Transaction Hash:
Block:
21301751 at Nov-30-2024 04:41:23 PM +UTC
Transaction Fee:
0.00106048674363978 ETH
$1.91
Gas Used:
64,620 Gas / 16.411122619 Gwei
Emitted Events:
172 |
TetherToken.Approval( owner=[Receiver] FlaryTokenSale, spender=[Receiver] FlaryTokenSale, value=30000 )
|
173 |
TetherToken.Transfer( from=[Receiver] FlaryTokenSale, to=[Sender] 0x5683f934c30c7ae6345926a83ed0be0e714fadde, value=30000 )
|
Account State Difference:
Address | Before | After | State Difference | ||
---|---|---|---|---|---|
0x4838B106...B0BAD5f97
Miner
| (Titan Builder) | 5.488031648506322118 Eth | 5.488105143959219298 Eth | 0.00007349545289718 | |
0x5683F934...E714faDdE |
0.008062250409461216 Eth
Nonce: 15
|
0.007001763665821436 Eth
Nonce: 16
| 0.00106048674363978 | ||
0xdAC17F95...13D831ec7 |
Execution Trace
FlaryTokenSale.withdrawUSDT( _amount=30000 )
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TetherToken.approve( _spender=0x1ea9Bcd9C7483c9570057921459F4A64aFf39b0d, _value=30000 )
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TetherToken.transferFrom( _from=0x1ea9Bcd9C7483c9570057921459F4A64aFf39b0d, _to=0x5683F934c30c7AE6345926A83eD0be0E714faDdE, _value=30000 )
File 1 of 2: FlaryTokenSale
File 2 of 2: TetherToken
// SPDX-License-Identifier: MIT pragma solidity 0.8.22; import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol"; import {Pausable} from "@openzeppelin/contracts/utils/Pausable.sol"; import {ReentrancyGuard} from "@openzeppelin/contracts/utils/ReentrancyGuard.sol"; import {ERC20} from "@openzeppelin/contracts/token/ERC20/ERC20.sol"; import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol"; import {AggregatorV3Interface} from "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol"; contract FlaryTokenSale is Ownable, Pausable, ReentrancyGuard { using SafeERC20 for ERC20; ERC20 public usdt; AggregatorV3Interface public nativeUsdPriceFeed; uint256 public tokensPriceInUsdt; uint256 public tokenSold; mapping(address => uint256) public investemetByAddress; address[] public buyers; constructor( address _usdt, address _priceFeed, uint256 _tokensPriceInUsdt ) Ownable(msg.sender) { usdt = ERC20(_usdt); nativeUsdPriceFeed = AggregatorV3Interface(_priceFeed); tokensPriceInUsdt = _tokensPriceInUsdt; } function buyTokensNative() external payable whenNotPaused { buyers.push(msg.sender); (, int256 nativePrice, , , ) = nativeUsdPriceFeed.latestRoundData(); uint8 feed_Decimals = nativeUsdPriceFeed.decimals(); uint8 usdtDecimals = usdt.decimals(); // assuming token's decimals 18 uint256 tokensAmount; if (feed_Decimals > usdtDecimals) { tokensAmount = (msg.value * uint256(nativePrice)) / (tokensPriceInUsdt * 10 ** (feed_Decimals - usdtDecimals)); } else { tokensAmount = (msg.value * uint256(nativePrice) * 10 ** (usdtDecimals - feed_Decimals)) / tokensPriceInUsdt; } investemetByAddress[msg.sender] += tokensAmount; tokenSold += tokensAmount; } function buyTokensUSDT(uint256 amount) external whenNotPaused { usdt.safeTransferFrom(msg.sender, address(this), amount); uint256 tokensAmount = (amount * 10 ** 18) / tokensPriceInUsdt; investemetByAddress[msg.sender] += tokensAmount; tokenSold += tokensAmount; } function pause() external whenNotPaused onlyOwner { _pause(); } function unpause() external whenPaused onlyOwner { _unpause(); } function withdrawUSDT(uint256 _amount) external onlyOwner { usdt.forceApprove(address(this), _amount); usdt.safeTransferFrom(address(this), owner(), _amount); } function withdrawNative(uint256 _amount) external onlyOwner { (bool hs, ) = payable(owner()).call{value: _amount}(""); require(hs, "EnergiWanBridge:: Failed to withdraw native coins"); } function changePrice(uint256 _tokensPriceInUsdt) external onlyOwner { tokensPriceInUsdt = _tokensPriceInUsdt; } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol) pragma solidity ^0.8.20; import {Context} from "../utils/Context.sol"; /** * @dev Contract module which provides a basic access control mechanism, where * there is an account (an owner) that can be granted exclusive access to * specific functions. * * The initial owner is set to the address provided by the deployer. This can * later be changed with {transferOwnership}. * * This module is used through inheritance. It will make available the modifier * `onlyOwner`, which can be applied to your functions to restrict their use to * the owner. */ abstract contract Ownable is Context { address private _owner; /** * @dev The caller account is not authorized to perform an operation. */ error OwnableUnauthorizedAccount(address account); /** * @dev The owner is not a valid owner account. (eg. `address(0)`) */ error OwnableInvalidOwner(address owner); event OwnershipTransferred(address indexed previousOwner, address indexed newOwner); /** * @dev Initializes the contract setting the address provided by the deployer as the initial owner. */ constructor(address initialOwner) { if (initialOwner == address(0)) { revert OwnableInvalidOwner(address(0)); } _transferOwnership(initialOwner); } /** * @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 { if (owner() != _msgSender()) { revert OwnableUnauthorizedAccount(_msgSender()); } } /** * @dev Leaves the contract without owner. It will not be possible to call * `onlyOwner` functions. Can only be called by the current owner. * * NOTE: Renouncing ownership will leave the contract without an owner, * thereby disabling 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 { if (newOwner == address(0)) { revert OwnableInvalidOwner(address(0)); } _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); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (utils/Pausable.sol) pragma solidity ^0.8.20; import {Context} from "../utils/Context.