Exp({mantissa: a}), Exp({mantissa: b}));
    }

    /**
     * @dev Multiplies three exponentials, returning a new exponential.
     */
    function mulExp3(Exp memory a, Exp memory b, Exp memory c) pure internal returns (MathError, Exp memory) {
        (MathError err, Exp memory ab) = mulExp(a, b);
        if (err != MathError.NO_ERROR) {
            return (err, ab);
        }
        return mulExp(ab, c);
    }

    /**
     * @dev Divides two exponentials, returning a new exponential.
     *     (a/scale) / (b/scale) = (a/scale) * (scale/b) = a/b,
     *  which we can scale as an Exp by calling getExp(a.mantissa, b.mantissa)
     */
    function divExp(Exp memory a, Exp memory b) pure internal returns (MathError, Exp memory) {
        return getExp(a.mantissa, b.mantissa);
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

/**
 * @title Exponential module for storing fixed-precision decimals
 * @author 0VIX
 * @notice Exp is a struct which stores decimals with a fixed precision of 18 decimal places.
 *         Thus, if we wanted to store the 5.1, mantissa would store 5.1e18. That is:
 *         `Exp({mantissa: 5100000000000000000})`.
 */
contract ExponentialNoError {
    uint constant expScale = 1e18;
    uint constant doubleScale = 1e36;
    uint constant halfExpScale = expScale/2;
    uint constant mantissaOne = expScale;

    struct Exp {
        uint mantissa;
    }

    struct Double {
        uint mantissa;
    }

    /**
     * @dev Truncates the given exp to a whole number value.
     *      For example, truncate(Exp{mantissa: 15 * expScale}) = 15
     */
    function truncate(Exp memory exp) pure internal returns (uint) {
        // Note: We are not using careful math here as we're performing a division that cannot fail
        return exp.mantissa / expScale;
    }

    /**
     * @dev Multiply an Exp by a scalar, then truncate to return an unsigned integer.
     */
    function mul_ScalarTruncate(Exp memory a, uint scalar) pure internal returns (uint) {
        return truncate(mul_(a, scalar));
    }

    /**
     * @dev Multiply an Exp by a scalar, truncate, then add an to an unsigned integer, returning an unsigned integer.
     */
    function mul_ScalarTruncateAddUInt(Exp memory a, uint scalar, uint addend) pure internal returns (uint) {
        return truncate(mul_(a, scalar)) + addend;
    }

    /**
     * @dev Checks if first Exp is less than second Exp.
     */
    function lessThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
        return left.mantissa < right.mantissa;
    }

    /**
     * @dev Checks if left Exp <= right Exp.
     */
    function lessThanOrEqualExp(Exp memory left, Exp memory right) pure internal returns (bool) {
        return left.mantissa <= right.mantissa;
    }

    /**
     * @dev Checks if left Exp > right Exp.
     */
    function greaterThanExp(Exp memory left, Exp memory right) pure internal returns (bool) {
        return left.mantissa > right.mantissa;
    }

    /**
     * @dev returns true if Exp is exactly zero
     */
    function isZeroExp(Exp memory value) pure internal returns (bool) {
        return value.mantissa == 0;
    }

    function safe224(uint n) pure internal returns (uint224) {
        require(n <= type(uint224).max, "safe224 overflow");
        return uint224(n);
    }

    function safe32(uint n) pure internal returns (uint32) {
        require(n <= type(uint32).max, "safe32 overflow");
        return uint32(n);
    }

    function add_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
        return Exp({mantissa: a.mantissa + b.mantissa});
    }

    function add_(Double memory a, Double memory b) pure internal returns (Double memory) {
        return Double({mantissa: a.mantissa + b.mantissa});
    }

    function add_(uint a, uint b, string memory errorMessage) pure internal returns (uint c) {
        unchecked {
            require((c = a + b ) >= a, errorMessage);
        }
    }

    function sub_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
        return Exp({mantissa: a.mantissa - b.mantissa});
    }

    function sub_(Double memory a, Double memory b) pure internal returns (Double memory) {
        return Double({mantissa: a.mantissa - b.mantissa});
    }

    function sub_(uint a, uint b, string memory errorMessage) pure internal returns (uint c) {
        unchecked {
            require((c = a - b) <= a, errorMessage);
        }
    }

    function mul_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
        return Exp({mantissa: (a.mantissa * b.mantissa) / expScale});
    }

    function mul_(Exp memory a, uint b) pure internal returns (Exp memory) {
        return Exp({mantissa: a.mantissa * b});
    }

    function mul_(uint a, Exp memory b) pure internal returns (uint) {
        return (a * b.mantissa) / expScale;
    }

    function mul_(Double memory a, Double memory b) pure internal returns (Double memory) {
        return Double({mantissa: (a.mantissa * b.mantissa) / doubleScale});
    }

    function mul_(Double memory a, uint b) pure internal returns (Double memory) {
        return Double({mantissa: a.mantissa * b});
    }

    function mul_(uint a, Double memory b) pure internal returns (uint) {
        return (a * b.mantissa) / doubleScale;
    }

    function mul_(uint a, uint b, string memory errorMessage) pure internal returns (uint c) {
        unchecked {
            require(a == 0 || (c = a * b) / a == b, errorMessage);
        }
    }

    function div_(Exp memory a, Exp memory b) pure internal returns (Exp memory) {
        return Exp({mantissa: (a.mantissa * expScale) / b.mantissa});
    }

    function div_(Exp memory a, uint b) pure internal returns (Exp memory) {
        return Exp({mantissa: a.mantissa / b});
    }

    function div_(uint a, Exp memory b) pure internal returns (uint) {
        return (a * expScale) / b.mantissa;
    }

    function div_(Double memory a, Double memory b) pure internal returns (Double memory) {
        return Double({mantissa: (a.mantissa * doubleScale) / b.mantissa});
    }

    function div_(Double memory a, uint b) pure internal returns (Double memory) {
        return Double({mantissa: a.mantissa / b});
    }

    function div_(uint a, Double memory b) pure internal returns (uint) {
        return (a * doubleScale) / b.mantissa;
    }

    function div_(uint a, uint b, string memory errorMessage) pure internal returns (uint) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    function fraction(uint a, uint b) pure internal returns (Double memory) {
        return Double({mantissa: (a * doubleScale) / b});
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "./OTokenStorage.sol";

import "../../interfaces/IComptroller.sol";
import "../../libraries/ErrorReporter.sol";
import "../../libraries/Exponential.sol";
import "../interfaces/IEIP20.sol";
import "../../interest-rate-models/interfaces/IInterestRateModel.sol";
import "../../vote-escrow/interfaces/IBoostManager.sol";

/**
 * @title 0VIX's OToken Contract
 * @notice Abstract base for OTokens
 * @author 0VIX
 */
abstract contract OToken is OTokenStorage, Exponential, TokenErrorReporter {
    /**
     * @notice Initialize the money market
     * @param comptroller_ The address of the Comptroller
     * @param interestRateModel_ The address of the interest rate model
     * @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
     * @param name_ EIP-20 name of this token
     * @param symbol_ EIP-20 symbol of this token
     * @param decimals_ EIP-20 decimal precision of this token
     */
    function initialize(
        IComptroller comptroller_,
        IInterestRateModel interestRateModel_,
        uint256 initialExchangeRateMantissa_,
        string memory name_,
        string memory symbol_,
        uint8 decimals_
    ) internal {
        require(msg.sender == admin, "only admin may initialize");
        require(
            accrualBlockTimestamp == 0 && borrowIndex == 0,
            "already initialized"
        );

        // Set initial exchange rate
        initialExchangeRateMantissa = initialExchangeRateMantissa_;
        require(
            initialExchangeRateMantissa > 0,
            "init exchange rate must be > 0"
        );

        // Set the comptroller
        require(
            _setComptroller(comptroller_) == uint256(Error.NO_ERROR),
            "set comptroller failed"
        );

        // Initialize block timestamp and borrow index (block timestamp mocks depend on comptroller being set)
        accrualBlockTimestamp = getBlockTimestamp();
        borrowIndex = mantissaOne;

        // Set the interest rate model (depends on block timestamp / borrow index)
        require(
            _setInterestRateModelFresh(interestRateModel_) ==
                uint256(Error.NO_ERROR),
            "set interest rate model failed"
        );

        name = name_;
        symbol = symbol_;
        decimals = decimals_;

        // The counter starts true to prevent changing it from zero to non-zero (i.e. smaller cost/refund)
        _notEntered = true;
    }

    function _updateBoostSupplyBalances(
        address user,
        uint256 oldBalance,
        uint256 newBalance
    ) internal {
        address boostManager = comptroller.getBoostManager();
        if (
            boostManager != address(0) &&
            IBoostManager(boostManager).isAuthorized(address(this))
        ) {
            IBoostManager(boostManager).updateBoostSupplyBalances(
                address(this),
                user,
                oldBalance,
                newBalance
            );
        }
    }

    function _updateBoostBorrowBalances(
        address user,
        uint256 oldBalance,
        uint256 newBalance
    ) internal {
        address boostManager = comptroller.getBoostManager();
        if (
            boostManager != address(0) &&
            IBoostManager(boostManager).isAuthorized(address(this))
        ) {
            IBoostManager(boostManager).updateBoostBorrowBalances(
                address(this),
                user,
                oldBalance,
                newBalance
            );
        }
    }

    /**
     * @notice Transfer `tokens` tokens from `src` to `dst` by `spender`
     * @dev Called by both `transfer` and `transferFrom` internally
     * @param spender The address of the account performing the transfer
     * @param src The address of the source account
     * @param dst The address of the destination account
     * @param tokens The number of tokens to transfer
     * @return Whether or not the transfer succeeded
     */
    function transferTokens(
        address spender,
        address src,
        address dst,
        uint256 tokens
    ) internal returns (uint256) {
        /* Fail if transfer not allowed */
        uint256 allowed = comptroller.transferAllowed(
            address(this),
            src,
            dst,
            tokens
        );
        require(allowed == 0, "ERC20: transfer not allowed");

        /* Do not allow self-transfers */
        require(src != dst, "ERC20: self-transfer not allowed");

        /* Get the allowance, infinite for the account owner */
        uint256 startingAllowance = 0;
        if (spender == src) {
            startingAllowance = type(uint256).max;
        } else {
            startingAllowance = transferAllowances[src][spender];
        }

        /* Do the calculations, checking for {under,over}flow */
        MathError mathErr;
        uint256 allowanceNew;
        uint256 srcTokensNew;
        uint256 dstTokensNew;

        (mathErr, allowanceNew) = subUInt(startingAllowance, tokens);
        require(
            mathErr == MathError.NO_ERROR,
            "ERC20: decreased allowance below zero"
        );

        (mathErr, srcTokensNew) = subUInt(accountTokens[src], tokens);
        require(
            mathErr == MathError.NO_ERROR,
            "ERC20: transfer amount exceeds balance"
        );

        (mathErr, dstTokensNew) = addUInt(accountTokens[dst], tokens);
        require(
            mathErr == MathError.NO_ERROR,
            "ERC20: maximum destination balance reached"
        );

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        _updateBoostSupplyBalances(src, accountTokens[src], srcTokensNew);
        _updateBoostSupplyBalances(dst, accountTokens[dst], dstTokensNew);

        accountTokens[src] = srcTokensNew;
        accountTokens[dst] = dstTokensNew;

