// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;
/// @notice Modern and gas efficient ERC20 + EIP-2612 implementation.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/tokens/ERC20.sol)
/// @author Modified from Uniswap (https://github.com/Uniswap/uniswap-v2-core/blob/master/contracts/UniswapV2ERC20.sol)
/// @dev Do not manually set balances without updating totalSupply, as the sum of all user balances must not exceed it.
abstract contract ERC20 {
    /*//////////////////////////////////////////////////////////////
                                 EVENTS
    //////////////////////////////////////////////////////////////*/
    event Transfer(address indexed from, address indexed to, uint256 amount);
    event Approval(address indexed owner, address indexed spender, uint256 amount);
    /*//////////////////////////////////////////////////////////////
                            METADATA STORAGE
    //////////////////////////////////////////////////////////////*/
    string public name;
    string public symbol;
    uint8 public immutable decimals;
    /*//////////////////////////////////////////////////////////////
                              ERC20 STORAGE
    //////////////////////////////////////////////////////////////*/
    uint256 public totalSupply;
    mapping(address => uint256) public balanceOf;
    mapping(address => mapping(address => uint256)) public allowance;
    /*//////////////////////////////////////////////////////////////
                            EIP-2612 STORAGE
    //////////////////////////////////////////////////////////////*/
    uint256 internal immutable INITIAL_CHAIN_ID;
    bytes32 internal immutable INITIAL_DOMAIN_SEPARATOR;
    mapping(address => uint256) public nonces;
    /*//////////////////////////////////////////////////////////////
                               CONSTRUCTOR
    //////////////////////////////////////////////////////////////*/
    constructor(
        string memory _name,
        string memory _symbol,
        uint8 _decimals
    ) {
        name = _name;
        symbol = _symbol;
        decimals = _decimals;
        INITIAL_CHAIN_ID = block.chainid;
        INITIAL_DOMAIN_SEPARATOR = computeDomainSeparator();
    }
    /*//////////////////////////////////////////////////////////////
                               ERC20 LOGIC
    //////////////////////////////////////////////////////////////*/
    function approve(address spender, uint256 amount) public virtual returns (bool) {
        allowance[msg.sender][spender] = amount;
        emit Approval(msg.sender, spender, amount);
        return true;
    }
    function transfer(address to, uint256 amount) public virtual returns (bool) {
        balanceOf[msg.sender] -= amount;
        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }
        emit Transfer(msg.sender, to, amount);
        return true;
    }
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual returns (bool) {
        uint256 allowed = allowance[from][msg.sender]; // Saves gas for limited approvals.
        if (allowed != type(uint256).max) allowance[from][msg.sender] = allowed - amount;
        balanceOf[from] -= amount;
        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }
        emit Transfer(from, to, amount);
        return true;
    }
    /*//////////////////////////////////////////////////////////////
                             EIP-2612 LOGIC
    //////////////////////////////////////////////////////////////*/
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public virtual {
        require(deadline >= block.timestamp, "PERMIT_DEADLINE_EXPIRED");
        // Unchecked because the only math done is incrementing
        // the owner's nonce which cannot realistically overflow.
        unchecked {
            address recoveredAddress = ecrecover(
                keccak256(
                    abi.encodePacked(
                        "\\x19\\x01",
                        DOMAIN_SEPARATOR(),
                        keccak256(
                            abi.encode(
                                keccak256(
                                    "Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)"
                                ),
                                owner,
                                spender,
                                value,
                                nonces[owner]++,
                                deadline
                            )
                        )
                    )
                ),
                v,
                r,
                s
            );
            require(recoveredAddress != address(0) && recoveredAddress == owner, "INVALID_SIGNER");
            allowance[recoveredAddress][spender] = value;
        }
        emit Approval(owner, spender, value);
    }
    function DOMAIN_SEPARATOR() public view virtual returns (bytes32) {
        return block.chainid == INITIAL_CHAIN_ID ? INITIAL_DOMAIN_SEPARATOR : computeDomainSeparator();
    }
    function computeDomainSeparator() internal view virtual returns (bytes32) {
        return
            keccak256(
                abi.encode(
                    keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
                    keccak256(bytes(name)),
                    keccak256("1"),
                    block.chainid,
                    address(this)
                )
            );
    }
    /*//////////////////////////////////////////////////////////////
                        INTERNAL MINT/BURN LOGIC
    //////////////////////////////////////////////////////////////*/
    function _mint(address to, uint256 amount) internal virtual {
        totalSupply += amount;
        // Cannot overflow because the sum of all user
        // balances can't exceed the max uint256 value.
        unchecked {
            balanceOf[to] += amount;
        }
        emit Transfer(address(0), to, amount);
    }
    function _burn(address from, uint256 amount) internal virtual {
        balanceOf[from] -= amount;
        // Cannot underflow because a user's balance
        // will never be larger than the total supply.
        unchecked {
            totalSupply -= amount;
        }
        emit Transfer(from, address(0), amount);
    }
}
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;
import {ERC20} from "../tokens/ERC20.sol";
/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/
    function safeTransferETH(address to, uint256 amount) internal {
        bool success;
        /// @solidity memory-safe-assembly
        assembly {
            // Transfer the ETH and store if it succeeded or not.
            success := call(gas(), to, amount, 0, 0, 0, 0)
        }
        require(success, "ETH_TRANSFER_FAILED");
    }
    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/
    function safeTransferFrom(
        ERC20 token,
        address from,
        address to,
        uint256 amount
    ) internal {
        bool success;
        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), from) // Append the "from" argument.
            mstore(add(freeMemoryPointer, 36), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument.
            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)
            )
        }
        require(success, "TRANSFER_FROM_FAILED");
    }
    function safeTransfer(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;
        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.
            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }
        require(success, "TRANSFER_FAILED");
    }
    function safeApprove(
        ERC20 token,
        address to,
        uint256 amount
    ) internal {
        bool success;
        /// @solidity memory-safe-assembly
        assembly {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), to) // Append the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument.
            success := and(
