// SPDX-License-Identifier: MIXED
// Sources flattened with hardhat v2.14.1 https://hardhat.org
// File contracts/Strings.sol
// License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
pragma solidity ^0.8.0;
/**
* @dev String operations.
*/
library Strings {
bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
/**
* @dev Converts a `uint256` to its ASCII `string` decimal representation.
*/
function toString(uint256 value) internal pure returns (string memory) {
// Inspired by OraclizeAPI's implementation - MIT licence
// https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
if (value == 0) {
return "0";
}
uint256 temp = value;
uint256 digits;
while (temp != 0) {
digits++;
temp /= 10;
}
bytes memory buffer = new bytes(digits);
while (value != 0) {
digits -= 1;
buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
value /= 10;
}
return string(buffer);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
*/
function toHexString(uint256 value) internal pure returns (string memory) {
if (value == 0) {
return "0x00";
}
uint256 temp = value;
uint256 length = 0;
while (temp != 0) {
length++;
temp >>= 8;
}
return toHexString(value, length);
}
/**
* @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
*/
function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
bytes memory buffer = new bytes(2 * length + 2);
buffer[0] = "0";
buffer[1] = "x";
for (uint256 i = 2 * length + 1; i > 1; --i) {
buffer[i] = _HEX_SYMBOLS[value & 0xf];
value >>= 4;
}
require(value == 0, "Strings: hex length insufficient");
return string(buffer);
}
}
// File contracts/ECDSA.sol
// License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/cryptography/ECDSA.sol)
pragma solidity ^0.8.0;
/**
* @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
*
* These functions can be used to verify that a message was signed by the holder
* of the private keys of a given address.
*/
library ECDSA {
enum RecoverError {
NoError,
InvalidSignature,
InvalidSignatureLength,
InvalidSignatureS,
InvalidSignatureV
}
function _throwError(RecoverError error) private pure {
if (error == RecoverError.NoError) {
return; // no error: do nothing
} else if (error == RecoverError.InvalidSignature) {
revert("ECDSA: invalid signature");
} else if (error == RecoverError.InvalidSignatureLength) {
revert("ECDSA: invalid signature length");
} else if (error == RecoverError.InvalidSignatureS) {
revert("ECDSA: invalid signature 's' value");
} else if (error == RecoverError.InvalidSignatureV) {
revert("ECDSA: invalid signature 'v' value");
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature` or error string. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*
* Documentation for signature generation:
* - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
* - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
*
* _Available since v4.3._
*/
function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
// Check the signature length
// - case 65: r,s,v signature (standard)
// - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
if (signature.length == 65) {
bytes32 r;
bytes32 s;
uint8 v;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
s := mload(add(signature, 0x40))
v := byte(0, mload(add(signature, 0x60)))
}
return tryRecover(hash, v, r, s);
} else if (signature.length == 64) {
bytes32 r;
bytes32 vs;
// ecrecover takes the signature parameters, and the only way to get them
// currently is to use assembly.
assembly {
r := mload(add(signature, 0x20))
vs := mload(add(signature, 0x40))
}
return tryRecover(hash, r, vs);
} else {
return (address(0), RecoverError.InvalidSignatureLength);
}
}
/**
* @dev Returns the address that signed a hashed message (`hash`) with
* `signature`. This address can then be used for verification purposes.
*
* The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
* this function rejects them by requiring the `s` value to be in the lower
* half order, and the `v` value to be either 27 or 28.
*
* IMPORTANT: `hash` _must_ be the result of a hash operation for the
* verification to be secure: it is possible to craft signatures that
* recover to arbitrary addresses for non-hashed data. A safe way to ensure
* this is by receiving a hash of the original message (which may otherwise
* be too long), and then calling {toEthSignedMessageHash} on it.
*/
function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, signature);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
*
* See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address, RecoverError) {
bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
uint8 v = uint8((uint256(vs) >> 255) + 27);
return tryRecover(hash, v, r, s);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
*
* _Available since v4.2._
*/
function recover(
bytes32 hash,
bytes32 r,
bytes32 vs
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, r, vs);
_throwError(error);
return recovered;
}
/**
* @dev Overload of {ECDSA-tryRecover} that receives the `v`,
* `r` and `s` signature fields separately.
*
* _Available since v4.3._
*/
function tryRecover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address, RecoverError) {
// EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
// unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
// the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
// signatures from current libraries generate a unique signature with an s-value in the lower half order.
//
// If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
// with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
// vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
// these malleable signatures as well.
if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
return (address(0), RecoverError.InvalidSignatureS);
}
if (v != 27 && v != 28) {
return (address(0), RecoverError.InvalidSignatureV);
}
// If the signature is valid (and not malleable), return the signer address
address signer = ecrecover(hash, v, r, s);
if (signer == address(0)) {
return (address(0), RecoverError.InvalidSignature);
}
return (signer, RecoverError.NoError);
}
/**
* @dev Overload of {ECDSA-recover} that receives the `v`,
* `r` and `s` signature fields separately.