        /* Eat some of the allowance (if necessary) */
        if (startingAllowance != type(uint256).max) {
            transferAllowances[src][spender] = allowanceNew;
        }

        /* We emit a Transfer event */
        emit Transfer(src, dst, tokens);

        // unused function
        // comptroller.transferVerify(address(this), src, dst, tokens);

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Transfer `amount` tokens from `msg.sender` to `dst`
     * @param dst The address of the destination account
     * @param amount The number of tokens to transfer
     * @return Whether or not the transfer succeeded
     */
    function transfer(address dst, uint256 amount)
        external
        override
        nonReentrant
        returns (bool)
    {
        return
            transferTokens(msg.sender, msg.sender, dst, amount) ==
            uint256(Error.NO_ERROR);
    }

    /**
     * @notice Transfer `amount` tokens from `src` to `dst`
     * @param src The address of the source account
     * @param dst The address of the destination account
     * @param amount The number of tokens to transfer
     * @return Whether or not the transfer succeeded
     */
    function transferFrom(
        address src,
        address dst,
        uint256 amount
    ) external override nonReentrant returns (bool) {
        return
            transferTokens(msg.sender, src, dst, amount) ==
            uint256(Error.NO_ERROR);
    }

    /**
     * @notice Approve `spender` to transfer up to `amount` from `src`
     * @dev This will overwrite the approval amount for `spender`
     *  and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
     * @param spender The address of the account which may transfer tokens
     * @param amount The number of tokens that are approved (-1 means infinite)
     * @return Whether or not the approval succeeded
     */
    function approve(address spender, uint256 amount)
        external
        override
        returns (bool)
    {
        address src = msg.sender;
        transferAllowances[src][spender] = amount;
        emit Approval(src, spender, amount);
        return true;
    }

    /**
     * @notice Get the current allowance from `owner` for `spender`
     * @param owner The address of the account which owns the tokens to be spent
     * @param spender The address of the account which may transfer tokens
     * @return The number of tokens allowed to be spent (-1 means infinite)
     */
    function allowance(address owner, address spender)
        external
        view
        override
        returns (uint256)
    {
        return transferAllowances[owner][spender];
    }

    /**
     * @notice Get the token balance of the `owner`
     * @param owner The address of the account to query
     * @return The number of tokens owned by `owner`
     */
    function balanceOf(address owner) external view override returns (uint256) {
        return accountTokens[owner];
    }

    /**
     * @notice Get the underlying balance of the `owner`
     * @dev This also accrues interest in a transaction
     * @param owner The address of the account to query
     * @return The amount of underlying owned by `owner`
     */
    function balanceOfUnderlying(address owner)
        external
        override
        returns (uint256)
    {
        Exp memory exchangeRate = Exp({mantissa: exchangeRateCurrent()});
        (MathError mErr, uint256 balance) = mulScalarTruncate(
            exchangeRate,
            accountTokens[owner]
        );
        require(mErr == MathError.NO_ERROR, "balance could not be calculated");
        return balance;
    }

    /**
     * @notice Get a snapshot of the account's balances, and the cached exchange rate
     * @dev This is used by comptroller to more efficiently perform liquidity checks.
     * @param account Address of the account to snapshot
     * @return (possible error, token balance, borrow balance, exchange rate mantissa)
     */
    function getAccountSnapshot(address account)
        external
        view
        override
        returns (
            uint256,
            uint256,
            uint256,
            uint256
        )
    {
        uint256 oTokenBalance = accountTokens[account];
        uint256 borrowBalance;
        uint256 exchangeRateMantissa;

        MathError mErr;

        (mErr, borrowBalance) = borrowBalanceStoredInternal(account);
        if (mErr != MathError.NO_ERROR) {
            return (uint256(Error.MATH_ERROR), 0, 0, 0);
        }

        (mErr, exchangeRateMantissa) = exchangeRateStoredInternal();
        if (mErr != MathError.NO_ERROR) {
            return (uint256(Error.MATH_ERROR), 0, 0, 0);
        }

        return (
            uint256(Error.NO_ERROR),
            oTokenBalance,
            borrowBalance,
            exchangeRateMantissa
        );
    }

    /**
     * @dev Function to simply retrieve block timestamp
     *  This exists mainly for inheriting test contracts to stub this result.
     */
    function getBlockTimestamp() internal view virtual returns (uint256) {
        return block.timestamp;
    }

    /**
     * @notice Returns the current per-timestamp borrow interest rate for this oToken
     * @return The borrow interest rate per timestmp, scaled by 1e18
     */
    function borrowRatePerTimestamp() external view override returns (uint256) {
        return
            interestRateModel.getBorrowRate(
                getCashPrior(),
                totalBorrows,
                totalReserves
            );
    }

    /**
     * @notice Returns the current per-timestamp supply interest rate for this oToken
     * @return The supply interest rate per timestmp, scaled by 1e18
     */
    function supplyRatePerTimestamp() external view override returns (uint256) {
        return
            interestRateModel.getSupplyRate(
                getCashPrior(),
                totalBorrows,
                totalReserves,
                reserveFactorMantissa
            );
    }

    /**
     * @notice Returns the current total borrows plus accrued interest
     * @return The total borrows with interest
     */
    function totalBorrowsCurrent()
        external
        override
        nonReentrant
        returns (uint256)
    {
        require(
            accrueInterest() == uint256(Error.NO_ERROR),
            "accrue interest failed"
        );
        return totalBorrows;
    }

    /**
     * @notice Accrue interest to updated borrowIndex and then calculate account's borrow balance using the updated borrowIndex
     * @param account The address whose balance should be calculated after updating borrowIndex
     * @return The calculated balance
     */
    function borrowBalanceCurrent(address account)
        external
        override
        nonReentrant
        returns (uint256)
    {
        require(
            accrueInterest() == uint256(Error.NO_ERROR),
            "accrue interest failed"
        );
        return borrowBalanceStored(account);
    }

    /**
     * @notice Return the borrow balance of account based on stored data
     * @param account The address whose balance should be calculated
     * @return The calculated balance
     */
    function borrowBalanceStored(address account)
        public
        view
        override
        returns (uint256)
    {
        (MathError err, uint256 result) = borrowBalanceStoredInternal(account);
        require(err == MathError.NO_ERROR, "borrowBalanceStored failed");
        return result;
    }

    /**
     * @notice Return the borrow balance of account based on stored data
     * @param account The address whose balance should be calculated
     * @return (error code, the calculated balance or 0 if error code is non-zero)
     */
    function borrowBalanceStoredInternal(address account)
        internal
        view
        returns (MathError, uint256)
    {
        /* Note: we do not assert that the market is up to date */
        MathError mathErr;
        uint256 principalTimesIndex;
        uint256 result;

        /* Get borrowBalance and borrowIndex */
        BorrowSnapshot storage borrowSnapshot = accountBorrows[account];

        /* If borrowBalance = 0 then borrowIndex is likely also 0.
         * Rather than failing the calculation with a division by 0, we immediately return 0 in this case.
         */
        if (borrowSnapshot.principal == 0) {
            return (MathError.NO_ERROR, 0);
        }

        /* Calculate new borrow balance using the interest index:
         *  recentBorrowBalance = borrower.borrowBalance * market.borrowIndex / borrower.borrowIndex
         */
        (mathErr, principalTimesIndex) = mulUInt(
            borrowSnapshot.principal,
            borrowIndex
        );
        if (mathErr != MathError.NO_ERROR) {
            return (mathErr, 0);
        }

        (mathErr, result) = divUInt(
            principalTimesIndex,
            borrowSnapshot.interestIndex
        );
        if (mathErr != MathError.NO_ERROR) {
            return (mathErr, 0);
        }

        return (MathError.NO_ERROR, result);
    }

    /**
     * @notice Accrue interest then return the up-to-date exchange rate
     * @return Calculated exchange rate scaled by 1e18
     */
    function exchangeRateCurrent()
        public
        override
        nonReentrant
        returns (uint256)
    {
        require(
            accrueInterest() == uint256(Error.NO_ERROR),
            "accrue interest failed"
        );
        return exchangeRateStored();
    }

    /**
     * @notice Calculates the exchange rate from the underlying to the OToken
     * @dev This function does not accrue interest before calculating the exchange rate
     * @return Calculated exchange rate scaled by 1e18
     */
    function exchangeRateStored() public view override returns (uint256) {
        (MathError err, uint256 result) = exchangeRateStoredInternal();
        require(err == MathError.NO_ERROR, "exchangeRateStored failed");
        return result;
    }

    /**
     * @notice Calculates the exchange rate from the underlying to the OToken
     * @dev This function does not accrue interest before calculating the exchange rate
     * @return (error code, calculated exchange rate scaled by 1e18)
     */
    function exchangeRateStoredInternal()
        internal
        view
        virtual
        returns (MathError, uint256)
    {
        uint256 _totalSupply = totalSupply;
        if (_totalSupply == 0) {
            /*
             * If there are no tokens minted:
             *  exchangeRate = initialExchangeRate
             */
            return (MathError.NO_ERROR, initialExchangeRateMantissa);
        } else {
            /*
             * Otherwise:
             *  exchangeRate = (totalCash + totalBorrows - totalReserves) / totalSupply
             */
            uint256 totalCash = getCashPrior();
            uint256 cashPlusBorrowsMinusReserves;
            Exp memory exchangeRate;
            MathError mathErr;

            (mathErr, cashPlusBorrowsMinusReserves) = addThenSubUInt(
                totalCash,
                totalBorrows,
                totalReserves
            );
            if (mathErr != MathError.NO_ERROR) {
                return (mathErr, 0);
            }

            (mathErr, exchangeRate) = getExp(
                cashPlusBorrowsMinusReserves,
                _totalSupply
            );
            if (mathErr != MathError.NO_ERROR) {
                return (mathErr, 0);
            }

            return (MathError.NO_ERROR, exchangeRate.mantissa);
        }
    }

    /**
     * @notice Get cash balance of this oToken in the underlying asset
     * @return The quantity of underlying asset owned by this contract
     */
    function getCash() external view override returns (uint256) {
        return getCashPrior();
    }

    /**
     * @notice Applies accrued interest to total borrows and reserves
     * @dev This calculates interest accrued from the last checkpointed block
     *   up to the current block and writes new checkpoint to storage.
     */
    function accrueInterest() public override returns (uint256) {
        /* Remember the initial block timestamp */
        uint256 currentBlockTimestamp = getBlockTimestamp();
        uint256 accrualBlockTimestampPrior = accrualBlockTimestamp;

        /* Short-circuit accumulating 0 interest */
        if (accrualBlockTimestampPrior == currentBlockTimestamp) {
            return uint256(Error.NO_ERROR);
        }

        /* Read the previous values out of storage */
        uint256 cashPrior = getCashPrior();
        uint256 borrowsPrior = totalBorrows;
        uint256 reservesPrior = totalReserves;
        uint256 borrowIndexPrior = borrowIndex;

        /* Calculate the current borrow interest rate */
        uint256 borrowRateMantissa = interestRateModel.getBorrowRate(
            cashPrior,
            borrowsPrior,
            reservesPrior
        );
        require(
            borrowRateMantissa <= borrowRateMaxMantissa,
            "borrow rate is absurdly high"
        );