                // Set success to whether the call reverted, if not we check it either
                // returned exactly 1 (can't just be non-zero data), or had no return data.
                or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize())),
                // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
                // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
                // Counterintuitively, this call must be positioned second to the or() call in the
                // surrounding and() call or else returndatasize() will be zero during the computation.
                call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)
            )
        }
        require(success, "APPROVE_FAILED");
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;
import {ERC20} from "solmate/tokens/ERC20.sol";
import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
import {PermitHash} from "./libraries/PermitHash.sol";
import {SignatureVerification} from "./libraries/SignatureVerification.sol";
import {EIP712} from "./EIP712.sol";
import {IAllowanceTransfer} from "../src/interfaces/IAllowanceTransfer.sol";
import {SignatureExpired, InvalidNonce} from "./PermitErrors.sol";
import {Allowance} from "./libraries/Allowance.sol";
contract AllowanceTransfer is IAllowanceTransfer, EIP712 {
    using SignatureVerification for bytes;
    using SafeTransferLib for ERC20;
    using PermitHash for PermitSingle;
    using PermitHash for PermitBatch;
    using Allowance for PackedAllowance;
    /// @notice Maps users to tokens to spender addresses and information about the approval on the token
    /// @dev Indexed in the order of token owner address, token address, spender address
    /// @dev The stored word saves the allowed amount, expiration on the allowance, and nonce
    mapping(address => mapping(address => mapping(address => PackedAllowance))) public allowance;
    /// @inheritdoc IAllowanceTransfer
    function approve(address token, address spender, uint160 amount, uint48 expiration) external {
        PackedAllowance storage allowed = allowance[msg.sender][token][spender];
        allowed.updateAmountAndExpiration(amount, expiration);
        emit Approval(msg.sender, token, spender, amount, expiration);
    }
    /// @inheritdoc IAllowanceTransfer
    function permit(address owner, PermitSingle memory permitSingle, bytes calldata signature) external {
        if (block.timestamp > permitSingle.sigDeadline) revert SignatureExpired(permitSingle.sigDeadline);
        // Verify the signer address from the signature.
        signature.verify(_hashTypedData(permitSingle.hash()), owner);
        _updateApproval(permitSingle.details, owner, permitSingle.spender);
    }
    /// @inheritdoc IAllowanceTransfer
    function permit(address owner, PermitBatch memory permitBatch, bytes calldata signature) external {
        if (block.timestamp > permitBatch.sigDeadline) revert SignatureExpired(permitBatch.sigDeadline);
        // Verify the signer address from the signature.
        signature.verify(_hashTypedData(permitBatch.hash()), owner);
        address spender = permitBatch.spender;
        unchecked {
            uint256 length = permitBatch.details.length;
            for (uint256 i = 0; i < length; ++i) {
                _updateApproval(permitBatch.details[i], owner, spender);
            }
        }
    }
    /// @inheritdoc IAllowanceTransfer
    function transferFrom(address from, address to, uint160 amount, address token) external {
        _transfer(from, to, amount, token);
    }
    /// @inheritdoc IAllowanceTransfer
    function transferFrom(AllowanceTransferDetails[] calldata transferDetails) external {
        unchecked {
            uint256 length = transferDetails.length;
            for (uint256 i = 0; i < length; ++i) {
                AllowanceTransferDetails memory transferDetail = transferDetails[i];
                _transfer(transferDetail.from, transferDetail.to, transferDetail.amount, transferDetail.token);
            }
        }
    }
    /// @notice Internal function for transferring tokens using stored allowances
    /// @dev Will fail if the allowed timeframe has passed
    function _transfer(address from, address to, uint160 amount, address token) private {
        PackedAllowance storage allowed = allowance[from][token][msg.sender];
        if (block.timestamp > allowed.expiration) revert AllowanceExpired(allowed.expiration);
        uint256 maxAmount = allowed.amount;
        if (maxAmount != type(uint160).max) {
            if (amount > maxAmount) {
                revert InsufficientAllowance(maxAmount);
            } else {
                unchecked {
                    allowed.amount = uint160(maxAmount) - amount;
                }
            }
        }
        // Transfer the tokens from the from address to the recipient.
        ERC20(token).safeTransferFrom(from, to, amount);
    }
    /// @inheritdoc IAllowanceTransfer
    function lockdown(TokenSpenderPair[] calldata approvals) external {
        address owner = msg.sender;
        // Revoke allowances for each pair of spenders and tokens.
        unchecked {
            uint256 length = approvals.length;
            for (uint256 i = 0; i < length; ++i) {
                address token = approvals[i].token;
                address spender = approvals[i].spender;
                allowance[owner][token][spender].amount = 0;
                emit Lockdown(owner, token, spender);
            }
        }
    }
    /// @inheritdoc IAllowanceTransfer
    function invalidateNonces(address token, address spender, uint48 newNonce) external {
        uint48 oldNonce = allowance[msg.sender][token][spender].nonce;
        if (newNonce <= oldNonce) revert InvalidNonce();
        // Limit the amount of nonces that can be invalidated in one transaction.
        unchecked {
            uint48 delta = newNonce - oldNonce;
            if (delta > type(uint16).max) revert ExcessiveInvalidation();
        }
        allowance[msg.sender][token][spender].nonce = newNonce;
        emit NonceInvalidation(msg.sender, token, spender, newNonce, oldNonce);
    }
    /// @notice Sets the new values for amount, expiration, and nonce.
    /// @dev Will check that the signed nonce is equal to the current nonce and then incrememnt the nonce value by 1.
    /// @dev Emits a Permit event.
    function _updateApproval(PermitDetails memory details, address owner, address spender) private {
        uint48 nonce = details.nonce;
        address token = details.token;
        uint160 amount = details.amount;
        uint48 expiration = details.expiration;
        PackedAllowance storage allowed = allowance[owner][token][spender];
        if (allowed.nonce != nonce) revert InvalidNonce();
        allowed.updateAll(amount, expiration, nonce);
        emit Permit(owner, token, spender, amount, expiration, nonce);
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;
/// @notice EIP712 helpers for permit2
/// @dev Maintains cross-chain replay protection in the event of a fork
/// @dev Reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/utils/cryptography/EIP712.sol
contract EIP712 {
    // Cache the domain separator as an immutable value, but also store the chain id that it
    // corresponds to, in order to invalidate the cached domain separator if the chain id changes.
    bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
    uint256 private immutable _CACHED_CHAIN_ID;
    bytes32 private constant _HASHED_NAME = keccak256("Permit2");
    bytes32 private constant _TYPE_HASH =
        keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
    constructor() {
        _CACHED_CHAIN_ID = block.chainid;
        _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME);
    }
    /// @notice Returns the domain separator for the current chain.
    /// @dev Uses cached version if chainid and address are unchanged from construction.
