Contract Source Code:
//SPDX-License-Identifier: MIT
pragma solidity 0.8.9;
import "@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/AddressUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
import "@openzeppelin/contracts-upgradeable/utils/ContextUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/security/PausableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
interface Aggregator {
function latestRoundData()
external
view
returns (
uint80 roundId,
int256 answer,
uint256 startedAt,
uint256 updatedAt,
uint80 answeredInRound
);
}
contract PresaleV2 is
Initializable,
ReentrancyGuardUpgradeable,
OwnableUpgradeable,
PausableUpgradeable
{
uint256 public totalTokensSold;
uint256 public startTime;
uint256 public endTime;
uint256 public claimStart;
address public saleToken;
uint256 public baseDecimals;
uint256 public maxTokensToBuy;
uint256 public currentStep;
uint256 public NINE_MONTHS;
struct UserInfo {
uint256 boughtAmount;
uint256 initialClaim;
uint256 claimedAmount;
}
IERC20Upgradeable public USDTInterface;
Aggregator public aggregatorInterface;
// https://docs.chain.link/docs/ethereum-addresses/ => (ETH / USD)
uint256[3] public token_amount;
uint256[3] public token_price;
mapping(address => UserInfo) public userInfo;
event SaleTimeSet(uint256 _start, uint256 _end, uint256 timestamp);
event SaleTimeUpdated(
bytes32 indexed key,
uint256 prevValue,
uint256 newValue,
uint256 timestamp
);
event TokensBought(
address indexed user,
uint256 indexed tokensBought,
address indexed purchaseToken,
uint256 amountPaid,
uint256 timestamp
);
event TokensAdded(
address indexed token,
uint256 noOfTokens,
uint256 timestamp
);
event TokensClaimed(
address indexed user,
uint256 amount,
uint256 timestamp
);
event ClaimStartUpdated(
uint256 prevValue,
uint256 newValue,
uint256 timestamp
);
/// @custom:oz-upgrades-unsafe-allow constructor
constructor() initializer {}
/**
* @dev Initializes the contract and sets key parameters
* @param _oracle Oracle contract to fetch ETH/USDT price
* @param _usdt USDT token contract address
* @param _startTime start time of the presale
* @param _endTime end time of the presale
*/
function initialize(
address _oracle,
address _usdt,
uint256 _startTime,
uint256 _endTime
) external initializer {
require(_oracle != address(0), "Zero aggregator address");
require(_usdt != address(0), "Zero USDT address");
require(
_startTime > block.timestamp && _endTime > _startTime,
"Invalid time"
);
__Pausable_init_unchained();
__Ownable_init_unchained();
__ReentrancyGuard_init_unchained();
maxTokensToBuy = 85_000_000;
baseDecimals = (10**18);
token_amount = [90_000_000, 180_000_000, 270_000_000];
token_price = [
20000000000000000, // 0.02 USD
25000000000000000, // 0.025 USD
32000000000000000 // 0.032 USD
];
NINE_MONTHS = (270 * 86400); // 9 months in seconds
aggregatorInterface = Aggregator(_oracle);
USDTInterface = IERC20Upgradeable(_usdt);
startTime = _startTime;
endTime = _endTime;
emit SaleTimeSet(startTime, endTime, block.timestamp);
}
/**
* @dev To pause the presale
*/
function pause() external onlyOwner {
_pause();
}
/**
* @dev To unpause the presale
*/
function unpause() external onlyOwner {
_unpause();
}
/**
* @dev To calculate the price in USD for given amount of tokens.