        /* Calculate the number of blocks elapsed since the last accrual */
        (MathError mathErr, uint256 blockDelta) = subUInt(
            currentBlockTimestamp,
            accrualBlockTimestampPrior
        );
        require(
            mathErr == MathError.NO_ERROR,
            "could not calculate block delta"
        );

        /*
         * Calculate the interest accumulated into borrows and reserves and the new index:
         *  simpleInterestFactor = borrowRate * blockDelta
         *  interestAccumulated = simpleInterestFactor * totalBorrows
         *  totalBorrowsNew = interestAccumulated + totalBorrows
         *  totalReservesNew = interestAccumulated * reserveFactor + totalReserves
         *  borrowIndexNew = simpleInterestFactor * borrowIndex + borrowIndex
         */

        Exp memory simpleInterestFactor;
        uint256 interestAccumulated;
        uint256 totalBorrowsNew;
        uint256 totalReservesNew;
        uint256 borrowIndexNew;

        (mathErr, simpleInterestFactor) = mulScalar(
            Exp({mantissa: borrowRateMantissa}),
            blockDelta
        );
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .ACCRUE_INTEREST_SIMPLE_INTEREST_FACTOR_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        (mathErr, interestAccumulated) = mulScalarTruncate(
            simpleInterestFactor,
            borrowsPrior
        );
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .ACCRUE_INTEREST_ACCUMULATED_INTEREST_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        (mathErr, totalBorrowsNew) = addUInt(interestAccumulated, borrowsPrior);
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .ACCRUE_INTEREST_NEW_TOTAL_BORROWS_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        (mathErr, totalReservesNew) = mulScalarTruncateAddUInt(
            Exp({mantissa: reserveFactorMantissa}),
            interestAccumulated,
            reservesPrior
        );
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .ACCRUE_INTEREST_NEW_TOTAL_RESERVES_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        (mathErr, borrowIndexNew) = mulScalarTruncateAddUInt(
            simpleInterestFactor,
            borrowIndexPrior,
            borrowIndexPrior
        );
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .ACCRUE_INTEREST_NEW_BORROW_INDEX_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /* We write the previously calculated values into storage */
        accrualBlockTimestamp = currentBlockTimestamp;
        borrowIndex = borrowIndexNew;
        totalBorrows = totalBorrowsNew;
        totalReserves = totalReservesNew;

        /* We emit an AccrueInterest event */
        emit AccrueInterest(
            cashPrior,
            interestAccumulated,
            borrowIndexNew,
            totalBorrowsNew
        );

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Sender supplies assets into the market and receives oTokens in exchange
     * @dev Accrues interest whether or not the operation succeeds, unless reverted
     * @param mintAmount The amount of the underlying asset to supply
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
     */
    function mintInternal(uint256 mintAmount)
        internal
        nonReentrant
        returns (uint256, uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
            return (
                fail(Error(error), FailureInfo.MINT_ACCRUE_INTEREST_FAILED),
                0
            );
        }
        // mintFresh emits the actual Mint event if successful and logs on errors, so we don't need to
        return mintFresh(msg.sender, mintAmount);
    }

    struct MintLocalVars {
        Error err;
        MathError mathErr;
    }

    /**
     * @notice User supplies assets into the market and receives oTokens in exchange
     * @dev Assumes interest has already been accrued up to the current block
     * @param minter The address of the account which is supplying the assets
     * @param mintAmount The amount of the underlying asset to supply
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual mint amount.
     */
    function mintFresh(address minter, uint256 mintAmount)
        internal
        returns (uint256, uint256)
    {
        /* Fail if mint not allowed */
        {
            uint256 allowed = comptroller.mintAllowed(
                address(this),
                minter,
                mintAmount
            );
            if (allowed != 0) {
                return (
                    failOpaque(
                        Error.COMPTROLLER_REJECTION,
                        FailureInfo.MINT_COMPTROLLER_REJECTION,
                        allowed
                    ),
                    0
                );
            }
        }

        /* Verify market's block timestamp equals current block timestamp */
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return (
                fail(Error.MARKET_NOT_FRESH, FailureInfo.MINT_FRESHNESS_CHECK),
                0
            );
        }

        MintLocalVars memory vars;
        uint256 exchangeRateMantissa;
        (vars.mathErr, exchangeRateMantissa) = exchangeRateStoredInternal();
        if (vars.mathErr != MathError.NO_ERROR) {
            return (
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.MINT_EXCHANGE_RATE_READ_FAILED,
                    uint256(vars.mathErr)
                ),
                0
            );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /*
         *  We call `doTransferIn` for the minter and the mintAmount.
         *  Note: The oToken must handle variations between ERC-20 and NATIVE underlying.
         *  `doTransferIn` reverts if anything goes wrong, since we can't be sure if
         *  side-effects occurred. The function returns the amount actually transferred,
         *  in case of a fee. On success, the oToken holds an additional `actualMintAmount`
         *  of cash.
         */
        uint256 actualMintAmount = doTransferIn(minter, mintAmount);

        /*
         * We get the current exchange rate and calculate the number of oTokens to be minted:
         *  mintTokens = actualMintAmount / exchangeRate
         */

        uint256 mintTokens;
        (vars.mathErr, mintTokens) = divScalarByExpTruncate(
            actualMintAmount,
            Exp({mantissa: exchangeRateMantissa})
        );
        require(
            vars.mathErr == MathError.NO_ERROR,
            "MINT_EXCHANGE_CALCULATION_FAILED"
        );

        /*
         * We calculate the new total supply of oTokens and minter token balance, checking for overflow:
         *  totalSupplyNew = totalSupply + mintTokens
         *  accountTokensNew = accountTokens[minter] + mintTokens
         */
        uint256 totalSupplyNew;
        (vars.mathErr, totalSupplyNew) = addUInt(totalSupply, mintTokens);
        require(
            vars.mathErr == MathError.NO_ERROR,
            "MINT_NEW_TOTAL_SUPPLY_FAILED"
        );

        uint256 accountTokensNew;
        (vars.mathErr, accountTokensNew) = addUInt(
            accountTokens[minter],
            mintTokens
        );
        require(
            vars.mathErr == MathError.NO_ERROR,
            "MINT_NEW_ACCOUNT_BALANCE_FAILED"
        );

        _updateBoostSupplyBalances(
            minter,
            accountTokens[minter],
            accountTokensNew
        );

        /* We write previously calculated values into storage */
        totalSupply = totalSupplyNew;
        accountTokens[minter] = accountTokensNew;

        /* We emit a Mint event, and a Transfer event */
        emit Mint(minter, actualMintAmount, mintTokens);
        emit Transfer(address(0), minter, mintTokens);

        /* We call the defense hook */
        // unused function
        // comptroller.mintVerify(address(this), minter, vars.actualMintAmount, vars.mintTokens);

        return (uint256(Error.NO_ERROR), actualMintAmount);
    }

    /**
     * @notice Sender redeems oTokens in exchange for the underlying asset
     * @dev Accrues interest whether or not the operation succeeds, unless reverted
     * @param redeemTokens The number of oTokens to redeem into underlying
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function redeemInternal(uint256 redeemTokens)
        internal
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
            return
                fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
        }
        // redeemFresh emits redeem-specific logs on errors, so we don't need to
        return redeemFresh(payable(msg.sender), redeemTokens, 0);
    }

    /**
     * @notice Sender redeems oTokens in exchange for a specified amount of underlying asset
     * @dev Accrues interest whether or not the operation succeeds, unless reverted
     * @param redeemAmount The amount of underlying to receive from redeeming oTokens
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function redeemUnderlyingInternal(uint256 redeemAmount)
        internal
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted redeem failed
            return
                fail(Error(error), FailureInfo.REDEEM_ACCRUE_INTEREST_FAILED);
        }
        // redeemFresh emits redeem-specific logs on errors, so we don't need to
        return redeemFresh(payable(msg.sender), 0, redeemAmount);
    }

    struct RedeemLocalVars {
        Error err;
        MathError mathErr;
        uint256 exchangeRateMantissa;
        uint256 redeemTokens;
        uint256 redeemAmount;
        uint256 totalSupplyNew;
        uint256 accountTokensNew;
    }

    /**
     * @notice User redeems oTokens in exchange for the underlying asset
     * @dev Assumes interest has already been accrued up to the current block
     * @param redeemer The address of the account which is redeeming the tokens
     * @param redeemTokensIn The number of oTokens to redeem into underlying (only one of redeemTokensIn or redeemAmountIn may be non-zero)
     * @param redeemAmountIn The number of underlying tokens to receive from redeeming oTokens (only one of redeemTokensIn or redeemAmountIn may be non-zero)
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function redeemFresh(
        address payable redeemer,
        uint256 redeemTokensIn,
        uint256 redeemAmountIn
    ) internal returns (uint256) {
        require(
            redeemTokensIn == 0 || redeemAmountIn == 0,
            "tokensIn or amountIn must be 0"
        );

        RedeemLocalVars memory vars;

        /* exchangeRate = invoke Exchange Rate Stored() */
        (
            vars.mathErr,
            vars.exchangeRateMantissa
        ) = exchangeRateStoredInternal();
        if (vars.mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.REDEEM_EXCHANGE_RATE_READ_FAILED,
                    uint256(vars.mathErr)
                );
        }

        /* If redeemTokensIn > 0: */
        if (redeemTokensIn > 0) {
            /*
             * We calculate the exchange rate and the amount of underlying to be redeemed:
             *  redeemTokens = redeemTokensIn
             *  redeemAmount = redeemTokensIn x exchangeRateCurrent
             */
            if (redeemTokensIn >= accountTokens[redeemer]) {
                vars.redeemTokens = accountTokens[redeemer];
            } else {
                vars.redeemTokens = redeemTokensIn;
            }

            (vars.mathErr, vars.redeemAmount) = mulScalarTruncate(
                Exp({mantissa: vars.exchangeRateMantissa}),
                vars.redeemTokens
            );
            if (vars.mathErr != MathError.NO_ERROR) {
                return
                    failOpaque(
                        Error.MATH_ERROR,
                        FailureInfo.REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
                        uint256(vars.mathErr)
                    );
            }
        } else {
            /*
             * We get the current exchange rate and calculate the amount to be redeemed:
             *  redeemTokens = redeemAmountIn / exchangeRate
             *  redeemAmount = redeemAmountIn
             */
            if (redeemAmountIn == type(uint256).max) {
                vars.redeemTokens = accountTokens[redeemer];

                (vars.mathErr, vars.redeemAmount) = mulScalarTruncate(
                    Exp({mantissa: vars.exchangeRateMantissa}),
                    vars.redeemTokens
                );
                if (vars.mathErr != MathError.NO_ERROR) {
                    return
                        failOpaque(
                            Error.MATH_ERROR,
                            FailureInfo
                                .REDEEM_EXCHANGE_TOKENS_CALCULATION_FAILED,
                            uint256(vars.mathErr)
                        );
                }
            } else {
                vars.redeemAmount = redeemAmountIn;

                (vars.mathErr, vars.redeemTokens) = divScalarByExpTruncate(
                    redeemAmountIn,
                    Exp({mantissa: vars.exchangeRateMantissa})
                );
                if (vars.mathErr != MathError.NO_ERROR) {
                    return
                        failOpaque(
                            Error.MATH_ERROR,
                            FailureInfo
                                .REDEEM_EXCHANGE_AMOUNT_CALCULATION_FAILED,
                            uint256(vars.mathErr)
                        );
                }
            }
        }