    function DOMAIN_SEPARATOR() public view returns (bytes32) {
        return block.chainid == _CACHED_CHAIN_ID
            ? _CACHED_DOMAIN_SEPARATOR
            : _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME);
    }
    /// @notice Builds a domain separator using the current chainId and contract address.
    function _buildDomainSeparator(bytes32 typeHash, bytes32 nameHash) private view returns (bytes32) {
        return keccak256(abi.encode(typeHash, nameHash, block.chainid, address(this)));
    }
    /// @notice Creates an EIP-712 typed data hash
    function _hashTypedData(bytes32 dataHash) internal view returns (bytes32) {
        return keccak256(abi.encodePacked("\\x19\\x01", DOMAIN_SEPARATOR(), dataHash));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;
import {SignatureTransfer} from "./SignatureTransfer.sol";
import {AllowanceTransfer} from "./AllowanceTransfer.sol";
/// @notice Permit2 handles signature-based transfers in SignatureTransfer and allowance-based transfers in AllowanceTransfer.
/// @dev Users must approve Permit2 before calling any of the transfer functions.
contract Permit2 is SignatureTransfer, AllowanceTransfer {
// Permit2 unifies the two contracts so users have maximal flexibility with their approval.
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;
/// @notice Shared errors between signature based transfers and allowance based transfers.
/// @notice Thrown when validating an inputted signature that is stale
/// @param signatureDeadline The timestamp at which a signature is no longer valid
error SignatureExpired(uint256 signatureDeadline);
/// @notice Thrown when validating that the inputted nonce has not been used
error InvalidNonce();
// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;
import {ISignatureTransfer} from "./interfaces/ISignatureTransfer.sol";
import {SignatureExpired, InvalidNonce} from "./PermitErrors.sol";
import {ERC20} from "solmate/tokens/ERC20.sol";
import {SafeTransferLib} from "solmate/utils/SafeTransferLib.sol";
import {SignatureVerification} from "./libraries/SignatureVerification.sol";
import {PermitHash} from "./libraries/PermitHash.sol";
import {EIP712} from "./EIP712.sol";
contract SignatureTransfer is ISignatureTransfer, EIP712 {
    using SignatureVerification for bytes;
    using SafeTransferLib for ERC20;
    using PermitHash for PermitTransferFrom;
    using PermitHash for PermitBatchTransferFrom;
    /// @inheritdoc ISignatureTransfer
    mapping(address => mapping(uint256 => uint256)) public nonceBitmap;
    /// @inheritdoc ISignatureTransfer
    function permitTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external {
        _permitTransferFrom(permit, transferDetails, owner, permit.hash(), signature);
    }
    /// @inheritdoc ISignatureTransfer
    function permitWitnessTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes32 witness,
        string calldata witnessTypeString,
        bytes calldata signature
    ) external {
        _permitTransferFrom(
            permit, transferDetails, owner, permit.hashWithWitness(witness, witnessTypeString), signature
        );
    }
    /// @notice Transfers a token using a signed permit message.
    /// @dev If to is the zero address, the tokens are sent to the spender.
    /// @param permit The permit data signed over by the owner
    /// @param dataHash The EIP-712 hash of permit data to include when checking signature
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails The spender's requested transfer details for the permitted token
    /// @param signature The signature to verify
    function _permitTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes32 dataHash,
        bytes calldata signature
    ) private {
        uint256 requestedAmount = transferDetails.requestedAmount;
        if (block.timestamp > permit.deadline) revert SignatureExpired(permit.deadline);
        if (requestedAmount > permit.permitted.amount) revert InvalidAmount(permit.permitted.amount);
        _useUnorderedNonce(owner, permit.nonce);
        signature.verify(_hashTypedData(dataHash), owner);
        ERC20(permit.permitted.token).safeTransferFrom(owner, transferDetails.to, requestedAmount);
    }
    /// @inheritdoc ISignatureTransfer
    function permitTransferFrom(
        PermitBatchTransferFrom memory permit,
        SignatureTransferDetails[] calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external {
        _permitTransferFrom(permit, transferDetails, owner, permit.hash(), signature);
    }
    /// @inheritdoc ISignatureTransfer
    function permitWitnessTransferFrom(
        PermitBatchTransferFrom memory permit,
        SignatureTransferDetails[] calldata transferDetails,
        address owner,
        bytes32 witness,
        string calldata witnessTypeString,
        bytes calldata signature
    ) external {
        _permitTransferFrom(
            permit, transferDetails, owner, permit.hashWithWitness(witness, witnessTypeString), signature
        );
    }
    /// @notice Transfers tokens using a signed permit messages
    /// @dev If to is the zero address, the tokens are sent to the spender
    /// @param permit The permit data signed over by the owner
    /// @param dataHash The EIP-712 hash of permit data to include when checking signature
    /// @param owner The owner of the tokens to transfer
    /// @param signature The signature to verify
    function _permitTransferFrom(
        PermitBatchTransferFrom memory permit,
        SignatureTransferDetails[] calldata transferDetails,
        address owner,
        bytes32 dataHash,
        bytes calldata signature
    ) private {
        uint256 numPermitted = permit.permitted.length;
        if (block.timestamp > permit.deadline) revert SignatureExpired(permit.deadline);
        if (numPermitted != transferDetails.length) revert LengthMismatch();
        _useUnorderedNonce(owner, permit.nonce);
        signature.verify(_hashTypedData(dataHash), owner);
        unchecked {
            for (uint256 i = 0; i < numPermitted; ++i) {
                TokenPermissions memory permitted = permit.permitted[i];
                uint256 requestedAmount = transferDetails[i].requestedAmount;
                if (requestedAmount > permitted.amount) revert InvalidAmount(permitted.amount);
                if (requestedAmount != 0) {
                    // allow spender to specify which of the permitted tokens should be transferred
                    ERC20(permitted.token).safeTransferFrom(owner, transferDetails[i].to, requestedAmount);
                }
            }
        }
    }
    /// @inheritdoc ISignatureTransfer
    function invalidateUnorderedNonces(uint256 wordPos, uint256 mask) external {
        nonceBitmap[msg.sender][wordPos] |= mask;
        emit UnorderedNonceInvalidation(msg.sender, wordPos, mask);
    }
    /// @notice Returns the index of the bitmap and the bit position within the bitmap. Used for unordered nonces
    /// @param nonce The nonce to get the associated word and bit positions
    /// @return wordPos The word position or index into the nonceBitmap
    /// @return bitPos The bit position
    /// @dev The first 248 bits of the nonce value is the index of the desired bitmap
    /// @dev The last 8 bits of the nonce value is the position of the bit in the bitmap
    function bitmapPositions(uint256 nonce) private pure returns (uint256 wordPos, uint256 bitPos) {
        wordPos = uint248(nonce >> 8);
        bitPos = uint8(nonce);
    }
    /// @notice Checks whether a nonce is taken and sets the bit at the bit position in the bitmap at the word position
    /// @param from The address to use the nonce at
    /// @param nonce The nonce to spend
    function _useUnorderedNonce(address from, uint256 nonce) internal {
        (uint256 wordPos, uint256 bitPos) = bitmapPositions(nonce);
        uint256 bit = 1 << bitPos;
