Contract Source Code:
pragma solidity >=0.4.24 <0.6.0;
import "./IERC20.sol";
import "./SafeMath.sol";
/**
* @title Standard ERC20 token
*
* @dev Implementation of the basic standard token.
* https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md
* Originally based on code by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
*/
contract ERC20 is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowed;
uint256 private _totalSupply;
/**
* @dev Total number of tokens in existence
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev Gets the balance of the specified address.
* @param owner The address to query the balance of.
* @return An uint256 representing the amount owned by the passed address.
*/
function balanceOf(address owner) public view returns (uint256) {
return _balances[owner];
}
/**
* @dev Function to check the amount of tokens that 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 uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowed[owner][spender];
}
/**
* @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, uint256 value) public returns (bool) {
require(value <= _balances[msg.sender], "ERC20: Overdrawn balance");
require(to != address(0));
_balances[msg.sender] = _balances[msg.sender].sub(value);
_balances[to] = _balances[to].add(value);
emit Transfer(msg.sender, to, value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
* 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
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
*/
function approve(address spender, uint256 value) public returns (bool) {
require(spender != address(0));
_allowed[msg.sender][spender] = value;
emit Approval(msg.sender, spender, value);
return true;
}
/**
* @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 uint256 the amount of tokens to be transferred
*/
function transferFrom(address from, address to, uint256 value) public returns (bool) {
require(value <= _balances[from], "ERC20: Overdrawn balance");
require(value <= _allowed[from][msg.sender]);
require(to != address(0));
_balances[from] = _balances[from].sub(value);
_balances[to] = _balances[to].add(value);
_allowed[from][msg.sender] = _allowed[from][msg.sender].sub(value);
emit Transfer(from, to, value);
return true;
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
* approve should be called when allowed_[_spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param spender The address which will spend the funds.
* @param addedValue The amount of tokens to increase the allowance by.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
require(spender != address(0));
_allowed[msg.sender][spender] = (_allowed[msg.sender][spender].add(addedValue));
emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
* approve should be called when allowed_[_spender] == 0. To decrement
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* @param spender The address which will spend the funds.
* @param subtractedValue The amount of tokens to decrease the allowance by.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
require(spender != address(0));
_allowed[msg.sender][spender] = (_allowed[msg.sender][spender].sub(subtractedValue));
emit Approval(msg.sender, spender, _allowed[msg.sender][spender]);
return true;
}
/**
* @dev Internal function that mints an amount of the token and assigns it to
* an account. This encapsulates the modification of balances such that the
* proper events are emitted.
* @param account The account that will receive the created tokens.
* @param amount The amount that will be created.
*/
function _mint(address account, uint256 amount) internal {
require(account != address(0));
_totalSupply = _totalSupply.add(amount);
_balances[account] = _balances[account].add(amount);
emit Transfer(address(0), account, amount);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account.
* @param account The account whose tokens will be burnt.
* @param amount The amount that will be burnt.
*/
function _burn(address account, uint256 amount) internal {
require(account != address(0));
require(amount <= _balances[account], "ERC20: Overdrawn balance");
_totalSupply = _totalSupply.sub(amount);
_balances[account] = _balances[account].sub(amount);
emit Transfer(account, address(0), amount);
}
/**
* @dev Internal function that burns an amount of the token of a given
* account, deducting from the sender's allowance for said account. Uses the
* internal burn function.
* @param account The account whose tokens will be burnt.
* @param amount The amount that will be burnt.
*/
function _burnFrom(address account, uint256 amount) internal {
require(amount <= _allowed[account][msg.sender], "ERC20: Overdrawn balance");
// Should https://github.com/OpenZeppelin/zeppelin-solidity/issues/707 be accepted,
// this function needs to emit an event with the updated approval.
_allowed[account][msg.sender] = _allowed[account][msg.sender].sub(amount);
_burn(account, amount);
}
}
pragma solidity >=0.4.24 <0.6.0;
import "./ERC20.sol";
/**
* @title Burnable Token
* @dev Token that can be irreversibly burned (destroyed).
*/
contract ERC20Burnable is ERC20 {
/**
* @dev Burns a specific amount of tokens.
* @param value The amount of token to be burned.
*/
function burn(uint256 value) public {
_burn(msg.sender, value);
}
/**
* @dev Burns a specific amount of tokens from the target address and decrements allowance
* @param from address The address which you want to send tokens from
* @param value uint256 The amount of token to be burned
*/
function burnFrom(address from, uint256 value) public {
_burnFrom(from, value);
}
/**
* @dev Overrides ERC20._burn in order for burn and burnFrom to emit
* an additional Burn event.