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 Pausable is Context { bool private _paused; /** * @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); /** * @dev The operation failed because the contract is paused. */ error EnforcedPause(); /** * @dev The operation failed because the contract is not paused. */ error ExpectedPause(); /** * @dev Initializes the contract in unpaused state. */ constructor() { _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 { if (paused()) { revert EnforcedPause(); } } /** * @dev Throws if the contract is not paused. */ function _requirePaused() internal view virtual { if (!paused()) { revert ExpectedPause(); } } /** * @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()); } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (utils/ReentrancyGuard.sol) pragma solidity ^0.8.20; /** * @dev Contract module that helps prevent reentrant calls to a function. * * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier * available, which can be applied to functions to make sure there are no nested * (reentrant) calls to them. * * Note that because there is a single `nonReentrant` guard, functions marked as * `nonReentrant` may not call one another. This can be worked around by making * those functions `private`, and then adding `external` `nonReentrant` entry * points to them. * * TIP: If you would like to learn more about reentrancy and alternative ways * to protect against it, check out our blog post * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul]. */ abstract contract ReentrancyGuard { // Booleans are more expensive than uint256 or any type that takes up a full // word because each write operation emits an extra SLOAD to first read the // slot's contents, replace the bits taken up by the boolean, and then write // back. This is the compiler's defense against contract upgrades and // pointer aliasing, and it cannot be disabled. // The values being non-zero value makes deployment a bit more expensive, // but in exchange the refund on every call to nonReentrant will be lower in // amount. Since refunds are capped to a percentage of the total // transaction's gas, it is best to keep them low in cases like this one, to // increase the likelihood of the full refund coming into effect. uint256 private constant NOT_ENTERED = 1; uint256 private constant ENTERED = 2; uint256 private _status; /** * @dev Unauthorized reentrant call. */ error ReentrancyGuardReentrantCall(); constructor() { _status = NOT_ENTERED; } /** * @dev Prevents a contract from calling itself, directly or indirectly. * Calling a `nonReentrant` function from another `nonReentrant` * function is not supported. It is possible to prevent this from happening * by making the `nonReentrant` function external, and making it call a * `private` function that does the actual work. */ modifier nonReentrant() { _nonReentrantBefore(); _; _nonReentrantAfter(); } function _nonReentrantBefore() private { // On the first call to nonReentrant, _status will be NOT_ENTERED if (_status == ENTERED) { revert ReentrancyGuardReentrantCall(); } // Any calls to nonReentrant after this point will fail _status = ENTERED; } function _nonReentrantAfter() private { // By storing the original value once again, a refund is triggered (see // https://eips.ethereum.org/EIPS/eip-2200) _status = NOT_ENTERED; } /** * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a * `nonReentrant` function in the call stack. */ function _reentrancyGuardEntered() internal view returns (bool) { return _status == ENTERED; } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol) pragma solidity ^0.8.20; import {IERC20} from "./IERC20.sol"; import {IERC20Metadata} from "./extensions/IERC20Metadata.sol"; import {Context} from "../../utils/Context.sol"; import {IERC20Errors} from "../../interfaces/draft-IERC6093.sol"; /** * @dev Implementation of the {IERC20} interface. * * This implementation is agnostic to the way tokens are created. This means * that a supply mechanism has to be added in a derived contract using {_mint}. * * TIP: For a detailed writeup see our guide * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How * to implement supply mechanisms]. * * The default value of {decimals} is 18. To change this, you should override * this function so it returns a different value. * * We have followed general OpenZeppelin Contracts guidelines: functions revert * instead returning `false` on failure. This behavior is nonetheless * conventional and does not conflict with the expectations of ERC20 * applications. * * Additionally, an {Approval} event is emitted on calls to {transferFrom}. * This allows applications to reconstruct the allowance for all accounts just * by listening to said events. Other implementations of the EIP may not emit * these events, as it isn't required by the specification. */ abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors { mapping(address account => uint256) private _balances; mapping(address account => mapping(address spender => uint256)) private _allowances; uint256 private _totalSupply; string private _name; string private _symbol; /** * @dev Sets the values for {name} and {symbol}. * * All two of these values are immutable: they can only be set once during * construction. */ constructor(string memory name_, string memory symbol_) { _name = name_; _symbol = symbol_; } /** * @dev Returns the name of the token. */ function name() public view virtual returns (string memory) { return _name; } /** * @dev Returns the symbol of the token, usually a shorter version of the * name. */ function symbol() public view virtual returns (string memory) { return _symbol; } /** * @dev Returns the number of decimals used to get its user representation. * For example, if `decimals` equals `2`, a balance of `505` tokens should * be displayed to a user as `5.05` (`505 / 10 ** 2`). * * Tokens usually opt for a value of 18, imitating the relationship between * Ether and Wei. This is the default value returned by this function, unless * it's overridden. * * NOTE: This information is only used for _display_ purposes: it in * no way affects any of the arithmetic of the contract, including * {IERC20-balanceOf} and {IERC20-transfer}. */ function decimals() public view virtual returns (uint8) { return 18; } /** * @dev See {IERC20-totalSupply}. */ function totalSupply() public view virtual returns (uint256) { return _totalSupply; } /** * @dev See {IERC20-balanceOf}. */ function