        uint256 flipped = nonceBitmap[from][wordPos] ^= bit;
        if (flipped & bit == 0) revert InvalidNonce();
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
/// @title AllowanceTransfer
/// @notice Handles ERC20 token permissions through signature based allowance setting and ERC20 token transfers by checking allowed amounts
/// @dev Requires user's token approval on the Permit2 contract
interface IAllowanceTransfer {
    /// @notice Thrown when an allowance on a token has expired.
    /// @param deadline The timestamp at which the allowed amount is no longer valid
    error AllowanceExpired(uint256 deadline);
    /// @notice Thrown when an allowance on a token has been depleted.
    /// @param amount The maximum amount allowed
    error InsufficientAllowance(uint256 amount);
    /// @notice Thrown when too many nonces are invalidated.
    error ExcessiveInvalidation();
    /// @notice Emits an event when the owner successfully invalidates an ordered nonce.
    event NonceInvalidation(
        address indexed owner, address indexed token, address indexed spender, uint48 newNonce, uint48 oldNonce
    );
    /// @notice Emits an event when the owner successfully sets permissions on a token for the spender.
    event Approval(
        address indexed owner, address indexed token, address indexed spender, uint160 amount, uint48 expiration
    );
    /// @notice Emits an event when the owner successfully sets permissions using a permit signature on a token for the spender.
    event Permit(
        address indexed owner,
        address indexed token,
        address indexed spender,
        uint160 amount,
        uint48 expiration,
        uint48 nonce
    );
    /// @notice Emits an event when the owner sets the allowance back to 0 with the lockdown function.
    event Lockdown(address indexed owner, address token, address spender);
    /// @notice The permit data for a token
    struct PermitDetails {
        // ERC20 token address
        address token;
        // the maximum amount allowed to spend
        uint160 amount;
        // timestamp at which a spender's token allowances become invalid
        uint48 expiration;
        // an incrementing value indexed per owner,token,and spender for each signature
        uint48 nonce;
    }
    /// @notice The permit message signed for a single token allownce
    struct PermitSingle {
        // the permit data for a single token alownce
        PermitDetails details;
        // address permissioned on the allowed tokens
        address spender;
        // deadline on the permit signature
        uint256 sigDeadline;
    }
    /// @notice The permit message signed for multiple token allowances
    struct PermitBatch {
        // the permit data for multiple token allowances
        PermitDetails[] details;
        // address permissioned on the allowed tokens
        address spender;
        // deadline on the permit signature
        uint256 sigDeadline;
    }
    /// @notice The saved permissions
    /// @dev This info is saved per owner, per token, per spender and all signed over in the permit message
    /// @dev Setting amount to type(uint160).max sets an unlimited approval
    struct PackedAllowance {
        // amount allowed
        uint160 amount;
        // permission expiry
        uint48 expiration;
        // an incrementing value indexed per owner,token,and spender for each signature
        uint48 nonce;
    }
    /// @notice A token spender pair.
    struct TokenSpenderPair {
        // the token the spender is approved
        address token;
        // the spender address
        address spender;
    }
    /// @notice Details for a token transfer.
    struct AllowanceTransferDetails {
        // the owner of the token
        address from;
        // the recipient of the token
        address to;
        // the amount of the token
        uint160 amount;
        // the token to be transferred
        address token;
    }
    /// @notice A mapping from owner address to token address to spender address to PackedAllowance struct, which contains details and conditions of the approval.
    /// @notice The mapping is indexed in the above order see: allowance[ownerAddress][tokenAddress][spenderAddress]
    /// @dev The packed slot holds the allowed amount, expiration at which the allowed amount is no longer valid, and current nonce thats updated on any signature based approvals.
    function allowance(address, address, address) external view returns (uint160, uint48, uint48);
    /// @notice Approves the spender to use up to amount of the specified token up until the expiration
    /// @param token The token to approve
    /// @param spender The spender address to approve
    /// @param amount The approved amount of the token
    /// @param expiration The timestamp at which the approval is no longer valid
    /// @dev The packed allowance also holds a nonce, which will stay unchanged in approve
    /// @dev Setting amount to type(uint160).max sets an unlimited approval
    function approve(address token, address spender, uint160 amount, uint48 expiration) external;
    /// @notice Permit a spender to a given amount of the owners token via the owner's EIP-712 signature
    /// @dev May fail if the owner's nonce was invalidated in-flight by invalidateNonce
    /// @param owner The owner of the tokens being approved
    /// @param permitSingle Data signed over by the owner specifying the terms of approval
    /// @param signature The owner's signature over the permit data
    function permit(address owner, PermitSingle memory permitSingle, bytes calldata signature) external;
    /// @notice Permit a spender to the signed amounts of the owners tokens via the owner's EIP-712 signature
    /// @dev May fail if the owner's nonce was invalidated in-flight by invalidateNonce
    /// @param owner The owner of the tokens being approved
    /// @param permitBatch Data signed over by the owner specifying the terms of approval
    /// @param signature The owner's signature over the permit data
    function permit(address owner, PermitBatch memory permitBatch, bytes calldata signature) external;
    /// @notice Transfer approved tokens from one address to another
    /// @param from The address to transfer from
    /// @param to The address of the recipient
    /// @param amount The amount of the token to transfer
    /// @param token The token address to transfer
    /// @dev Requires the from address to have approved at least the desired amount
    /// of tokens to msg.sender.
    function transferFrom(address from, address to, uint160 amount, address token) external;
    /// @notice Transfer approved tokens in a batch
    /// @param transferDetails Array of owners, recipients, amounts, and tokens for the transfers
    /// @dev Requires the from addresses to have approved at least the desired amount
    /// of tokens to msg.sender.
    function transferFrom(AllowanceTransferDetails[] calldata transferDetails) external;
    /// @notice Enables performing a "lockdown" of the sender's Permit2 identity
    /// by batch revoking approvals
    /// @param approvals Array of approvals to revoke.
    function lockdown(TokenSpenderPair[] calldata approvals) external;
    /// @notice Invalidate nonces for a given (token, spender) pair
    /// @param token The token to invalidate nonces for
    /// @param spender The spender to invalidate nonces for
    /// @param newNonce The new nonce to set. Invalidates all nonces less than it.
    /// @dev Can't invalidate more than 2**16 nonces per transaction.
    function invalidateNonces(address token, address spender, uint48 newNonce) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
interface IERC1271 {
    /// @dev Should return whether the signature provided is valid for the provided data
    /// @param hash      Hash of the data to be signed