*/
function recover(
bytes32 hash,
uint8 v,
bytes32 r,
bytes32 s
) internal pure returns (address) {
(address recovered, RecoverError error) = tryRecover(hash, v, r, s);
_throwError(error);
return recovered;
}
/**
* @dev Returns an Ethereum Signed Message, created from a `hash`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
// 32 is the length in bytes of hash,
// enforced by the type signature above
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
}
/**
* @dev Returns an Ethereum Signed Message, created from `s`. This
* produces hash corresponding to the one signed with the
* https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
* JSON-RPC method as part of EIP-191.
*
* See {recover}.
*/
function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(s.length), s));
}
/**
* @dev Returns an Ethereum Signed Typed Data, created from a
* `domainSeparator` and a `structHash`. This produces hash corresponding
* to the one signed with the
* https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
* JSON-RPC method as part of EIP-712.
*
* See {recover}.
*/
function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
}
}
// File contracts/IDP2PStateMachine.sol
// License-Identifier: UNLICENSED
pragma solidity ^0.8.0;
interface IDP2PStateMachine {
enum DealState {
ZERO, // 0
START, // 1
PAYMENT_COMPLETE, // 2 legacy
DISPUTE, // 3 legacy
CANCELED_ARBITER, // 4
CANCELED_TIMEOUT_ARBITER, // 5
CANCELED_BUYER, // 6
CANCELED_SELLER, // 7 impossible state
CLEARED_SELLER, // 8
CLEARED_ARBITER // 9
}
struct DealData {
address token;
address seller;
address buyer;
address arbiter;
address feeReceiver;
uint256 amount;
uint256 fee;
uint256 nonce;
bytes32 extra;
}
event StateChanged(bytes32 indexed dealHash, DealData deal, DealState state, address creator);
function startDeal(DealData calldata deal) external payable returns (bytes32);
function cancelDealBuyer(DealData calldata deal) external;
function clearDealSeller(DealData calldata deal) external;
function cancelTimeoutArbiter(DealData calldata deal) external;
function cancelDealArbiter(DealData calldata deal) external;
function clearDealArbiter(DealData calldata deal) external;
function claim(address token, address receiver) external;
}
// File contracts/DP2PStateMachine.sol
// License-Identifier: UNLICENCED
pragma solidity ^0.8.0;
abstract contract DP2PStateMachine is IDP2PStateMachine {
mapping(bytes32 => DealState) public deals;
mapping(address => mapping(address => uint256)) public fees; // token -> addr -> fees
modifier isValidStateTransfer(DealData calldata deal, DealState toState) {
bytes32 _hash = dealHash(deal);
require(deals[_hash] == DealState.START, 'Wrong deal state or deal is missing');
deals[_hash] = toState;
_;
emit StateChanged(_hash, deal, toState, msg.sender);
}
modifier onlyArbiter(DealData calldata deal) {
require(deal.arbiter == msg.sender, 'arbiter != msgSender()');
_;
}
modifier onlyBuyer(DealData calldata deal) {
require(deal.buyer == msg.sender, 'buyer != msgSender()');
_;
}
modifier onlySeller(DealData calldata deal) {
require(deal.seller == msg.sender, 'seller != msgSender()');
_;
}
function startDeal(
DealData calldata deal
) external payable virtual override onlySeller(deal) returns (bytes32) {
bytes32 _hash = dealHash(deal);
require(deals[_hash] == DealState.ZERO, 'storage slot collision');
deals[_hash] = DealState.START;
_transferFrom(deal.token, deal.seller, address(this), deal.amount + deal.fee);
emit StateChanged(_hash, deal, DealState.START, msg.sender);
return _hash;
}
function cancelDealBuyer(
DealData calldata deal
) external override onlyBuyer(deal) isValidStateTransfer(deal, DealState.CANCELED_BUYER) {
_cancelDeal(deal);
}
function clearDealSeller(
DealData calldata deal
) external override onlySeller(deal) isValidStateTransfer(deal, DealState.CLEARED_SELLER) {
_clearDeal(deal);
}
function cancelTimeoutArbiter(
DealData calldata deal
)
external
override
onlyArbiter(deal)
isValidStateTransfer(deal, DealState.CANCELED_TIMEOUT_ARBITER)
{
_cancelDeal(deal);
}
function cancelDealArbiter(
DealData calldata deal
) external override onlyArbiter(deal) isValidStateTransfer(deal, DealState.CANCELED_ARBITER) {
_cancelDeal(deal);
}
function clearDealArbiter(
DealData calldata deal
) external override onlyArbiter(deal) isValidStateTransfer(deal, DealState.CLEARED_ARBITER) {
_clearDeal(deal);
}
function claim(address token, address receiver) external override {
uint256 amount = fees[token][msg.sender];
require(amount > 0, 'has no accumulated fees');
fees[token][msg.sender] = 0;
_transfer(token, receiver, amount);
}
function dealHash(DealData calldata deal) internal pure returns (bytes32) {
return keccak256(abi.encode(deal));
}
function _cancelDeal(DealData calldata deal) internal {
_transfer(deal.token, deal.seller, deal.amount + deal.fee);
}
function _clearDeal(DealData calldata deal) internal {
fees[deal.token][deal.feeReceiver] += deal.fee;
_transfer(deal.token, deal.buyer, deal.amount);
}
function _transfer(address token, address _to, uint256 _value) internal virtual;
function _transferFrom(
address token,
address _from,
address _to,
uint256 _value
) internal virtual;
}
// File contracts/Address.sol
// 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);
}
}
}
}
// File contracts/IERC20.sol
// 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);
}
// File contracts/SafeERC20.sol
// License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
/**
* @title SafeERC20
* @dev Wrappers around ERC20 operations that throw on failure (when the token
* contract returns false). Tokens that return no value (and instead revert or
* throw on failure) are also supported, non-reverting calls are assumed to be
* successful.