balanceOf(address account) public view virtual returns (uint256) { return _balances[account]; } /** * @dev See {IERC20-transfer}. * * Requirements: * * - `to` cannot be the zero address. * - the caller must have a balance of at least `value`. */ function transfer(address to, uint256 value) public virtual returns (bool) { address owner = _msgSender(); _transfer(owner, to, value); return true; } /** * @dev See {IERC20-allowance}. */ function allowance(address owner, address spender) public view virtual returns (uint256) { return _allowances[owner][spender]; } /** * @dev See {IERC20-approve}. * * NOTE: If `value` is the maximum `uint256`, the allowance is not updated on * `transferFrom`. This is semantically equivalent to an infinite approval. * * Requirements: * * - `spender` cannot be the zero address. */ function approve(address spender, uint256 value) public virtual returns (bool) { address owner = _msgSender(); _approve(owner, spender, value); return true; } /** * @dev See {IERC20-transferFrom}. * * Emits an {Approval} event indicating the updated allowance. This is not * required by the EIP. See the note at the beginning of {ERC20}. * * NOTE: Does not update the allowance if the current allowance * is the maximum `uint256`. * * Requirements: * * - `from` and `to` cannot be the zero address. * - `from` must have a balance of at least `value`. * - the caller must have allowance for ``from``'s tokens of at least * `value`. */ function transferFrom(address from, address to, uint256 value) public virtual returns (bool) { address spender = _msgSender(); _spendAllowance(from, spender, value); _transfer(from, to, value); return true; } /** * @dev Moves a `value` amount of tokens from `from` to `to`. * * This internal function is equivalent to {transfer}, and can be used to * e.g. implement automatic token fees, slashing mechanisms, etc. * * Emits a {Transfer} event. * * NOTE: This function is not virtual, {_update} should be overridden instead. */ function _transfer(address from, address to, uint256 value) internal { if (from == address(0)) { revert ERC20InvalidSender(address(0)); } if (to == address(0)) { revert ERC20InvalidReceiver(address(0)); } _update(from, to, value); } /** * @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from` * (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding * this function. * * Emits a {Transfer} event. */ function _update(address from, address to, uint256 value) internal virtual { if (from == address(0)) { // Overflow check required: The rest of the code assumes that totalSupply never overflows _totalSupply += value; } else { uint256 fromBalance = _balances[from]; if (fromBalance < value) { revert ERC20InsufficientBalance(from, fromBalance, value); } unchecked { // Overflow not possible: value <= fromBalance <= totalSupply. _balances[from] = fromBalance - value; } } if (to == address(0)) { unchecked { // Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply. _totalSupply -= value; } } else { unchecked { // Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256. _balances[to] += value; } } emit Transfer(from, to, value); } /** * @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0). * Relies on the `_update` mechanism * * Emits a {Transfer} event with `from` set to the zero address. * * NOTE: This function is not virtual, {_update} should be overridden instead. */ function _mint(address account, uint256 value) internal { if (account == address(0)) { revert ERC20InvalidReceiver(address(0)); } _update(address(0), account, value); } /** * @dev Destroys a `value` amount of tokens from `account`, lowering the total supply. * Relies on the `_update` mechanism. * * Emits a {Transfer} event with `to` set to the zero address. * * NOTE: This function is not virtual, {_update} should be overridden instead */ function _burn(address account, uint256 value) internal { if (account == address(0)) { revert ERC20InvalidSender(address(0)); } _update(account, address(0), value); } /** * @dev Sets `value` as the allowance of `spender` over the `owner` s tokens. * * This internal function is equivalent to `approve`, and can be used to * e.g. set automatic allowances for certain subsystems, etc. * * Emits an {Approval} event. * * Requirements: * * - `owner` cannot be the zero address. * - `spender` cannot be the zero address. * * Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument. */ function _approve(address owner, address spender, uint256 value) internal { _approve(owner, spender, value, true); } /** * @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event. * * By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by * `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any * `Approval` event during `transferFrom` operations. * * Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to * true using the following override: * ``` * function _approve(address owner, address spender, uint256 value, bool) internal virtual override { * super._approve(owner, spender, value, true); * } * ``` * * Requirements are the same as {_approve}. */ function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual { if (owner == address(0)) { revert ERC20InvalidApprover(address(0)); } if (spender == address(0)) { revert ERC20InvalidSpender(address(0)); } _allowances[owner][spender] = value; if (emitEvent) { emit Approval(owner, spender, value); } } /** * @dev Updates `owner` s allowance for `spender` based on spent `value`. * * Does not update the allowance value in case of infinite allowance. * Revert if not enough allowance is available. * * Does not emit an {Approval} event. */ function _spendAllowance(address owner, address spender, uint256 value) internal virtual { uint256 currentAllowance = allowance(owner, spender); if (currentAllowance != type(uint256).max) { if (currentAllowance < value) { revert ERC20InsufficientAllowance(spender, currentAllowance, value); } unchecked { _approve(owner, spender, currentAllowance - value, false); } } } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/utils/SafeERC20.sol) pragma solidity ^0.8.20; import {IERC20} from "../IERC20.sol"; import {IERC20Permit} from "../extensions/IERC20Permit.sol"; import {Address} from "../../../utils/Address.sol"; /** * @title SafeERC20 * @dev Wrappers around ERC20 operations that throw on failure (when the token * contract returns false). Tokens that return no value (and instead revert or * throw on failure) are also supported, non-reverting calls are assumed to be * successful. * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract, * which allows you to call the safe operations as `token.safeTransfer(...)