        /* Fail if redeem not allowed */
        uint256 allowed = comptroller.redeemAllowed(
            address(this),
            redeemer,
            vars.redeemTokens
        );
        if (allowed != 0) {
            return
                failOpaque(
                    Error.COMPTROLLER_REJECTION,
                    FailureInfo.REDEEM_COMPTROLLER_REJECTION,
                    allowed
                );
        }

        /* Verify market's block timestamp equals current block timestamp */
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.REDEEM_FRESHNESS_CHECK
                );
        }

        /*
         * We calculate the new total supply and redeemer balance, checking for underflow:
         *  totalSupplyNew = totalSupply - redeemTokens
         *  accountTokensNew = accountTokens[redeemer] - redeemTokens
         */
        (vars.mathErr, vars.totalSupplyNew) = subUInt(
            totalSupply,
            vars.redeemTokens
        );
        if (vars.mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.REDEEM_NEW_TOTAL_SUPPLY_CALCULATION_FAILED,
                    uint256(vars.mathErr)
                );
        }
        if (vars.redeemTokens > accountTokens[redeemer])
            vars.redeemTokens = accountTokens[redeemer];
        (vars.mathErr, vars.accountTokensNew) = subUInt(
            accountTokens[redeemer],
            vars.redeemTokens
        );
        if (vars.mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.REDEEM_NEW_ACCOUNT_BALANCE_CALCULATION_FAILED,
                    uint256(vars.mathErr)
                );
        }

        /* Fail gracefully if protocol has insufficient cash */
        if (getCashPrior() < vars.redeemAmount) {
            return
                fail(
                    Error.TOKEN_INSUFFICIENT_CASH,
                    FailureInfo.REDEEM_TRANSFER_OUT_NOT_POSSIBLE
                );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        _updateBoostSupplyBalances(
            redeemer,
            accountTokens[redeemer],
            vars.accountTokensNew
        );
        /* We write previously calculated values into storage */
        totalSupply = vars.totalSupplyNew;
        accountTokens[redeemer] = vars.accountTokensNew;

        /* We emit a Transfer event, and a Redeem event */
        emit Transfer(redeemer, address(this), vars.redeemTokens);
        emit Redeem(redeemer, vars.redeemAmount, vars.redeemTokens);

        /* We call the defense hook */
        comptroller.redeemVerify(
            address(this),
            redeemer,
            vars.redeemAmount,
            vars.redeemTokens
        );

        /*
         * We invoke doTransferOut for the redeemer and the redeemAmount.
         *  Note: The oToken must handle variations between ERC-20 and NATIVE underlying.
         *  On success, the oToken has redeemAmount less of cash.
         *  doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
         */
        doTransferOut(redeemer, vars.redeemAmount);

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Sender borrows assets from the protocol to their own address
     * @param borrowAmount The amount of the underlying asset to borrow
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function borrowInternal(uint256 borrowAmount)
        internal
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
            return
                fail(Error(error), FailureInfo.BORROW_ACCRUE_INTEREST_FAILED);
        }
        // borrowFresh emits borrow-specific logs on errors, so we don't need to
        return borrowFresh(payable(msg.sender), borrowAmount);
    }

    /**
     * @notice Users borrow assets from the protocol to their own address
     * @param borrowAmount The amount of the underlying asset to borrow
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function borrowFresh(address payable borrower, uint256 borrowAmount)
        internal
        returns (uint256)
    {
        /* Fail if borrow not allowed */
        {
            uint256 allowed = comptroller.borrowAllowed(
                address(this),
                borrower,
                borrowAmount
            );
            if (allowed != 0) {
                return
                    failOpaque(
                        Error.COMPTROLLER_REJECTION,
                        FailureInfo.BORROW_COMPTROLLER_REJECTION,
                        allowed
                    );
            }
        }

        /* Verify market's block timestamp equals current block timestamp */
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.BORROW_FRESHNESS_CHECK
                );
        }

        /* Fail gracefully if protocol has insufficient underlying cash */
        if (getCashPrior() < borrowAmount) {
            return
                fail(
                    Error.TOKEN_INSUFFICIENT_CASH,
                    FailureInfo.BORROW_CASH_NOT_AVAILABLE
                );
        }

        MathError mathErr;

        /*
         * We calculate the new borrower and total borrow balances, failing on overflow:
         *  accountBorrowsNew = accountBorrows + borrowAmount
         *  totalBorrowsNew = totalBorrows + borrowAmount
         */
        uint256 _accountBorrows;
        (mathErr, _accountBorrows) = borrowBalanceStoredInternal(borrower);
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }
        uint256 oldBorrowedBalance = _accountBorrows;

        uint256 accountBorrowsNew;
        (mathErr, accountBorrowsNew) = addUInt(_accountBorrows, borrowAmount);
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .BORROW_NEW_ACCOUNT_BORROW_BALANCE_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        uint256 totalBorrowsNew;
        (mathErr, totalBorrowsNew) = addUInt(totalBorrows, borrowAmount);
        if (mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.BORROW_NEW_TOTAL_BALANCE_CALCULATION_FAILED,
                    uint256(mathErr)
                );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /* We write the previously calculated values into storage */
        accountBorrows[borrower].principal = accountBorrowsNew;
        accountBorrows[borrower].interestIndex = borrowIndex;
        totalBorrows = totalBorrowsNew;

        /* We emit a Borrow event */
        emit Borrow(borrower, borrowAmount, accountBorrowsNew, totalBorrowsNew);

        _updateBoostBorrowBalances(
            borrower,
            oldBorrowedBalance,
            accountBorrowsNew
        );

        /* We call the defense hook */
        // unused function
        // comptroller.borrowVerify(address(this), borrower, borrowAmount);

        /*
         * We invoke doTransferOut for the borrower and the borrowAmount.
         *  Note: The oToken must handle variations between ERC-20 and NATIVE underlying.
         *  On success, the oToken borrowAmount less of cash.
         *  doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
         */
        doTransferOut(borrower, borrowAmount);

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Sender repays their own borrow
     * @param repayAmount The amount to repay
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
     */
    function repayBorrowInternal(uint256 repayAmount)
        internal
        nonReentrant
        returns (uint256, uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
            return (
                fail(
                    Error(error),
                    FailureInfo.REPAY_BORROW_ACCRUE_INTEREST_FAILED
                ),
                0
            );
        }
        // repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
        return repayBorrowFresh(msg.sender, msg.sender, repayAmount);
    }

    /**
     * @notice Sender repays a borrow belonging to borrower
     * @param borrower the account with the debt being payed off
     * @param repayAmount The amount to repay
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
     */
    function repayBorrowBehalfInternal(address borrower, uint256 repayAmount)
        internal
        nonReentrant
        returns (uint256, uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted borrow failed
            return (
                fail(
                    Error(error),
                    FailureInfo.REPAY_BEHALF_ACCRUE_INTEREST_FAILED
                ),
                0
            );
        }
        // repayBorrowFresh emits repay-borrow-specific logs on errors, so we don't need to
        return repayBorrowFresh(msg.sender, borrower, repayAmount);
    }

    struct RepayBorrowLocalVars {
        Error err;
        MathError mathErr;
        uint256 repayAmount;
        uint256 borrowerIndex;
        uint256 accountBorrows;
        uint256 accountBorrowsNew;
        uint256 totalBorrowsNew;
        uint256 actualRepayAmount;
    }

    /**
     * @notice Borrows are repaid by another user (possibly the borrower).
     * @param payer the account paying off the borrow
     * @param borrower the account with the debt being payed off
     * @param repayAmount the amount of undelrying tokens being returned
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
     */
    function repayBorrowFresh(
        address payer,
        address borrower,
        uint256 repayAmount
    ) internal returns (uint256, uint256) {
        /* Fail if repayBorrow not allowed */
        uint256 allowed = comptroller.repayBorrowAllowed(
            address(this),
            payer,
            borrower,
            repayAmount
        );
        if (allowed != 0) {
            return (
                failOpaque(
                    Error.COMPTROLLER_REJECTION,
                    FailureInfo.REPAY_BORROW_COMPTROLLER_REJECTION,
                    allowed
                ),
                0
            );
        }

        /* Verify market's block timestamp equals current block timestamp */
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return (
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.REPAY_BORROW_FRESHNESS_CHECK
                ),
                0
            );
        }

        RepayBorrowLocalVars memory vars;
        uint256 oldBorrowedBalance = borrowBalanceStored(borrower);

        /* We remember the original borrowerIndex for verification purposes */
        vars.borrowerIndex = accountBorrows[borrower].interestIndex;

        /* We fetch the amount the borrower owes, with accumulated interest */
        (vars.mathErr, vars.accountBorrows) = borrowBalanceStoredInternal(
            borrower
        );
        if (vars.mathErr != MathError.NO_ERROR) {
            return (
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo
                        .REPAY_BORROW_ACCUMULATED_BALANCE_CALCULATION_FAILED,
                    uint256(vars.mathErr)
                ),
                0
            );
        }

        /* If repayAmount >= accountBorrows, repayAmount = accountBorrows */
        if (repayAmount >= vars.accountBorrows) {
            vars.repayAmount = vars.accountBorrows;
        } else {
            vars.repayAmount = repayAmount;
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /*
         * We call doTransferIn for the payer and the repayAmount
         *  Note: The oToken must handle variations between ERC-20 and NATIVE underlying.
         *  On success, the oToken holds an additional repayAmount of cash.
         *  doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
         *   it returns the amount actually transferred, in case of a fee.
         */
        vars.actualRepayAmount = doTransferIn(payer, vars.repayAmount);

        /*
         * We calculate the new borrower and total borrow balances, failing on underflow:
         *  accountBorrowsNew = accountBorrows - actualRepayAmount
         *  totalBorrowsNew = totalBorrows - actualRepayAmount
         */
        (vars.mathErr, vars.accountBorrowsNew) = subUInt(
            vars.accountBorrows,
            vars.actualRepayAmount
        );
        require(
            vars.mathErr == MathError.NO_ERROR,
            "REPAY_NEW_ACCOUNT_BALANCE_FAILED"
        );

        (vars.mathErr, vars.totalBorrowsNew) = subUInt(
            totalBorrows,
            vars.actualRepayAmount
        );
        require(
            vars.mathErr == MathError.NO_ERROR,
            "REPAY_NEW_TOTAL_BALANCE_FAILED"
        );

        /* We write the previously calculated values into storage */
        accountBorrows[borrower].principal = vars.accountBorrowsNew;
        accountBorrows[borrower].interestIndex = borrowIndex;
        totalBorrows = vars.totalBorrowsNew;

        /* We emit a RepayBorrow event */
        emit RepayBorrow(
            payer,
            borrower,
            vars.actualRepayAmount,
            vars.accountBorrowsNew,
            vars.totalBorrowsNew
        );
        _updateBoostBorrowBalances(
            borrower,
            oldBorrowedBalance,
            vars.accountBorrowsNew
        );