* @param _amount No of tokens
*/
function calculatePrice(uint256 _amount)
internal
view
returns (uint256 totalValue)
{
uint256 USDTAmount;
require(_amount <= maxTokensToBuy, "Amount exceeds max tokens to buy");
if (_amount + totalTokensSold > token_amount[currentStep]) {
require(currentStep < 2, "Insufficient token amount.");
uint256 tokenAmountForCurrentPrice = token_amount[currentStep] -
totalTokensSold;
USDTAmount =
tokenAmountForCurrentPrice *
token_price[currentStep] +
(_amount - tokenAmountForCurrentPrice) *
token_price[currentStep + 1];
} else USDTAmount = _amount * token_price[currentStep];
return USDTAmount;
}
/**
* @dev To update the sale times
* @param _startTime New start time
* @param _endTime New end time
*/
function changeSaleTimes(uint256 _startTime, uint256 _endTime)
external
onlyOwner
{
require(_startTime > 0 || _endTime > 0, "Invalid parameters");
if (_startTime > 0) {
require(block.timestamp < startTime, "Sale already started");
require(block.timestamp < _startTime, "Sale time in past");
uint256 prevValue = startTime;
startTime = _startTime;
emit SaleTimeUpdated(
bytes32("START"),
prevValue,
_startTime,
block.timestamp
);
}
if (_endTime > 0) {
require(_endTime > startTime, "Invalid endTime");
uint256 prevValue = endTime;
endTime = _endTime;
emit SaleTimeUpdated(
bytes32("END"),
prevValue,
_endTime,
block.timestamp
);
}
}
/**
* @dev To get latest ethereum price in 10**18 format
*/
function getLatestPrice() public view returns (uint256) {
(, int256 price, , , ) = aggregatorInterface.latestRoundData();
price = (price * (10**10));
return uint256(price);
}
modifier checkSaleState(uint256 amount) {
require(
block.timestamp >= startTime && block.timestamp <= endTime,
"Invalid time for buying"
);
require(amount > 0, "Invalid sale amount");
_;
}
/**
* @dev To buy into a presale using USDT
* @param amount No of tokens to buy
*/
function buyWithUSDT(uint256 amount)
external
checkSaleState(amount)
whenNotPaused
returns (bool)
{
uint256 usdPrice = usdtBuyHelper(amount);
totalTokensSold += amount;
if (totalTokensSold > token_amount[currentStep]) currentStep += 1;
UserInfo storage userDetails = userInfo[_msgSender()];
userDetails.boughtAmount += (amount * baseDecimals);
userDetails.initialClaim = (userDetails.boughtAmount * 10) / 100;
uint256 ourAllowance = USDTInterface.allowance(
_msgSender(),
address(this)
);
require(usdPrice <= ourAllowance, "Make sure to add enough allowance");
(bool success, ) = address(USDTInterface).call(
abi.encodeWithSignature(
"transferFrom(address,address,uint256)",
_msgSender(),
owner(),
usdPrice
)
);
require(success, "Token payment failed");
emit TokensBought(
_msgSender(),
amount,
address(USDTInterface),
usdPrice,
block.timestamp
);
return true;
}
/**
* @dev To buy into a presale using ETH
* @param amount No of tokens to buy
*/
function buyWithEth(uint256 amount)
external
payable
checkSaleState(amount)
whenNotPaused
nonReentrant
returns (bool)
{
uint256 ethAmount = ethBuyHelper(amount);
require(msg.value >= ethAmount, "Less payment");
uint256 excess = msg.value - ethAmount;
totalTokensSold += amount;
if (totalTokensSold > token_amount[currentStep]) currentStep += 1;
UserInfo storage userDetails = userInfo[_msgSender()];
userDetails.boughtAmount += (amount * baseDecimals);
userDetails.initialClaim = (userDetails.boughtAmount * 10) / 100;
sendValue(payable(owner()), ethAmount);
if (excess > 0) sendValue(payable(_msgSender()), excess);
emit TokensBought(
_msgSender(),
amount,
address(0),
ethAmount,
block.timestamp
);
return true;
}
/**
* @dev Helper funtion to get ETH price for given amount
* @param amount No of tokens to buy
*/
function ethBuyHelper(uint256 amount)
public
view
returns (uint256 ethAmount)
{
uint256 usdPrice = calculatePrice(amount);
ethAmount = (usdPrice * baseDecimals) / getLatestPrice();
}
/**
* @dev Helper funtion to get USDT price for given amount
* @param amount No of tokens to buy
*/
function usdtBuyHelper(uint256 amount)
public
view
returns (uint256 usdPrice)
{
usdPrice = calculatePrice(amount);
usdPrice = usdPrice / (10**12);
}
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Low balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "ETH Payment failed");