`, etc. */ library SafeERC20 { using Address for address; /** * @dev An operation with an ERC20 token failed. */ error SafeERC20FailedOperation(address token); /** * @dev Indicates a failed `decreaseAllowance` request. */ error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease); /** * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value, * non-reverting calls are assumed to be successful. */ function safeTransfer(IERC20 token, address to, uint256 value) internal { _callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value))); } /** * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful. */ function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal { _callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value))); } /** * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value, * non-reverting calls are assumed to be successful. */ function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal { uint256 oldAllowance = token.allowance(address(this), spender); forceApprove(token, spender, oldAllowance + value); } /** * @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no * value, non-reverting calls are assumed to be successful. */ function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal { unchecked { uint256 currentAllowance = token.allowance(address(this), spender); if (currentAllowance < requestedDecrease) { revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease); } forceApprove(token, spender, currentAllowance - requestedDecrease); } } /** * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value, * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval * to be set to zero before setting it to a non-zero value, such as USDT. */ function forceApprove(IERC20 token, address spender, uint256 value) internal { bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value)); if (!_callOptionalReturnBool(token, approvalCall)) { _callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0))); _callOptionalReturn(token, approvalCall); } } /** * @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); if (returndata.length != 0 && !abi.decode(returndata, (bool))) { revert SafeERC20FailedOperation(address(token)); } } /** * @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). * * This is a variant of {_callOptionalReturn} that silents catches all reverts and returns a bool instead. */ function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) { // 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 cannot use {Address-functionCall} here since this should return false // and not revert is the subcall reverts. (bool success, bytes memory returndata) = address(token).call(data); return success && (returndata.length == 0 || abi.decode(returndata, (bool))) && address(token).code.length > 0; } } // SPDX-License-Identifier: MIT pragma solidity ^0.8.0; interface AggregatorV3Interface { function decimals() external view returns (uint8); function description() external view returns (string memory); function version() external view returns (uint256); function getRoundData( uint80 _roundId ) external view returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound); function latestRoundData() external view returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol) pragma solidity ^0.8.20; /** * @dev Provides information about the current execution context, including the * sender of the transaction and its data. While these are generally available * via msg.sender and msg.data, they should not be accessed in such a direct * manner, since when dealing with meta-transactions the account sending and * paying for execution may not be the actual sender (as far as an application * is concerned). * * This contract is only required for intermediate, library-like contracts. */ abstract contract Context { function _msgSender() internal view virtual returns (address) { return msg.sender; } function _msgData() internal view virtual returns (bytes calldata) { return msg.data; } function _contextSuffixLength() internal view virtual returns (uint256) { return 0; } } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol) pragma solidity ^0.8.20; /** * @dev Interface of the ERC20 standard as defined in the EIP. */ interface IERC20 { /** * @dev Emitted when `value` tokens are moved from one account (`from`) to * another (`to`). * * Note that `value` may be zero. */ event Transfer(address indexed from, address indexed to, uint256 value); /** * @dev Emitted when the allowance of a `spender` for an `owner` is set by * a call to {approve}. `value` is the new allowance. */ event Approval(address indexed owner, address indexed spender, uint256 value); /** * @dev Returns the value of tokens in existence. */ function totalSupply() external view returns (uint256); /** * @dev Returns the value of tokens owned by `account`. */ function balanceOf(address account) external view returns (uint256); /** * @dev Moves a `value` amount of 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 value) 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 a `value` amount of tokens 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 value) external returns (bool); /** * @dev Moves a `value` amount of tokens from `from` to `to` using the * allowance mechanism. `value` 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 value) external returns (bool); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol) pragma solidity ^0.8.20; import {IERC20} from "../IERC20.sol"; /** * @dev Interface for the optional metadata functions from the ERC20 