        /* We call the defense hook */
        // unused function
        // comptroller.repayBorrowVerify(address(this), payer, borrower, vars.actualRepayAmount, vars.borrowerIndex);

        return (uint256(Error.NO_ERROR), vars.actualRepayAmount);
    }

    /**
     * @notice The sender liquidates the borrowers collateral.
     *  The collateral seized is transferred to the liquidator.
     * @param borrower The borrower of this oToken to be liquidated
     * @param oTokenCollateral The market in which to seize collateral from the borrower
     * @param repayAmount The amount of the underlying borrowed asset to repay
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
     */
    function liquidateBorrowInternal(
        address borrower,
        uint256 repayAmount,
        IOToken oTokenCollateral
    ) internal nonReentrant returns (uint256, uint256) {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
            return (
                fail(
                    Error(error),
                    FailureInfo.LIQUIDATE_ACCRUE_BORROW_INTEREST_FAILED
                ),
                0
            );
        }

        error = oTokenCollateral.accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but we still want to log the fact that an attempted liquidation failed
            return (
                fail(
                    Error(error),
                    FailureInfo.LIQUIDATE_ACCRUE_COLLATERAL_INTEREST_FAILED
                ),
                0
            );
        }

        // liquidateBorrowFresh emits borrow-specific logs on errors, so we don't need to
        return
            liquidateBorrowFresh(
                msg.sender,
                borrower,
                repayAmount,
                oTokenCollateral
            );
    }

    /**
     * @notice The liquidator liquidates the borrowers collateral.
     *  The collateral seized is transferred to the liquidator.
     * @param borrower The borrower of this oToken to be liquidated
     * @param liquidator The address repaying the borrow and seizing collateral
     * @param oTokenCollateral The market in which to seize collateral from the borrower
     * @param repayAmount The amount of the underlying borrowed asset to repay
     * @return (uint, uint) An error code (0=success, otherwise a failure, see ErrorReporter.sol), and the actual repayment amount.
     */
    function liquidateBorrowFresh(
        address liquidator,
        address borrower,
        uint256 repayAmount,
        IOToken oTokenCollateral
    ) internal returns (uint256, uint256) {
        /* Fail if liquidate not allowed */
        uint256 allowed = comptroller.liquidateBorrowAllowed(
            address(this),
            address(oTokenCollateral),
            liquidator,
            borrower,
            repayAmount
        );
        if (allowed != 0) {
            return (
                failOpaque(
                    Error.COMPTROLLER_REJECTION,
                    FailureInfo.LIQUIDATE_COMPTROLLER_REJECTION,
                    allowed
                ),
                0
            );
        }

        /* Verify market's block timestamp equals current block timestamp */
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return (
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.LIQUIDATE_FRESHNESS_CHECK
                ),
                0
            );
        }

        /* Verify oTokenCollateral market's block timestamp equals current block timestamp */
        if (oTokenCollateral.accrualBlockTimestamp() != getBlockTimestamp()) {
            return (
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.LIQUIDATE_COLLATERAL_FRESHNESS_CHECK
                ),
                0
            );
        }

        /* Fail if borrower = liquidator */
        if (borrower == liquidator) {
            return (
                fail(
                    Error.INVALID_ACCOUNT_PAIR,
                    FailureInfo.LIQUIDATE_LIQUIDATOR_IS_BORROWER
                ),
                0
            );
        }

        /* Fail if repayAmount = 0 */
        if (repayAmount == 0) {
            return (
                fail(
                    Error.INVALID_CLOSE_AMOUNT_REQUESTED,
                    FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_ZERO
                ),
                0
            );
        }

        /* Fail if repayAmount = -1 */
        if (repayAmount == type(uint256).max) {
            return (
                fail(
                    Error.INVALID_CLOSE_AMOUNT_REQUESTED,
                    FailureInfo.LIQUIDATE_CLOSE_AMOUNT_IS_UINT_MAX
                ),
                0
            );
        }

        /* Fail if repayBorrow fails */
        (
            uint256 repayBorrowError,
            uint256 actualRepayAmount
        ) = repayBorrowFresh(liquidator, borrower, repayAmount);
        if (repayBorrowError != uint256(Error.NO_ERROR)) {
            return (
                fail(
                    Error(repayBorrowError),
                    FailureInfo.LIQUIDATE_REPAY_BORROW_FRESH_FAILED
                ),
                0
            );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /* We calculate the number of collateral tokens that will be seized */
        (uint256 amountSeizeError, uint256 seizeTokens) = comptroller
            .liquidateCalculateSeizeTokens(
                address(this),
                address(oTokenCollateral),
                actualRepayAmount
            );
        require(
            amountSeizeError == uint256(Error.NO_ERROR),
            "LIQUIDATE_COMPTROLLER_CALCULATE_AMOUNT_SEIZE_FAILED"
        );

        /* Revert if borrower collateral token balance < seizeTokens */
        require(
            oTokenCollateral.balanceOf(borrower) >= seizeTokens,
            "LIQUIDATE_SEIZE_TOO_MUCH"
        );

        // If this is also the collateral, run seizeInternal to avoid re-entrancy, otherwise make an external call
        uint256 seizeError;
        if (address(oTokenCollateral) == address(this)) {
            seizeError = seizeInternal(
                address(this),
                liquidator,
                borrower,
                seizeTokens
            );
        } else {
            seizeError = oTokenCollateral.seize(
                liquidator,
                borrower,
                seizeTokens
            );
        }

        /* Revert if seize tokens fails (since we cannot be sure of side effects) */
        require(seizeError == uint256(Error.NO_ERROR), "token seizure failed");

        /* We emit a LiquidateBorrow event */
        emit LiquidateBorrow(
            liquidator,
            borrower,
            actualRepayAmount,
            address(oTokenCollateral),
            seizeTokens
        );

        /* We call the defense hook */
        // unused function
        // comptroller.liquidateBorrowVerify(address(this), address(oTokenCollateral), liquidator, borrower, actualRepayAmount, seizeTokens);

        return (uint256(Error.NO_ERROR), actualRepayAmount);
    }

    /**
     * @notice Transfers collateral tokens (this market) to the liquidator.
     * @dev Will fail unless called by another oToken during the process of liquidation.
     *  Its absolutely critical to use msg.sender as the borrowed oToken and not a parameter.
     * @param liquidator The account receiving seized collateral
     * @param borrower The account having collateral seized
     * @param seizeTokens The number of oTokens to seize
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function seize(
        address liquidator,
        address borrower,
        uint256 seizeTokens
    ) external override nonReentrant returns (uint256) {
        return seizeInternal(msg.sender, liquidator, borrower, seizeTokens);
    }

    struct SeizeInternalLocalVars {
        MathError mathErr;
        uint256 borrowerTokensNew;
        uint256 liquidatorTokensNew;
        uint256 liquidatorSeizeTokens;
        uint256 protocolSeizeTokens;
        uint256 protocolSeizeAmount;
        uint256 exchangeRateMantissa;
        uint256 totalReservesNew;
        uint256 totalSupplyNew;
    }

    /**
     * @notice Transfers collateral tokens (this market) to the liquidator.
     * @dev Called only during an in-kind liquidation, or by liquidateBorrow during the liquidation of another OToken.
     *  Its absolutely critical to use msg.sender as the seizer oToken and not a parameter.
     * @param seizerToken The contract seizing the collateral (i.e. borrowed oToken)
     * @param liquidator The account receiving seized collateral
     * @param borrower The account having collateral seized
     * @param seizeTokens The number of oTokens to seize
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function seizeInternal(
        address seizerToken,
        address liquidator,
        address borrower,
        uint256 seizeTokens
    ) internal returns (uint256) {
        /* Fail if seize not allowed */
        uint256 allowed = comptroller.seizeAllowed(
            address(this),
            seizerToken,
            liquidator,
            borrower,
            seizeTokens
        );
        if (allowed != 0) {
            return
                failOpaque(
                    Error.COMPTROLLER_REJECTION,
                    FailureInfo.LIQUIDATE_SEIZE_COMPTROLLER_REJECTION,
                    allowed
                );
        }

        /* Fail if borrower = liquidator */
        if (borrower == liquidator) {
            return
                fail(
                    Error.INVALID_ACCOUNT_PAIR,
                    FailureInfo.LIQUIDATE_SEIZE_LIQUIDATOR_IS_BORROWER
                );
        }

        SeizeInternalLocalVars memory vars;

        /*
         * We calculate the new borrower and liquidator token balances, failing on underflow/overflow:
         *  borrowerTokensNew = accountTokens[borrower] - seizeTokens
         *  liquidatorTokensNew = accountTokens[liquidator] + seizeTokens
         */
        (vars.mathErr, vars.borrowerTokensNew) = subUInt(
            accountTokens[borrower],
            seizeTokens
        );
        if (vars.mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.LIQUIDATE_SEIZE_BALANCE_DECREMENT_FAILED,
                    uint256(vars.mathErr)
                );
        }

        vars.protocolSeizeTokens = mul_(
            seizeTokens,
            Exp({mantissa: protocolSeizeShareMantissa})
        );

        vars.liquidatorSeizeTokens = seizeTokens - vars.protocolSeizeTokens;

        (
            vars.mathErr,
            vars.exchangeRateMantissa
        ) = exchangeRateStoredInternal();
        require(vars.mathErr == MathError.NO_ERROR, "exchange rate math error");

        vars.protocolSeizeAmount = mul_ScalarTruncate(
            Exp({mantissa: vars.exchangeRateMantissa}),
            vars.protocolSeizeTokens
        );

        vars.totalReservesNew = totalReserves + vars.protocolSeizeAmount;
        vars.totalSupplyNew = totalSupply - vars.protocolSeizeTokens;

        (vars.mathErr, vars.liquidatorTokensNew) = addUInt(
            accountTokens[liquidator],
            vars.liquidatorSeizeTokens
        );
        if (vars.mathErr != MathError.NO_ERROR) {
            return
                failOpaque(
                    Error.MATH_ERROR,
                    FailureInfo.LIQUIDATE_SEIZE_BALANCE_INCREMENT_FAILED,
                    uint256(vars.mathErr)
                );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /* We write the previously calculated values into storage */
        _updateBoostSupplyBalances(
            borrower,
            accountTokens[borrower],
            vars.borrowerTokensNew
        );
        _updateBoostSupplyBalances(
            liquidator,
            accountTokens[liquidator],
            vars.liquidatorTokensNew
        );

        totalReserves = vars.totalReservesNew;
        totalSupply = vars.totalSupplyNew;
        accountTokens[borrower] = vars.borrowerTokensNew;
        accountTokens[liquidator] = vars.liquidatorTokensNew;

        /* Emit a Transfer event */
        emit Transfer(borrower, liquidator, vars.liquidatorSeizeTokens);
        emit Transfer(borrower, address(this), vars.protocolSeizeTokens);
        emit ReservesAdded(
            address(this),
            vars.protocolSeizeAmount,
            vars.totalReservesNew
        );

        /* We call the defense hook */
        // unused function
        // comptroller.seizeVerify(address(this), seizerToken, liquidator, borrower, seizeTokens);

        return uint256(Error.NO_ERROR);
    }

    /*** Admin Functions ***/
    function unauthorized(FailureInfo info) internal returns (uint) {
        return fail(Error.UNAUTHORIZED, info);
    }

    function setAdmin(address payable _admin) public {
        require(msg.sender == admin, "Unauthorized");
        address oldAdmin = admin;
        admin = _admin;
        emit NewAdmin(oldAdmin, admin);
    }