    /// @param signature Signature byte array associated with _data
    /// @return magicValue The bytes4 magic value 0x1626ba7e
    function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
/// @title SignatureTransfer
/// @notice Handles ERC20 token transfers through signature based actions
/// @dev Requires user's token approval on the Permit2 contract
interface ISignatureTransfer {
    /// @notice Thrown when the requested amount for a transfer is larger than the permissioned amount
    /// @param maxAmount The maximum amount a spender can request to transfer
    error InvalidAmount(uint256 maxAmount);
    /// @notice Thrown when the number of tokens permissioned to a spender does not match the number of tokens being transferred
    /// @dev If the spender does not need to transfer the number of tokens permitted, the spender can request amount 0 to be transferred
    error LengthMismatch();
    /// @notice Emits an event when the owner successfully invalidates an unordered nonce.
    event UnorderedNonceInvalidation(address indexed owner, uint256 word, uint256 mask);
    /// @notice The token and amount details for a transfer signed in the permit transfer signature
    struct TokenPermissions {
        // ERC20 token address
        address token;
        // the maximum amount that can be spent
        uint256 amount;
    }
    /// @notice The signed permit message for a single token transfer
    struct PermitTransferFrom {
        TokenPermissions permitted;
        // a unique value for every token owner's signature to prevent signature replays
        uint256 nonce;
        // deadline on the permit signature
        uint256 deadline;
    }
    /// @notice Specifies the recipient address and amount for batched transfers.
    /// @dev Recipients and amounts correspond to the index of the signed token permissions array.
    /// @dev Reverts if the requested amount is greater than the permitted signed amount.
    struct SignatureTransferDetails {
        // recipient address
        address to;
        // spender requested amount
        uint256 requestedAmount;
    }
    /// @notice Used to reconstruct the signed permit message for multiple token transfers
    /// @dev Do not need to pass in spender address as it is required that it is msg.sender
    /// @dev Note that a user still signs over a spender address
    struct PermitBatchTransferFrom {
        // the tokens and corresponding amounts permitted for a transfer
        TokenPermissions[] permitted;
        // a unique value for every token owner's signature to prevent signature replays
        uint256 nonce;
        // deadline on the permit signature
        uint256 deadline;
    }
    /// @notice A map from token owner address and a caller specified word index to a bitmap. Used to set bits in the bitmap to prevent against signature replay protection
    /// @dev Uses unordered nonces so that permit messages do not need to be spent in a certain order
    /// @dev The mapping is indexed first by the token owner, then by an index specified in the nonce
    /// @dev It returns a uint256 bitmap
    /// @dev The index, or wordPosition is capped at type(uint248).max
    function nonceBitmap(address, uint256) external view returns (uint256);
    /// @notice Transfers a token using a signed permit message
    /// @dev Reverts if the requested amount is greater than the permitted signed amount
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails The spender's requested transfer details for the permitted token
    /// @param signature The signature to verify
    function permitTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external;
    /// @notice Transfers a token using a signed permit message
    /// @notice Includes extra data provided by the caller to verify signature over
    /// @dev The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition
    /// @dev Reverts if the requested amount is greater than the permitted signed amount
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails The spender's requested transfer details for the permitted token
    /// @param witness Extra data to include when checking the user signature
    /// @param witnessTypeString The EIP-712 type definition for remaining string stub of the typehash
    /// @param signature The signature to verify
    function permitWitnessTransferFrom(
        PermitTransferFrom memory permit,
        SignatureTransferDetails calldata transferDetails,
        address owner,
        bytes32 witness,
        string calldata witnessTypeString,
        bytes calldata signature
    ) external;
    /// @notice Transfers multiple tokens using a signed permit message
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
    /// @param signature The signature to verify
    function permitTransferFrom(
        PermitBatchTransferFrom memory permit,
        SignatureTransferDetails[] calldata transferDetails,
        address owner,
        bytes calldata signature
    ) external;
    /// @notice Transfers multiple tokens using a signed permit message
    /// @dev The witness type string must follow EIP712 ordering of nested structs and must include the TokenPermissions type definition
    /// @notice Includes extra data provided by the caller to verify signature over
    /// @param permit The permit data signed over by the owner
    /// @param owner The owner of the tokens to transfer
    /// @param transferDetails Specifies the recipient and requested amount for the token transfer
    /// @param witness Extra data to include when checking the user signature
    /// @param witnessTypeString The EIP-712 type definition for remaining string stub of the typehash
    /// @param signature The signature to verify
    function permitWitnessTransferFrom(
        PermitBatchTransferFrom memory permit,
        SignatureTransferDetails[] calldata transferDetails,
        address owner,
        bytes32 witness,
        string calldata witnessTypeString,
        bytes calldata signature
    ) external;
    /// @notice Invalidates the bits specified in mask for the bitmap at the word position
    /// @dev The wordPos is maxed at type(uint248).max
    /// @param wordPos A number to index the nonceBitmap at
    /// @param mask A bitmap masked against msg.sender's current bitmap at the word position
    function invalidateUnorderedNonces(uint256 wordPos, uint256 mask) external;
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
import {IAllowanceTransfer} from "../interfaces/IAllowanceTransfer.sol";
library Allowance {
    // note if the expiration passed is 0, then it the approval set to the block.timestamp
    uint256 private constant BLOCK_TIMESTAMP_EXPIRATION = 0;
    /// @notice Sets the allowed amount, expiry, and nonce of the spender's permissions on owner's token.
    /// @dev Nonce is incremented.
    /// @dev If the inputted expiration is 0, the stored expiration is set to block.timestamp
    function updateAll(
        IAllowanceTransfer.PackedAllowance storage allowed,
        uint160 amount,
        uint48 expiration,
        uint48 nonce
    ) internal {
        uint48 storedNonce;
        unchecked {
            storedNonce = nonce + 1;
        }
        uint48 storedExpiration = expiration == BLOCK_TIMESTAMP_EXPIRATION ? uint48(block.timestamp) : expiration;
        uint256 word = pack(amount, storedExpiration, storedNonce);
        assembly {
            sstore(allowed.slot, word)
        }
    }
    /// @notice Sets the allowed amount and expiry of the spender's permissions on owner's token.
    /// @dev Nonce does not need to be incremented.
    function updateAmountAndExpiration(
        IAllowanceTransfer.PackedAllowance storage allowed,
        uint160 amount,
        uint48 expiration
    ) internal {
        // If the inputted expiration is 0, the allowance only lasts the duration of the block.
        allowed.expiration = expiration == 0 ? uint48(block.timestamp) : expiration;