standard. */ interface IERC20Metadata is IERC20 { /** * @dev Returns the name of the token. */ function name() external view returns (string memory); /** * @dev Returns the symbol of the token. */ function symbol() external view returns (string memory); /** * @dev Returns the decimals places of the token. */ function decimals() external view returns (uint8); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (interfaces/draft-IERC6093.sol) pragma solidity ^0.8.20; /** * @dev Standard ERC20 Errors * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC20 tokens. */ interface IERC20Errors { /** * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. * @param balance Current balance for the interacting account. * @param needed Minimum amount required to perform a transfer. */ error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed); /** * @dev Indicates a failure with the token `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. */ error ERC20InvalidSender(address sender); /** * @dev Indicates a failure with the token `receiver`. Used in transfers. * @param receiver Address to which tokens are being transferred. */ error ERC20InvalidReceiver(address receiver); /** * @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers. * @param spender Address that may be allowed to operate on tokens without being their owner. * @param allowance Amount of tokens a `spender` is allowed to operate with. * @param needed Minimum amount required to perform a transfer. */ error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed); /** * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals. * @param approver Address initiating an approval operation. */ error ERC20InvalidApprover(address approver); /** * @dev Indicates a failure with the `spender` to be approved. Used in approvals. * @param spender Address that may be allowed to operate on tokens without being their owner. */ error ERC20InvalidSpender(address spender); } /** * @dev Standard ERC721 Errors * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC721 tokens. */ interface IERC721Errors { /** * @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20. * Used in balance queries. * @param owner Address of the current owner of a token. */ error ERC721InvalidOwner(address owner); /** * @dev Indicates a `tokenId` whose `owner` is the zero address. * @param tokenId Identifier number of a token. */ error ERC721NonexistentToken(uint256 tokenId); /** * @dev Indicates an error related to the ownership over a particular token. Used in transfers. * @param sender Address whose tokens are being transferred. * @param tokenId Identifier number of a token. * @param owner Address of the current owner of a token. */ error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner); /** * @dev Indicates a failure with the token `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. */ error ERC721InvalidSender(address sender); /** * @dev Indicates a failure with the token `receiver`. Used in transfers. * @param receiver Address to which tokens are being transferred. */ error ERC721InvalidReceiver(address receiver); /** * @dev Indicates a failure with the `operator`’s approval. Used in transfers. * @param operator Address that may be allowed to operate on tokens without being their owner. * @param tokenId Identifier number of a token. */ error ERC721InsufficientApproval(address operator, uint256 tokenId); /** * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals. * @param approver Address initiating an approval operation. */ error ERC721InvalidApprover(address approver); /** * @dev Indicates a failure with the `operator` to be approved. Used in approvals. * @param operator Address that may be allowed to operate on tokens without being their owner. */ error ERC721InvalidOperator(address operator); } /** * @dev Standard ERC1155 Errors * Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC1155 tokens. */ interface IERC1155Errors { /** * @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. * @param balance Current balance for the interacting account. * @param needed Minimum amount required to perform a transfer. * @param tokenId Identifier number of a token. */ error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId); /** * @dev Indicates a failure with the token `sender`. Used in transfers. * @param sender Address whose tokens are being transferred. */ error ERC1155InvalidSender(address sender); /** * @dev Indicates a failure with the token `receiver`. Used in transfers. * @param receiver Address to which tokens are being transferred. */ error ERC1155InvalidReceiver(address receiver); /** * @dev Indicates a failure with the `operator`’s approval. Used in transfers. * @param operator Address that may be allowed to operate on tokens without being their owner. * @param owner Address of the current owner of a token. */ error ERC1155MissingApprovalForAll(address operator, address owner); /** * @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals. * @param approver Address initiating an approval operation. */ error ERC1155InvalidApprover(address approver); /** * @dev Indicates a failure with the `operator` to be approved. Used in approvals. * @param operator Address that may be allowed to operate on tokens without being their owner. */ error ERC1155InvalidOperator(address operator); /** * @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation. * Used in batch transfers. * @param idsLength Length of the array of token identifiers * @param valuesLength Length of the array of token amounts */ error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Permit.sol) pragma solidity ^0.8.20; /** * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612]. * * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't * need to send a transaction, and thus is not required to hold Ether at all. * * ==== Security Considerations * * There are two important considerations concerning the use of `permit`. The first is that a valid permit signature * expresses an allowance, and it should not be assumed to convey additional meaning. In particular, it should