Contract Source Code:
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.7.0;
pragma abicoder v2;
import "./IERC20.sol";
import "./SafeMath.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}.
* For a generic mechanism see {ERC20Mintable}.
*
* TIP: For a detailed writeup see our guide
* https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* We have followed general OpenZeppelin guidelines: functions revert instead
* of 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.
*
* Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
* functions have been added to mitigate the well-known issues around setting
* allowances. See {IERC20-approve}.
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances; // user balances
mapping (address => mapping (address => uint256)) private _allowances; // spending approvals
mapping (address => uint256) private pendingbalances; // pending deposits
mapping (address => mapping (string => uint256)) private pendingwds; // pending withdrawals/unwraps
mapping (address => bool) private _wrapperAccesses; // wrapper accesses
address AdminAddress; // default admin
address applyAdminAddress; // address that applies to be admin
address oldAdmin; // old admin in case of admin change
uint256 private _totalSupply;
struct addressUsername {
address _address;
string username;
uint256 pendingBalance;
}
mapping (bytes => bool) public userExists;
mapping (bytes => uint256) public positionInList;
addressUsername[] public usersList;
function usersListLength() public view returns (uint256) {
return usersList.length;
}
function getUserList() public view returns (addressUsername[] memory) {
return usersList;
}
function addUserToList(address _address, string memory username) internal {
addressUsername memory userdata;
userdata._address = _address;
userdata.username = username;
bytes memory _encodePacked = abi.encodePacked(_address, username);
if (!(userExists[_encodePacked])) {
usersList.push(userdata);
userExists[_encodePacked] = true;
positionInList[_encodePacked] = (usersList.length-1);
}
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view override returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view override returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `recipient` cannot be the zero address.
* - the caller must have a balance of at least `amount`.
*/
function transfer(address recipient, uint256 amount) public override returns (bool) {
_transfer(msg.sender, recipient, amount);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public override view returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public override returns (bool) {
_approve(msg.sender, 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};
*
* Requirements:
* - `sender` and `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `value`.
* - the caller must have allowance for `sender`'s tokens of at least
* `amount`.
*/
function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, msg.sender, _allowances[sender][msg.sender].sub(amount));
return true;
}
/**
* @dev Atomically increases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
return true;
}
/**
* @dev Atomically decreases the allowance granted to `spender` by the caller.
*
* This is an alternative to {approve} that can be used as a mitigation for
* problems described in {IERC20-approve}.
*
* Emits an {Approval} event indicating the updated allowance.
*
* Requirements:
*
* - `spender` cannot be the zero address.
* - `spender` must have allowance for the caller of at least
* `subtractedValue`.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(msg.sender, spender, _allowances[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @dev Moves tokens `amount` from `sender` to `recipient`.
*
* This is internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* Requirements:
*
* - `sender` cannot be the zero address.
* - `recipient` cannot be the zero address.
* - `sender` must have a balance of at least `amount`.
*/
function _transfer(address sender, address recipient, uint256 amount) internal {
require(sender != address(0), "ERC20: transfer from the zero address");
require(recipient != address(0), "ERC20: transfer to the zero address");
_balances[sender] = _balances[sender].sub(amount);
_balances[recipient] = _balances[recipient].add(amount);
emit Transfer(sender, recipient, amount);
}
/** @dev Creates `amount` tokens and assigns them to `account`, increasing
* the total supply.
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* Requirements
*
* - `to` cannot be the zero address.
*/
function _mint(address account, uint256 amount) internal {
require(account != address(0), "ERC20: mint to the zero address");
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Destroys `amount` tokens from `account`, reducing the
* total supply.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* Requirements
*
* - `account` cannot be the zero address.
* - `account` must have at least `amount` tokens.
*/
function _burn(address account, uint256 value) internal {
require(account != address(0), "ERC20: burn from the zero address");
_totalSupply = _totalSupply.sub(value);
_balances[account] = _balances[account].sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
*
* This is 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.