*/
function _burn(address who, uint256 value) internal {
super._burn(who, value);
}
}
pragma solidity >=0.4.24 <0.6.0;
import "./IERC20.sol";
/**
* @title ERC20Detailed token
* @dev The decimals are only for visualization purposes.
* All the operations are done using the smallest and indivisible token unit,
* just as on Ethereum all the operations are done in wei.
*/
contract ERC20Detailed is IERC20 {
string private _name;
string private _symbol;
uint8 private _decimals;
constructor(string memory name, string memory symbol, uint8 decimals) public {
_name = name;
_symbol = symbol;
_decimals = decimals;
}
/**
* @return the name of the token.
*/
function name() public view returns(string memory) {
return _name;
}
/**
* @return the symbol of the token.
*/
function symbol() public view returns(string memory) {
return _symbol;
}
/**
* @return the number of decimals of the token.
*/
function decimals() public view returns(uint8) {
return _decimals;
}
}
pragma solidity >=0.4.24 <0.6.0;
import "./ERC20Detailed.sol";
//import "./ERC20.sol";
import "./ERC20Burnable.sol";
import "./Stopable.sol";
contract GENToken is ERC20Detailed, /*ERC20,*/ ERC20Burnable, Stoppable {
constructor (
string memory name,
string memory symbol,
uint256 totalSupply,
uint8 decimals
) ERC20Detailed(name, symbol, decimals)
public {
_mint(owner(), totalSupply * 10**uint(decimals));
}
// Don't accept ETH
function () payable external {
revert();
}
function mint(address account, uint256 amount) public onlyOwner returns (bool) {
_mint(account, amount);
return true;
}
//------------------------
// Lock account transfer
mapping (address => uint256) private _lockTimes;
mapping (address => uint256) private _lockAmounts;
event LockChanged(address indexed account, uint256 releaseTime, uint256 amount);
function setLock(address account, uint256 releaseTime, uint256 amount) onlyOwner public {
_lockTimes[account] = releaseTime;
_lockAmounts[account] = amount;
emit LockChanged( account, releaseTime, amount );
}
function getLock(address account) public view returns (uint256 lockTime, uint256 lockAmount) {
return (_lockTimes[account], _lockAmounts[account]);
}
function _isLocked(address account, uint256 amount) internal view returns (bool) {
return _lockTimes[account] != 0 &&
_lockAmounts[account] != 0 &&
_lockTimes[account] > block.timestamp &&
(
balanceOf(account) <= _lockAmounts[account] ||
balanceOf(account).sub(_lockAmounts[account]) < amount
);
}
function transfer(address recipient, uint256 amount) enabled public returns (bool) {
require( !_isLocked( msg.sender, amount ) , "ERC20: Locked balance");
return super.transfer(recipient, amount);
}
function transferFrom(address sender, address recipient, uint256 amount) enabled public returns (bool) {
require( !_isLocked( sender, amount ) , "ERC20: Locked balance");
return super.transferFrom(sender, recipient, amount);
}
}
pragma solidity >=0.4.24 <0.6.0;
/**
* @title ERC20 interface
* @dev see https://github.com/ethereum/EIPs/issues/20
*/
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 who) external view returns (uint256);
/**
* @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 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 to, uint256 value) external returns (bool);
/**
* @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* > 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 `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 from, address to, uint256 value) 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);
}
pragma solidity >=0.4.24 <0.6.0;
/**
* @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 private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev The Ownable constructor sets the original `owner` of the contract to the sender
* account.
*/
constructor() public {
_owner = msg.sender;
}
/**
* @return the address of the owner.
*/
function owner() public view returns(address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(_isOwner());
_;
}
/**
* @return true if `msg.sender` is the owner of the contract.
*/
function _isOwner() internal view returns(bool) {
return 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 {
_transferOwnership(newOwner);
}
/**
* @dev Transfers control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0));
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
pragma solidity >=0.4.24 <0.6.0;
/**
* @title SafeMath
* @dev Math operations with safety checks that revert on error
*/
library SafeMath {
/**
* @dev Multiplies two numbers, reverts on 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-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b);
return c;
}
/**
* @dev Integer division of two numbers truncating the quotient, reverts on division by zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0); // Solidity only automatically asserts 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;
}
/**
* @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a);
uint256 c = a - b;
return c;
}
/**
* @dev Adds two numbers, reverts on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
/**
* @dev Divides two numbers and returns the remainder (unsigned integer modulo),
* reverts when dividing by zero.
*/
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0);
return a % b;
}
}
pragma solidity >=0.4.24 <0.6.0;
import "./Ownable.sol";
contract Stoppable is Ownable{
bool public stopped = false;
modifier enabled {
require (!stopped);
_;
}
function stop() external onlyOwner {
stopped = true;
}
function start() external onlyOwner {
stopped = false;
}
}