not be * considered as an intention to spend the allowance in any specific way. The second is that because permits have * built-in replay protection and can be submitted by anyone, they can be frontrun. A protocol that uses permits should * take this into consideration and allow a `permit` call to fail. Combining these two aspects, a pattern that may be * generally recommended is: * * ```solidity * function doThingWithPermit(..., uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) public { * try token.permit(msg.sender, address(this), value, deadline, v, r, s) {} catch {} * doThing(..., value); * } * * function doThing(..., uint256 value) public { * token.safeTransferFrom(msg.sender, address(this), value); * ... * } * ``` * * Observe that: 1) `msg.sender` is used as the owner, leaving no ambiguity as to the signer intent, and 2) the use of * `try/catch` allows the permit to fail and makes the code tolerant to frontrunning. (See also * {SafeERC20-safeTransferFrom}). * * Additionally, note that smart contract wallets (such as Argent or Safe) are not able to produce permit signatures, so * contracts should have entry points that don't rely on permit. */ interface IERC20Permit { /** * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens, * given ``owner``'s signed approval. * * IMPORTANT: The same issues {IERC20-approve} has related to transaction * ordering also apply here. * * Emits an {Approval} event. * * Requirements: * * - `spender` cannot be the zero address. * - `deadline` must be a timestamp in the future. * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner` * over the EIP712-formatted function arguments. * - the signature must use ``owner``'s current nonce (see {nonces}). * * For more information on the signature format, see the * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP * section]. * * CAUTION: See Security Considerations above. */ function permit( address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s ) external; /** * @dev Returns the current nonce for `owner`. This value must be * included whenever a signature is generated for {permit}. * * Every successful call to {permit} increases ``owner``'s nonce by one. This * prevents a signature from being used multiple times. */ function nonces(address owner) external view returns (uint256); /** * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}. */ // solhint-disable-next-line func-name-mixedcase function DOMAIN_SEPARATOR() external view returns (bytes32); } // SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v5.0.0) (utils/Address.sol) pragma solidity ^0.8.20; /** * @dev Collection of functions related to the address type */ library Address { /** * @dev The ETH balance of the account is not enough to perform the operation. */ error AddressInsufficientBalance(address account); /** * @dev There's no code at `target` (it is not a contract). */ error AddressEmptyCode(address target); /** * @dev A call to an address target failed. The target may have reverted. */ error FailedInnerCall(); /** * @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://consensys.net/diligence/blog/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/v0.8.20/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern]. */ function sendValue(address payable recipient, uint256 amount) internal { if (address(this).balance < amount) { revert AddressInsufficientBalance(address(this)); } (bool success, ) = recipient.call{value: amount}(""); if (!success) { revert FailedInnerCall(); } } /** * @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 or custom error, it is bubbled * up by this function (like regular Solidity function calls). However, if * the call reverted with no returned reason, this function reverts with a * {FailedInnerCall} error. * * 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. */ function functionCall(address target, bytes memory data) internal returns (bytes memory) { return functionCallWithValue(target, data, 0); } /** * @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`. */ function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) { if (address(this).balance < value) { revert AddressInsufficientBalance(address(this)); } (bool success, bytes memory returndata) = target.call{value: value}(data); return verifyCallResultFromTarget(target, success, returndata); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a static call. */ function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) { (bool success, bytes memory returndata) = target.staticcall(data); return verifyCallResultFromTarget(target, success, returndata); } /** * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], * but performing a delegate call. */ function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) { (bool success, bytes memory returndata) = target.delegatecall(data); return verifyCallResultFromTarget(target, success, returndata); } /** * @dev Tool to verify that a low level call to smart-contract was successful, and reverts if the target * was not a contract or bubbling up the revert reason (falling back to {FailedInnerCall}) in case of an * unsuccessful call. */ function verifyCallResultFromTarget( address target, bool success, bytes memory returndata ) internal view returns (bytes memory) { if (!success) { _revert(returndata); } else { // only check if target is a contract if the call was successful and the return data is empty // otherwise we already know that it was a contract if (returndata.length == 0 && target.code.length == 0) { revert AddressEmptyCode(target); } return returndata; } } /** * @dev Tool to verify that a low level call was successful, and reverts if it wasn't, either by bubbling the * revert reason or with a default {FailedInnerCall} error. */ function verifyCallResult(bool success, bytes memory returndata) internal pure returns (bytes memory) { if (!success) { _revert(returndata); } else { return returndata; } } /** * @dev Reverts with returndata if present. Otherwise reverts with {FailedInnerCall}. */ function _revert(bytes memory returndata) private pure { // 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 FailedInnerCall(); } } }