        allowed.amount = amount;
    }
    /// @notice Computes the packed slot of the amount, expiration, and nonce that make up PackedAllowance
    function pack(uint160 amount, uint48 expiration, uint48 nonce) internal pure returns (uint256 word) {
        word = (uint256(nonce) << 208) | uint256(expiration) << 160 | amount;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
import {IAllowanceTransfer} from "../interfaces/IAllowanceTransfer.sol";
import {ISignatureTransfer} from "../interfaces/ISignatureTransfer.sol";
library PermitHash {
    bytes32 public constant _PERMIT_DETAILS_TYPEHASH =
        keccak256("PermitDetails(address token,uint160 amount,uint48 expiration,uint48 nonce)");
    bytes32 public constant _PERMIT_SINGLE_TYPEHASH = keccak256(
        "PermitSingle(PermitDetails details,address spender,uint256 sigDeadline)PermitDetails(address token,uint160 amount,uint48 expiration,uint48 nonce)"
    );
    bytes32 public constant _PERMIT_BATCH_TYPEHASH = keccak256(
        "PermitBatch(PermitDetails[] details,address spender,uint256 sigDeadline)PermitDetails(address token,uint160 amount,uint48 expiration,uint48 nonce)"
    );
    bytes32 public constant _TOKEN_PERMISSIONS_TYPEHASH = keccak256("TokenPermissions(address token,uint256 amount)");
    bytes32 public constant _PERMIT_TRANSFER_FROM_TYPEHASH = keccak256(
        "PermitTransferFrom(TokenPermissions permitted,address spender,uint256 nonce,uint256 deadline)TokenPermissions(address token,uint256 amount)"
    );
    bytes32 public constant _PERMIT_BATCH_TRANSFER_FROM_TYPEHASH = keccak256(
        "PermitBatchTransferFrom(TokenPermissions[] permitted,address spender,uint256 nonce,uint256 deadline)TokenPermissions(address token,uint256 amount)"
    );
    string public constant _TOKEN_PERMISSIONS_TYPESTRING = "TokenPermissions(address token,uint256 amount)";
    string public constant _PERMIT_TRANSFER_FROM_WITNESS_TYPEHASH_STUB =
        "PermitWitnessTransferFrom(TokenPermissions permitted,address spender,uint256 nonce,uint256 deadline,";
    string public constant _PERMIT_BATCH_WITNESS_TRANSFER_FROM_TYPEHASH_STUB =
        "PermitBatchWitnessTransferFrom(TokenPermissions[] permitted,address spender,uint256 nonce,uint256 deadline,";
    function hash(IAllowanceTransfer.PermitSingle memory permitSingle) internal pure returns (bytes32) {
        bytes32 permitHash = _hashPermitDetails(permitSingle.details);
        return
            keccak256(abi.encode(_PERMIT_SINGLE_TYPEHASH, permitHash, permitSingle.spender, permitSingle.sigDeadline));
    }
    function hash(IAllowanceTransfer.PermitBatch memory permitBatch) internal pure returns (bytes32) {
        uint256 numPermits = permitBatch.details.length;
        bytes32[] memory permitHashes = new bytes32[](numPermits);
        for (uint256 i = 0; i < numPermits; ++i) {
            permitHashes[i] = _hashPermitDetails(permitBatch.details[i]);
        }
        return keccak256(
            abi.encode(
                _PERMIT_BATCH_TYPEHASH,
                keccak256(abi.encodePacked(permitHashes)),
                permitBatch.spender,
                permitBatch.sigDeadline
            )
        );
    }
    function hash(ISignatureTransfer.PermitTransferFrom memory permit) internal view returns (bytes32) {
        bytes32 tokenPermissionsHash = _hashTokenPermissions(permit.permitted);
        return keccak256(
            abi.encode(_PERMIT_TRANSFER_FROM_TYPEHASH, tokenPermissionsHash, msg.sender, permit.nonce, permit.deadline)
        );
    }
    function hash(ISignatureTransfer.PermitBatchTransferFrom memory permit) internal view returns (bytes32) {
        uint256 numPermitted = permit.permitted.length;
        bytes32[] memory tokenPermissionHashes = new bytes32[](numPermitted);
        for (uint256 i = 0; i < numPermitted; ++i) {
            tokenPermissionHashes[i] = _hashTokenPermissions(permit.permitted[i]);
        }
        return keccak256(
            abi.encode(
                _PERMIT_BATCH_TRANSFER_FROM_TYPEHASH,
                keccak256(abi.encodePacked(tokenPermissionHashes)),
                msg.sender,
                permit.nonce,
                permit.deadline
            )
        );
    }
    function hashWithWitness(
        ISignatureTransfer.PermitTransferFrom memory permit,
        bytes32 witness,
        string calldata witnessTypeString
    ) internal view returns (bytes32) {
        bytes32 typeHash = keccak256(abi.encodePacked(_PERMIT_TRANSFER_FROM_WITNESS_TYPEHASH_STUB, witnessTypeString));
        bytes32 tokenPermissionsHash = _hashTokenPermissions(permit.permitted);
        return keccak256(abi.encode(typeHash, tokenPermissionsHash, msg.sender, permit.nonce, permit.deadline, witness));
    }
    function hashWithWitness(
        ISignatureTransfer.PermitBatchTransferFrom memory permit,
        bytes32 witness,
        string calldata witnessTypeString
    ) internal view returns (bytes32) {
        bytes32 typeHash =
            keccak256(abi.encodePacked(_PERMIT_BATCH_WITNESS_TRANSFER_FROM_TYPEHASH_STUB, witnessTypeString));
        uint256 numPermitted = permit.permitted.length;
        bytes32[] memory tokenPermissionHashes = new bytes32[](numPermitted);
        for (uint256 i = 0; i < numPermitted; ++i) {
            tokenPermissionHashes[i] = _hashTokenPermissions(permit.permitted[i]);
        }
        return keccak256(
            abi.encode(
                typeHash,
                keccak256(abi.encodePacked(tokenPermissionHashes)),
                msg.sender,
                permit.nonce,
                permit.deadline,
                witness
            )
        );
    }
    function _hashPermitDetails(IAllowanceTransfer.PermitDetails memory details) private pure returns (bytes32) {
        return keccak256(abi.encode(_PERMIT_DETAILS_TYPEHASH, details));
    }
    function _hashTokenPermissions(ISignatureTransfer.TokenPermissions memory permitted)
        private
        pure
        returns (bytes32)
    {
        return keccak256(abi.encode(_TOKEN_PERMISSIONS_TYPEHASH, permitted));
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.17;
import {IERC1271} from "../interfaces/IERC1271.sol";
library SignatureVerification {
    /// @notice Thrown when the passed in signature is not a valid length
    error InvalidSignatureLength();
    /// @notice Thrown when the recovered signer is equal to the zero address
    error InvalidSignature();
    /// @notice Thrown when the recovered signer does not equal the claimedSigner
    error InvalidSigner();
    /// @notice Thrown when the recovered contract signature is incorrect
    error InvalidContractSignature();
    bytes32 constant UPPER_BIT_MASK = (0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
    function verify(bytes calldata signature, bytes32 hash, address claimedSigner) internal view {
        bytes32 r;
        bytes32 s;
        uint8 v;
        if (claimedSigner.code.length == 0) {
            if (signature.length == 65) {
                (r, s) = abi.decode(signature, (bytes32, bytes32));
                v = uint8(signature[64]);
            } else if (signature.length == 64) {
                // EIP-2098
                bytes32 vs;
                (r, vs) = abi.decode(signature, (bytes32, bytes32));
                s = vs & UPPER_BIT_MASK;
                v = uint8(uint256(vs >> 255)) + 27;
            } else {
                revert InvalidSignatureLength();
            }
            address signer = ecrecover(hash, v, r, s);
            if (signer == address(0)) revert InvalidSignature();
            if (signer != claimedSigner) revert InvalidSigner();
        } else {
            bytes4 magicValue = IERC1271(claimedSigner).isValidSignature(hash, signature);
            if (magicValue != IERC1271.isValidSignature.selector) revert InvalidContractSignature();
        }
    }
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