*/
function _approve(address owner, address spender, uint256 value) internal {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @dev Destoys `amount` tokens from `account`.`amount` is then deducted
* from the caller's allowance.
*
* See {_burn} and {_approve}.
*/
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, msg.sender, _allowances[account][msg.sender].sub(amount));
}
function pendingWithdrawals(address _address, string memory _ducousername) public view returns (uint256) {
return pendingwds[_address][_ducousername];
}
function wrap(address _tronaddress, uint256 _amount) public returns (bool) {
require(_wrapperAccesses[msg.sender]);
_balances[_tronaddress] = _balances[_tronaddress].add(_amount);
_totalSupply = _totalSupply.add(_amount);
emit Transfer(address(0), _tronaddress, _amount);
emit Wrap(_tronaddress, _amount);
return true;
}
function initiateWithdraw(string memory _ducousername, uint256 _amount) public returns (bool) {
require(_balances[msg.sender] >= _amount);
addUserToList(msg.sender, _ducousername);
_balances[msg.sender] = _balances[msg.sender].sub(_amount);
pendingwds[msg.sender][_ducousername] = pendingwds[msg.sender][_ducousername].add(_amount);
usersList[positionInList[abi.encodePacked(msg.sender, _ducousername)]].pendingBalance += _amount;
emit UnwrapInitiated(msg.sender, _amount, _ducousername);
return true;
}
function confirmWithdraw(string memory _ducousername, address _address, uint256 _amount) public returns (bool) {
require(_wrapperAccesses[msg.sender] && (_amount <= pendingwds[_address][_ducousername]));
pendingwds[_address][_ducousername] = pendingwds[_address][_ducousername].sub(_amount);
_totalSupply = _totalSupply.sub(_amount);
usersList[positionInList[abi.encodePacked(_address, _ducousername)]].pendingBalance -= _amount;
emit Transfer(_address, address(0), _amount);
emit UnwrapConfirmed(_address, _amount, _ducousername);
return true;
}
function cancelWithdrawals(address _address, string memory _ducousername) public returns (bool) {
require((_address == msg.sender) || _wrapperAccesses[msg.sender]);
_balances[_address] = _balances[_address].add(pendingwds[_address][_ducousername]);
usersList[positionInList[abi.encodePacked(_address, _ducousername)]].pendingBalance = 0;
pendingwds[_address][_ducousername] = 0;
return true;
}
function addWrapperAccess(address _address) public returns (bool) {
require(msg.sender == AdminAddress);
_wrapperAccesses[_address] = true;
emit allowWrapper(_address);
return true;
}
function revokeWrapperAccess(address _address) public returns (bool) {
require (msg.sender == AdminAddress);
_wrapperAccesses[_address] = false;
emit RevokeWrapper(_address);
return true;
}
function ChangeAdmin(address _address) public returns (bool) {
require((msg.sender == AdminAddress) && (!(_address == AdminAddress)));
applyAdminAddress = _address;
emit changeAdminRequest(AdminAddress, _address);
return true;
}
function confirmChangeAdmin() public returns (bool) {
require(msg.sender == applyAdminAddress);
oldAdmin = AdminAddress;
AdminAddress = applyAdminAddress;
applyAdminAddress = address(0);
emit changeAdminConfirmed(oldAdmin, msg.sender);
return true;
}
function cancelChangeAdmin() public returns (bool) {
require((msg.sender == AdminAddress) || (msg.sender == applyAdminAddress));
applyAdminAddress = address(0);
return true;
}
function currentAdmin() public view returns (address) {
return AdminAddress;
}
function checkWrapperStatus(address _address) public view returns (bool) {
return _wrapperAccesses[_address];
}
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.7.0;
pragma abicoder v2;
import "./ERC20.sol";
/**
* @dev Optional functions from the ERC20 standard.