File 2 of 2: TetherToken
pragma solidity ^0.4.17; /** * @title SafeMath * @dev Math operations with safety checks that throw on error */ library SafeMath { function mul(uint256 a, uint256 b) internal pure returns (uint256) { if (a == 0) { return 0; } uint256 c = a * b; assert(c / a == b); return c; } function div(uint256 a, uint256 b) internal pure returns (uint256) { // assert(b > 0); // Solidity automatically throws when dividing by 0 uint256 c = a / b; // assert(a == b * c + a % b); // There is no case in which this doesn't hold return c; } function sub(uint256 a, uint256 b) internal pure returns (uint256) { assert(b <= a); return a - b; } function add(uint256 a, uint256 b) internal pure returns (uint256) { uint256 c = a + b; assert(c >= a); return c; } } /** * @title Ownable * @dev The Ownable contract has an owner address, and provides basic authorization control * functions, this simplifies the implementation of "user permissions". */ contract Ownable { address public owner; /** * @dev The Ownable constructor sets the original `owner` of the contract to the sender * account. */ function Ownable() public { owner = msg.sender; } /** * @dev Throws if called by any account other than the owner. */ modifier onlyOwner() { require(msg.sender == owner); _; } /** * @dev Allows the current owner to transfer control of the contract to a newOwner. * @param newOwner The address to transfer ownership to. */ function transferOwnership(address newOwner) public onlyOwner { if (newOwner != address(0)) { owner = newOwner; } } } /** * @title ERC20Basic * @dev Simpler version of ERC20 interface * @dev see https://github.com/ethereum/EIPs/issues/20 */ contract ERC20Basic { uint public _totalSupply; function totalSupply() public constant returns (uint); function balanceOf(address who) public constant returns (uint); function transfer(address to, uint value) public; event Transfer(address indexed from, address indexed to, uint value); } /** * @title ERC20 interface * @dev see https://github.com/ethereum/EIPs/issues/20 */ contract ERC20 is ERC20Basic { function allowance(address owner, address spender) public constant returns (uint); function transferFrom(address from, address to, uint value) public; function approve(address spender, uint value) public; event Approval(address indexed owner, address indexed spender, uint value); } /** * @title Basic token * @dev Basic version of StandardToken, with no allowances. */ contract BasicToken is Ownable, ERC20Basic { using SafeMath for uint; mapping(address => uint) public balances; // additional variables for use if transaction fees ever became necessary uint public basisPointsRate = 0; uint public maximumFee = 0; /** * @dev Fix for the ERC20 short address attack. */ modifier onlyPayloadSize(uint size) { require(!(msg.data.length < size + 4)); _; } /** * @dev transfer token for a specified address * @param _to The address to transfer to. * @param _value The amount to be transferred. */ function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) { uint fee = (_value.mul(basisPointsRate)).div(10000); if (fee > maximumFee) { fee = maximumFee; } uint sendAmount = _value.sub(fee); balances[msg.sender] = balances[msg.sender].sub(_value); balances[_to] = balances[_to].add(sendAmount); if (fee > 0) { balances[owner] = balances[owner].add(fee); Transfer(msg.sender, owner, fee); } Transfer(msg.sender, _to, sendAmount); } /** * @dev Gets the balance of the specified address. * @param _owner The address to query the the balance of. * @return An uint representing the amount owned by the passed address. */ function balanceOf(address _owner) public constant returns (uint balance) { return balances[_owner]; } } /** * @title Standard ERC20 token * * @dev Implementation of the basic standard token. * @dev https://github.com/ethereum/EIPs/issues/20 * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol */ contract StandardToken is BasicToken, ERC20 { mapping (address => mapping (address => uint)) public allowed; uint public constant MAX_UINT = 2**256 - 1; /** * @dev Transfer tokens from one address to another * @param _from address The address which you want to send tokens from * @param _to address The address which you want to transfer to * @param _value uint the amount of tokens to be transferred */ function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) { var _allowance = allowed[_from][msg.sender]; // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met // if (_value > _allowance) throw; uint fee = (_value.mul(basisPointsRate)).div(10000); if (fee > maximumFee) { fee = maximumFee; } if (_allowance < MAX_UINT) { allowed[_from][msg.sender] = _allowance.sub(_value); } uint sendAmount = _value.sub(fee); balances[_from] = balances[_from].sub(_value); balances[_to] = balances[_to].add(sendAmount); if (fee > 0) { balances[owner] = balances[owner].add(fee); Transfer(_from, owner, fee); } Transfer(_from, _to, sendAmount); } /** * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender. * @param _spender The address which will spend the funds. * @param _value The amount of tokens to be spent. */ function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) { // To change the approve amount you first have to reduce the addresses` // allowance to zero by calling `approve(_spender, 0)` if it is not // already 0 to mitigate the race condition described here: // https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729 require(!