    /**
     * @notice Begins transfer of admin rights. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
     * @dev Admin function to begin change of admin. The newPendingAdmin must call `_acceptAdmin` to finalize the transfer.
     * @param newPendingAdmin New pending admin.
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setPendingAdmin(address payable newPendingAdmin)
        external
        override
        returns (uint256)
    {
        // Check caller = admin
        if (msg.sender != admin) {
            return unauthorized(FailureInfo.SET_PENDING_ADMIN_OWNER_CHECK);
        }
        // Emit NewPendingAdmin(oldPendingAdmin, newPendingAdmin)
        emit NewPendingAdmin(pendingAdmin, newPendingAdmin);

        // Store pendingAdmin with value newPendingAdmin
        pendingAdmin = newPendingAdmin;

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Accepts transfer of admin rights. msg.sender must be pendingAdmin
     * @dev Admin function for pending admin to accept role and update admin
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _acceptAdmin() external override returns (uint256) {
        // Check caller is pendingAdmin and pendingAdmin ≠ address(0)
        if (msg.sender != pendingAdmin || msg.sender == address(0)) {
            return unauthorized(FailureInfo.ACCEPT_ADMIN_PENDING_ADMIN_CHECK);
        }

        // Save current values for inclusion in log
        address oldAdmin = admin;
        address oldPendingAdmin = pendingAdmin;

        // Store admin with value pendingAdmin
        admin = pendingAdmin;

        // Clear the pending value
        pendingAdmin = payable(address(0));

        emit NewAdmin(oldAdmin, admin);
        emit NewPendingAdmin(oldPendingAdmin, pendingAdmin);

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Sets a new comptroller for the market
     * @dev Admin function to set a new comptroller
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setComptroller(IComptroller newComptroller)
        public
        override
        returns (uint256)
    {
        // Check caller is admin
        if (msg.sender != admin) {
            return unauthorized(FailureInfo.SET_COMPTROLLER_OWNER_CHECK);
        }

        IComptroller oldComptroller = comptroller;
        // Ensure invoke comptroller.isComptroller() returns true
        require(newComptroller.isComptroller(), "marker method returned false");

        // Set market's comptroller to newComptroller
        comptroller = newComptroller;

        // Emit NewComptroller(oldComptroller, newComptroller)
        emit NewComptroller(oldComptroller, newComptroller);

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice accrues interest and sets a new reserve factor for the protocol using _setReserveFactorFresh
     * @dev Admin function to accrue interest and set a new reserve factor
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setReserveFactor(uint256 newReserveFactorMantissa)
        external
        override
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reserve factor change failed.
            return
                fail(
                    Error(error),
                    FailureInfo.SET_RESERVE_FACTOR_ACCRUE_INTEREST_FAILED
                );
        }
        // _setReserveFactorFresh emits reserve-factor-specific logs on errors, so we don't need to.
        return _setReserveFactorFresh(newReserveFactorMantissa);
    }

    /**
     * @notice Sets a new reserve factor for the protocol (*requires fresh interest accrual)
     * @dev Admin function to set a new reserve factor
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setReserveFactorFresh(uint256 newReserveFactorMantissa)
        internal
        returns (uint256)
    {
        // Check caller is admin
        if (msg.sender != admin) {
            return unauthorized(FailureInfo.SET_RESERVE_FACTOR_ADMIN_CHECK);
        }

        // Verify market's block timestamp equals current block timestamp
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.SET_RESERVE_FACTOR_FRESH_CHECK
                );
        }

        // Check newReserveFactor ≤ maxReserveFactor
        if (newReserveFactorMantissa > reserveFactorMaxMantissa) {
            return
                fail(
                    Error.BAD_INPUT,
                    FailureInfo.SET_RESERVE_FACTOR_BOUNDS_CHECK
                );
        }

        uint256 oldReserveFactorMantissa = reserveFactorMantissa;
        reserveFactorMantissa = newReserveFactorMantissa;

        emit NewReserveFactor(
            oldReserveFactorMantissa,
            newReserveFactorMantissa
        );

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice Accrues interest and reduces reserves by transferring from msg.sender
     * @param addAmount Amount of addition to reserves
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _addReservesInternal(uint256 addAmount)
        internal
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
            return
                fail(
                    Error(error),
                    FailureInfo.ADD_RESERVES_ACCRUE_INTEREST_FAILED
                );
        }

        // _addReservesFresh emits reserve-addition-specific logs on errors, so we don't need to.
        (error, ) = _addReservesFresh(addAmount);
        return error;
    }

    /**
     * @notice Add reserves by transferring from caller
     * @dev Requires fresh interest accrual
     * @param addAmount Amount of addition to reserves
     * @return (uint, uint) An error code (0=success, otherwise a failure (see ErrorReporter.sol for details)) and the actual amount added, net token fees
     */
    function _addReservesFresh(uint256 addAmount)
        internal
        returns (uint256, uint256)
    {
        // totalReserves + actualAddAmount
        uint256 totalReservesNew;
        uint256 actualAddAmount;

        // We fail gracefully unless market's block timestamp equals current block timestamp
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return (
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.ADD_RESERVES_FRESH_CHECK
                ),
                actualAddAmount
            );
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        /*
         * We call doTransferIn for the caller and the addAmount
         *  Note: The oToken must handle variations between ERC-20 and NATIVE underlying.
         *  On success, the oToken holds an additional addAmount of cash.
         *  doTransferIn reverts if anything goes wrong, since we can't be sure if side effects occurred.
         *  it returns the amount actually transferred, in case of a fee.
         */

        actualAddAmount = doTransferIn(msg.sender, addAmount);

        /* Reverts on overflow */
        totalReservesNew = totalReserves + actualAddAmount;

        // Store reserves[n+1] = reserves[n] + actualAddAmount
        totalReserves = totalReservesNew;

        /* Emit NewReserves(admin, actualAddAmount, reserves[n+1]) */
        emit ReservesAdded(msg.sender, actualAddAmount, totalReservesNew);

        /* Return (NO_ERROR, actualAddAmount) */
        return (uint256(Error.NO_ERROR), actualAddAmount);
    }

    /**
     * @notice Accrues interest and reduces reserves by transferring to admin
     * @param reduceAmount Amount of reduction to reserves
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _reduceReserves(uint256 reduceAmount)
        external
        override
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted reduce reserves failed.
            return
                fail(
                    Error(error),
                    FailureInfo.REDUCE_RESERVES_ACCRUE_INTEREST_FAILED
                );
        }
        // _reduceReservesFresh emits reserve-reduction-specific logs on errors, so we don't need to.
        return _reduceReservesFresh(reduceAmount);
    }

    /**
     * @notice Reduces reserves by transferring to admin
     * @dev Requires fresh interest accrual
     * @param reduceAmount Amount of reduction to reserves
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _reduceReservesFresh(uint256 reduceAmount)
        internal
        returns (uint256)
    {
        // totalReserves - reduceAmount
        uint256 totalReservesNew;

        // Check caller is admin
        if (msg.sender != admin) {
            return unauthorized(FailureInfo.REDUCE_RESERVES_ADMIN_CHECK);
        }

        // We fail gracefully unless market's block timestamp equals current block timestamp
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.REDUCE_RESERVES_FRESH_CHECK
                );
        }

        // Fail gracefully if protocol has insufficient underlying cash
        if (getCashPrior() < reduceAmount) {
            return
                fail(
                    Error.TOKEN_INSUFFICIENT_CASH,
                    FailureInfo.REDUCE_RESERVES_CASH_NOT_AVAILABLE
                );
        }

        // Check reduceAmount ≤ reserves[n] (totalReserves)
        if (reduceAmount > totalReserves) {
            return
                fail(Error.BAD_INPUT, FailureInfo.REDUCE_RESERVES_VALIDATION);
        }

        /////////////////////////
        // EFFECTS & INTERACTIONS
        // (No safe failures beyond this point)

        // We checked reduceAmount <= totalReserves above, so this should never revert.
        totalReservesNew = totalReserves - reduceAmount;

        // Store reserves[n+1] = reserves[n] - reduceAmount
        totalReserves = totalReservesNew;

        // doTransferOut reverts if anything goes wrong, since we can't be sure if side effects occurred.
        doTransferOut(admin, reduceAmount);

        emit ReservesReduced(admin, reduceAmount, totalReservesNew);

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice accrues interest and updates the interest rate model using _setInterestRateModelFresh
     * @dev Admin function to accrue interest and update the interest rate model
     * @param newInterestRateModel the new interest rate model to use
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setInterestRateModel(IInterestRateModel newInterestRateModel)
        public
        override
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of interest rate model failed
            return
                fail(
                    Error(error),
                    FailureInfo.SET_INTEREST_RATE_MODEL_ACCRUE_INTEREST_FAILED
                );
        }
        // _setInterestRateModelFresh emits interest-rate-model-update-specific logs on errors, so we don't need to.
        return _setInterestRateModelFresh(newInterestRateModel);
    }

    /**
     * @notice updates the interest rate model (*requires fresh interest accrual)
     * @dev Admin function to update the interest rate model
     * @param newInterestRateModel the new interest rate model to use
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setInterestRateModelFresh(IInterestRateModel newInterestRateModel)
        internal
        returns (uint256)
    {
        // Used to store old model for use in the event that is emitted on success
        IInterestRateModel oldInterestRateModel;

        // Check caller is admin
        if (msg.sender != admin) {
            return
                unauthorized(FailureInfo.SET_INTEREST_RATE_MODEL_OWNER_CHECK);
        }

        // We fail gracefully unless market's block timestamp equals current block timestamp
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.SET_INTEREST_RATE_MODEL_FRESH_CHECK
                );
        }

        // Track the market's current interest rate model
        oldInterestRateModel = interestRateModel;

        // Ensure invoke newInterestRateModel.isInterestRateModel() returns true
        require(
            newInterestRateModel.isInterestRateModel(),
            "marker method returned false"
        );

        // Set the interest rate model to newInterestRateModel
        interestRateModel = newInterestRateModel;

        // Emit NewMarketInterestRateModel(oldInterestRateModel, newInterestRateModel)
        emit NewMarketInterestRateModel(
            oldInterestRateModel,
            newInterestRateModel
        );

        return uint256(Error.NO_ERROR);
    }

    /**
     * @notice accrues interest and updates the protocol seize share using _setProtocolSeizeShareFresh
     * @dev Admin function to accrue interest and update the protocol seize share
     * @param newProtocolSeizeShareMantissa the new protocol seize share to use
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setProtocolSeizeShare(uint256 newProtocolSeizeShareMantissa)
        external
        override
        nonReentrant
        returns (uint256)
    {
        uint256 error = accrueInterest();
        if (error != uint256(Error.NO_ERROR)) {
            // accrueInterest emits logs on errors, but on top of that we want to log the fact that an attempted change of protocol seize share failed
            return
                fail(
                    Error(error),
                    FailureInfo.SET_PROTOCOL_SEIZE_SHARE_ACCRUE_INTEREST_FAILED
                );
        }
        // _setProtocolSeizeShareFresh emits protocol-seize-share-update-specific logs on errors, so we don't need to.
        return _setProtocolSeizeShareFresh(newProtocolSeizeShareMantissa);
    }