}
/**
* @dev To set the claim start time and sale token address by the owner
* @param _claimStart claim start time
* @param noOfTokens no of tokens to add to the contract
* @param _saleToken sale toke address
*/
function startClaim(
uint256 _claimStart,
uint256 noOfTokens,
address _saleToken
) external onlyOwner returns (bool) {
require(
_claimStart > endTime && _claimStart > block.timestamp,
"Invalid claim start time"
);
require(
noOfTokens >= (totalTokensSold * baseDecimals),
"Tokens less than sold"
);
require(_saleToken != address(0), "Zero token address");
require(claimStart == 0, "Claim already set");
claimStart = _claimStart;
saleToken = _saleToken;
bool success = IERC20Upgradeable(_saleToken).transferFrom(
_msgSender(),
address(this),
noOfTokens
);
require(success, "Token transfer failed");
emit TokensAdded(saleToken, noOfTokens, block.timestamp);
return true;
}
/**
* @dev To change the claim start time by the owner
* @param _claimStart new claim start time
*/
function changeClaimStart(uint256 _claimStart)
external
onlyOwner
returns (bool)
{
require(claimStart > 0, "Initial claim data not set");
require(_claimStart > endTime, "Sale in progress");
require(_claimStart > block.timestamp, "Claim start in past");
uint256 prevValue = claimStart;
claimStart = _claimStart;
emit ClaimStartUpdated(prevValue, _claimStart, block.timestamp);
return true;
}
/**
* @dev To claim tokens after claiming starts
*/
function claim() external whenNotPaused returns (bool) {
require(saleToken != address(0), "Sale token not added");
uint256 tokens = getClaimableAmount(_msgSender());
require(tokens > 0, "No claimable tokens available");
userInfo[_msgSender()].claimedAmount += tokens;
bool success = IERC20Upgradeable(saleToken).transfer(
_msgSender(),
tokens
);
require(success, "Token transfer failed");
emit TokensClaimed(_msgSender(), tokens, block.timestamp);
return true;
}
/**
* @dev Helper funtion to get claimable tokens for a user after claiming starts
* @param _user Address of the user
*/
function getClaimableAmount(address _user)
public
view
returns (uint256 claimableAmount)
{
require(claimStart > 0, "Claim start time not set");
UserInfo memory userDetails = userInfo[_user];
require(userDetails.boughtAmount > 0, "No tokens available for user");
if (userDetails.boughtAmount - userDetails.claimedAmount == 0) return 0;
if (block.timestamp < claimStart) return 0;
if (block.timestamp < (claimStart + NINE_MONTHS)) {
uint256 timePassedRatio = ((block.timestamp - claimStart) *
baseDecimals) / (NINE_MONTHS);
claimableAmount =
(((userDetails.boughtAmount - userDetails.initialClaim) *
timePassedRatio) / baseDecimals) +
userDetails.initialClaim;
} else {
claimableAmount = userDetails.boughtAmount;
}
claimableAmount = claimableAmount - userDetails.claimedAmount;
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract ContextUpgradeable is Initializable {
function __Context_init() internal onlyInitializing {
}
function __Context_init_unchained() internal onlyInitializing {
}
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
/**
* @dev This empty reserved space is put in place to allow future versions to add new
* variables without shifting down storage in the inheritance chain.
* See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
*/
uint256[50] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20Upgradeable {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 amount) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 amount) external returns (bool);
/**
* @dev Moves `amount` tokens from `from` to `to` using the
* allowance mechanism. `amount` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(
address from,
address to,
uint256 amount
) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library AddressUpgradeable {
/**
* @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 Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
/// @solidity memory-safe-assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* By default, the owner account will be the one that deploys the contract. This
* can later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the deployer as the initial owner.