((_value != 0) && (allowed[msg.sender][_spender] != 0))); allowed[msg.sender][_spender] = _value; Approval(msg.sender, _spender, _value); } /** * @dev Function to check the amount of tokens than an owner allowed to a spender. * @param _owner address The address which owns the funds. * @param _spender address The address which will spend the funds. * @return A uint specifying the amount of tokens still available for the spender. */ function allowance(address _owner, address _spender) public constant returns (uint remaining) { return allowed[_owner][_spender]; } } /** * @title Pausable * @dev Base contract which allows children to implement an emergency stop mechanism. */ contract Pausable is Ownable { event Pause(); event Unpause(); bool public paused = false; /** * @dev Modifier to make a function callable only when the contract is not paused. */ modifier whenNotPaused() { require(!paused); _; } /** * @dev Modifier to make a function callable only when the contract is paused. */ modifier whenPaused() { require(paused); _; } /** * @dev called by the owner to pause, triggers stopped state */ function pause() onlyOwner whenNotPaused public { paused = true; Pause(); } /** * @dev called by the owner to unpause, returns to normal state */ function unpause() onlyOwner whenPaused public { paused = false; Unpause(); } } contract BlackList is Ownable, BasicToken { /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) /////// function getBlackListStatus(address _maker) external constant returns (bool) { return isBlackListed[_maker]; } function getOwner() external constant returns (address) { return owner; } mapping (address => bool) public isBlackListed; function addBlackList (address _evilUser) public onlyOwner { isBlackListed[_evilUser] = true; AddedBlackList(_evilUser); } function removeBlackList (address _clearedUser) public onlyOwner { isBlackListed[_clearedUser] = false; RemovedBlackList(_clearedUser); } function destroyBlackFunds (address _blackListedUser) public onlyOwner { require(isBlackListed[_blackListedUser]); uint dirtyFunds = balanceOf(_blackListedUser); balances[_blackListedUser] = 0; _totalSupply -= dirtyFunds; DestroyedBlackFunds(_blackListedUser, dirtyFunds); } event DestroyedBlackFunds(address _blackListedUser, uint _balance); event AddedBlackList(address _user); event RemovedBlackList(address _user); } contract UpgradedStandardToken is StandardToken{ // those methods are called by the legacy contract // and they must ensure msg.sender to be the contract address function transferByLegacy(address from, address to, uint value) public; function transferFromByLegacy(address sender, address from, address spender, uint value) public; function approveByLegacy(address from, address spender, uint value) public; } contract TetherToken is Pausable, StandardToken, BlackList { string public name; string public symbol; uint public decimals; address public upgradedAddress; bool public deprecated; // The contract can be initialized with a number of tokens // All the tokens are deposited to the owner address // // @param _balance Initial supply of the contract // @param _name Token Name // @param _symbol Token symbol // @param _decimals Token decimals function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public { _totalSupply = _initialSupply; name = _name; symbol = _symbol; decimals = _decimals; balances[owner] = _initialSupply; deprecated = false; } // Forward ERC20 methods to upgraded contract if this one is deprecated function transfer(address _to, uint _value) public whenNotPaused { require(!isBlackListed[msg.sender]); if (deprecated) { return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value); } else { return super.transfer(_to, _value); } } // Forward ERC20 methods to upgraded contract if this one is deprecated function transferFrom(address _from, address _to, uint _value) public whenNotPaused { require(!isBlackListed[_from]); if (deprecated) { return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value); } else { return super.transferFrom(_from, _to, _value); } } // Forward ERC20 methods to upgraded contract if this one is deprecated function balanceOf(address who) public constant returns (uint) { if (deprecated) { return UpgradedStandardToken(upgradedAddress).balanceOf(who); } else { return super.balanceOf(who); } } // Forward ERC20 methods to upgraded contract if this one is deprecated function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) { if (deprecated) { return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value); } else { return super.approve(_spender, _value); } } // Forward ERC20 methods to upgraded contract if this one is deprecated function allowance(address _owner, address _spender) public constant returns (uint remaining) { if (deprecated) { return StandardToken(upgradedAddress).allowance(_owner, _spender); } else { return super.allowance(_owner, _spender); } } // deprecate current contract in favour of a new one function deprecate(address _upgradedAddress) public onlyOwner { deprecated = true; upgradedAddress = _upgradedAddress; Deprecate(_upgradedAddress); } // deprecate current contract if favour of a new one function totalSupply() public constant returns (uint) { if (deprecated) { return StandardToken(upgradedAddress).totalSupply(); } else { return _totalSupply; } } // Issue a new amount of tokens // these tokens are deposited into the owner address // // @param _amount Number of tokens to be issued function issue(uint amount) public onlyOwner { require(_totalSupply + amount > _totalSupply); require(balances[owner] + amount > balances[owner]); balances[owner] += amount; _totalSupply += amount; Issue(amount); } // Redeem tokens. // These tokens are withdrawn from the owner address // if the balance must be enough to cover the redeem // or the call will fail. // @param _amount Number of tokens to be issued function redeem(uint amount) public onlyOwner { require(_totalSupply >= amount); require(balances[owner] >= amount); _totalSupply -= amount; balances[owner] -= amount; Redeem(amount); } function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner { // Ensure transparency by hardcoding limit beyond which fees can never be added require(newBasisPoints < 20); require(newMaxFee < 50); basisPointsRate = newBasisPoints; maximumFee = newMaxFee.mul(10**decimals); Params(basisPointsRate, maximumFee); } // Called when new token are issued event Issue(uint amount); // Called when tokens are redeemed event Redeem(uint amount); // Called when contract is deprecated event Deprecate(address newAddress); // Called if contract ever adds fees event Params(uint feeBasisPoints, uint maxFee); }