    /**
     * @notice updates the protocol seize share (*requires fresh interest accrual)
     * @dev Admin function to update the protocol seize share
     * @param newProtocolSeizeShareMantissa the new protocol seize share to use
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _setProtocolSeizeShareFresh(uint256 newProtocolSeizeShareMantissa)
        internal
        returns (uint256)
    {
        // Check caller is admin
        if (msg.sender != admin) {
            return
                unauthorized(FailureInfo.SET_PROTOCOL_SEIZE_SHARE_OWNER_CHECK);
        }

        // We fail gracefully unless market's block timestamp equals current block timestamp
        if (accrualBlockTimestamp != getBlockTimestamp()) {
            return
                fail(
                    Error.MARKET_NOT_FRESH,
                    FailureInfo.SET_PROTOCOL_SEIZE_SHARE_FRESH_CHECK
                );
        }
        // Emit NewProtocolSeizeShareMantissa(oldProtocolSeizeShareMantissa, newProtocolSeizeShareMantissa)
        emit NewProtocolSeizeShare(
            protocolSeizeShareMantissa,
            newProtocolSeizeShareMantissa
        );

        // Set the protocol seize share to newProtocolSeizeShareMantissa
        protocolSeizeShareMantissa = newProtocolSeizeShareMantissa;

        return uint256(Error.NO_ERROR);
    }

    /*** Safe Token ***/

    /**
     * @notice Gets balance of this contract in terms of the underlying
     * @dev This excludes the value of the current message, if any
     * @return The quantity of underlying owned by this contract
     */
    function getCashPrior() internal view virtual returns (uint256);

    /**
     * @dev Performs a transfer in, reverting upon failure. Returns the amount actually transferred to the protocol, in case of a fee.
     *  This may revert due to insufficient balance or insufficient allowance.
     */
    function doTransferIn(address from, uint256 amount)
        internal
        virtual
        returns (uint256);

    /**
     * @dev Performs a transfer out, ideally returning an explanatory error code upon failure tather than reverting.
     *  If caller has not called checked protocol's balance, may revert due to insufficient cash held in the contract.
     *  If caller has checked protocol's balance, and verified it is >= amount, this should not revert in normal conditions.
     */
    function doTransferOut(address payable to, uint256 amount) internal virtual;

    /*** Reentrancy Guard ***/

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     */
    modifier nonReentrant() {
        require(_notEntered, "re-entered");
        _notEntered = false;
        _;
        _notEntered = true; // get a gas-refund post-Istanbul
    }

    function requireNoError(uint256 errCode, string memory message)
        internal
        pure
    {
        unchecked {
            if (errCode == uint256(Error.NO_ERROR)) {
                return;
            }

            bytes memory fullMessage = new bytes(bytes(message).length + 5);
            uint256 i;

            for (i = 0; i < bytes(message).length; i++) {
                fullMessage[i] = bytes(message)[i];
            }

            fullMessage[i + 0] = bytes1(uint8(32));
            fullMessage[i + 1] = bytes1(uint8(40));
            fullMessage[i + 2] = bytes1(uint8(48 + (errCode / 10)));
            fullMessage[i + 3] = bytes1(uint8(48 + (errCode % 10)));
            fullMessage[i + 4] = bytes1(uint8(41));

            require(errCode == uint256(Error.NO_ERROR), string(fullMessage));
        }
    }
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "../interfaces/IEIP20NonStandard.sol";
import "../interfaces/IOToken.sol";
import "../interfaces/IOErc20.sol";

import "../../interfaces/IComptroller.sol";
import "../../interest-rate-models/interfaces/IInterestRateModel.sol";

abstract contract OTokenStorage is IOToken {
    bool public constant override isOToken = true;

    /**
     * @dev Guard variable for re-entrancy checks
     */
    bool internal _notEntered;

    /**
     * @notice EIP-20 token name for this token
     */
    string public override name;

    /**
     * @notice EIP-20 token symbol for this token
     */
    string public override symbol;

    /**
     * @notice EIP-20 token decimals for this token
     */
    uint8 public override decimals;

    /**
     * @notice Maximum borrow rate that can ever be applied (.0005% / block)
     */

    uint internal constant borrowRateMaxMantissa = 0.0005e16;

    /**
     * @notice Maximum fraction of interest that can be set aside for reserves
     */
    uint internal constant reserveFactorMaxMantissa = 1e18;

    /**
     * @notice Administrator for this contract
     */
    address payable public admin;

    /**
     * @notice Pending administrator for this contract
     */
    address payable public pendingAdmin;

    /**
     * @notice Contract which oversees inter-oToken operations
     */
    IComptroller public override comptroller;

    /**
     * @notice Model which tells what the current interest rate should be
     */
    IInterestRateModel public interestRateModel;

    /**
     * @notice Initial exchange rate used when minting the first OTokens (used when totalSupply = 0)
     */
    uint internal initialExchangeRateMantissa;

    /**
     * @notice Fraction of interest currently set aside for reserves
     */
    uint public override reserveFactorMantissa;

    /**
     * @notice Block number that interest was last accrued at
     */
    uint public override accrualBlockTimestamp;

    /**
     * @notice Accumulator of the total earned interest rate since the opening of the market
     */
    uint public override borrowIndex;

    /**
     * @notice Total amount of outstanding borrows of the underlying in this market
     */
    uint public override totalBorrows;

    /**
     * @notice Total amount of reserves of the underlying held in this market
     */
    uint public totalReserves;

    /**
     * @notice Total number of tokens in circulation
     */
    uint public override totalSupply;

    /**
     * @notice Official record of token balances for each account
     */
    mapping (address => uint) internal accountTokens;

    /**
     * @notice Approved token transfer amounts on behalf of others
     */
    mapping (address => mapping (address => uint)) internal transferAllowances;

    /**
     * @notice Container for borrow balance information
     * @member principal Total balance (with accrued interest), after applying the most recent balance-changing action
     * @member interestIndex Global borrowIndex as of the most recent balance-changing action
     */
    struct BorrowSnapshot {
        uint principal;
        uint interestIndex;
    }

    /**
     * @notice Mapping of account addresses to outstanding borrow balances
     */
    mapping(address => BorrowSnapshot) internal accountBorrows;

    /**
     * @notice Share of seized collateral that is added to reserves
     */
    uint public protocolSeizeShareMantissa;

}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

/**
 * @title ERC 20 Token Standard Interface
 *  https://eips.ethereum.org/EIPS/eip-20
 */
interface IEIP20 {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);

    /**
      * @notice Get the total number of tokens in circulation
      * @return The supply of tokens
      */
    function totalSupply() external view returns (uint256);

    /**
     * @notice Gets the balance of the specified address
     * @param owner The address from which the balance will be retrieved
     * @return balance The balance
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    /**
      * @notice Transfer `amount` tokens from `msg.sender` to `dst`
      * @param dst The address of the destination account
      * @param amount The number of tokens to transfer
      * @return success Whether or not the transfer succeeded
      */
    function transfer(address dst, uint256 amount) external returns (bool success);

    /**
      * @notice Transfer `amount` tokens from `src` to `dst`
      * @param src The address of the source account
      * @param dst The address of the destination account
      * @param amount The number of tokens to transfer
      * @return success Whether or not the transfer succeeded
      */
    function transferFrom(address src, address dst, uint256 amount) external returns (bool success);

    /**
      * @notice Approve `spender` to transfer up to `amount` from `src`
      * @dev This will overwrite the approval amount for `spender`
      *  and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
      * @param spender The address of the account which may transfer tokens
      * @param amount The number of tokens that are approved (-1 means infinite)
      * @return success Whether or not the approval succeeded
      */
    function approve(address spender, uint256 amount) external returns (bool success);

    /**
      * @notice Get the current allowance from `owner` for `spender`
      * @param owner The address of the account which owns the tokens to be spent
      * @param spender The address of the account which may transfer tokens
      * @return remaining The number of tokens allowed to be spent (-1 means infinite)
      */
    function allowance(address owner, address spender) external view returns (uint256 remaining);

    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

/**
 * @title IEIP20NonStandard
 * @dev Version of ERC20 with no return values for `transfer` and `transferFrom`
 *  See https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
 */
interface IEIP20NonStandard {

    /**
     * @notice Get the total number of tokens in circulation
     * @return The supply of tokens
     */
    function totalSupply() external view returns (uint256);

    /**
     * @notice Gets the balance of the specified address
     * @param owner The address from which the balance will be retrieved
     * @return balance The balance
     */
    function balanceOf(address owner) external view returns (uint256 balance);

    ///
    /// !!!!!!!!!!!!!!
    /// !!! NOTICE !!! `transfer` does not return a value, in violation of the ERC-20 specification
    /// !!!!!!!!!!!!!!
    ///

    /**
      * @notice Transfer `amount` tokens from `msg.sender` to `dst`
      * @param dst The address of the destination account
      * @param amount The number of tokens to transfer
      */
    function transfer(address dst, uint256 amount) external;

    ///
    /// !!!!!!!!!!!!!!
    /// !!! NOTICE !!! `transferFrom` does not return a value, in violation of the ERC-20 specification
    /// !!!!!!!!!!!!!!
    ///

    /**
      * @notice Transfer `amount` tokens from `src` to `dst`
      * @param src The address of the source account
      * @param dst The address of the destination account
      * @param amount The number of tokens to transfer
      */
    function transferFrom(address src, address dst, uint256 amount) external;

    /**
      * @notice Approve `spender` to transfer up to `amount` from `src`
      * @dev This will overwrite the approval amount for `spender`
      *  and is subject to issues noted [here](https://eips.ethereum.org/EIPS/eip-20#approve)
      * @param spender The address of the account which may transfer tokens
      * @param amount The number of tokens that are approved
      * @return success Whether or not the approval succeeded
      */
    function approve(address spender, uint256 amount) external returns (bool success);

    /**
      * @notice Get the current allowance from `owner` for `spender`
      * @param owner The address of the account which owns the tokens to be spent
      * @param spender The address of the account which may transfer tokens
      * @return remaining The number of tokens allowed to be spent
      */
    function allowance(address owner, address spender) external view returns (uint256 remaining);

    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "./IEIP20NonStandard.sol";
import "./IOToken.sol";

interface IOErc20 {

    /*** User Interface ***/

    function mint(uint mintAmount) external;
    function redeem(uint redeemTokens) external;
    function redeemUnderlying(uint redeemAmount) external;
    function borrow(uint borrowAmount) external;
    function repayBorrow(uint repayAmount) external;
    function repayBorrowBehalf(address borrower, uint repayAmount) external;
    function liquidateBorrow(address borrower, uint repayAmount, IOToken oTokenCollateral) external;
    function sweepToken(IEIP20NonStandard token) external;

    function underlying() external view returns(address);

    /*** Admin Functions ***/

    function _addReserves(uint addAmount) external returns (uint);
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "../../interfaces/IComptroller.sol";
import "../../interest-rate-models/interfaces/IInterestRateModel.sol";
import "./IEIP20NonStandard.sol";
import "./IEIP20.sol";

interface IOToken is IEIP20{
    /**
     * @notice Indicator that this is a OToken contract (for inspection)
     */
    function isOToken() external view returns(bool);


    /*** Market Events ***/

    /**
     * @notice Event emitted when interest is accrued
     */
    event AccrueInterest(uint cashPrior, uint interestAccumulated, uint borrowIndex, uint totalBorrows);