*/
function __Ownable_init() internal onlyInitializing {
__Ownable_init_unchained();
}
function __Ownable_init_unchained() internal onlyInitializing {
_transferOwnership(_msgSender());
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
require(owner() == _msgSender(), "Ownable: caller is not the owner");
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions anymore. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby removing any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
require(newOwner != address(0), "Ownable: new owner is the zero address");
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
/**
* @dev This empty reserved space is put in place to allow future versions to add new
* variables without shifting down storage in the inheritance chain.
* See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
*/
uint256[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
pragma solidity ^0.8.2;
import "../../utils/AddressUpgradeable.sol";
/**
* @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
* behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
* external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
* function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
*
* The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
* reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
* case an upgrade adds a module that needs to be initialized.
*
* For example:
*
* [.hljs-theme-light.nopadding]
* ```
* contract MyToken is ERC20Upgradeable {
* function initialize() initializer public {
* __ERC20_init("MyToken", "MTK");
* }
* }
* contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
* function initializeV2() reinitializer(2) public {
* __ERC20Permit_init("MyToken");
* }
* }
* ```
*
* TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
* possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
*
* CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
* that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
*
* [CAUTION]
* ====
* Avoid leaving a contract uninitialized.
*
* An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
* contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
* the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
*
* [.hljs-theme-light.nopadding]
* ```
* /// @custom:oz-upgrades-unsafe-allow constructor
* constructor() {
* _disableInitializers();
* }
* ```
* ====
*/
abstract contract Initializable {
/**
* @dev Indicates that the contract has been initialized.
* @custom:oz-retyped-from bool
*/
uint8 private _initialized;
/**
* @dev Indicates that the contract is in the process of being initialized.
*/
bool private _initializing;
/**
* @dev Triggered when the contract has been initialized or reinitialized.
*/
event Initialized(uint8 version);
/**
* @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
* `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
*/
modifier initializer() {
bool isTopLevelCall = !_initializing;
require(
(isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
"Initializable: contract is already initialized"
);
_initialized = 1;
if (isTopLevelCall) {
_initializing = true;
}
_;
if (isTopLevelCall) {
_initializing = false;
emit Initialized(1);
}
}
/**
* @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
* contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
* used to initialize parent contracts.
*
* `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
* initialization step. This is essential to configure modules that are added through upgrades and that require
* initialization.
*
* Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
* a contract, executing them in the right order is up to the developer or operator.
*/
modifier reinitializer(uint8 version) {
require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
_initialized = version;
_initializing = true;
_;
_initializing = false;
emit Initialized(version);
}
/**
* @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
* {initializer} and {reinitializer} modifiers, directly or indirectly.
*/
modifier onlyInitializing() {
require(_initializing, "Initializable: contract is not initializing");
_;
}
/**
* @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
* Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
* to any version. It is recommended to use this to lock implementation contracts that are designed to be called
* through proxies.
*/
function _disableInitializers() internal virtual {
require(!_initializing, "Initializable: contract is initializing");
if (_initialized < type(uint8).max) {
_initialized = type(uint8).max;
emit Initialized(type(uint8).max);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
pragma solidity ^0.8.0;
import "../utils/ContextUpgradeable.sol";
import "../proxy/utils/Initializable.sol";
/**
* @dev Contract module which allows children to implement an emergency stop
* mechanism that can be triggered by an authorized account.
*
* This module is used through inheritance. It will make available the
* modifiers `whenNotPaused` and `whenPaused`, which can be applied to
* the functions of your contract. Note that they will not be pausable by
* simply including this module, only once the modifiers are put in place.
*/
abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
/**
* @dev Emitted when the pause is triggered by `account`.
*/
event Paused(address account);
/**
* @dev Emitted when the pause is lifted by `account`.