  The GNU General Public License is a free, copyleft license for
software and other kinds of works.

  The licenses for most software and other practical works are designed
to take away your freedom to share and change the works.  By contrast,
the GNU General Public License is intended to guarantee your freedom to
share and change all versions of a program--to make sure it remains free
software for all its users.  We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors.  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
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  To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights.  Therefore, you have
certain responsibilities if you distribute copies of the software, or if
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  For example, if you distribute copies of such a program, whether
gratis or for a fee, you must pass on to the recipients the same
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know their rights.

  Developers that use the GNU GPL protect your rights with two steps:
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  For the developers' and authors' protection, the GPL clearly explains
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  Some devices are designed to deny users access to install or run
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States should not allow patents to restrict development and use of
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  The precise terms and conditions for copying, distribution and
modification follow.

                       TERMS AND CONDITIONS

  0. Definitions.

  "This License" refers to version 3 of the GNU General Public License.

  "Copyright" also means copyright-like laws that apply to other kinds of
works, such as semiconductor masks.

  "The Program" refers to any copyrightable work licensed under this
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  A "covered work" means either the unmodified Program or a work based
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produce the work, or an object code interpreter used to run it.

  The "Corresponding Source" for a work in object code form means all
the source code needed to generate, install, and (for an executable
work) run the object code and to modify the work, including scripts to
control those activities.  However, it does not include the work's
System Libraries, or general-purpose tools or generally available free
programs which are used unmodified in performing those activities but
which are not part of the work.  For example, Corresponding Source
includes interface definition files associated with source files for
the work, and the source code for shared libraries and dynamically
linked subprograms that the work is specifically designed to require,
such as by intimate data communication or control flow between those
subprograms and other parts of the work.

  The Corresponding Source need not include anything that users
can regenerate automatically from other parts of the Corresponding
Source.

  The Corresponding Source for a work in source code form is that
same work.

  2. Basic Permissions.

  All rights granted under this License are granted for the term of
copyright on the Program, and are irrevocable provided the stated
conditions are met.  This License explicitly affirms your unlimited
permission to run the unmodified Program.  The output from running a
covered work is covered by this License only if the output, given its
content, constitutes a covered work.  This License acknowledges your
rights of fair use or other equivalent, as provided by copyright law.

  You may make, run and propagate covered works that you do not
convey, without conditions so long as your license otherwise remains
in force.  You may convey covered works to others for the sole purpose
of having them make modifications exclusively for you, or provide you
with facilities for running those works, provided that you comply with
the terms of this License in conveying all material for which you do
not control copyright.  Those thus making or running the covered works
for you must do so exclusively on your behalf, under your direction
and control, on terms that prohibit them from making any copies of
your copyrighted material outside their relationship with you.

  Conveying under any other circumstances is permitted solely under
the conditions stated below.  Sublicensing is not allowed; section 10
makes it unnecessary.

  3. Protecting Users' Legal Rights From Anti-Circumvention Law.

  No covered work shall be deemed part of an effective technological
measure under any applicable law fulfilling obligations under article
11 of the WIPO copyright treaty adopted on 20 December 1996, or
similar laws prohibiting or restricting circumvention of such
measures.

  When you convey a covered work, you waive any legal power to forbid
circumvention of technological measures to the extent such circumvention
is effected by exercising rights under this License with respect to
the covered work, and you disclaim any intention to limit operation or
modification of the work as a means of enforcing, against the work's
users, your or third parties' legal rights to forbid circumvention of
technological measures.

  4. Conveying Verbatim Copies.

  You may convey verbatim copies of the Program's source code as you
receive it, in any medium, provided that you conspicuously and
appropriately publish on each copy an appropriate copyright notice;
keep intact all notices stating that this License and any
non-permissive terms added in accord with section 7 apply to the code;
keep intact all notices of the absence of any warranty; and give all
recipients a copy of this License along with the Program.

  You may charge any price or no price for each copy that you convey,
and you may offer support or warranty protection for a fee.

  5. Conveying Modified Source Versions.

  You may convey a work based on the Program, or the modifications to
produce it from the Program, in the form of source code under the
terms of section 4, provided that you also meet all of these conditions:

    a) The work must carry prominent notices stating that you modified
    it, and giving a relevant date.

    b) The work must carry prominent notices stating that it is
    released under this License and any conditions added under section
    7.  This requirement modifies the requirement in section 4 to
    "keep intact all notices".

    c) You must license the entire work, as a whole, under this
    License to anyone who comes into possession of a copy.  This
    License will therefore apply, along with any applicable section 7
    additional terms, to the whole of the work, and all its parts,
    regardless of how they are packaged.  This License gives no
    permission to license the work in any other way, but it does not
    invalidate such permission if you have separately received it.

    d) If the work has interactive user interfaces, each must display
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    interfaces that do not display Appropriate Legal Notices, your
    work need not make them do so.

  A compilation of a covered work with other separate and independent
works, which are not by their nature extensions of the covered work,
and which are not combined with it such as to form a larger program,
in or on a volume of a storage or distribution medium, is called an
"aggregate" if the compilation and its resulting copyright are not
used to limit the access or legal rights of the compilation's users
beyond what the individual works permit.  Inclusion of a covered work
in an aggregate does not cause this License to apply to the other
parts of the aggregate.

  6. Conveying Non-Source Forms.

  You may convey a covered work in object code form under the terms
of sections 4 and 5, provided that you also convey the
machine-readable Corresponding Source under the terms of this License,
in one of these ways:

    a) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by the
    Corresponding Source fixed on a durable physical medium
    customarily used for software interchange.

    b) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by a
    written offer, valid for at least three years and valid for as
    long as you offer spare parts or customer support for that product
    model, to give anyone who possesses the object code either (1) a
    copy of the Corresponding Source for all the software in the
    product that is covered by this License, on a durable physical
    medium customarily used for software interchange, for a price no
    more than your reasonable cost of physically performing this
    conveying of source, or (2) access to copy the
    Corresponding Source from a network server at no charge.

    c) Convey individual copies of the object code with a copy of the
    written offer to provide the Corresponding Source.  This
    alternative is allowed only occasionally and noncommercially, and
    only if you received the object code with such an offer, in accord
    with subsection 6b.

    d) Convey the object code by offering access from a designated
    place (gratis or for a charge), and offer equivalent access to the
    Corresponding Source in the same way through the same place at no
    further charge.  You need not require recipients to copy the
    Corresponding Source along with the object code.  If the place to
    copy the object code is a network server, the Corresponding Source
    may be on a different server (operated by you or a third party)
    that supports equivalent copying facilities, provided you maintain
    clear directions next to the object code saying where to find the
    Corresponding Source.  Regardless of what server hosts the
    Corresponding Source, you remain obligated to ensure that it is
    available for as long as needed to satisfy these requirements.

    e) Convey the object code using peer-to-peer transmission, provided
    you inform other peers where the object code and Corresponding
    Source of the work are being offered to the general public at no
    charge under subsection 6d.