* To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
* which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
*/
library SafeERC20 {
using Address for address;
function safeTransfer(
IERC20 token,
address to,
uint256 value
) internal {
_callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
}
function safeTransferFrom(
IERC20 token,
address from,
address to,
uint256 value
) internal {
_callOptionalReturn(
token,
abi.encodeWithSelector(token.transferFrom.selector, from, to, value)
);
}
/**
* @dev Deprecated. This function has issues similar to the ones found in
* {IERC20-approve}, and its usage is discouraged.
*
* Whenever possible, use {safeIncreaseAllowance} and
* {safeDecreaseAllowance} instead.
*/
function safeApprove(
IERC20 token,
address spender,
uint256 value
) internal {
// safeApprove should only be called when setting an initial allowance,
// or when resetting it to zero. To increase and decrease it, use
// 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
require(
(value == 0) || (token.allowance(address(this), spender) == 0),
'SafeERC20: approve from non-zero to non-zero allowance'
);
_callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
}
function safeIncreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
uint256 newAllowance = token.allowance(address(this), spender) + value;
_callOptionalReturn(
token,
abi.encodeWithSelector(token.approve.selector, spender, newAllowance)
);
}
function safeDecreaseAllowance(
IERC20 token,
address spender,
uint256 value
) internal {
unchecked {
uint256 oldAllowance = token.allowance(address(this), spender);
require(oldAllowance >= value, 'SafeERC20: decreased allowance below zero');
uint256 newAllowance = oldAllowance - value;
_callOptionalReturn(
token,
abi.encodeWithSelector(token.approve.selector, spender, newAllowance)
);
}
}
/**
* @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
* on the return value: the return value is optional (but if data is returned, it must not be false).
* @param token The token targeted by the call.
* @param data The call data (encoded using abi.encode or one of its variants).
*/
function _callOptionalReturn(IERC20 token, bytes memory data) private {
// We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
// we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
// the target address contains contract code and also asserts for success in the low-level call.
bytes memory returndata = address(token).functionCall(
data,
'SafeERC20: low-level call failed'
);
if (returndata.length > 0) {
// Return data is optional
require(abi.decode(returndata, (bool)), 'SafeERC20: ERC20 operation did not succeed');
}
}
}
// File contracts/DP2PToken.sol
// License-Identifier: UNLICENCED
pragma solidity ^0.8.0;
contract DP2PToken is DP2PStateMachine {
using Address for address;
string public constant VERSION = '4.0-token-dp2p';
function _transfer(address token, address _to, uint256 _value) internal override {
SafeERC20.safeTransfer(IERC20(token), _to, _value);
}
function _transferFrom(
address token,
address _from,
address _to,
uint256 _value
) internal override {
SafeERC20.safeTransferFrom(IERC20(token), _from, _to, _value);
}
}
{
"compilationTarget": {
"DP2PToken.sol": "DP2PToken"
},
"evmVersion": "paris",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": true,
"runs": 200
},
"remappings": []
}
[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"bytes32","name":"dealHash","type":"bytes32"},{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"indexed":false,"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"},{"indexed":false,"internalType":"enum IDP2PStateMachine.DealState","name":"state","type":"uint8"},{"indexed":false,"internalType":"address","name":"creator","type":"address"}],"name":"StateChanged","type":"event"},{"inputs":[],"name":"VERSION","outputs":[{"internalType":"string","name":"","type":"string"}],"stateMutability":"view","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"}],"name":"cancelDealArbiter","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"}],"name":"cancelDealBuyer","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"}],"name":"cancelTimeoutArbiter","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"receiver","type":"address"}],"name":"claim","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"}],"name":"clearDealArbiter","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"}],"name":"clearDealSeller","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"name":"deals","outputs":[{"internalType":"enum IDP2PStateMachine.DealState","name":"","type":"uint8"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"address","name":"","type":"address"}],"name":"fees","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"components":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"seller","type":"address"},{"internalType":"address","name":"buyer","type":"address"},{"internalType":"address","name":"arbiter","type":"address"},{"internalType":"address","name":"feeReceiver","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256","name":"fee","type":"uint256"},{"internalType":"uint256","name":"nonce","type":"uint256"},{"internalType":"bytes32","name":"extra","type":"bytes32"}],"internalType":"struct IDP2PStateMachine.DealData","name":"deal","type":"tuple"}],"name":"startDeal","outputs":[{"internalType":"bytes32","name":"","type":"bytes32"}],"stateMutability":"payable","type":"function"}]