    /**
     * @notice Event emitted when tokens are minted
     */
    event Mint(address minter, uint mintAmount, uint mintTokens);

    /**
     * @notice Event emitted when tokens are redeemed
     */
    event Redeem(address redeemer, uint redeemAmount, uint redeemTokens);

    /**
     * @notice Event emitted when underlying is borrowed
     */
    event Borrow(address borrower, uint borrowAmount, uint accountBorrows, uint totalBorrows);

    /**
     * @notice Event emitted when a borrow is repaid
     */
    event RepayBorrow(address payer, address borrower, uint repayAmount, uint accountBorrows, uint totalBorrows);

    /**
     * @notice Event emitted when a borrow is liquidated
     */
    event LiquidateBorrow(address liquidator, address borrower, uint repayAmount, address oTokenCollateral, uint seizeTokens);


    /*** Admin Events ***/

    /**
     * @notice Event emitted when pendingAdmin is changed
     */
    event NewPendingAdmin(address oldPendingAdmin, address newPendingAdmin);

    /**
     * @notice Event emitted when pendingAdmin is accepted, which means admin is updated
     */
    event NewAdmin(address oldAdmin, address newAdmin);

    /**
     * @notice Event emitted when comptroller is changed
     */
    event NewComptroller(IComptroller oldComptroller, IComptroller newComptroller);

    /**
     * @notice Event emitted when interestRateModel is changed
     */
    event NewMarketInterestRateModel(IInterestRateModel oldInterestRateModel, IInterestRateModel newInterestRateModel);

    /**
     * @notice Event emitted when the reserve factor is changed
     */
    event NewReserveFactor(uint oldReserveFactorMantissa, uint newReserveFactorMantissa);

    /**
     * @notice Event emitted when the protocol seize share is changed
     */
    event NewProtocolSeizeShare(uint oldProtocolSeizeShareMantissa, uint newProtocolSeizeShareMantissa);

    /**
     * @notice Event emitted when the reserves are added
     */
    event ReservesAdded(address benefactor, uint addAmount, uint newTotalReserves);

    /**
     * @notice Event emitted when the reserves are reduced
     */
    event ReservesReduced(address admin, uint reduceAmount, uint newTotalReserves);

    function accrualBlockTimestamp() external returns(uint256);

    /*** User Interface ***/
    function balanceOfUnderlying(address owner) external returns (uint);
    function getAccountSnapshot(address account) external view returns (uint, uint, uint, uint);
    function borrowRatePerTimestamp() external view returns (uint);
    function supplyRatePerTimestamp() external view returns (uint);
    function totalBorrowsCurrent() external returns (uint);
    function borrowBalanceCurrent(address account) external returns (uint);
    function borrowBalanceStored(address account) external view returns (uint);
    function exchangeRateCurrent() external returns (uint);
    function exchangeRateStored() external view returns (uint);
    function getCash() external view returns (uint);
    function accrueInterest() external returns (uint);
    function seize(address liquidator, address borrower, uint seizeTokens) external returns (uint);

    function totalBorrows() external view returns(uint);
    function comptroller() external view returns(IComptroller);
    function borrowIndex() external view returns(uint);
    function reserveFactorMantissa() external view returns(uint);


    /*** Admin Functions ***/

    function _setPendingAdmin(address payable newPendingAdmin) external returns (uint);
    function _acceptAdmin() external returns (uint);
    function _setComptroller(IComptroller newComptroller) external returns (uint);
    function _setReserveFactor(uint newReserveFactorMantissa) external returns (uint);
    function _reduceReserves(uint reduceAmount) external returns (uint);
    function _setInterestRateModel(IInterestRateModel newInterestRateModel) external returns (uint);
    function _setProtocolSeizeShare(uint newProtocolSeizeShareMantissa) external returns (uint);
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "./abstract/OToken.sol";

/**
 * @title 0VIX's ONative Contract
 * @notice OToken which wraps Native
 * @author 0VIX
 */
contract ONative is OToken {

    bool public isInit = true;  // init lock, only proxy can run init

    /**
     * @notice Construct a new ONative money market
     * @param comptroller_ The address of the Comptroller
     * @param interestRateModel_ The address of the interest rate model
     * @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
     * @param name_ ERC-20 name of this token
     * @param symbol_ ERC-20 symbol of this token
     * @param decimals_ ERC-20 decimal precision of this token
     * @param admin_ Address of the administrator of this token
     */
    function init(
        IComptroller comptroller_,
        IInterestRateModel interestRateModel_,
        uint256 initialExchangeRateMantissa_,
        string memory name_,
        string memory symbol_,
        uint8 decimals_,
        address payable admin_
    ) public {
        require(!isInit,"init not possible");
        isInit = true;
        // Creator of the contract is admin during initialization
        admin = payable(msg.sender);

        super.initialize(
            comptroller_,
            interestRateModel_,
            initialExchangeRateMantissa_,
            name_,
            symbol_,
            decimals_
        );

        // Set the proper admin now that initialization is done
        admin = admin_;
    }

    /*** User Interface ***/

    /**
     * @notice Sender supplies assets into the market and receives oTokens in exchange
     * @dev Reverts upon any failure
     */
    function mint() external payable {
        (uint256 err, ) = mintInternal(msg.value);
        requireNoError(err, "mint failed");
    }

    /**
     * @notice Sender redeems oTokens in exchange for the underlying asset
     * @dev Accrues interest whether or not the operation succeeds, unless reverted
     * @param redeemTokens The number of oTokens to redeem into underlying
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function redeem(uint256 redeemTokens) external returns (uint256) {
        return redeemInternal(redeemTokens);
    }

    /**
     * @notice Sender redeems oTokens in exchange for a specified amount of underlying asset
     * @dev Accrues interest whether or not the operation succeeds, unless reverted
     * @param redeemAmount The amount of underlying to redeem
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function redeemUnderlying(uint256 redeemAmount) external returns (uint256) {
        return redeemUnderlyingInternal(redeemAmount);
    }

    /**
     * @notice Sender borrows assets from the protocol to their own address
     * @param borrowAmount The amount of the underlying asset to borrow
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function borrow(uint256 borrowAmount) external returns (uint256) {
        return borrowInternal(borrowAmount);
    }

    /**
     * @notice Sender repays their own borrow
     * @dev Reverts upon any failure
     */
    function repayBorrow() external payable {
        (uint256 err, ) = repayBorrowInternal(msg.value);
        requireNoError(err, "repayBorrow failed");
    }

    /**
     * @notice Sender repays a borrow belonging to borrower
     * @dev Reverts upon any failure
     * @param borrower the account with the debt being payed off
     */
    function repayBorrowBehalf(address borrower) external payable {
        (uint256 err, ) = repayBorrowBehalfInternal(borrower, msg.value);
        requireNoError(err, "repayBorrowBehalf failed");
    }

    /**
     * @notice The sender liquidates the borrowers collateral.
     *  The collateral seized is transferred to the liquidator.
     * @dev Reverts upon any failure
     * @param borrower The borrower of this oToken to be liquidated
     * @param oTokenCollateral The market in which to seize collateral from the borrower
     */
    function liquidateBorrow(address borrower, IOToken oTokenCollateral)
        external
        payable
    {
        (uint256 err, ) = liquidateBorrowInternal(
            borrower,
            msg.value,
            oTokenCollateral
        );
        requireNoError(err, "liquidateBorrow failed");
    }

    /**
     * @notice The sender adds to reserves.
     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
     */
    function _addReserves() external payable returns (uint256) {
        return _addReservesInternal(msg.value);
    }

    /**
     * @notice Send Native coin to ONative to mint
     */
    receive() external payable {
        (uint256 err, ) = mintInternal(msg.value);
        requireNoError(err, "mint failed");
    }

    /*** Safe Token ***/

    /**
     * @notice Gets balance of this contract in terms of Native, before this message
     * @dev This excludes the value of the current message, if any
     * @return The quantity of Native owned by this contract
     */
    function getCashPrior() internal view override returns (uint256) {
        (MathError err, uint256 startingBalance) = subUInt(
            address(this).balance,
            msg.value
        );
        require(err == MathError.NO_ERROR);
        return startingBalance;
    }

    /**
     * @notice Perform the actual transfer in, which is a no-op
     * @param from Address sending the Native
     * @param amount Amount of Native being sent
     * @return The actual amount of Native transferred
     */
    function doTransferIn(address from, uint256 amount)
        internal override
        returns (uint256)
    {
        // Sanity checks
        require(msg.sender == from, "sender mismatch");
        require(msg.value == amount, "value mismatch");
        return amount;
    }

    function doTransferOut(address payable to, uint256 amount) internal override {
        /* Send the Native, with minimal gas and revert on failure */
        to.transfer(amount);
    }

}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "./otokens/interfaces/IOToken.sol";

abstract contract PriceOracle {
    /// @notice Indicator that this is a PriceOracle contract (for inspection)
    bool public constant isPriceOracle = true;

    /**
      * @notice Get the underlying price of a oToken asset
      * @param oToken The oToken to get the underlying price of
      * @return The underlying asset price mantissa (scaled by 1e18).
      *  Zero means the price is unavailable.
      */
    function getUnderlyingPrice(IOToken oToken) external virtual view returns (uint);
}

//SPDX-License-Identifier: MIT
pragma solidity 0.8.4;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

interface IBoostManager {
    function updateBoostBasis(address user)
        external
        returns (bool);

    function updateBoostSupplyBalances(
        address market,
        address user,
        uint256 oldBalance,
        uint256 newBalance
    ) external;

    function updateBoostBorrowBalances(
        address market,
        address user,
        uint256 oldBalance,
        uint256 newBalance
    ) external;

    function boostedSupplyBalanceOf(address market, address user)
        external
        view
        returns (uint256);

    function boostedBorrowBalanceOf(address market, address user)
        external
        view
        returns (uint256);

    function boostedTotalSupply(address market) external view returns (uint256);

    function boostedTotalBorrows(address market)
        external
        view
        returns (uint256);

    function setAuthorized(address addr, bool flag) external;

    function setVeOVIX(IERC20 ve) external;

    function isAuthorized(address addr) external view returns (bool);
}

{
  "optimizer": {
    "enabled": true,
    "runs": 10
  },
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "devdoc",
        "userdoc",
        "metadata",
        "abi"
      ]
    }
  },
  "libraries": {}
}

• No Contract Security Audit Submitted- Submit Audit Here

[{"inputs":[{"internalType":"contract ONative","name":"oNative_","type":"address"}],"stateMutability":"nonpayable","type":"constructor"},{"inputs":[],"name":"oNative","outputs":[{"internalType":"contract ONative","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"borrower","type":"address"}],"name":"repayBehalf","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[{"internalType":"address","name":"borrower","type":"address"},{"internalType":"contract ONative","name":"oNative_","type":"address"}],"name":"repayBehalfExplicit","outputs":[],"stateMutability":"payable","type":"function"}]

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

000000000000000000000000ee1727f5074e747716637e1776b7f7c7133f16b1

-----Decoded View---------------
Arg [0] : oNative_ (address): 0xee1727f5074E747716637e1776B7F7C7133f16b1

-----Encoded View---------------
1 Constructor Arguments found :
Arg [0] : 000000000000000000000000ee1727f5074e747716637e1776b7f7c7133f16b1