  A separable portion of the object code, whose source code is excluded
from the Corresponding Source as a System Library, need not be
included in conveying the object code work.

  A "User Product" is either (1) a "consumer product", which means any
tangible personal property which is normally used for personal, family,
or household purposes, or (2) anything designed or sold for incorporation
into a dwelling.  In determining whether a product is a consumer product,
doubtful cases shall be resolved in favor of coverage.  For a particular
product received by a particular user, "normally used" refers to a
typical or common use of that class of product, regardless of the status
of the particular user or of the way in which the particular user
actually uses, or expects or is expected to use, the product.  A product
is a consumer product regardless of whether the product has substantial
commercial, industrial or non-consumer uses, unless such uses represent
the only significant mode of use of the product.

  "Installation Information" for a User Product means any methods,
procedures, authorization keys, or other information required to install
and execute modified versions of a covered work in that User Product from
a modified version of its Corresponding Source.  The information must
suffice to ensure that the continued functioning of the modified object
code is in no case prevented or interfered with solely because
modification has been made.

  If you convey an object code work under this section in, or with, or
specifically for use in, a User Product, and the conveying occurs as
part of a transaction in which the right of possession and use of the
User Product is transferred to the recipient in perpetuity or for a
fixed term (regardless of how the transaction is characterized), the
Corresponding Source conveyed under this section must be accompanied
by the Installation Information.  But this requirement does not apply
if neither you nor any third party retains the ability to install
modified object code on the User Product (for example, the work has
been installed in ROM).

  The requirement to provide Installation Information does not include a
requirement to continue to provide support service, warranty, or updates
for a work that has been modified or installed by the recipient, or for
the User Product in which it has been modified or installed.  Access to a
network may be denied when the modification itself materially and
adversely affects the operation of the network or violates the rules and
protocols for communication across the network.

  Corresponding Source conveyed, and Installation Information provided,
in accord with this section must be in a format that is publicly
documented (and with an implementation available to the public in
source code form), and must require no special password or key for
unpacking, reading or copying.

  7. Additional Terms.

  "Additional permissions" are terms that supplement the terms of this
License by making exceptions from one or more of its conditions.
Additional permissions that are applicable to the entire Program shall
be treated as though they were included in this License, to the extent
that they are valid under applicable law.  If additional permissions
apply only to part of the Program, that part may be used separately
under those permissions, but the entire Program remains governed by
this License without regard to the additional permissions.

  When you convey a copy of a covered work, you may at your option
remove any additional permissions from that copy, or from any part of
it.  (Additional permissions may be written to require their own
removal in certain cases when you modify the work.)  You may place
additional permissions on material, added by you to a covered work,
for which you have or can give appropriate copyright permission.

  Notwithstanding any other provision of this License, for material you
add to a covered work, you may (if authorized by the copyright holders of
that material) supplement the terms of this License with terms:

    a) Disclaiming warranty or limiting liability differently from the
    terms of sections 15 and 16 of this License; or

    b) Requiring preservation of specified reasonable legal notices or
    author attributions in that material or in the Appropriate Legal
    Notices displayed by works containing it; or

    c) Prohibiting misrepresentation of the origin of that material, or
    requiring that modified versions of such material be marked in
    reasonable ways as different from the original version; or

    d) Limiting the use for publicity purposes of names of licensors or
    authors of the material; or

    e) Declining to grant rights under trademark law for use of some
    trade names, trademarks, or service marks; or

    f) Requiring indemnification of licensors and authors of that
    material by anyone who conveys the material (or modified versions of
    it) with contractual assumptions of liability to the recipient, for
    any liability that these contractual assumptions directly impose on
    those licensors and authors.

  All other non-permissive additional terms are considered "further
restrictions" within the meaning of section 10.  If the Program as you
received it, or any part of it, contains a notice stating that it is
governed by this License along with a term that is a further
restriction, you may remove that term.  If a license document contains
a further restriction but permits relicensing or conveying under this
License, you may add to a covered work material governed by the terms
of that license document, provided that the further restriction does
not survive such relicensing or conveying.

  If you add terms to a covered work in accord with this section, you
must place, in the relevant source files, a statement of the
additional terms that apply to those files, or a notice indicating
where to find the applicable terms.

  Additional terms, permissive or non-permissive, may be stated in the
form of a separately written license, or stated as exceptions;
the above requirements apply either way.

  8. Termination.

  You may not propagate or modify a covered work except as expressly
provided under this License.  Any attempt otherwise to propagate or
modify it is void, and will automatically terminate your rights under
this License (including any patent licenses granted under the third
paragraph of section 11).

  However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the copyright
holder fails to notify you of the violation by some reasonable means
prior to 60 days after the cessation.

  Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.

  Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, you do not qualify to receive new licenses for the same
material under section 10.

  9. Acceptance Not Required for Having Copies.

  You are not required to accept this License in order to receive or
run a copy of the Program.  Ancillary propagation of a covered work
occurring solely as a consequence of using peer-to-peer transmission
to receive a copy likewise does not require acceptance.  However,
nothing other than this License grants you permission to propagate or
modify any covered work.  These actions infringe copyright if you do
not accept this License.  Therefore, by modifying or propagating a
covered work, you indicate your acceptance of this License to do so.

  10. Automatic Licensing of Downstream Recipients.

  Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License.  You are not responsible
for enforcing compliance by third parties with this License.

  An "entity transaction" is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations.  If propagation of a covered
work results from an entity transaction, each party to that
transaction who receives a copy of the work also receives whatever
licenses to the work the party's predecessor in interest had or could
give under the previous paragraph, plus a right to possession of the
Corresponding Source of the work from the predecessor in interest, if
the predecessor has it or can get it with reasonable efforts.

  You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License.  For example, you may
not impose a license fee, royalty, or other charge for exercise of
rights granted under this License, and you may not initiate litigation
(including a cross-claim or counterclaim in a lawsuit) alleging that
any patent claim is infringed by making, using, selling, offering for
sale, or importing the Program or any portion of it.

  11. Patents.

  A "contributor" is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based.  The
work thus licensed is called the contributor's "contributor version".

  A contributor's "essential patent claims" are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner, permitted
by this License, of making, using, or selling its contributor version,
but do not include claims that would be infringed only as a
consequence of further modification of the contributor version.  For
purposes of this definition, "control" includes the right to grant
patent sublicenses in a manner consistent with the requirements of
this License.

  Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.

  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  You may not convey a covered
work if you are a party to an arrangement with a third party that is
in the business of distributing software, under which you make payment
to the third party based on the extent of your activity of conveying
the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory
patent license (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License.  If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.

  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time.  Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.

  Each version is given a distinguishing version number.  If the
Program specifies that a certain numbered version of the GNU General
Public License "or any later version" applies to it, you have the
option of following the terms and conditions either of that numbered
version or of any later version published by the Free Software
Foundation.  If the Program does not specify a version number of the
GNU General Public License, you may choose any version ever published
by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.

  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.

  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/