*/
event Unpaused(address account);
bool private _paused;
/**
* @dev Initializes the contract in unpaused state.
*/
function __Pausable_init() internal onlyInitializing {
__Pausable_init_unchained();
}
function __Pausable_init_unchained() internal onlyInitializing {
_paused = false;
}
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*
* Requirements:
*
* - The contract must not be paused.
*/
modifier whenNotPaused() {
_requireNotPaused();
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*
* Requirements:
*
* - The contract must be paused.
*/
modifier whenPaused() {
_requirePaused();
_;
}
/**
* @dev Returns true if the contract is paused, and false otherwise.
*/
function paused() public view virtual returns (bool) {
return _paused;
}
/**
* @dev Throws if the contract is paused.
*/
function _requireNotPaused() internal view virtual {
require(!paused(), "Pausable: paused");
}
/**
* @dev Throws if the contract is not paused.
*/
function _requirePaused() internal view virtual {
require(paused(), "Pausable: not paused");
}
/**
* @dev Triggers stopped state.
*
* Requirements:
*
* - The contract must not be paused.
*/
function _pause() internal virtual whenNotPaused {
_paused = true;
emit Paused(_msgSender());
}
/**
* @dev Returns to normal state.
*
* Requirements:
*
* - The contract must be paused.
*/
function _unpause() internal virtual whenPaused {
_paused = false;
emit Unpaused(_msgSender());
}
/**
* @dev This empty reserved space is put in place to allow future versions to add new
* variables without shifting down storage in the inheritance chain.
* See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
*/
uint256[49] private __gap;
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
import "../proxy/utils/Initializable.sol";
/**
* @dev Contract module that helps prevent reentrant calls to a function.
*
* Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
* available, which can be applied to functions to make sure there are no nested
* (reentrant) calls to them.
*
* Note that because there is a single `nonReentrant` guard, functions marked as
* `nonReentrant` may not call one another. This can be worked around by making
* those functions `private`, and then adding `external` `nonReentrant` entry
* points to them.
*
* TIP: If you would like to learn more about reentrancy and alternative ways
* to protect against it, check out our blog post
* https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
*/
abstract contract ReentrancyGuardUpgradeable is Initializable {
// Booleans are more expensive than uint256 or any type that takes up a full
// word because each write operation emits an extra SLOAD to first read the
// slot's contents, replace the bits taken up by the boolean, and then write
// back. This is the compiler's defense against contract upgrades and
// pointer aliasing, and it cannot be disabled.
// The values being non-zero value makes deployment a bit more expensive,
// but in exchange the refund on every call to nonReentrant will be lower in
// amount. Since refunds are capped to a percentage of the total
// transaction's gas, it is best to keep them low in cases like this one, to
// increase the likelihood of the full refund coming into effect.
uint256 private constant _NOT_ENTERED = 1;
uint256 private constant _ENTERED = 2;
uint256 private _status;
function __ReentrancyGuard_init() internal onlyInitializing {
__ReentrancyGuard_init_unchained();
}
function __ReentrancyGuard_init_unchained() internal onlyInitializing {
_status = _NOT_ENTERED;
}
/**
* @dev Prevents a contract from calling itself, directly or indirectly.
* Calling a `nonReentrant` function from another `nonReentrant`
* function is not supported. It is possible to prevent this from happening
* by making the `nonReentrant` function external, and making it call a
* `private` function that does the actual work.
*/
modifier nonReentrant() {
// On the first call to nonReentrant, _notEntered will be true
require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
// Any calls to nonReentrant after this point will fail
_status = _ENTERED;
_;
// By storing the original value once again, a refund is triggered (see
// https://eips.ethereum.org/EIPS/eip-2200)
_status = _NOT_ENTERED;
}
/**
* @dev This empty reserved space is put in place to allow future versions to add new
* variables without shifting down storage in the inheritance chain.
* See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
*/
uint256[49] private __gap;
}