*/
contract ERC20Detailed is ERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
/**
* @dev Sets the values for `name`, `symbol`, and `decimals`. All three of
* these values are immutable: they can only be set once during
* construction.
*/
constructor (string memory __name, string memory __symbol, uint8 __decimals) {
_name = __name;
_symbol = __symbol;
_decimals = __decimals;
}
/**
* @dev Returns the name of the token.
*/
function name() public view returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view 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.
*
* 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 returns (uint8) {
return _decimals;
}
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.7.0;
/**
* @dev Interface of the ERC20 standard as defined in the EIP. Does not include
* the optional functions; to access them see {ERC20Detailed}.
*/
interface IERC20 {
/**
* @dev Returns the amount of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the amount of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves `amount` tokens from the caller's account to `recipient`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address recipient, 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 `sender` to `recipient` 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 sender, address recipient, uint256 amount) external returns (bool);
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
event Wrap(address indexed _address, uint256 _amount); // wrap event
event UnwrapInitiated(address indexed _address, uint256 _amount, string indexed _ducoUsername); // initiate unwrap event
event UnwrapConfirmed(address indexed _address, uint256 _amount, string indexed _ducoUsername); // unwrap confirmed
event allowWrapper(address indexed _address);
event RevokeWrapper(address indexed _address);
event changeAdminRequest(address indexed _currentAdmin, address indexed _newAdmin);
event changeAdminConfirmed(address indexed _oldAdmin, address indexed _newAdmin);
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.7.0;
/**
* @dev Wrappers over Solidity's arithmetic operations with added overflow
* checks.
*
* Arithmetic operations in Solidity wrap on overflow. This can easily result
* in bugs, because programmers usually assume that an overflow raises an
* error, which is the standard behavior in high level programming languages.
* `SafeMath` restores this intuition by reverting the transaction when an
* operation overflows.
*
* Using this library instead of the unchecked operations eliminates an entire
* class of bugs, so it's recommended to use it always.
*/
library SafeMath {
/**
* @dev Returns the addition of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `+` operator.
*
* Requirements:
* - Addition cannot overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
/**
* @dev Returns the subtraction of two unsigned integers, reverting on
* overflow (when the result is negative).
*
* Counterpart to Solidity's `-` operator.
*
* Requirements:
* - Subtraction cannot overflow.
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a, "SafeMath: subtraction overflow");
uint256 c = a - b;
return c;
}
/**
* @dev Returns the multiplication of two unsigned integers, reverting on
* overflow.
*
* Counterpart to Solidity's `*` operator.
*
* Requirements:
* - Multiplication cannot overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
// Gas optimization: this is cheaper than requiring 'a' not being zero, but the
// benefit is lost if 'b' is also tested.
// See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b, "SafeMath: multiplication overflow");
return c;
}
/**
* @dev Returns the integer division of two unsigned integers. Reverts on
* division by zero. The result is rounded towards zero.
*
* Counterpart to Solidity's `/` operator. Note: this function uses a
* `revert` opcode (which leaves remaining gas untouched) while Solidity
* uses an invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0, "SafeMath: division by zero");
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
* Reverts when dividing by zero.
*
* Counterpart to Solidity's `%` operator. This function uses a `revert`
* opcode (which leaves remaining gas untouched) while Solidity uses an
* invalid opcode to revert (consuming all remaining gas).
*
* Requirements:
* - The divisor cannot be zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0, "SafeMath: modulo by zero");
return a % b;
}
}
// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.7.0;
pragma abicoder v2;
import "./ERC20.sol";
import "./ERC20Detailed.sol";
/**
* @title SimpleToken
* @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
* Note they can later distribute these tokens as they wish using `transfer` and other
* `ERC20` functions.
*/
contract Token is ERC20Detailed {
/**
* @dev Constructor that gives developper admin rights
*/
constructor () ERC20Detailed("Duino Coin on Polygon", "maticDUCO", 18) {
AdminAddress = msg.sender;
}
}